in-progress interpreter refactor

Will force-rewrite at several points.
2024-11-09 20:06:53 -07:00
430 changed files with 12130 additions and 14783 deletions
--- a/.github/ISSUE_TEMPLATE/bug-crash-report.yml
+++ b/.github/ISSUE_TEMPLATE/bug-crash-report.yml
@ -34,7 +34,6 @@ body:
    attributes:
      label: What android version do you use?
      options:
-        - Android 15
        - Android 14
        - Android 13
        - Android 12L
--- a/.github/workflows/android.yml
+++ b/.github/workflows/android.yml
@ -25,10 +25,8 @@ jobs:
        cache: gradle
    - name: Grant execute permission for gradlew
      run: chmod +x gradlew
-    - name: Check formatting with spotless
-      run: ./gradlew spotlessCheck
-    - name: Test musikr with Gradle
-      run: ./gradlew musikr:testDebug
+    - name: Test app with Gradle
+      run: ./gradlew app:testDebug
    - name: Build debug APK with Gradle
      run: ./gradlew app:packageDebug
    - name: Upload debug APK artifact
--- a/.gitignore
+++ b/.gitignore
@ -14,5 +14,3 @@ captures/
 *.iml
 .cxx
 .kotlin
-.aider*
-.env
--- a/.gitmodules
+++ b/.gitmodules
@ -1,8 +1,3 @@
 [submodule "media"]
 	path = media
 	url = https://github.com/OxygenCobalt/media.git
-
-[submodule "musikr/src/main/cpp/taglib"]
-	path = musikr/src/main/cpp/taglib
-	url = https://github.com/taglib/taglib.git
-	tag = ee1931b
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -1,100 +1,30 @@
 # Changelog

-## 4.0.3
-
-#### What's Improved
- Improved music loader pipeline efficiency
- Made cover.png support more flexible
- Albums with the same name but different album artists are now split
-if fully tagged with album artists
-
-#### What's Fixed
- Possibly fixed cache failures on large libraries
- Possibly fixed playback state saving failing on some devices
- Fixed issue where artists w/o songs would not have a cover
- Fixed music not being reloaded when music locations changed
- Fixed tasker media control not working
- Fixed tasker playback start command never finishing
-
-#### Dev/Meta
- Removed useless storage permissions
- Internal cleanup/simplification of musikr API
- Removed unused resources
-
-#### What's Fixed
-
-## 4.0.2
-
-#### What's New
- Added back in support for cover art from cover.png/cover.jpg
- Added "As is" cover art setting
- Option to include hidden files or not (off by default)
-
-#### What's Improved
- Reduced elevation contrast in black theme
-
-#### What's Fixed
- Fixed incorrect extension stripping on some files
- Fixed various errors in new branding
- Fixed MTE segfault from improper string handling
-
-#### What's Changed
- Hidden files no longer loaded by default
-
-## 4.0.1
-
-#### What's Fixed
- Fixed music loading hanging on files without tags
- Fixed playlists being destroyed in poorly tagged libraries
-
 ## 4.0.0

 #### What's New
- A total user interface refresh based on the latest Material Design specs
-	- New theme palettes
-	- Improved designs for playback and detail views
-	- New app branding and icon
-	- Refreshed round mode
-	- Less intrusive music loading indicators
- **Musikr**, a brand new music loading system
-	- Directly accesses user files rather than unreliable media database
-	- Uses faster and more capable native tag parsing
-	- Stores cover data on-device for fast and high-quality access
-	- New interpretation system with many quality-of-life improvements
 - Android 15 support
+- New app branding and icon
+- Refreshed playback design
+- Live widget preview on Android 15+
+- Added GitHub/email feedback forms to about page

 #### What's Improved
- Initial music loading is signifigantly faster and less resource intensive
- Album grouping no longer done with artist
+- Album grouping no longer done with artist in mind by default
 - MusicBrainz IDs will no longer split albums/artists in less tagged libraries
 - M3U playlist file name is now proposed if one cannot be found within the file
- Duration is now parsed from certain files that previously could not be parsed
- ID3v2 tags are now parsed from WAV files
- NN/TT tracks/discs are now handled in Vorbis
- Music library will is less likely to fail to respond to updates
- Hidden audio files can now be loaded
 - Sorting songs by date now uses songs date first, before the earliest album date
 - Added working layouts for small split-screen form factors
- Added fast scrolling in detail views
- Added ability to make issues and make feedback e-mails in-app

 #### What's Fixed
+- Music loader no longer spawns thousands of threads when scanning
+- Excessive CPU no longer spent showing music loading process
 - Fixed playback sheet flickering on warm start
 - No longer possible to save a sort with no direction specified
 - Fixed inconsistent corner radii in widget
- Possibly fixed foreground start music loading failures
- Fixed playlist view not exiting on deletion
-
-#### What's Changed
- Date added is now local to when the app discovers the file and will not
-persist long-term
- Songs with no album are now "Unknown album" rather than folder name
- Tab layout no longer changes depending on device configuration
- Round mode is now on by default

 #### Dev/Meta
 - No longer using custom logging setup
- Music loading split off into separate musikr module

 ## 3.6.3

--- a/README.md
+++ b/README.md
@ -2,8 +2,8 @@
 <h1 align="center"><b>Auxio</b></h1>
 <h4 align="center">A simple, rational music player for android.</h4>
 <p align="center">
-    <a href="https://github.com/oxygencobalt/Auxio/releases/tag/v4.0.4">
-        <img alt="Latest Version" src="https://img.shields.io/static/v1?label=tag&message=v4.0.4&color=64B5F6&style=flat">
+    <a href="https://github.com/oxygencobalt/Auxio/releases/tag/v3.6.3">
+        <img alt="Latest Version" src="https://img.shields.io/static/v1?label=tag&message=v3.6.3&color=64B5F6&style=flat">
    </a>
    <a href="https://github.com/oxygencobalt/Auxio/releases/">
        <img alt="Releases" src="https://img.shields.io/github/downloads/OxygenCobalt/Auxio/total.svg?color=4B95DE&style=flat">
@ -15,12 +15,7 @@
 </p>
 <h4 align="center"><a href="/CHANGELOG.md">Changelog</a> | <a href="https://github.com/OxygenCobalt/Auxio/wiki">Wiki</a> | <a href="https://github.com/OxygenCobalt/Auxio#Donate">Donate</a></h4>
 <p align="center">
-    <a href="https://f-droid.org/app/org.oxycblt.auxio"><img src="https://fdroid.gitlab.io/artwork/badge/get-it-on.png" width="250"></a>
-    <a href="https://accrescent.app/app/org.oxycblt.auxio">
-        <img alt="Get it on Accrescent" src="https://accrescent.app/badges/get-it-on.png" width="250">
-    </a>
-</p>
-<p align="center">
+    <a href="https://f-droid.org/app/org.oxycblt.auxio"><img src="https://fdroid.gitlab.io/artwork/badge/get-it-on.png" width="170"></a>
    <a href="https://hosted.weblate.org/engage/auxio/"><img height=64 src="https://hosted.weblate.org/widgets/auxio/-/strings/287x66-grey.png" alt="Translation status" /></a>
 </p>

@ -33,12 +28,14 @@ Auxio is a local music player with a fast, reliable UI/UX without the many usele
 ## Screenshots

 <p align="center">
-    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot0.png" width=250>
-    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot1.png" width=250>
-    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot2.png" width=250>
-    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot3.png" width=250>
-    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot4.png" width=250>
-    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot5.png" width=250>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot0.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot1.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot2.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot3.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot4.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot5.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot6.png" width=200>
+    <img src="fastlane/metadata/android/en-US/images/phoneScreenshots/shot7.png" width=200>
 </p>


@ -64,39 +61,29 @@ precise/original dates, sort tags, and more
 - Headset autoplay
 - Stylish widgets that automatically adapt to their size
 - Completely private and offline
- No rounded album covers (if you want them)
+- No rounded album covers (by default)

 ## Permissions

 - Storage (`READ_MEDIA_AUDIO`, `READ_EXTERNAL_STORAGE`) to read and play your music files
 - Services (`FOREGROUND_SERVICE`, `WAKE_LOCK`) to keep the music playing in the background
- Notifications (`POST_NOTIFICATION`) to indicate ongoing playback and music loading
+- Notifcations (`POST_NOTIFICATION`) to indicate ongoing playback and music loading

 ## Donate

 You can support Auxio's development through [my Github Sponsors page](https://github.com/sponsors/OxygenCobalt). Get the ability to prioritize features and have your profile added to the README, Release Changelogs, and even the app itself!

-<p align="center"><b>$16/month supporters:</b></p>
-
-<p align="center">
-    <a href="https://github.com/mark-pitblado"><img src="https://avatars.githubusercontent.com/u/86988982?v=4" width=75 /></a>
-    <br/>
-    <a href="https://github.com/mark-pitblado"><b>Mark Pitblado</b></a>
-</p>
-
 <p align="center"><b>$8/month supporters:</b></p>

 <p align="center">
    <a href="https://github.com/alanorth"><img src="https://avatars.githubusercontent.com/u/191754?v=4" width=50 /></a>
    <a href="https://github.com/dmint789"><img src="https://avatars.githubusercontent.com/u/53250435?v=4" width=50 /></a>
-    <a href="https://github.com/adventure-tense"><img src="https://avatars.githubusercontent.com/u/123326084?v=4" width=50 /></a>
-    <a href="https://github.com/slushspirit"><img src="https://avatars.githubusercontent.com/u/95902378?v=4" width=50 /></a>
+    <a href="https://github.com/yrliet"><img src="https://avatars.githubusercontent.com/u/151430565?v=4" width=50 /></a>
 </p>

 ## Building

-Auxio relies on a patched version of Media3 that enables some extra playback features, alongside taglib for metadata
-parsing. This adds some caveats to the build process:
+Auxio relies on a custom version of Media3 that enables some extra features. This adds some caveats to the build process:
 1. `cmake` and `ninja-build` must be installed before building the project.
 2. The project uses submodules, so when cloning initially, use `git clone --recurse-submodules` to properly
 download the external code.
--- a/app/NOTICE
+++ b/app/NOTICE
--- a/app/build.gradle
+++ b/app/build.gradle
@ -2,6 +2,7 @@ plugins {
    id "com.android.application"
    id "kotlin-android"
    id "androidx.navigation.safeargs.kotlin"
+    id "com.diffplug.spotless"
    id "kotlin-parcelize"
    id "dagger.hilt.android.plugin"
    id "kotlin-kapt"
@ -11,18 +12,20 @@ plugins {

 android {
    compileSdk 35
-    // Auxio implicitly depends on the native modules, explicitly specify it
-    // here so the libraries are still stripped.
-    ndkVersion ndk_version
+    // NDK is not used in Auxio explicitly (used in the ffmpeg extension), but we need to specify
+    // it here so that binary stripping will work.
+    // TODO: Eventually you might just want to start vendoring the FFMpeg extension so the
+    //  NDK use is unified
+    ndkVersion "26.3.11579264"
    namespace "org.oxycblt.auxio"

    defaultConfig {
        applicationId namespace
-        versionName "4.0.4"
-        versionCode 63
+        versionName "3.6.3"
+        versionCode 53

-        minSdk min_sdk
-        targetSdk target_sdk
+        minSdk 24
+        targetSdk 35

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
@ -77,13 +80,14 @@ dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"

-    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$kotlin_coroutines_version"
-    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-guava:$kotlin_coroutines_version"
+    def coroutines_version = '1.7.2'
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutines_version"
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-guava:$coroutines_version"

    // --- SUPPORT ---

    // General
-    implementation "androidx.core:core-ktx:$core_version"
+    implementation "androidx.core:core-ktx:1.15.0"
    implementation "androidx.appcompat:appcompat:1.7.0"
    implementation "androidx.activity:activity-ktx:1.9.3"
    // noinspection GradleDependency
@ -121,26 +125,20 @@ dependencies {
    implementation "androidx.preference:preference-ktx:1.2.1"

    // Database
+    def room_version = '2.6.1'
    implementation "androidx.room:room-runtime:$room_version"
    ksp "androidx.room:room-compiler:$room_version"
    implementation "androidx.room:room-ktx:$room_version"

-    // Build
-    coreLibraryDesugaring "com.android.tools:desugar_jdk_libs:$desugaring_version"
-
-    // --- SECOND PARTY ---
-
-    // Musikr
-    implementation project(":musikr")
-
    // --- THIRD PARTY ---

    // Exoplayer (Vendored)
    implementation project(":media-lib-exoplayer")
    implementation project(":media-lib-decoder-ffmpeg")
+    coreLibraryDesugaring "com.android.tools:desugar_jdk_libs:2.1.3"

    // Image loading
-    implementation 'io.coil-kt.coil3:coil-core:3.0.2'
+    implementation 'io.coil-kt:coil-base:2.4.0'

    // Material
    // TODO: Exactly figure out the conditions that the 1.7.0 ripple bug occurred so you can just
@ -164,4 +162,25 @@ dependencies {

    // Fuzzy search
    implementation 'org.apache.commons:commons-text:1.9'
+
+    // Testing
+    debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.12'
+    testImplementation "junit:junit:4.13.2"
+    testImplementation "io.mockk:mockk:1.13.7"
+    testImplementation "org.robolectric:robolectric:4.11"
+    testImplementation 'androidx.test:core-ktx:1.6.1'
+    androidTestImplementation 'androidx.test.ext:junit:1.2.1'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.6.1'
+}
+
+spotless {
+    kotlin {
+        target "src/**/*.kt"
+        ktfmt().dropboxStyle()
+        licenseHeaderFile("NOTICE")
+    }
+}
+
+afterEvaluate {
+    preDebugBuild.dependsOn spotlessApply
 }
--- a/app/src/debug/res/values/donottranslate.xml
+++ b/app/src/debug/res/values/donottranslate.xml
@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
    <string name="info_app_name" translatable="false">Auxio Debug</string>
-    <string name="pkg_authority_cover">org.oxycblt.auxio.debug.image.CoverProvider</string>
 </resources>
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@ -2,6 +2,9 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">

+    <!-- Android 13 uses READ_MEDIA_AUDIO instead of READ_EXTERNAL_STORAGE -->
+    <uses-permission android:name="android.permission.READ_MEDIA_AUDIO" />
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" android:maxSdkVersion="32" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_DATA_SYNC"  />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MEDIA_PLAYBACK"  />
@ -97,15 +100,6 @@
            </intent-filter>
        </service>

-        <!--
-        Expose Auxio's cover data to the android system
-        -->
-        <provider
-            android:name=".image.CoverProvider"
-            android:authorities="@string/pkg_authority_cover"
-            android:exported="true"
-            tools:ignore="ExportedContentProvider" />
-
        <!--
        Work around apps that blindly query for ACTION_MEDIA_BUTTON working.
        See the class for more info.
--- a/app/src/main/ic_launcher-playstore.png
+++ b/app/src/main/ic_launcher-playstore.png
--- a/app/src/main/java/com/google/android/material/bottomsheet/BackportBottomSheetBehavior.java
+++ b/app/src/main/java/com/google/android/material/bottomsheet/BackportBottomSheetBehavior.java
@ -1309,6 +1309,7 @@ public class BackportBottomSheetBehavior<V extends View> extends CoordinatorLayo
              + " should not be set externally.");
    }
    if (!hideable && state == STATE_HIDDEN) {
+      Log.w(TAG, "Cannot set state: " + state);
      return;
    }
    final int finalState;
@ -1632,13 +1633,12 @@ public class BackportBottomSheetBehavior<V extends View> extends CoordinatorLayo
      return;
    }
    BackEventCompat backEvent = bottomContainerBackHelper.onHandleBackInvoked();
-    boolean canActuallyHide = hideable && isHideableWhenDragging();
    if (backEvent == null || VERSION.SDK_INT < VERSION_CODES.UPSIDE_DOWN_CAKE) {
      // If using traditional button system nav or if pre-U, just hide or collapse the bottom sheet.
-      setState(canActuallyHide ? STATE_HIDDEN : STATE_COLLAPSED);
+      setState(hideable ? STATE_HIDDEN : STATE_COLLAPSED);
      return;
    }
-    if (canActuallyHide) {
+    if (hideable && isHideableWhenDragging()) {
      bottomContainerBackHelper.finishBackProgressNotPersistent(
          backEvent,
          new AnimatorListenerAdapter() {
--- a/app/src/main/java/org/oxycblt/auxio/AuxioService.kt
+++ b/app/src/main/java/org/oxycblt/auxio/AuxioService.kt
@ -36,7 +36,6 @@ import dagger.hilt.android.AndroidEntryPoint
 import javax.inject.Inject
 import org.oxycblt.auxio.music.service.MusicServiceFragment
 import org.oxycblt.auxio.playback.service.PlaybackServiceFragment
-import timber.log.Timber

@AndroidEntryPoint
 class AuxioService :
@ -54,30 +53,24 @@ class AuxioService :
        musicFragment = musicFragmentFactory.create(this, this, this)
        sessionToken = playbackFragment.attach()
        musicFragment.attach()
-        Timber.d("Service Created")
    }

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        // TODO: Start command occurring from a foreign service basically implies a detached
        //  service, we might need more handling here.
-        super.onStartCommand(intent, flags, startId)
        onHandleForeground(intent)
-        // If we die we want to not restart, we will immediately try to foreground in and just
-        // fail to start again since the activity will be dead too. This is not the semantically
-        // "correct" flag (normally you want START_STICKY for playback) but we need this to avoid
-        // weird foreground errors.
-        return START_NOT_STICKY
+        return super.onStartCommand(intent, flags, startId)
    }

    override fun onBind(intent: Intent): IBinder? {
-        val binder = super.onBind(intent)
        onHandleForeground(intent)
-        return binder
+        return super.onBind(intent)
    }

    private fun onHandleForeground(intent: Intent?) {
+        val startId = intent?.getIntExtra(INTENT_KEY_START_ID, -1) ?: -1
        musicFragment.start()
-        playbackFragment.start(intent)
+        playbackFragment.start(startId)
    }

    override fun onTaskRemoved(rootIntent: Intent?) {
@ -141,7 +134,6 @@ class AuxioService :
            }
            // Nothing changed, but don't show anything music related since we can always
            // index during playback.
-            isForeground = true
        } else {
            musicFragment.createNotification {
                if (it != null) {
--- a/app/src/main/java/org/oxycblt/auxio/IntegerTable.kt
+++ b/app/src/main/java/org/oxycblt/auxio/IntegerTable.kt
@ -65,8 +65,6 @@ object IntegerTable {
    const val START_ID_ACTIVITY = 0xA050
    /** Tasker AuxioService Start ID */
    const val START_ID_TASKER = 0xA051
-    /** MediaButtonReceiver AuxioService Start ID */
-    const val START_ID_MEDIA_BUTTON = 0xA052
    /** RepeatMode.NONE */
    const val REPEAT_MODE_NONE = 0xA100
    /** RepeatMode.ALL */
@ -125,10 +123,10 @@ object IntegerTable {
    const val ACTION_MODE_SHUFFLE = 0xA11B
    /** CoverMode.Off */
    const val COVER_MODE_OFF = 0xA11C
-    /** CoverMode.Balanced */
-    const val COVER_MODE_BALANCED = 0xA11D
+    /** CoverMode.MediaStore */
+    const val COVER_MODE_MEDIA_STORE = 0xA11D
    /** CoverMode.Quality */
-    const val COVER_MODE_HIGH_QUALITY = 0xA11E
+    const val COVER_MODE_QUALITY = 0xA11E
    /** PlaySong.FromAll */
    const val PLAY_SONG_FROM_ALL = 0xA11F
    /** PlaySong.FromAlbum */
@ -141,8 +139,4 @@ object IntegerTable {
    const val PLAY_SONG_FROM_PLAYLIST = 0xA123
    /** PlaySong.ByItself */
    const val PLAY_SONG_BY_ITSELF = 0xA124
-    /** CoverMode.SaveSpace */
-    const val COVER_MODE_SAVE_SPACE = 0xA125
-    /** CoverMode.AsIs */
-    const val COVER_MODE_AS_IS = 0xA126
 }
--- a/app/src/main/java/org/oxycblt/auxio/MainFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/MainFragment.kt
@ -18,6 +18,7 @@
 
 package org.oxycblt.auxio

+import android.animation.ValueAnimator
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.ViewTreeObserver
@ -26,7 +27,6 @@ import androidx.activity.BackEventCompat
 import androidx.activity.OnBackPressedCallback
 import androidx.core.view.ViewCompat
 import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.activityViewModels
 import androidx.navigation.findNavController
 import androidx.navigation.fragment.findNavController
@ -50,8 +50,10 @@ import org.oxycblt.auxio.home.HomeViewModel
 import org.oxycblt.auxio.home.Outer
 import org.oxycblt.auxio.list.ListViewModel
 import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicType
 import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.OpenPanel
 import org.oxycblt.auxio.playback.PlaybackBottomSheetBehavior
 import org.oxycblt.auxio.playback.PlaybackViewModel
@ -68,8 +70,6 @@ import org.oxycblt.auxio.util.getDimen
 import org.oxycblt.auxio.util.lazyReflectedMethod
 import org.oxycblt.auxio.util.navigateSafe
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -257,9 +257,9 @@ class MainFragment :
    }

    override fun onPreDraw(): Boolean {
-        // This is where I shove literally all the UI logic that won't behave any callback
-        // or "normal" method I've tried. Surely running this on every frame will actually cause
-        // it to work properly!
+        // TODO: Due to draw caching even *this* isn't effective enough to avoid the bottom
+        //  sheets continually getting stuck. I need something with even more frequent updates,
+        //  or otherwise bottom sheets get stuck.

        // We overload CoordinatorLayout far too much to rely on any of it's typical
        // listener functionality. Just update all transitions before every draw. Should
@ -367,10 +367,6 @@ class MainFragment :
        requireNotNull(sheetBackCallback) { "SheetBackPressedCallback was not available" }
            .invalidateEnabled()

-        // Stop the FrameLayout containing the fabs from eating touch events elsewhere
-        binding.mainFabContainer.isVisible =
-            binding.homeNewPlaylistFab.mainFab.isVisible || binding.homeShuffleFab.isVisible
-
        return true
    }

@ -408,6 +404,9 @@ class MainFragment :
    }

    private fun updateIndexerState(state: IndexingState?) {
+        // TODO: Make music loading experience a bit more pleasant
+        //  1. Loading placeholder for item lists
+        //  2. Rework the "No Music" case to not be an error and instead result in a placeholder
        if (state is IndexingState.Completed && state.error == null) {
            L.d("Received ok response")
            val binding = requireBinding()
@ -513,6 +512,8 @@ class MainFragment :
        }
    }

+    private var scrimAnimator: ValueAnimator? = null
+
    private fun updateSpeedDial(open: Boolean) {
        requireNotNull(speedDialBackCallback) { "SpeedDialBackPressedCallback was not available" }
            .invalidateEnabled(open)
--- a/app/src/main/java/org/oxycblt/auxio/detail/AlbumDetailFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/AlbumDetailFragment.kt
@ -22,7 +22,6 @@ import android.os.Bundle
 import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
 import androidx.recyclerview.widget.LinearSmoothScroller
-import androidx.recyclerview.widget.RecyclerView
 import dagger.hilt.android.AndroidEntryPoint
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentDetailBinding
@ -30,9 +29,12 @@ import org.oxycblt.auxio.detail.list.AlbumDetailListAdapter
 import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.ListFragment
 import org.oxycblt.auxio.list.menu.Menu
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.PlaylistDecision
 import org.oxycblt.auxio.music.PlaylistMessage
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.resolveNames
 import org.oxycblt.auxio.playback.PlaybackDecision
 import org.oxycblt.auxio.playback.formatDurationMs
@ -42,10 +44,6 @@ import org.oxycblt.auxio.util.getPlural
 import org.oxycblt.auxio.util.navigateSafe
 import org.oxycblt.auxio.util.showToast
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -117,7 +115,7 @@ class AlbumDetailFragment : DetailFragment<Album, Song>() {
        binding.detailToolbarTitle.text = name
        binding.detailCover.bind(album)
        // The type text depends on the release type (Album, EP, Single, etc.)
-        binding.detailType.text = album.releaseType.resolve(context)
+        binding.detailType.text = getString(album.releaseType.stringRes)
        binding.detailName.text = name
        // Artist name maps to the subhead text
        binding.detailSubhead.apply {
@ -133,7 +131,7 @@ class AlbumDetailFragment : DetailFragment<Album, Song>() {
        // Date, song count, and duration map to the info text
        binding.detailInfo.apply {
            // Fall back to a friendlier "No date" text if the album doesn't have date information
-            val date = album.dates?.resolve(context) ?: context.getString(R.string.def_date)
+            val date = album.dates?.resolveDate(context) ?: context.getString(R.string.def_date)
            val songCount = context.getPlural(R.plurals.fmt_song_count, album.songs.size)
            val duration = album.durationMs.formatDurationMs(true)
            text = context.getString(R.string.fmt_three, date, songCount, duration)
@ -142,15 +140,9 @@ class AlbumDetailFragment : DetailFragment<Album, Song>() {
        binding.detailPlayButton?.setOnClickListener {
            playbackModel.play(unlikelyToBeNull(detailModel.currentAlbum.value))
        }
-        binding.detailToolbarPlay.setOnClickListener {
-            playbackModel.play(unlikelyToBeNull(detailModel.currentAlbum.value))
-        }
        binding.detailShuffleButton?.setOnClickListener {
            playbackModel.shuffle(unlikelyToBeNull(detailModel.currentAlbum.value))
        }
-        binding.detailToolbarShuffle.setOnClickListener {
-            playbackModel.shuffle(unlikelyToBeNull(detailModel.currentAlbum.value))
-        }
        updatePlayback(
            playbackModel.song.value, playbackModel.parent.value, playbackModel.isPlaying.value)
    }
@ -299,11 +291,6 @@ class AlbumDetailFragment : DetailFragment<Album, Song>() {
            // RecyclerView will scroll assuming it has the total height of the screen (i.e a
            // collapsed appbar), so we need to collapse the appbar if that's the case.
            binding.detailAppbar.setExpanded(false)
-            if (!binding.detailRecycler.canScroll()) {
-                // Don't scroll if the RecyclerView goes off screen. If we go anyway, overscroll
-                // kicks in and creates a weird bounce effect.
-                return
-            }
            binding.detailRecycler.post {
                // Use a custom smooth scroller that will settle the item in the middle of
                // the screen rather than the end.
@ -329,6 +316,4 @@ class AlbumDetailFragment : DetailFragment<Album, Song>() {
            }
        }
    }
-
-    private fun RecyclerView.canScroll() = computeVerticalScrollRange() > height
 }
--- a/app/src/main/java/org/oxycblt/auxio/detail/ArtistDetailFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/ArtistDetailFragment.kt
@ -29,9 +29,13 @@ import org.oxycblt.auxio.detail.list.ArtistDetailListAdapter
 import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.ListFragment
 import org.oxycblt.auxio.list.menu.Menu
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.PlaylistDecision
 import org.oxycblt.auxio.music.PlaylistMessage
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.resolveNames
 import org.oxycblt.auxio.playback.PlaybackDecision
 import org.oxycblt.auxio.util.collect
@ -40,11 +44,6 @@ import org.oxycblt.auxio.util.getPlural
 import org.oxycblt.auxio.util.navigateSafe
 import org.oxycblt.auxio.util.showToast
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -164,15 +163,9 @@ class ArtistDetailFragment : DetailFragment<Artist, Music>() {
        binding.detailPlayButton?.setOnClickListener {
            playbackModel.play(unlikelyToBeNull(detailModel.currentArtist.value))
        }
-        binding.detailToolbarPlay.setOnClickListener {
-            playbackModel.play(unlikelyToBeNull(detailModel.currentArtist.value))
-        }
        binding.detailShuffleButton?.setOnClickListener {
            playbackModel.shuffle(unlikelyToBeNull(detailModel.currentArtist.value))
        }
-        binding.detailToolbarShuffle.setOnClickListener {
-            playbackModel.shuffle(unlikelyToBeNull(detailModel.currentArtist.value))
-        }
        updatePlayback(
            playbackModel.song.value, playbackModel.parent.value, playbackModel.isPlaying.value)
    }
--- a/app/src/main/java/org/oxycblt/auxio/detail/DetailFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/DetailFragment.kt
@ -35,13 +35,13 @@ import org.oxycblt.auxio.list.ListFragment
 import org.oxycblt.auxio.list.ListViewModel
 import org.oxycblt.auxio.list.PlainDivider
 import org.oxycblt.auxio.list.PlainHeader
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicViewModel
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.util.getDimenPixels
 import org.oxycblt.auxio.util.overrideOnOverflowMenuClick
 import org.oxycblt.auxio.util.setFullWidthLookup
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent

 abstract class DetailFragment<P : MusicParent, C : Music> :
    ListFragment<C, FragmentDetailBinding>(),
@ -123,9 +123,6 @@ abstract class DetailFragment<P : MusicParent, C : Music> :
        val detailContent = binding.detailToolbarContent
        detailContent.alpha = inRatio
        detailContent.translationY = spacingSmall * (1 - inRatio)
-
-        // Enable fast scrolling once fully collapsed
-        binding.detailRecycler.fastScrollingEnabled = ratio == 1f
    }

    abstract fun onOpenParentMenu()
--- a/app/src/main/java/org/oxycblt/auxio/detail/DetailGenerator.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/DetailGenerator.kt
@ -23,17 +23,17 @@ import javax.inject.Inject
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.list.ListSettings
 import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicRepository
 import org.oxycblt.auxio.music.MusicType
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.tag.Disc
-import org.oxycblt.musikr.tag.ReleaseType
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.info.Disc
+import org.oxycblt.auxio.music.info.ReleaseType
 import timber.log.Timber as L

 interface DetailGenerator {
@ -121,7 +121,7 @@ private class DetailGeneratorImpl(
    }

    override fun album(uid: Music.UID): Detail<Album>? {
-        val album = musicRepository.library?.findAlbum(uid) ?: return null
+        val album = musicRepository.deviceLibrary?.findAlbum(uid) ?: return null
        val songs = listSettings.albumSongSort.songs(album.songs)
        val discs = songs.groupBy { it.disc }
        val section =
@ -134,7 +134,7 @@ private class DetailGeneratorImpl(
    }

    override fun artist(uid: Music.UID): Detail<Artist>? {
-        val artist = musicRepository.library?.findArtist(uid) ?: return null
+        val artist = musicRepository.deviceLibrary?.findArtist(uid) ?: return null
        val grouping =
            artist.explicitAlbums.groupByTo(sortedMapOf()) {
                // Remap the complicated ReleaseType data structure into detail sections
@ -173,14 +173,14 @@ private class DetailGeneratorImpl(
    }

    override fun genre(uid: Music.UID): Detail<Genre>? {
-        val genre = musicRepository.library?.findGenre(uid) ?: return null
+        val genre = musicRepository.deviceLibrary?.findGenre(uid) ?: return null
        val artists = DetailSection.Artists(GENRE_ARTIST_SORT.artists(genre.artists))
        val songs = DetailSection.Songs(listSettings.genreSongSort.songs(genre.songs))
        return Detail(genre, listOf(artists, songs))
    }

    override fun playlist(uid: Music.UID): Detail<Playlist>? {
-        val playlist = musicRepository.library?.findPlaylist(uid) ?: return null
+        val playlist = musicRepository.userLibrary?.findPlaylist(uid) ?: return null
        if (playlist.songs.isNotEmpty()) {
            val songs = DetailSection.Songs(playlist.songs)
            return Detail(playlist, listOf(songs))
--- a/app/src/main/java/org/oxycblt/auxio/detail/DetailViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/DetailViewModel.kt
@ -22,14 +22,16 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import javax.inject.Inject
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.yield
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.detail.list.DiscDivider
 import org.oxycblt.auxio.detail.list.DiscHeader
 import org.oxycblt.auxio.detail.list.EditHeader
-import org.oxycblt.auxio.detail.list.SongProperty
 import org.oxycblt.auxio.detail.list.SortHeader
 import org.oxycblt.auxio.list.BasicHeader
 import org.oxycblt.auxio.list.Item
@ -38,20 +40,21 @@ import org.oxycblt.auxio.list.PlainDivider
 import org.oxycblt.auxio.list.PlainHeader
 import org.oxycblt.auxio.list.adapter.UpdateInstructions
 import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicRepository
 import org.oxycblt.auxio.music.MusicType
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.metadata.AudioProperties
 import org.oxycblt.auxio.playback.PlaySong
 import org.oxycblt.auxio.playback.PlaybackSettings
 import org.oxycblt.auxio.util.Event
 import org.oxycblt.auxio.util.MutableEvent
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -66,11 +69,11 @@ class DetailViewModel
 constructor(
    private val listSettings: ListSettings,
    private val musicRepository: MusicRepository,
+    private val audioPropertiesFactory: AudioProperties.Factory,
    private val playbackSettings: PlaybackSettings,
    detailGeneratorFactory: DetailGenerator.Factory
 ) : ViewModel(), DetailGenerator.Invalidator {
    private val _toShow = MutableEvent<Show>()
-
    /**
     * A [Show] command that is awaiting a view capable of responding to it. Null if none currently.
     */
@ -79,34 +82,30 @@ constructor(

    // --- SONG ---

-    private val _currentSong = MutableStateFlow<Song?>(null)
+    private var currentSongJob: Job? = null

+    private val _currentSong = MutableStateFlow<Song?>(null)
    /** The current [Song] to display. Null if there is nothing to show. */
    val currentSong: StateFlow<Song?>
        get() = _currentSong

-    private val _currentSongProperties = MutableStateFlow<List<SongProperty>>(listOf())
-
-    /** The current properties of [currentSong]. Empty if nothing to show. */
-    val currentSongProperties: StateFlow<List<SongProperty>>
-        get() = _currentSongProperties
+    private val _songAudioProperties = MutableStateFlow<AudioProperties?>(null)
+    /** The [AudioProperties] of the currently shown [Song]. Null if not loaded yet. */
+    val songAudioProperties: StateFlow<AudioProperties?> = _songAudioProperties

    // --- ALBUM ---

    private val _currentAlbum = MutableStateFlow<Album?>(null)
-
    /** The current [Album] to display. Null if there is nothing to show. */
    val currentAlbum: StateFlow<Album?>
        get() = _currentAlbum

    private val _albumSongList = MutableStateFlow(listOf<Item>())
-
    /** The current list data derived from [currentAlbum]. */
    val albumSongList: StateFlow<List<Item>>
        get() = _albumSongList

    private val _albumSongInstructions = MutableEvent<UpdateInstructions>()
-
    /** Instructions for updating [albumSongList] in the UI. */
    val albumSongInstructions: Event<UpdateInstructions>
        get() = _albumSongInstructions
@ -122,18 +121,15 @@ constructor(
    // --- ARTIST ---

    private val _currentArtist = MutableStateFlow<Artist?>(null)
-
    /** The current [Artist] to display. Null if there is nothing to show. */
    val currentArtist: StateFlow<Artist?>
        get() = _currentArtist

    private val _artistSongList = MutableStateFlow(listOf<Item>())
-
    /** The current list derived from [currentArtist]. */
    val artistSongList: StateFlow<List<Item>> = _artistSongList

    private val _artistSongInstructions = MutableEvent<UpdateInstructions>()
-
    /** Instructions for updating [artistSongList] in the UI. */
    val artistSongInstructions: Event<UpdateInstructions>
        get() = _artistSongInstructions
@ -149,18 +145,15 @@ constructor(
    // --- GENRE ---

    private val _currentGenre = MutableStateFlow<Genre?>(null)
-
    /** The current [Genre] to display. Null if there is nothing to show. */
    val currentGenre: StateFlow<Genre?>
        get() = _currentGenre

    private val _genreSongList = MutableStateFlow(listOf<Item>())
-
    /** The current list data derived from [currentGenre]. */
    val genreSongList: StateFlow<List<Item>> = _genreSongList

    private val _genreSongInstructions = MutableEvent<UpdateInstructions>()
-
    /** Instructions for updating [artistSongList] in the UI. */
    val genreSongInstructions: Event<UpdateInstructions>
        get() = _genreSongInstructions
@ -176,24 +169,20 @@ constructor(
    // --- PLAYLIST ---

    private val _currentPlaylist = MutableStateFlow<Playlist?>(null)
-
    /** The current [Playlist] to display. Null if there is nothing to do. */
    val currentPlaylist: StateFlow<Playlist?>
        get() = _currentPlaylist

    private val _playlistSongList = MutableStateFlow(listOf<Item>())
-
    /** The current list data derived from [currentPlaylist] */
    val playlistSongList: StateFlow<List<Item>> = _playlistSongList

    private val _playlistSongInstructions = MutableEvent<UpdateInstructions>()
-
    /** Instructions for updating [playlistSongList] in the UI. */
    val playlistSongInstructions: Event<UpdateInstructions>
        get() = _playlistSongInstructions

    private val _editedPlaylist = MutableStateFlow<List<Song>?>(null)
-
    /**
     * The new playlist songs created during the current editing session. Null if no editing session
     * is occurring.
@ -319,14 +308,14 @@ constructor(
    }

    /**
-     * Set a new [currentSong] from it's [Music.UID]. [currentSong] will be updated to align with
-     * the new [Song].
+     * Set a new [currentSong] from it's [Music.UID]. [currentSong] and [songAudioProperties] will
+     * be updated to align with the new [Song].
     *
     * @param uid The UID of the [Song] to load. Must be valid.
     */
    fun setSong(uid: Music.UID) {
        L.d("Opening song $uid")
-        _currentSong.value = musicRepository.library?.findSong(uid)?.also(::refreshAudioInfo)
+        _currentSong.value = musicRepository.deviceLibrary?.findSong(uid)?.also(::refreshAudioInfo)
        if (_currentSong.value == null) {
            L.w("Given song UID was invalid")
        }
@ -522,32 +511,16 @@ constructor(
    }

    private fun refreshAudioInfo(song: Song) {
-        _currentSongProperties.value = buildList {
-            add(SongProperty(R.string.lbl_name, SongProperty.Value.MusicName(song)))
-            add(SongProperty(R.string.lbl_album, SongProperty.Value.MusicName(song.album)))
-            add(SongProperty(R.string.lbl_artists, SongProperty.Value.MusicNames(song.artists)))
-            add(SongProperty(R.string.lbl_genres, SongProperty.Value.MusicNames(song.genres)))
-            song.date?.let { add(SongProperty(R.string.lbl_date, SongProperty.Value.ItemDate(it))) }
-            song.track?.let {
-                add(SongProperty(R.string.lbl_track, SongProperty.Value.Number(it, null)))
-            }
-            song.disc?.let {
-                add(SongProperty(R.string.lbl_disc, SongProperty.Value.Number(it.number, it.name)))
-            }
-            add(SongProperty(R.string.lbl_path, SongProperty.Value.ItemPath(song.path)))
-            add(SongProperty(R.string.lbl_size, SongProperty.Value.Size(song.size)))
-            add(SongProperty(R.string.lbl_duration, SongProperty.Value.Duration(song.durationMs)))
-            add(SongProperty(R.string.lbl_format, SongProperty.Value.ItemFormat(song.format)))
-            add(SongProperty(R.string.lbl_bitrate, SongProperty.Value.Bitrate(song.bitrateKbps)))
-            add(
-                SongProperty(
-                    R.string.lbl_sample_rate, SongProperty.Value.SampleRate(song.sampleRateHz)))
-            song.replayGainAdjustment.track?.let {
-                add(SongProperty(R.string.lbl_replaygain_track, SongProperty.Value.Decibels(it)))
-            }
-            song.replayGainAdjustment.album?.let {
-                add(SongProperty(R.string.lbl_replaygain_album, SongProperty.Value.Decibels(it)))
-            }
+        L.d("Refreshing audio info")
+        // Clear any previous job in order to avoid stale data from appearing in the UI.
+        currentSongJob?.cancel()
+        _songAudioProperties.value = null
+        currentSongJob =
+            viewModelScope.launch(Dispatchers.IO) {
+                val info = audioPropertiesFactory.extract(song)
+                yield()
+                L.d("Updating audio info to $info")
+                _songAudioProperties.value = info
            }
    }

--- a/app/src/main/java/org/oxycblt/auxio/detail/GenreDetailFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/GenreDetailFragment.kt
@ -29,9 +29,13 @@ import org.oxycblt.auxio.detail.list.GenreDetailListAdapter
 import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.ListFragment
 import org.oxycblt.auxio.list.menu.Menu
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.PlaylistDecision
 import org.oxycblt.auxio.music.PlaylistMessage
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackDecision
 import org.oxycblt.auxio.util.collect
 import org.oxycblt.auxio.util.collectImmediately
@ -39,11 +43,6 @@ import org.oxycblt.auxio.util.getPlural
 import org.oxycblt.auxio.util.navigateSafe
 import org.oxycblt.auxio.util.showToast
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -133,15 +132,9 @@ class GenreDetailFragment : DetailFragment<Genre, Music>() {
        binding.detailPlayButton?.setOnClickListener {
            playbackModel.play(unlikelyToBeNull(detailModel.currentGenre.value))
        }
-        binding.detailToolbarPlay.setOnClickListener {
-            playbackModel.play(unlikelyToBeNull(detailModel.currentGenre.value))
-        }
        binding.detailShuffleButton?.setOnClickListener {
            playbackModel.shuffle(unlikelyToBeNull(detailModel.currentGenre.value))
        }
-        binding.detailToolbarShuffle.setOnClickListener {
-            playbackModel.shuffle(unlikelyToBeNull(detailModel.currentGenre.value))
-        }
        updatePlayback(
            playbackModel.song.value, playbackModel.parent.value, playbackModel.isPlaying.value)
    }
--- a/app/src/main/java/org/oxycblt/auxio/detail/PlaylistDetailFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/PlaylistDetailFragment.kt
@ -35,9 +35,13 @@ import org.oxycblt.auxio.detail.list.PlaylistDragCallback
 import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.ListFragment
 import org.oxycblt.auxio.list.menu.Menu
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
+import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.music.PlaylistDecision
 import org.oxycblt.auxio.music.PlaylistMessage
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.external.M3U
 import org.oxycblt.auxio.playback.PlaybackDecision
 import org.oxycblt.auxio.playback.formatDurationMs
 import org.oxycblt.auxio.ui.DialogAwareNavigationListener
@ -48,11 +52,6 @@ import org.oxycblt.auxio.util.getPlural
 import org.oxycblt.auxio.util.navigateSafe
 import org.oxycblt.auxio.util.showToast
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.playlist.m3u.M3U
 import timber.log.Timber as L

 /**
@ -232,24 +231,12 @@ class PlaylistDetailFragment :
                playbackModel.play(unlikelyToBeNull(detailModel.currentPlaylist.value))
            }
        }
-        binding.detailToolbarPlay.apply {
-            isEnabled = playable
-            setOnClickListener {
-                playbackModel.play(unlikelyToBeNull(detailModel.currentPlaylist.value))
-            }
-        }
        binding.detailShuffleButton?.apply {
            isEnabled = playable
            setOnClickListener {
                playbackModel.shuffle(unlikelyToBeNull(detailModel.currentPlaylist.value))
            }
        }
-        binding.detailToolbarShuffle.apply {
-            isEnabled = playable
-            setOnClickListener {
-                playbackModel.shuffle(unlikelyToBeNull(detailModel.currentPlaylist.value))
-            }
-        }
        updatePlayback(
            playbackModel.song.value, playbackModel.parent.value, playbackModel.isPlaying.value)
    }
--- a/app/src/main/java/org/oxycblt/auxio/detail/SongDetailDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/SongDetailDialog.kt
@ -18,7 +18,9 @@
 
 package org.oxycblt.auxio.detail

+import android.content.Context
 import android.os.Bundle
+import android.text.format.Formatter
 import android.view.LayoutInflater
 import androidx.appcompat.app.AlertDialog
 import androidx.fragment.app.activityViewModels
@ -30,9 +32,16 @@ import org.oxycblt.auxio.databinding.DialogSongDetailBinding
 import org.oxycblt.auxio.detail.list.SongProperty
 import org.oxycblt.auxio.detail.list.SongPropertyAdapter
 import org.oxycblt.auxio.list.adapter.UpdateInstructions
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.info.Name
+import org.oxycblt.auxio.music.metadata.AudioProperties
+import org.oxycblt.auxio.music.resolveNames
+import org.oxycblt.auxio.playback.formatDurationMs
+import org.oxycblt.auxio.playback.replaygain.formatDb
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Song
+import org.oxycblt.auxio.util.concatLocalized
 import timber.log.Timber as L

 /**
@ -62,19 +71,74 @@ class SongDetailDialog : ViewBindingMaterialDialogFragment<DialogSongDetailBindi
        // DetailViewModel handles most initialization from the navigation argument.
        detailModel.setSong(args.songUid)
        detailModel.toShow.consume()
-        collectImmediately(detailModel.currentSong, ::updateSong)
-        collectImmediately(detailModel.currentSongProperties, ::updateSongProperties)
+        collectImmediately(detailModel.currentSong, detailModel.songAudioProperties, ::updateSong)
    }

-    private fun updateSong(song: Song?) {
-        L.d("No song to show, navigating away")
+    private fun updateSong(song: Song?, info: AudioProperties?) {
        if (song == null) {
+            L.d("No song to show, navigating away")
            findNavController().navigateUp()
            return
        }
+
+        if (info != null) {
+            val context = requireContext()
+            detailAdapter.update(
+                buildList {
+                    add(SongProperty(R.string.lbl_name, song.zipName(context)))
+                    add(SongProperty(R.string.lbl_album, song.album.zipName(context)))
+                    add(SongProperty(R.string.lbl_artists, song.artists.zipNames(context)))
+                    add(SongProperty(R.string.lbl_genres, song.genres.resolveNames(context)))
+                    song.date?.let { add(SongProperty(R.string.lbl_date, it.resolve(context))) }
+                    song.track?.let {
+                        add(SongProperty(R.string.lbl_track, getString(R.string.fmt_number, it)))
+                    }
+                    song.disc?.let {
+                        val formattedNumber = getString(R.string.fmt_number, it.number)
+                        val zipped =
+                            if (it.name != null) {
+                                getString(R.string.fmt_zipped_names, formattedNumber, it.name)
+                            } else {
+                                formattedNumber
+                            }
+                        add(SongProperty(R.string.lbl_disc, zipped))
+                    }
+                    add(SongProperty(R.string.lbl_path, song.path.resolve(context)))
+                    info.resolvedMimeType.resolveName(context)?.let {
+                        add(SongProperty(R.string.lbl_format, it))
+                    }
+                    add(
+                        SongProperty(
+                            R.string.lbl_size, Formatter.formatFileSize(context, song.size)))
+                    add(SongProperty(R.string.lbl_duration, song.durationMs.formatDurationMs(true)))
+                    info.bitrateKbps?.let {
+                        add(SongProperty(R.string.lbl_bitrate, getString(R.string.fmt_bitrate, it)))
+                    }
+                    info.sampleRateHz?.let {
+                        add(
+                            SongProperty(
+                                R.string.lbl_sample_rate, getString(R.string.fmt_sample_rate, it)))
+                    }
+                    song.replayGainAdjustment.track?.let {
+                        add(SongProperty(R.string.lbl_replaygain_track, it.formatDb(context)))
+                    }
+                    song.replayGainAdjustment.album?.let {
+                        add(SongProperty(R.string.lbl_replaygain_album, it.formatDb(context)))
+                    }
+                },
+                UpdateInstructions.Replace(0))
+        }
    }

-    private fun updateSongProperties(songProperties: List<SongProperty>) {
-        detailAdapter.update(songProperties, UpdateInstructions.Replace(0))
+    private fun <T : Music> T.zipName(context: Context): String {
+        val name = name
+        return if (name is Name.Known && name.sort != null) {
+            getString(R.string.fmt_zipped_names, name.resolve(context), name.sort)
+        } else {
+            name.resolve(context)
        }
+    }
+
+    private fun <T : Music> List<T>.zipNames(context: Context) =
+        concatLocalized(context) { it.zipName(context) }
 }
--- a/app/src/main/java/org/oxycblt/auxio/detail/decision/ArtistShowChoice.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/decision/ArtistShowChoice.kt
@ -25,10 +25,9 @@ import org.oxycblt.auxio.list.ClickableListListener
 import org.oxycblt.auxio.list.adapter.FlexibleListAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
 import org.oxycblt.auxio.list.recycler.DialogRecyclerView
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Artist

 /**
 * A [FlexibleListAdapter] that displays a list of [Artist] navigation choices, for use with
--- a/app/src/main/java/org/oxycblt/auxio/detail/decision/DetailDecisionViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/decision/DetailDecisionViewModel.kt
@ -23,12 +23,12 @@ import dagger.hilt.android.lifecycle.HiltViewModel
 import javax.inject.Inject
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicRepository
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Library
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Song
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.device.DeviceLibrary
 import timber.log.Timber as L

 /**
@ -56,9 +56,9 @@ class DetailPickerViewModel @Inject constructor(private val musicRepository: Mus

    override fun onMusicChanges(changes: MusicRepository.Changes) {
        if (!changes.deviceLibrary) return
-        val library = musicRepository.library ?: return
+        val deviceLibrary = musicRepository.deviceLibrary ?: return
        // Need to sanitize different items depending on the current set of choices.
-        _artistChoices.value = _artistChoices.value?.sanitize(library)
+        _artistChoices.value = _artistChoices.value?.sanitize(deviceLibrary)
        L.d("Updated artist choices: ${_artistChoices.value}")
    }

@ -98,15 +98,16 @@ sealed interface ArtistShowChoices {
    val uid: Music.UID
    /** The current [Artist] choices. */
    val choices: List<Artist>
-    /** Sanitize this instance with a [Library]. */
-    fun sanitize(newLibrary: Library): ArtistShowChoices?
+    /** Sanitize this instance with a [DeviceLibrary]. */
+    fun sanitize(newLibrary: DeviceLibrary): ArtistShowChoices?

    /** Backing implementation of [ArtistShowChoices] that is based on a [Song]. */
    class FromSong(val song: Song) : ArtistShowChoices {
        override val uid = song.uid
        override val choices = song.artists

-        override fun sanitize(newLibrary: Library) = newLibrary.findSong(uid)?.let { FromSong(it) }
+        override fun sanitize(newLibrary: DeviceLibrary) =
+            newLibrary.findSong(uid)?.let { FromSong(it) }
    }

    /** Backing implementation of [ArtistShowChoices] that is based on an [Album]. */
@ -114,7 +115,7 @@ sealed interface ArtistShowChoices {
        override val uid = album.uid
        override val choices = album.artists

-        override fun sanitize(newLibrary: Library) =
+        override fun sanitize(newLibrary: DeviceLibrary) =
            newLibrary.findAlbum(uid)?.let { FromAlbum(it) }
    }
 }
--- a/app/src/main/java/org/oxycblt/auxio/detail/decision/ShowArtistDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/decision/ShowArtistDialog.kt
@ -32,9 +32,9 @@ import org.oxycblt.auxio.databinding.DialogMusicChoicesBinding
 import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.list.ClickableListListener
 import org.oxycblt.auxio.list.adapter.UpdateInstructions
+import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Artist
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/detail/list/AlbumDetailListAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/list/AlbumDetailListAdapter.kt
@ -35,14 +35,14 @@ import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.SelectableListListener
 import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.info.Disc
+import org.oxycblt.auxio.music.info.resolveNumber
 import org.oxycblt.auxio.playback.formatDurationMs
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.getAttrColorCompat
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.tag.Disc

 /**
 * An [DetailListAdapter] implementing the header and sub-items for the [Album] detail view.
@ -121,7 +121,7 @@ private class DiscHeaderViewHolder(private val binding: ItemDiscHeaderBinding) :
     */
    fun bind(discHeader: DiscHeader) {
        val disc = discHeader.inner
-        binding.discNumber.text = disc.resolve(binding.context)
+        binding.discNumber.text = disc.resolveNumber(binding.context)
        binding.discName.apply {
            text = disc?.name
            isGone = disc?.name == null
--- a/app/src/main/java/org/oxycblt/auxio/detail/list/ArtistDetailListAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/list/ArtistDetailListAdapter.kt
@ -29,13 +29,12 @@ import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.SelectableListListener
 import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Song

 /**
 * A [DetailListAdapter] implementing the header and sub-items for the [Artist] detail view.
@ -105,7 +104,8 @@ private class ArtistAlbumViewHolder private constructor(private val binding: Ite
        binding.parentName.text = album.name.resolve(binding.context)
        binding.parentInfo.text =
            // Fall back to a friendlier "No date" text if the album doesn't have date information
-            album.dates?.resolve(binding.context) ?: binding.context.getString(R.string.def_date)
+            album.dates?.resolveDate(binding.context)
+                ?: binding.context.getString(R.string.def_date)
    }

    override fun updatePlayingIndicator(isActive: Boolean, isPlaying: Boolean) {
--- a/app/src/main/java/org/oxycblt/auxio/detail/list/DetailListAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/list/DetailListAdapter.kt
@ -35,9 +35,9 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
 import org.oxycblt.auxio.list.recycler.BasicHeaderViewHolder
 import org.oxycblt.auxio.list.recycler.DividerViewHolder
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Music

 /**
 * A [RecyclerView.Adapter] that implements shared behavior between lists of child items in the
--- a/app/src/main/java/org/oxycblt/auxio/detail/list/GenreDetailListAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/list/GenreDetailListAdapter.kt
@ -24,10 +24,10 @@ import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
 import org.oxycblt.auxio.list.recycler.ArtistViewHolder
 import org.oxycblt.auxio.list.recycler.SongViewHolder
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Song
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.Song

 /**
 * A [DetailListAdapter] implementing the header and sub-items for the [Genre] detail view.
--- a/app/src/main/java/org/oxycblt/auxio/detail/list/PlaylistDetailListAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/list/PlaylistDetailListAdapter.kt
@ -40,13 +40,12 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
 import org.oxycblt.auxio.list.recycler.MaterialDragCallback
 import org.oxycblt.auxio.list.recycler.SongViewHolder
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.resolveNames
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.getAttrColorCompat
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/detail/list/SongPropertyAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/list/SongPropertyAdapter.kt
@ -18,26 +18,17 @@
 
 package org.oxycblt.auxio.detail.list

-import android.text.format.Formatter
 import android.view.View
 import android.view.ViewGroup
 import androidx.annotation.StringRes
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.ItemSongPropertyBinding
+import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.adapter.FlexibleListAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
 import org.oxycblt.auxio.list.recycler.DialogRecyclerView
-import org.oxycblt.auxio.music.resolve
-import org.oxycblt.auxio.music.resolveNames
-import org.oxycblt.auxio.playback.formatDurationMs
-import org.oxycblt.auxio.playback.replaygain.formatDb
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.fs.Format
-import org.oxycblt.musikr.fs.Path
-import org.oxycblt.musikr.tag.Date

 /**
 * An adapter for [SongProperty] instances.
@ -62,31 +53,7 @@ class SongPropertyAdapter :
 * @param value The value of the property.
 * @author Alexander Capehart (OxygenCobalt)
 */
-data class SongProperty(@StringRes val name: Int, val value: Value) {
-    sealed interface Value {
-        data class MusicName(val music: Music) : Value
-
-        data class MusicNames(val name: List<Music>) : Value
-
-        data class Number(val value: Int, val subtitle: String?) : Value
-
-        data class ItemDate(val date: Date) : Value
-
-        data class ItemPath(val path: Path) : Value
-
-        data class Size(val sizeBytes: Long) : Value
-
-        data class Duration(val durationMs: Long) : Value
-
-        data class ItemFormat(val format: Format) : Value
-
-        data class Bitrate(val kbps: Int) : Value
-
-        data class SampleRate(val hz: Int) : Value
-
-        data class Decibels(val value: Float) : Value
-    }
-}
+data class SongProperty(@StringRes val name: Int, val value: String) : Item

 /**
 * A [RecyclerView.ViewHolder] that displays a [SongProperty]. Use [from] to create an instance.
@ -98,58 +65,7 @@ class SongPropertyViewHolder private constructor(private val binding: ItemSongPr
    fun bind(property: SongProperty) {
        val context = binding.context
        binding.propertyName.hint = context.getString(property.name)
-        when (property.value) {
-            is SongProperty.Value.MusicName -> {
-                val music = property.value.music
-                binding.propertyValue.setText(music.name.resolve(context))
-            }
-            is SongProperty.Value.MusicNames -> {
-                val names = property.value.name.resolveNames(context)
-                binding.propertyValue.setText(names)
-            }
-            is SongProperty.Value.Number -> {
-                val value = context.getString(R.string.fmt_number, property.value.value)
-                val subtitle = property.value.subtitle
-                binding.propertyValue.setText(
-                    if (subtitle != null) {
-                        context.getString(R.string.fmt_zipped_names, value, subtitle)
-                    } else {
-                        value
-                    })
-            }
-            is SongProperty.Value.ItemDate -> {
-                val date = property.value.date
-                binding.propertyValue.setText(date.resolve(context))
-            }
-            is SongProperty.Value.ItemPath -> {
-                val path = property.value.path
-                binding.propertyValue.setText(path.resolve(context))
-            }
-            is SongProperty.Value.Size -> {
-                val size = property.value.sizeBytes
-                binding.propertyValue.setText(Formatter.formatFileSize(context, size))
-            }
-            is SongProperty.Value.Duration -> {
-                val duration = property.value.durationMs
-                binding.propertyValue.setText(duration.formatDurationMs(true))
-            }
-            is SongProperty.Value.ItemFormat -> {
-                val format = property.value.format
-                binding.propertyValue.setText(format.resolve(context))
-            }
-            is SongProperty.Value.Bitrate -> {
-                val kbps = property.value.kbps
-                binding.propertyValue.setText(context.getString(R.string.fmt_bitrate, kbps))
-            }
-            is SongProperty.Value.SampleRate -> {
-                val hz = property.value.hz
-                binding.propertyValue.setText(context.getString(R.string.fmt_sample_rate, hz))
-            }
-            is SongProperty.Value.Decibels -> {
-                val value = property.value.value
-                binding.propertyValue.setText(value.formatDb(context))
-            }
-        }
+        binding.propertyValue.setText(property.value)
    }

    companion object {
--- a/app/src/main/java/org/oxycblt/auxio/detail/sort/AlbumSongSortDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/sort/AlbumSongSortDialog.kt
@ -26,8 +26,8 @@ import org.oxycblt.auxio.databinding.DialogSortBinding
 import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.list.sort.Sort
 import org.oxycblt.auxio.list.sort.SortDialog
+import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Album
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/detail/sort/ArtistSongSortDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/sort/ArtistSongSortDialog.kt
@ -26,8 +26,8 @@ import org.oxycblt.auxio.databinding.DialogSortBinding
 import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.list.sort.Sort
 import org.oxycblt.auxio.list.sort.SortDialog
+import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Artist
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/detail/sort/GenreSongSortDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/sort/GenreSongSortDialog.kt
@ -26,8 +26,8 @@ import org.oxycblt.auxio.databinding.DialogSortBinding
 import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.list.sort.Sort
 import org.oxycblt.auxio.list.sort.SortDialog
+import org.oxycblt.auxio.music.Genre
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Genre
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/detail/sort/PlaylistSongSortDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/detail/sort/PlaylistSongSortDialog.kt
@ -26,8 +26,8 @@ import org.oxycblt.auxio.databinding.DialogSortBinding
 import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.list.sort.Sort
 import org.oxycblt.auxio.list.sort.SortDialog
+import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Playlist
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/home/EdgeFrameLayout.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/EdgeFrameLayout.kt
@ -16,7 +16,7 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.auxio.ui
+package org.oxycblt.auxio.home

 import android.content.Context
 import android.util.AttributeSet
@ -40,6 +40,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
    }

    override fun onApplyWindowInsets(insets: WindowInsets): WindowInsets {
+        // Prevent excessive layouts by using translation instead of padding.
        updatePadding(bottom = insets.systemBarInsetsCompat.bottom)
        return insets
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/ErrorDetailsDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/ErrorDetailsDialog.kt
@ -24,11 +24,9 @@ import android.os.Build
 import android.os.Bundle
 import android.view.LayoutInflater
 import androidx.appcompat.app.AlertDialog
-import androidx.fragment.app.viewModels
 import androidx.navigation.fragment.navArgs
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.DialogErrorDetailsBinding
-import org.oxycblt.auxio.music.MusicViewModel
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.getSystemServiceCompat
 import org.oxycblt.auxio.util.openInBrowser
@ -44,12 +42,10 @@ import org.oxycblt.auxio.util.showToast
 class ErrorDetailsDialog : ViewBindingMaterialDialogFragment<DialogErrorDetailsBinding>() {
    private val args: ErrorDetailsDialogArgs by navArgs()
    private var clipboardManager: ClipboardManager? = null
-    private val musicModel: MusicViewModel by viewModels()

    override fun onConfigDialog(builder: AlertDialog.Builder) {
        builder
            .setTitle(R.string.lbl_error_info)
-            .setNeutralButton(R.string.lbl_retry) { _, _ -> musicModel.refresh() }
            .setPositiveButton(R.string.lbl_report) { _, _ ->
                requireContext().openInBrowser(LINK_ISSUES)
            }
--- a/app/src/main/java/org/oxycblt/auxio/home/HomeFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/HomeFragment.kt
@ -22,10 +22,10 @@ import android.annotation.SuppressLint
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.MenuItem
+import android.view.View
 import androidx.activity.result.ActivityResultLauncher
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.core.view.MenuCompat
-import androidx.core.view.isInvisible
 import androidx.core.view.isVisible
 import androidx.core.view.updatePadding
 import androidx.fragment.app.Fragment
@ -37,10 +37,12 @@ import androidx.recyclerview.widget.RecyclerView
 import androidx.viewpager2.adapter.FragmentStateAdapter
 import androidx.viewpager2.widget.ViewPager2
 import com.google.android.material.appbar.AppBarLayout
+import com.google.android.material.floatingactionbutton.FloatingActionButton
 import com.google.android.material.tabs.TabLayoutMediator
 import com.google.android.material.transition.MaterialSharedAxis
 import dagger.hilt.android.AndroidEntryPoint
 import java.lang.reflect.Field
+import java.lang.reflect.Method
 import kotlin.math.abs
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentHomeBinding
@ -51,27 +53,31 @@ import org.oxycblt.auxio.home.list.ArtistListFragment
 import org.oxycblt.auxio.home.list.GenreListFragment
 import org.oxycblt.auxio.home.list.PlaylistListFragment
 import org.oxycblt.auxio.home.list.SongListFragment
-import org.oxycblt.auxio.home.tabs.NamedTabStrategy
+import org.oxycblt.auxio.home.tabs.AdaptiveTabStrategy
 import org.oxycblt.auxio.home.tabs.Tab
 import org.oxycblt.auxio.list.ListViewModel
 import org.oxycblt.auxio.list.SelectionFragment
 import org.oxycblt.auxio.list.menu.Menu
+import org.oxycblt.auxio.music.IndexingProgress
 import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicType
 import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.NoAudioPermissionException
+import org.oxycblt.auxio.music.NoMusicException
+import org.oxycblt.auxio.music.PERMISSION_READ_AUDIO
+import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.music.PlaylistDecision
 import org.oxycblt.auxio.music.PlaylistMessage
+import org.oxycblt.auxio.music.external.M3U
 import org.oxycblt.auxio.playback.PlaybackDecision
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.util.collect
 import org.oxycblt.auxio.util.collectImmediately
 import org.oxycblt.auxio.util.lazyReflectedField
+import org.oxycblt.auxio.util.lazyReflectedMethod
 import org.oxycblt.auxio.util.navigateSafe
 import org.oxycblt.auxio.util.showToast
-import org.oxycblt.musikr.IndexingProgress
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.playlist.m3u.M3U
 import timber.log.Timber as L

 /**
@ -172,7 +178,6 @@ class HomeFragment :

        // --- VIEWMODEL SETUP ---
        collect(homeModel.recreateTabs.flow, ::handleRecreate)
-        collect(homeModel.chooseMusicLocations.flow, ::handleChooseFolders)
        collectImmediately(homeModel.currentTabType, ::updateCurrentTab)
        collect(detailModel.toShow.flow, ::handleShow)
        collect(listModel.menu.flow, ::handleMenu)
@ -266,7 +271,9 @@ class HomeFragment :

        // Set up the mapping between the ViewPager and TabLayout.
        TabLayoutMediator(
-                binding.homeTabs, binding.homePager, NamedTabStrategy(homeModel.currentTabTypes))
+                binding.homeTabs,
+                binding.homePager,
+                AdaptiveTabStrategy(requireContext(), homeModel.currentTabTypes))
            .attach()
    }

@ -297,49 +304,98 @@ class HomeFragment :
        homeModel.recreateTabs.consume()
    }

-    private fun handleChooseFolders(unit: Unit?) {
-        if (unit == null) {
-            return
-        }
-        findNavController().navigateSafe(HomeFragmentDirections.chooseLocations())
-        homeModel.chooseMusicLocations.consume()
-    }
-
    private fun updateIndexerState(state: IndexingState?) {
+        // TODO: Make music loading experience a bit more pleasant
+        //  1. Loading placeholder for item lists
+        //  2. Rework the "No Music" case to not be an error and instead result in a placeholder
        val binding = requireBinding()
        when (state) {
-            is IndexingState.Completed -> {
-                binding.homeIndexingContainer.isInvisible = state.error == null
-                binding.homeIndexingProgress.isInvisible = state.error != null
-                binding.homeIndexingError.isInvisible = state.error == null
-                if (state.error != null) {
-                    binding.homeIndexingContainer.setOnClickListener {
-                        findNavController()
-                            .navigateSafe(HomeFragmentDirections.reportError(state.error))
-                    }
-                } else {
-                    binding.homeIndexingContainer.setOnClickListener(null)
-                }
-            }
-            is IndexingState.Indexing -> {
-                binding.homeIndexingContainer.isInvisible = false
-                binding.homeIndexingProgress.apply {
-                    isInvisible = false
-                    when (state.progress) {
-                        is IndexingProgress.Songs -> {
-                            isIndeterminate = false
-                            progress = state.progress.loaded
-                            max = state.progress.explored
-                        }
-                        is IndexingProgress.Indeterminate -> {
-                            isIndeterminate = true
-                        }
-                    }
-                }
-                binding.homeIndexingError.isInvisible = true
-            }
+            is IndexingState.Completed -> setupCompleteState(binding, state.error)
+            is IndexingState.Indexing -> setupIndexingState(binding, state.progress)
            null -> {
-                binding.homeIndexingContainer.isInvisible = true
+                L.d("Indexer is in indeterminate state")
+                binding.homeIndexingContainer.visibility = View.INVISIBLE
+            }
+        }
+    }
+
+    private fun setupCompleteState(binding: FragmentHomeBinding, error: Exception?) {
+        if (error == null) {
+            L.d("Received ok response")
+            binding.homeIndexingContainer.visibility = View.INVISIBLE
+            return
+        }
+
+        L.d("Received non-ok response")
+        val context = requireContext()
+        binding.homeIndexingContainer.visibility = View.VISIBLE
+        binding.homeIndexingProgress.visibility = View.INVISIBLE
+        binding.homeIndexingActions.visibility = View.VISIBLE
+        when (error) {
+            is NoAudioPermissionException -> {
+                L.d("Showing permission prompt")
+                binding.homeIndexingStatus.setText(R.string.err_no_perms)
+                // Configure the action to act as a permission launcher.
+                binding.homeIndexingTry.apply {
+                    text = context.getString(R.string.lbl_grant)
+                    setOnClickListener {
+                        requireNotNull(storagePermissionLauncher) {
+                                "Permission launcher was not available"
+                            }
+                            .launch(PERMISSION_READ_AUDIO)
+                    }
+                }
+                binding.homeIndexingMore.visibility = View.GONE
+            }
+            is NoMusicException -> {
+                L.d("Showing no music error")
+                binding.homeIndexingStatus.setText(R.string.err_no_music)
+                // Configure the action to act as a reload trigger.
+                binding.homeIndexingTry.apply {
+                    visibility = View.VISIBLE
+                    text = context.getString(R.string.lbl_retry)
+                    setOnClickListener { musicModel.refresh() }
+                }
+                binding.homeIndexingMore.visibility = View.GONE
+            }
+            else -> {
+                L.d("Showing generic error")
+                binding.homeIndexingStatus.setText(R.string.err_index_failed)
+                // Configure the action to act as a reload trigger.
+                binding.homeIndexingTry.apply {
+                    visibility = View.VISIBLE
+                    text = context.getString(R.string.lbl_retry)
+                    setOnClickListener { musicModel.rescan() }
+                }
+                binding.homeIndexingMore.apply {
+                    visibility = View.VISIBLE
+                    setOnClickListener {
+                        findNavController().navigateSafe(HomeFragmentDirections.reportError(error))
+                    }
+                }
+            }
+        }
+    }
+
+    private fun setupIndexingState(binding: FragmentHomeBinding, progress: IndexingProgress) {
+        // Remove all content except for the progress indicator.
+        binding.homeIndexingContainer.visibility = View.VISIBLE
+        binding.homeIndexingProgress.visibility = View.VISIBLE
+        binding.homeIndexingActions.visibility = View.INVISIBLE
+
+        binding.homeIndexingStatus.setText(R.string.lng_indexing)
+        when (progress) {
+            is IndexingProgress.Indeterminate -> {
+                // In a query/initialization state, show a generic loading status.
+                binding.homeIndexingProgress.isIndeterminate = true
+            }
+            is IndexingProgress.Songs -> {
+                // Actively loading songs, show the current progress.
+                binding.homeIndexingProgress.apply {
+                    isIndeterminate = false
+                    max = progress.total
+                    this.progress = progress.current
+                }
            }
        }
    }
@ -508,5 +564,11 @@ class HomeFragment :
    private companion object {
        val VP_RECYCLER_FIELD: Field by lazyReflectedField(ViewPager2::class, "mRecyclerView")
        val RV_TOUCH_SLOP_FIELD: Field by lazyReflectedField(RecyclerView::class, "mTouchSlop")
+        val FAB_HIDE_FROM_USER_FIELD: Method by
+            lazyReflectedMethod(
+                FloatingActionButton::class,
+                "hide",
+                FloatingActionButton.OnVisibilityChangedListener::class,
+                Boolean::class)
    }
 }
--- a/app/src/main/java/org/oxycblt/auxio/home/HomeGenerator.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/HomeGenerator.kt
@ -22,13 +22,13 @@ import javax.inject.Inject
 import org.oxycblt.auxio.home.tabs.Tab
 import org.oxycblt.auxio.list.ListSettings
 import org.oxycblt.auxio.list.adapter.UpdateInstructions
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
 import org.oxycblt.auxio.music.MusicRepository
 import org.oxycblt.auxio.music.MusicType
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import timber.log.Timber as L

 interface HomeGenerator {
@ -36,8 +36,6 @@ interface HomeGenerator {

    fun release()

-    fun empty(): Boolean
-
    fun songs(): List<Song>

    fun albums(): List<Album>
@ -51,8 +49,6 @@ interface HomeGenerator {
    fun tabs(): List<MusicType>

    interface Invalidator {
-        fun invalidateEmpty() {}
-
        fun invalidateMusic(type: MusicType, instructions: UpdateInstructions)

        fun invalidateTabs()
@ -123,10 +119,8 @@ private class HomeGeneratorImpl(
    }

    override fun onMusicChanges(changes: MusicRepository.Changes) {
-        invalidator.invalidateEmpty()
-
-        val library = musicRepository.library
-        if (changes.deviceLibrary && library != null) {
+        val deviceLibrary = musicRepository.deviceLibrary
+        if (changes.deviceLibrary && deviceLibrary != null) {
            L.d("Refreshing library")
            // Get the each list of items in the library to use as our list data.
            // Applying the preferred sorting to them.
@ -136,7 +130,8 @@ private class HomeGeneratorImpl(
            invalidator.invalidateMusic(MusicType.GENRES, UpdateInstructions.Diff)
        }

-        if (changes.userLibrary && library != null) {
+        val userLibrary = musicRepository.userLibrary
+        if (changes.userLibrary && userLibrary != null) {
            L.d("Refreshing playlists")
            invalidator.invalidateMusic(MusicType.PLAYLISTS, UpdateInstructions.Diff)
        }
@ -148,16 +143,15 @@ private class HomeGeneratorImpl(
        homeSettings.unregisterListener(this)
    }

-    override fun empty() = musicRepository.library?.empty() ?: true
-
    override fun songs() =
-        musicRepository.library?.let { listSettings.songSort.songs(it.songs) } ?: emptyList()
+        musicRepository.deviceLibrary?.let { listSettings.songSort.songs(it.songs) } ?: emptyList()

    override fun albums() =
-        musicRepository.library?.let { listSettings.albumSort.albums(it.albums) } ?: emptyList()
+        musicRepository.deviceLibrary?.let { listSettings.albumSort.albums(it.albums) }
+            ?: emptyList()

    override fun artists() =
-        musicRepository.library?.let { deviceLibrary ->
+        musicRepository.deviceLibrary?.let { deviceLibrary ->
            val sorted = listSettings.artistSort.artists(deviceLibrary.artists)
            if (homeSettings.shouldHideCollaborators) {
                sorted.filter { it.explicitAlbums.isNotEmpty() }
@ -167,10 +161,11 @@ private class HomeGeneratorImpl(
        } ?: emptyList()

    override fun genres() =
-        musicRepository.library?.let { listSettings.genreSort.genres(it.genres) } ?: emptyList()
+        musicRepository.deviceLibrary?.let { listSettings.genreSort.genres(it.genres) }
+            ?: emptyList()

    override fun playlists() =
-        musicRepository.library?.let { listSettings.playlistSort.playlists(it.playlists) }
+        musicRepository.userLibrary?.let { listSettings.playlistSort.playlists(it.playlists) }
            ?: emptyList()

    override fun tabs() = homeSettings.homeTabs.filterIsInstance<Tab.Visible>().map { it.type }
--- a/app/src/main/java/org/oxycblt/auxio/home/HomeViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/HomeViewModel.kt
@ -27,16 +27,16 @@ import org.oxycblt.auxio.home.tabs.Tab
 import org.oxycblt.auxio.list.ListSettings
 import org.oxycblt.auxio.list.adapter.UpdateInstructions
 import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
 import org.oxycblt.auxio.music.MusicType
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaySong
 import org.oxycblt.auxio.playback.PlaybackSettings
 import org.oxycblt.auxio.util.Event
 import org.oxycblt.auxio.util.MutableEvent
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -120,10 +120,6 @@ constructor(
    val playlistList: StateFlow<List<Playlist>>
        get() = _playlistList

-    private val _empty = MutableStateFlow(false)
-    val empty: StateFlow<Boolean>
-        get() = _empty
-
    private val _playlistInstructions = MutableEvent<UpdateInstructions>()
    /** Instructions for how to update [genreList] in the UI. */
    val playlistInstructions: Event<UpdateInstructions>
@ -163,10 +159,6 @@ constructor(
    val showOuter: Event<Outer>
        get() = _showOuter

-    private val _chooseMusicLocations = MutableEvent<Unit>()
-    val chooseMusicLocations: Event<Unit>
-        get() = _chooseMusicLocations
-
    init {
        homeGenerator.attach()
    }
@ -176,10 +168,6 @@ constructor(
        homeGenerator.release()
    }

-    override fun invalidateEmpty() {
-        _empty.value = homeGenerator.empty()
-    }
-
    override fun invalidateMusic(type: MusicType, instructions: UpdateInstructions) {
        when (type) {
            MusicType.SONGS -> {
@ -275,10 +263,6 @@ constructor(
        _isFastScrolling.value = isFastScrolling
    }

-    fun startChooseMusicLocations() {
-        _chooseMusicLocations.put(Unit)
-    }
-
    fun showSettings() {
        _showOuter.put(Outer.Settings)
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/ThemedSpeedDialView.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/ThemedSpeedDialView.kt
@ -190,8 +190,6 @@ class ThemedSpeedDialView : SpeedDialView {
            val overlayColor = surfaceColor.defaultColor.withModulatedAlpha(0.87f)
            overlayLayout.setBackgroundColor(overlayColor)
        }
-        // Fix default margins added by library
-        (mainFab.layoutParams as LayoutParams).setMargins(0, 0, 0, 0)
    }

    private fun Int.withModulatedAlpha(
@ -232,24 +230,13 @@ class ThemedSpeedDialView : SpeedDialView {
        return super.addActionItem(actionItem, position, animate)?.apply {
            fab.apply {
                updateLayoutParams<MarginLayoutParams> {
-                    val rightMargin = context.getDimenPixels(R.dimen.spacing_tiny)
-                    if (position == actionItems.lastIndex) {
-                        val bottomMargin = context.getDimenPixels(R.dimen.spacing_small)
-                        setMargins(0, 0, rightMargin, bottomMargin)
-                    } else {
-                        setMargins(0, 0, rightMargin, 0)
-                    }
+                    val horizontalMargin = context.getDimenPixels(R.dimen.spacing_mid_large)
+                    setMargins(horizontalMargin, 0, horizontalMargin, 0)
                }
                useCompatPadding = false
            }

            labelBackground.apply {
-                updateLayoutParams<MarginLayoutParams> {
-                    if (position == actionItems.lastIndex) {
-                        val bottomMargin = context.getDimenPixels(R.dimen.spacing_small)
-                        setMargins(0, 0, rightMargin, bottomMargin)
-                    }
-                }
                useCompatPadding = false
                setContentPadding(spacingSmall, spacingSmall, spacingSmall, spacingSmall)
                background =
--- a/app/src/main/java/org/oxycblt/auxio/home/list/AlbumListFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/list/AlbumListFragment.kt
@ -22,8 +22,6 @@ import android.os.Bundle
 import android.text.format.DateUtils
 import android.view.LayoutInflater
 import android.view.ViewGroup
-import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.activityViewModels
 import dagger.hilt.android.AndroidEntryPoint
 import java.util.Formatter
@ -38,16 +36,15 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.recycler.AlbumViewHolder
 import org.oxycblt.auxio.list.recycler.FastScrollRecyclerView
 import org.oxycblt.auxio.list.sort.Sort
-import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.formatDurationMs
+import org.oxycblt.auxio.playback.secsToMs
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song

 /**
 * A [ListFragment] that shows a list of [Album]s.
@ -82,16 +79,7 @@ class AlbumListFragment :
            listener = this@AlbumListFragment
        }

-        binding.homeNoMusicPlaceholder.apply {
-            setImageResource(R.drawable.ic_album_48)
-            contentDescription = getString(R.string.lbl_albums)
-        }
-        binding.homeNoMusicMsg.text = getString(R.string.lng_empty_albums)
-
-        binding.homeNoMusicAction.setOnClickListener { homeModel.startChooseMusicLocations() }
-
        collectImmediately(homeModel.albumList, ::updateAlbums)
-        collectImmediately(homeModel.empty, musicModel.indexingState, ::updateNoMusicIndicator)
        collectImmediately(listModel.selected, ::updateSelection)
        collectImmediately(
            playbackModel.song, playbackModel.parent, playbackModel.isPlaying, ::updatePlayback)
@ -111,10 +99,10 @@ class AlbumListFragment :
        // Change how we display the popup depending on the current sort mode.
        return when (homeModel.albumSort.mode) {
            // By Name -> Use Name
-            is Sort.Mode.ByName -> album.name.thumb()
+            is Sort.Mode.ByName -> album.name.thumb

            // By Artist -> Use name of first artist
-            is Sort.Mode.ByArtist -> album.artists[0].name.thumb()
+            is Sort.Mode.ByArtist -> album.artists[0].name.thumb

            // Date -> Use minimum date (Maximum dates are not sorted by, so showing them is odd)
            is Sort.Mode.ByDate -> album.dates?.run { min.resolve(requireContext()) }
@ -127,7 +115,7 @@ class AlbumListFragment :

            // Last added -> Format as date
            is Sort.Mode.ByDateAdded -> {
-                val dateAddedMillis = album.addedMs
+                val dateAddedMillis = album.dateAdded.secsToMs()
                formatterSb.setLength(0)
                DateUtils.formatDateRange(
                        context,
@ -159,14 +147,6 @@ class AlbumListFragment :
        albumAdapter.update(albums, homeModel.albumInstructions.consume())
    }

-    private fun updateNoMusicIndicator(empty: Boolean, indexingState: IndexingState?) {
-        val binding = requireBinding()
-        binding.homeRecycler.isInvisible = empty
-        binding.homeNoMusic.isInvisible = !empty
-        binding.homeNoMusicAction.isVisible =
-            indexingState == null || (empty && indexingState is IndexingState.Completed)
-    }
-
    private fun updateSelection(selection: List<Music>) {
        albumAdapter.setSelected(selection.filterIsInstanceTo(mutableSetOf()))
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/list/ArtistListFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/list/ArtistListFragment.kt
@ -21,8 +21,6 @@ package org.oxycblt.auxio.home.list
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.ViewGroup
-import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.activityViewModels
 import dagger.hilt.android.AndroidEntryPoint
 import org.oxycblt.auxio.R
@ -36,16 +34,15 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.recycler.ArtistViewHolder
 import org.oxycblt.auxio.list.recycler.FastScrollRecyclerView
 import org.oxycblt.auxio.list.sort.Sort
-import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.formatDurationMs
 import org.oxycblt.auxio.util.collectImmediately
 import org.oxycblt.auxio.util.positiveOrNull
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song

 /**
 * A [ListFragment] that shows a list of [Artist]s.
@ -77,16 +74,7 @@ class ArtistListFragment :
            listener = this@ArtistListFragment
        }

-        binding.homeNoMusicPlaceholder.apply {
-            setImageResource(R.drawable.ic_artist_48)
-            contentDescription = getString(R.string.lbl_artists)
-        }
-        binding.homeNoMusicMsg.text = getString(R.string.lng_empty_artists)
-
-        binding.homeNoMusicAction.setOnClickListener { homeModel.startChooseMusicLocations() }
-
        collectImmediately(homeModel.artistList, ::updateArtists)
-        collectImmediately(homeModel.empty, musicModel.indexingState, ::updateNoMusicIndicator)
        collectImmediately(listModel.selected, ::updateSelection)
        collectImmediately(
            playbackModel.song, playbackModel.parent, playbackModel.isPlaying, ::updatePlayback)
@ -106,7 +94,7 @@ class ArtistListFragment :
        // Change how we display the popup depending on the current sort mode.
        return when (homeModel.artistSort.mode) {
            // By Name -> Use Name
-            is Sort.Mode.ByName -> artist.name.thumb()
+            is Sort.Mode.ByName -> artist.name.thumb

            // Duration -> Use formatted duration
            is Sort.Mode.ByDuration -> artist.durationMs?.formatDurationMs(false)
@ -135,14 +123,6 @@ class ArtistListFragment :
        artistAdapter.update(artists, homeModel.artistInstructions.consume())
    }

-    private fun updateNoMusicIndicator(empty: Boolean, indexingState: IndexingState?) {
-        val binding = requireBinding()
-        binding.homeRecycler.isInvisible = empty
-        binding.homeNoMusic.isInvisible = !empty
-        binding.homeNoMusicAction.isVisible =
-            indexingState == null || (empty && indexingState is IndexingState.Completed)
-    }
-
    private fun updateSelection(selection: List<Music>) {
        artistAdapter.setSelected(selection.filterIsInstanceTo(mutableSetOf()))
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/list/GenreListFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/list/GenreListFragment.kt
@ -21,8 +21,6 @@ package org.oxycblt.auxio.home.list
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.ViewGroup
-import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.activityViewModels
 import dagger.hilt.android.AndroidEntryPoint
 import org.oxycblt.auxio.R
@ -36,15 +34,14 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.recycler.FastScrollRecyclerView
 import org.oxycblt.auxio.list.recycler.GenreViewHolder
 import org.oxycblt.auxio.list.sort.Sort
-import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.formatDurationMs
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song

 /**
 * A [ListFragment] that shows a list of [Genre]s.
@ -76,16 +73,7 @@ class GenreListFragment :
            listener = this@GenreListFragment
        }

-        binding.homeNoMusicPlaceholder.apply {
-            setImageResource(R.drawable.ic_genre_48)
-            contentDescription = getString(R.string.lbl_genres)
-        }
-        binding.homeNoMusicMsg.text = getString(R.string.lng_empty_genres)
-
-        binding.homeNoMusicAction.setOnClickListener { homeModel.startChooseMusicLocations() }
-
        collectImmediately(homeModel.genreList, ::updateGenres)
-        collectImmediately(homeModel.empty, musicModel.indexingState, ::updateNoMusicIndicator)
        collectImmediately(listModel.selected, ::updateSelection)
        collectImmediately(
            playbackModel.song, playbackModel.parent, playbackModel.isPlaying, ::updatePlayback)
@ -105,7 +93,7 @@ class GenreListFragment :
        // Change how we display the popup depending on the current sort mode.
        return when (homeModel.genreSort.mode) {
            // By Name -> Use Name
-            is Sort.Mode.ByName -> genre.name.thumb()
+            is Sort.Mode.ByName -> genre.name.thumb

            // Duration -> Use formatted duration
            is Sort.Mode.ByDuration -> genre.durationMs.formatDurationMs(false)
@ -134,14 +122,6 @@ class GenreListFragment :
        genreAdapter.update(genres, homeModel.genreInstructions.consume())
    }

-    private fun updateNoMusicIndicator(empty: Boolean, indexingState: IndexingState?) {
-        val binding = requireBinding()
-        binding.homeRecycler.isInvisible = empty
-        binding.homeNoMusic.isInvisible = !empty
-        binding.homeNoMusicAction.isVisible =
-            indexingState == null || (empty && indexingState is IndexingState.Completed)
-    }
-
    private fun updateSelection(selection: List<Music>) {
        genreAdapter.setSelected(selection.filterIsInstanceTo(mutableSetOf()))
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/list/ListUtil.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/list/ListUtil.kt
@ -1,31 +0,0 @@
-/*
- * Copyright (c) 2024 Auxio Project
- * ListUtil.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.home.list
-
-import androidx.core.text.isDigitsOnly
-import org.oxycblt.musikr.tag.Name
-
-fun Name.thumb() =
-    when (this) {
-        is Name.Known ->
-            tokens.firstOrNull()?.let {
-                if (it.value.isDigitsOnly()) "#" else it.value.first().uppercase()
-            }
-        is Name.Unknown -> "?"
-    }
--- a/app/src/main/java/org/oxycblt/auxio/home/list/PlaylistListFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/list/PlaylistListFragment.kt
@ -21,8 +21,6 @@ package org.oxycblt.auxio.home.list
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.ViewGroup
-import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.activityViewModels
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentHomeListBinding
@ -35,15 +33,14 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.recycler.FastScrollRecyclerView
 import org.oxycblt.auxio.list.recycler.PlaylistViewHolder
 import org.oxycblt.auxio.list.sort.Sort
-import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.formatDurationMs
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song

 /**
 * A [ListFragment] that shows a list of [Playlist]s.
@ -74,18 +71,7 @@ class PlaylistListFragment :
            listener = this@PlaylistListFragment
        }

-        binding.homeNoMusicPlaceholder.apply {
-            setImageResource(R.drawable.ic_playlist_48)
-            contentDescription = getString(R.string.lbl_playlists)
-        }
-        binding.homeNoMusicMsg.text = getString(R.string.lng_empty_playlists)
-
        collectImmediately(homeModel.playlistList, ::updatePlaylists)
-        collectImmediately(
-            homeModel.empty,
-            homeModel.playlistList,
-            musicModel.indexingState,
-            ::updateNoMusicIndicator)
        collectImmediately(listModel.selected, ::updateSelection)
        collectImmediately(
            playbackModel.song, playbackModel.parent, playbackModel.isPlaying, ::updatePlayback)
@ -105,7 +91,7 @@ class PlaylistListFragment :
        // Change how we display the popup depending on the current sort mode.
        return when (homeModel.playlistSort.mode) {
            // By Name -> Use Name
-            is Sort.Mode.ByName -> playlist.name.thumb()
+            is Sort.Mode.ByName -> playlist.name.thumb

            // Duration -> Use formatted duration
            is Sort.Mode.ByDuration -> playlist.durationMs.formatDurationMs(false)
@ -134,26 +120,6 @@ class PlaylistListFragment :
        playlistAdapter.update(playlists, homeModel.playlistInstructions.consume())
    }

-    private fun updateNoMusicIndicator(
-        empty: Boolean,
-        playlists: List<Playlist>,
-        indexingState: IndexingState?
-    ) {
-        val binding = requireBinding()
-        binding.homeRecycler.isInvisible = empty
-        binding.homeNoMusic.isInvisible = !empty && playlists.isNotEmpty()
-        if (!empty && playlists.isEmpty()) {
-            binding.homeNoMusicAction.isVisible = true
-            binding.homeNoMusicAction.text = getString(R.string.lbl_new_playlist)
-            binding.homeNoMusicAction.setOnClickListener { musicModel.createPlaylist() }
-        } else {
-            binding.homeNoMusicAction.isVisible =
-                indexingState == null || (empty && indexingState is IndexingState.Completed)
-            binding.homeNoMusicAction.text = getString(R.string.lbl_music_sources)
-            binding.homeNoMusicAction.setOnClickListener { homeModel.startChooseMusicLocations() }
-        }
-    }
-
    private fun updateSelection(selection: List<Music>) {
        playlistAdapter.setSelected(selection.filterIsInstanceTo(mutableSetOf()))
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/list/SongListFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/list/SongListFragment.kt
@ -22,8 +22,6 @@ import android.os.Bundle
 import android.text.format.DateUtils
 import android.view.LayoutInflater
 import android.view.ViewGroup
-import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.activityViewModels
 import dagger.hilt.android.AndroidEntryPoint
 import java.util.Formatter
@ -37,15 +35,14 @@ import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.recycler.FastScrollRecyclerView
 import org.oxycblt.auxio.list.recycler.SongViewHolder
 import org.oxycblt.auxio.list.sort.Sort
-import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.formatDurationMs
+import org.oxycblt.auxio.playback.secsToMs
 import org.oxycblt.auxio.util.collectImmediately
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Song

 /**
 * A [ListFragment] that shows a list of [Song]s.
@ -62,7 +59,6 @@ class SongListFragment :
    override val musicModel: MusicViewModel by activityViewModels()
    override val playbackModel: PlaybackViewModel by activityViewModels()
    private val songAdapter = SongAdapter(this)
-
    // Save memory by re-using the same formatter and string builder when creating popup text
    private val formatterSb = StringBuilder(64)
    private val formatter = Formatter(formatterSb)
@ -80,16 +76,7 @@ class SongListFragment :
            listener = this@SongListFragment
        }

-        binding.homeNoMusicPlaceholder.apply {
-            setImageResource(R.drawable.ic_song_48)
-            contentDescription = getString(R.string.lbl_songs)
-        }
-        binding.homeNoMusicMsg.text = getString(R.string.lng_empty_songs)
-
-        binding.homeNoMusicAction.setOnClickListener { homeModel.startChooseMusicLocations() }
-
        collectImmediately(homeModel.songList, ::updateSongs)
-        collectImmediately(homeModel.empty, musicModel.indexingState, ::updateNoMusicIndicator)
        collectImmediately(listModel.selected, ::updateSelection)
        collectImmediately(
            playbackModel.song, playbackModel.parent, playbackModel.isPlaying, ::updatePlayback)
@ -111,23 +98,23 @@ class SongListFragment :
        // based off the names of the parent objects and not the child objects.
        return when (homeModel.songSort.mode) {
            // Name -> Use name
-            is Sort.Mode.ByName -> song.name.thumb()
+            is Sort.Mode.ByName -> song.name.thumb

            // Artist -> Use name of first artist
-            is Sort.Mode.ByArtist -> song.album.artists[0].name.thumb()
+            is Sort.Mode.ByArtist -> song.album.artists[0].name.thumb

            // Album -> Use Album Name
-            is Sort.Mode.ByAlbum -> song.album.name.thumb()
+            is Sort.Mode.ByAlbum -> song.album.name.thumb

            // Year -> Use Full Year
-            is Sort.Mode.ByDate -> song.album.dates?.resolve(requireContext())
+            is Sort.Mode.ByDate -> song.album.dates?.resolveDate(requireContext())

            // Duration -> Use formatted duration
            is Sort.Mode.ByDuration -> song.durationMs.formatDurationMs(false)

            // Last added -> Format as date
            is Sort.Mode.ByDateAdded -> {
-                val dateAddedMillis = song.addedMs
+                val dateAddedMillis = song.dateAdded.secsToMs()
                formatterSb.setLength(0)
                DateUtils.formatDateRange(
                        context,
@ -159,14 +146,6 @@ class SongListFragment :
        songAdapter.update(songs, homeModel.songInstructions.consume())
    }

-    private fun updateNoMusicIndicator(empty: Boolean, indexingState: IndexingState?) {
-        val binding = requireBinding()
-        binding.homeRecycler.isInvisible = empty
-        binding.homeNoMusic.isInvisible = !empty
-        binding.homeNoMusicAction.isVisible =
-            indexingState == null || (empty && indexingState is IndexingState.Completed)
-    }
-
    private fun updateSelection(selection: List<Music>) {
        songAdapter.setSelected(selection.filterIsInstanceTo(mutableSetOf()))
    }
--- a/app/src/main/java/org/oxycblt/auxio/home/tabs/AdaptiveTabStrategy.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/tabs/AdaptiveTabStrategy.kt
@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2022 Auxio Project
+ * AdaptiveTabStrategy.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.home.tabs
+
+import android.content.Context
+import com.google.android.material.tabs.TabLayout
+import com.google.android.material.tabs.TabLayoutMediator
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.music.MusicType
+
+/**
+ * A [TabLayoutMediator.TabConfigurationStrategy] that uses larger/smaller tab configurations
+ * depending on the screen configuration.
+ *
+ * @param context [Context] required to obtain window information
+ * @param tabs Current tab configuration from settings
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class AdaptiveTabStrategy(context: Context, private val tabs: List<MusicType>) :
+    TabLayoutMediator.TabConfigurationStrategy {
+    private val width = context.resources.configuration.smallestScreenWidthDp
+
+    override fun onConfigureTab(tab: TabLayout.Tab, position: Int) {
+        val homeTab = tabs[position]
+        val icon =
+            when (homeTab) {
+                MusicType.SONGS -> R.drawable.ic_song_24
+                MusicType.ALBUMS -> R.drawable.ic_album_24
+                MusicType.ARTISTS -> R.drawable.ic_artist_24
+                MusicType.GENRES -> R.drawable.ic_genre_24
+                MusicType.PLAYLISTS -> R.drawable.ic_playlist_24
+            }
+
+        // Use expected sw* size thresholds when choosing a configuration.
+        when {
+            // On small screens, only display an icon.
+            width < 370 -> tab.setIcon(icon).setContentDescription(homeTab.nameRes)
+            // On large screens, display an icon and text.
+            width < 600 -> tab.setText(homeTab.nameRes)
+            // On medium-size screens, display text.
+            else -> tab.setIcon(icon).setText(homeTab.nameRes)
+        }
+    }
+}
--- a/app/src/main/java/org/oxycblt/auxio/home/tabs/NamedTabStrategy.kt
+++ b/app/src/main/java/org/oxycblt/auxio/home/tabs/NamedTabStrategy.kt
@ -1,29 +0,0 @@
-/*
- * Copyright (c) 2025 Auxio Project
- * NamedTabStrategy.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.home.tabs
-
-import com.google.android.material.tabs.TabLayout
-import com.google.android.material.tabs.TabLayoutMediator.TabConfigurationStrategy
-import org.oxycblt.auxio.music.MusicType
-
-class NamedTabStrategy(private val homeTabs: List<MusicType>) : TabConfigurationStrategy {
-    override fun onConfigureTab(tab: TabLayout.Tab, position: Int) {
-        tab.setText(homeTabs[position].nameRes)
-    }
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/BitmapProvider.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/BitmapProvider.kt
@ -20,14 +20,14 @@ package org.oxycblt.auxio.image

 import android.content.Context
 import android.graphics.Bitmap
-import coil3.ImageLoader
-import coil3.request.Disposable
-import coil3.request.ImageRequest
-import coil3.size.Size
-import coil3.toBitmap
+import androidx.core.graphics.drawable.toBitmap
+import coil.ImageLoader
+import coil.request.Disposable
+import coil.request.ImageRequest
+import coil.size.Size
 import dagger.hilt.android.qualifiers.ApplicationContext
 import javax.inject.Inject
-import org.oxycblt.musikr.Song
+import org.oxycblt.auxio.music.Song

 /**
 * A utility to provide bitmaps in a race-less manner.
@ -94,7 +94,7 @@ constructor(
            target
                .onConfigRequest(
                    ImageRequest.Builder(context)
-                        .data(song.cover)
+                        .data(listOf(song.cover))
                        // Use ORIGINAL sizing, as we are not loading into any View-like component.
                        .size(Size.ORIGINAL))
                .target(
--- a/app/src/main/java/org/oxycblt/auxio/image/CoverMode.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/CoverMode.kt
@ -26,11 +26,12 @@ import org.oxycblt.auxio.IntegerTable
 * @author Alexander Capehart (OxygenCobalt)
 */
 enum class CoverMode {
+    /** Do not load album covers ("Off"). */
    OFF,
-    SAVE_SPACE,
-    BALANCED,
-    HIGH_QUALITY,
-    AS_IS;
+    /** Load covers from the fast, but lower-quality media store database ("Fast"). */
+    MEDIA_STORE,
+    /** Load high-quality covers directly from music files ("Quality"). */
+    QUALITY;

    /**
     * The integer representation of this instance.
@ -41,10 +42,8 @@ enum class CoverMode {
        get() =
            when (this) {
                OFF -> IntegerTable.COVER_MODE_OFF
-                SAVE_SPACE -> IntegerTable.COVER_MODE_SAVE_SPACE
-                BALANCED -> IntegerTable.COVER_MODE_BALANCED
-                HIGH_QUALITY -> IntegerTable.COVER_MODE_HIGH_QUALITY
-                AS_IS -> IntegerTable.COVER_MODE_AS_IS
+                MEDIA_STORE -> IntegerTable.COVER_MODE_MEDIA_STORE
+                QUALITY -> IntegerTable.COVER_MODE_QUALITY
            }

    companion object {
@ -58,10 +57,8 @@ enum class CoverMode {
        fun fromIntCode(intCode: Int) =
            when (intCode) {
                IntegerTable.COVER_MODE_OFF -> OFF
-                IntegerTable.COVER_MODE_SAVE_SPACE -> SAVE_SPACE
-                IntegerTable.COVER_MODE_BALANCED -> BALANCED
-                IntegerTable.COVER_MODE_HIGH_QUALITY -> HIGH_QUALITY
-                IntegerTable.COVER_MODE_AS_IS -> AS_IS
+                IntegerTable.COVER_MODE_MEDIA_STORE -> MEDIA_STORE
+                IntegerTable.COVER_MODE_QUALITY -> QUALITY
                else -> null
            }
    }
--- a/app/src/main/java/org/oxycblt/auxio/image/CoverProvider.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/CoverProvider.kt
@ -1,86 +0,0 @@
-/*
- * Copyright (c) 2025 Auxio Project
- * CoverProvider.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image
-
-import android.content.ContentProvider
-import android.content.ContentResolver
-import android.content.ContentValues
-import android.content.UriMatcher
-import android.database.Cursor
-import android.net.Uri
-import android.os.ParcelFileDescriptor
-import kotlinx.coroutines.runBlocking
-import org.oxycblt.auxio.BuildConfig
-import org.oxycblt.auxio.image.covers.SettingCovers
-import org.oxycblt.musikr.covers.CoverResult
-
-class CoverProvider : ContentProvider() {
-    override fun onCreate(): Boolean = true
-
-    override fun openFile(uri: Uri, mode: String): ParcelFileDescriptor? {
-        if (mode != "r" || uriMatcher.match(uri) != 1) {
-            return null
-        }
-        val id = uri.lastPathSegment ?: return null
-        return runBlocking {
-            when (val result = SettingCovers.immutable(requireNotNull(context)).obtain(id)) {
-                is CoverResult.Hit -> result.cover.fd()
-                else -> null
-            }
-        }
-    }
-
-    override fun getType(uri: Uri): String {
-        check(uriMatcher.match(uri) == 1) { "Unknown URI: $uri" }
-        return "image/*"
-    }
-
-    override fun query(
-        uri: Uri,
-        projection: Array<out String>?,
-        selection: String?,
-        selectionArgs: Array<out String>?,
-        sortOrder: String?
-    ): Cursor = throw UnsupportedOperationException()
-
-    override fun insert(uri: Uri, values: ContentValues?): Uri? = null
-
-    override fun delete(uri: Uri, selection: String?, selectionArgs: Array<out String>?): Int = 0
-
-    override fun update(
-        uri: Uri,
-        values: ContentValues?,
-        selection: String?,
-        selectionArgs: Array<out String>?
-    ): Int = 0
-
-    companion object {
-        private const val AUTHORITY = "${BuildConfig.APPLICATION_ID}.image.CoverProvider"
-        private const val IMAGES_PATH = "covers"
-        private val uriMatcher =
-            UriMatcher(UriMatcher.NO_MATCH).apply { addURI(AUTHORITY, "$IMAGES_PATH/*", 1) }
-
-        val CONTENT_URI: Uri =
-            Uri.Builder()
-                .scheme(ContentResolver.SCHEME_CONTENT)
-                .authority(AUTHORITY)
-                .appendPath(IMAGES_PATH)
-                .build()
-    }
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/CoverView.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/CoverView.kt
@ -37,35 +37,31 @@ import androidx.annotation.DrawableRes
 import androidx.annotation.Px
 import androidx.core.graphics.drawable.DrawableCompat
 import androidx.core.view.children
-import androidx.core.view.isEmpty
 import androidx.core.view.updateMarginsRelative
 import androidx.core.widget.ImageViewCompat
-import coil3.ImageLoader
-import coil3.asImage
-import coil3.request.ImageRequest
-import coil3.request.target
-import coil3.request.transformations
-import coil3.util.CoilUtils
+import coil.ImageLoader
+import coil.request.ImageRequest
+import coil.util.CoilUtils
 import com.google.android.material.R as MR
 import com.google.android.material.shape.MaterialShapeDrawable
 import com.google.android.material.shape.ShapeAppearanceModel
 import dagger.hilt.android.AndroidEntryPoint
 import javax.inject.Inject
 import org.oxycblt.auxio.R
-import org.oxycblt.auxio.image.coil.RoundedRectTransformation
-import org.oxycblt.auxio.image.coil.SquareCropTransformation
+import org.oxycblt.auxio.image.extractor.Cover
+import org.oxycblt.auxio.image.extractor.RoundedRectTransformation
+import org.oxycblt.auxio.image.extractor.SquareCropTransformation
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.ui.MaterialFader
 import org.oxycblt.auxio.ui.UISettings
 import org.oxycblt.auxio.util.getAttrColorCompat
 import org.oxycblt.auxio.util.getColorCompat
 import org.oxycblt.auxio.util.getDimenPixels
 import org.oxycblt.auxio.util.getDrawableCompat
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.covers.CoverCollection

 /**
 * Auxio's extension of [ImageView] that enables cover art loading and playing indicator and
@ -173,7 +169,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
        super.onFinishInflate()

        // The image isn't added if other children have populated the body. This is by design.
-        if (isEmpty()) {
+        if (childCount == 0) {
            addView(image)
        }

@ -317,7 +313,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     */
    fun bind(song: Song) =
        bindImpl(
-            song.cover,
+            listOf(song.cover),
            context.getString(R.string.desc_album_cover, song.album.name),
            R.drawable.ic_album_24)

@ -328,7 +324,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     */
    fun bind(album: Album) =
        bindImpl(
-            album.covers,
+            album.cover.all,
            context.getString(R.string.desc_album_cover, album.name),
            R.drawable.ic_album_24)

@ -339,7 +335,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     */
    fun bind(artist: Artist) =
        bindImpl(
-            artist.covers,
+            artist.cover.all,
            context.getString(R.string.desc_artist_image, artist.name),
            R.drawable.ic_artist_24)

@ -350,7 +346,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     */
    fun bind(genre: Genre) =
        bindImpl(
-            genre.covers,
+            genre.cover.all,
            context.getString(R.string.desc_genre_image, genre.name),
            R.drawable.ic_genre_24)

@ -361,7 +357,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     */
    fun bind(playlist: Playlist) =
        bindImpl(
-            playlist.covers,
+            playlist.cover?.all ?: emptyList(),
            context.getString(R.string.desc_playlist_image, playlist.name),
            R.drawable.ic_playlist_24)

@ -373,15 +369,13 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     * @param errorRes The resource of the error drawable to use if the cover cannot be loaded.
     */
    fun bind(songs: List<Song>, desc: String, @DrawableRes errorRes: Int) =
-        bindImpl(CoverCollection.from(songs.mapNotNull { it.cover }), desc, errorRes)
+        bindImpl(Cover.order(songs), desc, errorRes)

-    private fun bindImpl(cover: Any?, desc: String, @DrawableRes errorRes: Int) {
+    private fun bindImpl(covers: List<Cover>, desc: String, @DrawableRes errorRes: Int) {
        val request =
            ImageRequest.Builder(context)
-                .data(cover)
-                .error(
-                    StyledDrawable(context, context.getDrawableCompat(errorRes), iconSize)
-                        .asImage())
+                .data(covers)
+                .error(StyledDrawable(context, context.getDrawableCompat(errorRes), iconSize))
                .target(image)

        val cornersTransformation =
@ -410,7 +404,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
        @Px val iconSize: Int?
    ) : Drawable() {
        init {
-            // Re-tint the drawable to use the analogous "on surface" color for
+            // Re-tint the drawable to use the analogous "on surfaceg" color for
            // StyledImageView.
            DrawableCompat.setTintList(inner, context.getColorCompat(R.color.sel_on_cover_bg))
        }
--- a/app/src/main/java/org/oxycblt/auxio/image/ImageSettings.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/ImageSettings.kt
@ -49,7 +49,7 @@ class ImageSettingsImpl @Inject constructor(@ApplicationContext context: Context
        get() =
            CoverMode.fromIntCode(
                sharedPreferences.getInt(getString(R.string.set_key_cover_mode), Int.MIN_VALUE))
-                ?: CoverMode.BALANCED
+                ?: CoverMode.MEDIA_STORE

    override val forceSquareCovers: Boolean
        get() = sharedPreferences.getBoolean(getString(R.string.set_key_square_covers), false)
@ -64,8 +64,8 @@ class ImageSettingsImpl @Inject constructor(@ApplicationContext context: Context
                when {
                    !sharedPreferences.getBoolean(OLD_KEY_SHOW_COVERS, true) -> CoverMode.OFF
                    !sharedPreferences.getBoolean(OLD_KEY_QUALITY_COVERS, true) ->
-                        CoverMode.BALANCED
-                    else -> CoverMode.BALANCED
+                        CoverMode.MEDIA_STORE
+                    else -> CoverMode.QUALITY
                }

            sharedPreferences.edit {
@ -74,24 +74,6 @@ class ImageSettingsImpl @Inject constructor(@ApplicationContext context: Context
                remove(OLD_KEY_QUALITY_COVERS)
            }
        }
-
-        if (sharedPreferences.contains(OLD_KEY_COVER_MODE)) {
-            L.d("Migrating cover mode setting")
-
-            var mode =
-                CoverMode.fromIntCode(sharedPreferences.getInt(OLD_KEY_COVER_MODE, Int.MIN_VALUE))
-                    ?: CoverMode.BALANCED
-            if (mode == CoverMode.HIGH_QUALITY) {
-                // High quality now has space characteristics that could be
-                // undesirable, clamp to balanced.
-                mode = CoverMode.BALANCED
-            }
-
-            sharedPreferences.edit {
-                putInt(getString(R.string.set_key_cover_mode), mode.intCode)
-                remove(OLD_KEY_COVER_MODE)
-            }
-        }
    }

    override fun onSettingChanged(key: String, listener: ImageSettings.Listener) {
@ -105,6 +87,5 @@ class ImageSettingsImpl @Inject constructor(@ApplicationContext context: Context
    private companion object {
        const val OLD_KEY_SHOW_COVERS = "KEY_SHOW_COVERS"
        const val OLD_KEY_QUALITY_COVERS = "KEY_QUALITY_COVERS"
-        const val OLD_KEY_COVER_MODE = "auxio_cover_mode"
    }
 }
--- a/app/src/main/java/org/oxycblt/auxio/image/coil/CoverCollectionFetcher.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/coil/CoverCollectionFetcher.kt
@ -1,140 +0,0 @@
-/*
- * Copyright (c) 2024 Auxio Project
- * CoverCollectionFetcher.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image.coil
-
-import android.content.Context
-import android.graphics.BitmapFactory
-import android.graphics.Canvas
-import androidx.core.graphics.createBitmap
-import androidx.core.graphics.drawable.toDrawable
-import coil3.ImageLoader
-import coil3.asImage
-import coil3.decode.DataSource
-import coil3.decode.ImageSource
-import coil3.fetch.FetchResult
-import coil3.fetch.Fetcher
-import coil3.fetch.ImageFetchResult
-import coil3.fetch.SourceFetchResult
-import coil3.request.Options
-import coil3.size.Dimension
-import coil3.size.Size
-import coil3.size.pxOrElse
-import java.io.InputStream
-import javax.inject.Inject
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.flow.asFlow
-import kotlinx.coroutines.flow.mapNotNull
-import kotlinx.coroutines.flow.take
-import kotlinx.coroutines.flow.toList
-import kotlinx.coroutines.withContext
-import okio.FileSystem
-import okio.buffer
-import okio.source
-import org.oxycblt.musikr.covers.CoverCollection
-
-class CoverCollectionFetcher
-private constructor(
-    private val context: Context,
-    private val covers: CoverCollection,
-    private val size: Size,
-) : Fetcher {
-    override suspend fun fetch(): FetchResult? {
-        val streams = covers.covers.asFlow().mapNotNull { it.open() }.take(4).toList()
-        // We don't immediately check for mosaic feasibility from album count alone, as that
-        // does not factor in InputStreams failing to load. Instead, only check once we
-        // definitely have image data to use.
-        if (streams.size == 4) {
-            // Make sure we free the InputStreams once we've transformed them into a
-            // mosaic.
-            return createMosaic(streams, size).also {
-                withContext(Dispatchers.IO) { streams.forEach(InputStream::close) }
-            }
-        }
-
-        // Not enough covers for a mosaic, take the first one (if that even exists)
-        val first = streams.firstOrNull() ?: return null
-
-        // All but the first stream will be unused, free their resources
-        withContext(Dispatchers.IO) {
-            for (i in 1 until streams.size) {
-                streams[i].close()
-            }
-        }
-
-        return SourceFetchResult(
-            source = ImageSource(first.source().buffer(), FileSystem.SYSTEM, null),
-            mimeType = null,
-            dataSource = DataSource.DISK)
-    }
-
-    /** Derived from phonograph: https://github.com/kabouzeid/Phonograph */
-    private suspend fun createMosaic(streams: List<InputStream>, size: Size): FetchResult {
-        // Use whatever size coil gives us to create the mosaic.
-        val mosaicSize = android.util.Size(size.width.mosaicSize(), size.height.mosaicSize())
-        val mosaicFrameSize =
-            Size(Dimension(mosaicSize.width / 2), Dimension(mosaicSize.height / 2))
-
-        val mosaicBitmap = createBitmap(mosaicSize.width, mosaicSize.height)
-        val canvas = Canvas(mosaicBitmap)
-
-        var x = 0
-        var y = 0
-
-        // For each stream, create a bitmap scaled to 1/4th of the mosaics combined size
-        // and place it on a corner of the canvas.
-        for (stream in streams) {
-            if (y == mosaicSize.height) {
-                break
-            }
-
-            // Crop the bitmap down to a square so it leaves no empty space
-            // TODO: Work around this
-            val bitmap =
-                SquareCropTransformation.INSTANCE.transform(
-                    BitmapFactory.decodeStream(stream), mosaicFrameSize)
-            canvas.drawBitmap(bitmap, x.toFloat(), y.toFloat(), null)
-
-            x += bitmap.width
-            if (x == mosaicSize.width) {
-                x = 0
-                y += bitmap.height
-            }
-        }
-
-        // It's way easier to map this into a drawable then try to serialize it into an
-        // BufferedSource. Just make sure we mark it as "sampled" so Coil doesn't try to
-        // load low-res mosaics into high-res ImageViews.
-        return ImageFetchResult(
-            image = mosaicBitmap.toDrawable(context.resources).asImage(),
-            isSampled = true,
-            dataSource = DataSource.DISK)
-    }
-
-    private fun Dimension.mosaicSize(): Int {
-        // Since we want the mosaic to be perfectly divisible into two, we need to round any
-        // odd image sizes upwards to prevent the mosaic creation from failing.
-        val size = pxOrElse { 512 }
-        return if (size.mod(2) > 0) size + 1 else size
-    }
-
-    class Factory @Inject constructor() : Fetcher.Factory<CoverCollection> {
-        override fun create(data: CoverCollection, options: Options, imageLoader: ImageLoader) =
-            CoverCollectionFetcher(options.context, data, options.size)
-    }
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/coil/CoverFetcher.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/coil/CoverFetcher.kt
@ -1,47 +0,0 @@
-/*
- * Copyright (c) 2024 Auxio Project
- * CoverFetcher.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image.coil
-
-import coil3.ImageLoader
-import coil3.decode.DataSource
-import coil3.decode.ImageSource
-import coil3.fetch.FetchResult
-import coil3.fetch.Fetcher
-import coil3.fetch.SourceFetchResult
-import coil3.request.Options
-import javax.inject.Inject
-import okio.FileSystem
-import okio.buffer
-import okio.source
-import org.oxycblt.musikr.covers.Cover
-
-class CoverFetcher private constructor(private val cover: Cover) : Fetcher {
-    override suspend fun fetch(): FetchResult? {
-        val stream = cover.open() ?: return null
-        return SourceFetchResult(
-            source = ImageSource(stream.source().buffer(), FileSystem.SYSTEM, null),
-            mimeType = null,
-            dataSource = DataSource.DISK)
-    }
-
-    class Factory @Inject constructor() : Fetcher.Factory<Cover> {
-        override fun create(data: Cover, options: Options, imageLoader: ImageLoader) =
-            CoverFetcher(data)
-    }
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/coil/Keyers.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/coil/Keyers.kt
@ -1,34 +0,0 @@
-/*
- * Copyright (c) 2021 Auxio Project
- * Keyers.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image.coil
-
-import coil3.key.Keyer
-import coil3.request.Options
-import javax.inject.Inject
-import org.oxycblt.musikr.covers.Cover
-import org.oxycblt.musikr.covers.CoverCollection
-
-class CoverKeyer @Inject constructor() : Keyer<Cover> {
-    override fun key(data: Cover, options: Options) = "${data.id}&${options.size}"
-}
-
-class CoverCollectionKeyer @Inject constructor() : Keyer<CoverCollection> {
-    override fun key(data: CoverCollection, options: Options) =
-        "multi:${data.hashCode()}&${options.size}"
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/covers/NullCovers.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/covers/NullCovers.kt
@ -1,42 +0,0 @@
-/*
- * Copyright (c) 2024 Auxio Project
- * NullCovers.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image.covers
-
-import org.oxycblt.musikr.covers.Cover
-import org.oxycblt.musikr.covers.CoverResult
-import org.oxycblt.musikr.covers.MutableCovers
-import org.oxycblt.musikr.covers.stored.CoverStorage
-import org.oxycblt.musikr.fs.device.DeviceFile
-import org.oxycblt.musikr.metadata.Metadata
-
-class NullCovers(private val storage: CoverStorage) : MutableCovers<NullCover> {
-    override suspend fun obtain(id: String) = CoverResult.Hit(NullCover)
-
-    override suspend fun create(file: DeviceFile, metadata: Metadata) = CoverResult.Hit(NullCover)
-
-    override suspend fun cleanup(excluding: Collection<Cover>) {
-        storage.ls(setOf()).map { storage.rm(it) }
-    }
-}
-
-data object NullCover : Cover {
-    override val id = "null"
-
-    override suspend fun open() = null
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/covers/RevisionedTranscoding.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/covers/RevisionedTranscoding.kt
@ -1,26 +0,0 @@
-/*
- * Copyright (c) 2025 Auxio Project
- * RevisionedTranscoding.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image.covers
-
-import java.util.UUID
-import org.oxycblt.musikr.covers.stored.Transcoding
-
-class RevisionedTranscoding(revision: UUID, private val inner: Transcoding) : Transcoding by inner {
-    override val tag = "_$revision${inner.tag}"
-}
--- a/app/src/main/java/org/oxycblt/auxio/image/covers/SettingCovers.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/covers/SettingCovers.kt
@ -1,73 +0,0 @@
-/*
- * Copyright (c) 2024 Auxio Project
- * SettingCovers.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.image.covers
-
-import android.content.Context
-import android.graphics.Bitmap
-import java.util.UUID
-import javax.inject.Inject
-import org.oxycblt.auxio.image.CoverMode
-import org.oxycblt.auxio.image.ImageSettings
-import org.oxycblt.musikr.covers.Cover
-import org.oxycblt.musikr.covers.Covers
-import org.oxycblt.musikr.covers.FDCover
-import org.oxycblt.musikr.covers.MutableCovers
-import org.oxycblt.musikr.covers.chained.ChainedCovers
-import org.oxycblt.musikr.covers.chained.MutableChainedCovers
-import org.oxycblt.musikr.covers.embedded.CoverIdentifier
-import org.oxycblt.musikr.covers.embedded.EmbeddedCovers
-import org.oxycblt.musikr.covers.fs.FSCovers
-import org.oxycblt.musikr.covers.fs.MutableFSCovers
-import org.oxycblt.musikr.covers.stored.Compress
-import org.oxycblt.musikr.covers.stored.CoverStorage
-import org.oxycblt.musikr.covers.stored.MutableStoredCovers
-import org.oxycblt.musikr.covers.stored.NoTranscoding
-import org.oxycblt.musikr.covers.stored.StoredCovers
-
-interface SettingCovers {
-    suspend fun mutate(context: Context, revision: UUID): MutableCovers<out Cover>
-
-    companion object {
-        suspend fun immutable(context: Context): Covers<FDCover> =
-            ChainedCovers(StoredCovers(CoverStorage.at(context.coversDir())), FSCovers(context))
-    }
-}
-
-class SettingCoversImpl @Inject constructor(private val imageSettings: ImageSettings) :
-    SettingCovers {
-    override suspend fun mutate(context: Context, revision: UUID): MutableCovers<out Cover> {
-        val coverStorage = CoverStorage.at(context.coversDir())
-        val transcoding =
-            when (imageSettings.coverMode) {
-                CoverMode.OFF -> return NullCovers(coverStorage)
-                CoverMode.SAVE_SPACE -> Compress(Bitmap.CompressFormat.JPEG, 500, 70)
-                CoverMode.BALANCED -> Compress(Bitmap.CompressFormat.JPEG, 750, 85)
-                CoverMode.HIGH_QUALITY -> Compress(Bitmap.CompressFormat.JPEG, 1000, 100)
-                CoverMode.AS_IS -> NoTranscoding
-            }
-        val revisionedTranscoding = RevisionedTranscoding(revision, transcoding)
-        val storedCovers =
-            MutableStoredCovers(
-                EmbeddedCovers(CoverIdentifier.md5()), coverStorage, revisionedTranscoding)
-        val fsCovers = MutableFSCovers(context)
-        return MutableChainedCovers(storedCovers, fsCovers)
-    }
-}
-
-private fun Context.coversDir() = filesDir.resolve("covers").apply { mkdirs() }
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/Components.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/Components.kt
@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2021 Auxio Project
+ * Components.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.image.extractor
+
+import coil.ImageLoader
+import coil.fetch.Fetcher
+import coil.key.Keyer
+import coil.request.Options
+import coil.size.Size
+import javax.inject.Inject
+
+class CoverKeyer @Inject constructor() : Keyer<Collection<Cover>> {
+    override fun key(data: Collection<Cover>, options: Options) =
+        "${data.map { it.key }.hashCode()}"
+}
+
+class CoverFetcher
+private constructor(
+    private val covers: Collection<Cover>,
+    private val size: Size,
+    private val coverExtractor: CoverExtractor,
+) : Fetcher {
+    override suspend fun fetch() = coverExtractor.extract(covers, size)
+
+    class Factory @Inject constructor(private val coverExtractor: CoverExtractor) :
+        Fetcher.Factory<Collection<Cover>> {
+        override fun create(data: Collection<Cover>, options: Options, imageLoader: ImageLoader) =
+            CoverFetcher(data, options.size, coverExtractor)
+    }
+}
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/Cover.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/Cover.kt
@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * Cover.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.image.extractor
+
+import android.net.Uri
+import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Song
+
+sealed interface Cover {
+    val key: String
+    val mediaStoreCoverUri: Uri
+
+    /**
+     * The song has an embedded cover art we support, so we can operate with it on a per-song basis.
+     */
+    data class Embedded(val songCoverUri: Uri, val songUri: Uri, val perceptualHash: String) :
+        Cover {
+        override val mediaStoreCoverUri = songCoverUri
+        override val key = perceptualHash
+    }
+
+    /**
+     * We couldn't find any embedded cover art ourselves, but the android system might have some
+     * through a cover.jpg file or something similar.
+     */
+    data class External(val albumCoverUri: Uri) : Cover {
+        override val mediaStoreCoverUri = albumCoverUri
+        override val key = albumCoverUri.toString()
+    }
+
+    companion object {
+        private val FALLBACK_SORT = Sort(Sort.Mode.ByAlbum, Sort.Direction.ASCENDING)
+
+        fun order(songs: Collection<Song>) =
+            FALLBACK_SORT.songs(songs)
+                .map { it.cover }
+                .groupBy { it.key }
+                .entries
+                .sortedByDescending { it.value.size }
+                .map { it.value.first() }
+    }
+}
+
+data class ParentCover(val single: Cover, val all: List<Cover>) {
+    companion object {
+        fun from(song: Song, songs: Collection<Song>) = from(song.cover, songs)
+
+        fun from(src: Cover, songs: Collection<Song>) = ParentCover(src, Cover.order(songs))
+    }
+}
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/CoverExtractor.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/CoverExtractor.kt
@ -0,0 +1,253 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * CoverExtractor.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.image.extractor
+
+import android.annotation.SuppressLint
+import android.content.Context
+import android.graphics.Bitmap
+import android.graphics.BitmapFactory
+import android.graphics.Canvas
+import android.media.MediaMetadataRetriever
+import android.util.Size as AndroidSize
+import androidx.core.graphics.drawable.toDrawable
+import androidx.media3.common.MediaItem
+import androidx.media3.common.MediaMetadata
+import androidx.media3.common.Metadata
+import androidx.media3.exoplayer.MetadataRetriever
+import androidx.media3.exoplayer.source.MediaSource
+import androidx.media3.extractor.metadata.flac.PictureFrame
+import androidx.media3.extractor.metadata.id3.ApicFrame
+import coil.decode.DataSource
+import coil.decode.ImageSource
+import coil.fetch.DrawableResult
+import coil.fetch.FetchResult
+import coil.fetch.SourceResult
+import coil.size.Dimension
+import coil.size.Size
+import coil.size.pxOrElse
+import dagger.hilt.android.qualifiers.ApplicationContext
+import java.io.ByteArrayInputStream
+import java.io.InputStream
+import javax.inject.Inject
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.guava.asDeferred
+import kotlinx.coroutines.withContext
+import okio.buffer
+import okio.source
+import org.oxycblt.auxio.image.CoverMode
+import org.oxycblt.auxio.image.ImageSettings
+import org.oxycblt.auxio.music.Song
+import timber.log.Timber as L
+
+/**
+ * Provides functionality for extracting album cover information. Meant for internal use only.
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class CoverExtractor
+@Inject
+constructor(
+    @ApplicationContext private val context: Context,
+    private val imageSettings: ImageSettings,
+    private val mediaSourceFactory: MediaSource.Factory
+) {
+    /**
+     * Extract an image (in the form of [FetchResult]) to represent the given [Song]s.
+     *
+     * @param covers The [Cover]s to load.
+     * @param size The [Size] of the image to load.
+     * @return If four distinct album covers could be extracted from the [Song]s, a [DrawableResult]
+     *   will be returned of a mosaic composed of the first four loaded album covers. Otherwise, a
+     *   [SourceResult] of one album cover will be returned.
+     */
+    suspend fun extract(covers: Collection<Cover>, size: Size): FetchResult? {
+        val streams = mutableListOf<InputStream>()
+        for (cover in covers) {
+            openCoverInputStream(cover)?.let(streams::add)
+            // We don't immediately check for mosaic feasibility from album count alone, as that
+            // does not factor in InputStreams failing to load. Instead, only check once we
+            // definitely have image data to use.
+            if (streams.size == 4) {
+                // Make sure we free the InputStreams once we've transformed them into a mosaic.
+                return createMosaic(streams, size).also {
+                    withContext(Dispatchers.IO) { streams.forEach(InputStream::close) }
+                }
+            }
+        }
+
+        // Not enough covers for a mosaic, take the first one (if that even exists)
+        val first = streams.firstOrNull() ?: return null
+
+        // All but the first stream will be unused, free their resources
+        withContext(Dispatchers.IO) {
+            for (i in 1 until streams.size) {
+                streams[i].close()
+            }
+        }
+
+        return SourceResult(
+            source = ImageSource(first.source().buffer(), context),
+            mimeType = null,
+            dataSource = DataSource.DISK)
+    }
+
+    fun findCoverDataInMetadata(metadata: Metadata): InputStream? {
+        var stream: ByteArrayInputStream? = null
+
+        for (i in 0 until metadata.length()) {
+            // We can only extract pictures from two tags with this method, ID3v2's APIC or
+            // Vorbis picture comments.
+            val pic: ByteArray?
+            val type: Int
+
+            when (val entry = metadata.get(i)) {
+                is ApicFrame -> {
+                    pic = entry.pictureData
+                    type = entry.pictureType
+                }
+                is PictureFrame -> {
+                    pic = entry.pictureData
+                    type = entry.pictureType
+                }
+                else -> continue
+            }
+
+            if (type == MediaMetadata.PICTURE_TYPE_FRONT_COVER) {
+                stream = ByteArrayInputStream(pic)
+                break
+            } else if (stream == null) {
+                stream = ByteArrayInputStream(pic)
+            }
+        }
+
+        return stream
+    }
+
+    private suspend fun openCoverInputStream(cover: Cover) =
+        try {
+            when (cover) {
+                is Cover.Embedded ->
+                    when (imageSettings.coverMode) {
+                        CoverMode.OFF -> null
+                        CoverMode.MEDIA_STORE -> extractMediaStoreCover(cover)
+                        CoverMode.QUALITY -> extractQualityCover(cover)
+                    }
+                is Cover.External -> {
+                    extractMediaStoreCover(cover)
+                }
+            }
+        } catch (e: Exception) {
+            L.e("Unable to extract album cover due to an error: $e")
+            null
+        }
+
+    private suspend fun extractQualityCover(cover: Cover.Embedded) =
+        extractExoplayerCover(cover)
+            ?: extractAospMetadataCover(cover)
+            ?: extractMediaStoreCover(cover)
+
+    private fun extractAospMetadataCover(cover: Cover.Embedded): InputStream? =
+        MediaMetadataRetriever().run {
+            // This call is time-consuming but it also doesn't seem to hold up the main thread,
+            // so it's probably fine not to wrap it.rmt
+            setDataSource(context, cover.songUri)
+
+            // Get the embedded picture from MediaMetadataRetriever, which will return a full
+            // ByteArray of the cover without any compression artifacts.
+            // If its null [i.e there is no embedded cover], than just ignore it and move on
+            embeddedPicture?.let { ByteArrayInputStream(it) }.also { release() }
+        }
+
+    private suspend fun extractExoplayerCover(cover: Cover.Embedded): InputStream? {
+        val tracks =
+            MetadataRetriever.retrieveMetadata(mediaSourceFactory, MediaItem.fromUri(cover.songUri))
+                .asDeferred()
+                .await()
+
+        // The metadata extraction process of ExoPlayer results in a dump of all metadata
+        // it found, which must be iterated through.
+        val metadata = tracks[0].getFormat(0).metadata
+
+        if (metadata == null || metadata.length() == 0) {
+            // No (parsable) metadata. This is also expected.
+            return null
+        }
+
+        return findCoverDataInMetadata(metadata)
+    }
+
+    @SuppressLint("Recycle")
+    private suspend fun extractMediaStoreCover(cover: Cover) =
+        // Eliminate any chance that this blocking call might mess up the loading process
+        withContext(Dispatchers.IO) {
+            // Coil will recycle this InputStream, so we don't need to worry about it.
+            context.contentResolver.openInputStream(cover.mediaStoreCoverUri)
+        }
+
+    /** Derived from phonograph: https://github.com/kabouzeid/Phonograph */
+    private suspend fun createMosaic(streams: List<InputStream>, size: Size): FetchResult {
+        // Use whatever size coil gives us to create the mosaic.
+        val mosaicSize = AndroidSize(size.width.mosaicSize(), size.height.mosaicSize())
+        val mosaicFrameSize =
+            Size(Dimension(mosaicSize.width / 2), Dimension(mosaicSize.height / 2))
+
+        val mosaicBitmap =
+            Bitmap.createBitmap(mosaicSize.width, mosaicSize.height, Bitmap.Config.ARGB_8888)
+        val canvas = Canvas(mosaicBitmap)
+
+        var x = 0
+        var y = 0
+
+        // For each stream, create a bitmap scaled to 1/4th of the mosaics combined size
+        // and place it on a corner of the canvas.
+        for (stream in streams) {
+            if (y == mosaicSize.height) {
+                break
+            }
+
+            // Crop the bitmap down to a square so it leaves no empty space
+            // TODO: Work around this
+            val bitmap =
+                SquareCropTransformation.INSTANCE.transform(
+                    BitmapFactory.decodeStream(stream), mosaicFrameSize)
+            canvas.drawBitmap(bitmap, x.toFloat(), y.toFloat(), null)
+
+            x += bitmap.width
+            if (x == mosaicSize.width) {
+                x = 0
+                y += bitmap.height
+            }
+        }
+
+        // It's way easier to map this into a drawable then try to serialize it into an
+        // BufferedSource. Just make sure we mark it as "sampled" so Coil doesn't try to
+        // load low-res mosaics into high-res ImageViews.
+        return DrawableResult(
+            drawable = mosaicBitmap.toDrawable(context.resources),
+            isSampled = true,
+            dataSource = DataSource.DISK)
+    }
+
+    private fun Dimension.mosaicSize(): Int {
+        // Since we want the mosaic to be perfectly divisible into two, we need to round any
+        // odd image sizes upwards to prevent the mosaic creation from failing.
+        val size = pxOrElse { 512 }
+        return if (size.mod(2) > 0) size + 1 else size
+    }
+}
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/DHash.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/DHash.kt
@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2024 Auxio Project
+ * DHash.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.image.extractor
+
+import android.graphics.Bitmap
+import android.graphics.Canvas
+import android.graphics.Color
+import android.graphics.ColorMatrix
+import android.graphics.ColorMatrixColorFilter
+import android.graphics.Paint
+import java.math.BigInteger
+
+@Suppress("UNUSED")
+fun Bitmap.dHash(hashSize: Int = 16): String {
+    // Step 1: Resize the bitmap to a fixed size
+    val resizedBitmap = Bitmap.createScaledBitmap(this, hashSize + 1, hashSize, true)
+
+    // Step 2: Convert the bitmap to grayscale
+    val grayBitmap =
+        Bitmap.createBitmap(resizedBitmap.width, resizedBitmap.height, Bitmap.Config.ARGB_8888)
+    val canvas = Canvas(grayBitmap)
+    val paint = Paint()
+    val colorMatrix = ColorMatrix()
+    colorMatrix.setSaturation(0f)
+    val filter = ColorMatrixColorFilter(colorMatrix)
+    paint.colorFilter = filter
+    canvas.drawBitmap(resizedBitmap, 0f, 0f, paint)
+
+    // Step 3: Compute the difference between adjacent pixels
+    var hash = BigInteger.valueOf(0)
+    val one = BigInteger.valueOf(1)
+    for (y in 0 until hashSize) {
+        for (x in 0 until hashSize) {
+            val pixel1 = grayBitmap.getPixel(x, y)
+            val pixel2 = grayBitmap.getPixel(x + 1, y)
+            val diff = Color.red(pixel1) - Color.red(pixel2)
+            if (diff > 0) {
+                hash = hash.or(one.shl(y * hashSize + x))
+            }
+        }
+    }
+
+    return hash.toString(16)
+}
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/ErrorCrossfadeTransitionFactory.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/ErrorCrossfadeTransitionFactory.kt
@ -16,15 +16,15 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.auxio.image.coil
+package org.oxycblt.auxio.image.extractor

-import coil3.decode.DataSource
-import coil3.request.ImageResult
-import coil3.request.SuccessResult
-import coil3.transition.CrossfadeDrawable
-import coil3.transition.CrossfadeTransition
-import coil3.transition.Transition
-import coil3.transition.TransitionTarget
+import coil.decode.DataSource
+import coil.drawable.CrossfadeDrawable
+import coil.request.ImageResult
+import coil.request.SuccessResult
+import coil.transition.CrossfadeTransition
+import coil.transition.Transition
+import coil.transition.TransitionTarget

 /**
 * A copy of [CrossfadeTransition.Factory] that also applies a transition to error results.
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/ExtractorModule.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/ExtractorModule.kt
@ -1,6 +1,6 @@
 /*
 * Copyright (c) 2023 Auxio Project
- * CoilModule.kt is part of Auxio.
+ * ExtractorModule.kt is part of Auxio.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
@ -16,12 +16,11 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.auxio.image.coil
+package org.oxycblt.auxio.image.extractor

 import android.content.Context
-import coil3.ImageLoader
-import coil3.request.CachePolicy
-import coil3.request.transitionFactory
+import coil.ImageLoader
+import coil.request.CachePolicy
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
@ -31,22 +30,19 @@ import javax.inject.Singleton

@Module
@InstallIn(SingletonComponent::class)
-class CoilModule {
+class ExtractorModule {
    @Singleton
    @Provides
    fun imageLoader(
        @ApplicationContext context: Context,
-        coverKeyer: CoverKeyer,
-        coverFactory: CoverFetcher.Factory,
-        coverCollectionKeyer: CoverCollectionKeyer,
-        coverCollectionFactory: CoverCollectionFetcher.Factory
+        keyer: CoverKeyer,
+        factory: CoverFetcher.Factory
    ) =
        ImageLoader.Builder(context)
            .components {
-                add(coverKeyer)
-                add(coverFactory)
-                add(coverCollectionKeyer)
-                add(coverCollectionFactory)
+                // Add fetchers for Music components to make them usable with ImageRequest
+                add(keyer)
+                add(factory)
            }
            // Use our own crossfade with error drawable support
            .transitionFactory(ErrorCrossfadeTransitionFactory())
--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/RoundedRectTransformation.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/RoundedRectTransformation.kt
@ -16,7 +16,7 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.auxio.image.coil
+package org.oxycblt.auxio.image.extractor

 import android.graphics.Bitmap
 import android.graphics.Bitmap.createBitmap
@ -30,16 +30,16 @@ import android.graphics.RectF
 import android.graphics.Shader
 import androidx.annotation.Px
 import androidx.core.graphics.applyCanvas
-import coil3.decode.DecodeUtils
-import coil3.size.Scale
-import coil3.size.Size
-import coil3.size.pxOrElse
-import coil3.transform.Transformation
+import coil.decode.DecodeUtils
+import coil.size.Scale
+import coil.size.Size
+import coil.size.pxOrElse
+import coil.transform.Transformation
 import kotlin.math.roundToInt

 /**
- * A vendoring of coil's RoundedCornersTransformation that can handle non-1:1 aspect ratio images
- * without cropping them.
+ * A vendoring of [coil.transform.RoundedCornersTransformation] that can handle non-1:1 aspect ratio
+ * images without cropping them.
 *
 * @author Coil Team, Alexander Capehart (OxygenCobalt)
 */
@ -48,7 +48,7 @@ class RoundedRectTransformation(
    @Px private val topRight: Float = 0f,
    @Px private val bottomLeft: Float = 0f,
    @Px private val bottomRight: Float = 0f
-) : Transformation() {
+) : Transformation {

    constructor(@Px radius: Float) : this(radius, radius, radius, radius)

--- a/app/src/main/java/org/oxycblt/auxio/image/extractor/SquareCropTransformation.kt
+++ b/app/src/main/java/org/oxycblt/auxio/image/extractor/SquareCropTransformation.kt
@ -16,13 +16,12 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.auxio.image.coil
+package org.oxycblt.auxio.image.extractor

 import android.graphics.Bitmap
-import androidx.core.graphics.scale
-import coil3.size.Size
-import coil3.size.pxOrElse
-import coil3.transform.Transformation
+import coil.size.Size
+import coil.size.pxOrElse
+import coil.transform.Transformation
 import kotlin.math.min

 /**
@ -31,7 +30,7 @@ import kotlin.math.min
 *
 * @author Alexander Capehart (OxygenCobalt)
 */
-class SquareCropTransformation : Transformation() {
+class SquareCropTransformation : Transformation {
    override val cacheKey: String
        get() = "SquareCropTransformation"

@ -47,7 +46,7 @@ class SquareCropTransformation : Transformation() {
        val desiredHeight = size.height.pxOrElse { dstSize }
        if (dstSize != desiredWidth || dstSize != desiredHeight) {
            // Image is not the desired size, upscale it.
-            return dst.scale(desiredWidth, desiredHeight)
+            return Bitmap.createScaledBitmap(dst, desiredWidth, desiredHeight, true)
        }
        return dst
    }
--- a/app/src/main/java/org/oxycblt/auxio/list/Data.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/Data.kt
@ -22,9 +22,9 @@ import androidx.annotation.StringRes

 // TODO: Consider breaking this up into sealed classes for individual adapters
 /** A marker for something that is a RecyclerView item. Has no functionality on it's own. */
-typealias Item = Any
+interface Item

-interface Header
+interface Header : Item

 /**
 * A "header" used for delimiting groups of data.
@ -44,7 +44,7 @@ interface PlainHeader : Header {
 */
 data class BasicHeader(@StringRes override val titleRes: Int) : PlainHeader

-interface Divider<T> {
+interface Divider<T> : Item {
    val anchor: T?
 }

--- a/app/src/main/java/org/oxycblt/auxio/list/ListFragment.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/ListFragment.kt
@ -20,7 +20,7 @@ package org.oxycblt.auxio.list

 import androidx.recyclerview.widget.RecyclerView
 import androidx.viewbinding.ViewBinding
-import org.oxycblt.musikr.Music
+import org.oxycblt.auxio.music.Music

 /**
 * A Fragment containing a selectable list.
--- a/app/src/main/java/org/oxycblt/auxio/list/ListViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/ListViewModel.kt
@ -25,17 +25,17 @@ import javax.inject.Inject
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import org.oxycblt.auxio.list.menu.Menu
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicRepository
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaySong
 import org.oxycblt.auxio.util.Event
 import org.oxycblt.auxio.util.MutableEvent
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.MusicParent
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
@ -64,17 +64,18 @@ constructor(private val listSettings: ListSettings, private val musicRepository:
    }

    override fun onMusicChanges(changes: MusicRepository.Changes) {
-        val library = musicRepository.library ?: return
+        val deviceLibrary = musicRepository.deviceLibrary ?: return
+        val userLibrary = musicRepository.userLibrary ?: return
        // Sanitize the selection to remove items that no longer exist and thus
        // won't appear in any list.
        _selected.value =
            _selected.value.mapNotNull {
                when (it) {
-                    is Song -> library.findSong(it.uid)
-                    is Album -> library.findAlbum(it.uid)
-                    is Artist -> library.findArtist(it.uid)
-                    is Genre -> library.findGenre(it.uid)
-                    is Playlist -> library.findPlaylist(it.uid)
+                    is Song -> deviceLibrary.findSong(it.uid)
+                    is Album -> deviceLibrary.findAlbum(it.uid)
+                    is Artist -> deviceLibrary.findArtist(it.uid)
+                    is Genre -> deviceLibrary.findGenre(it.uid)
+                    is Playlist -> userLibrary.findPlaylist(it.uid)
                }
            }
    }
--- a/app/src/main/java/org/oxycblt/auxio/list/adapter/SelectionIndicatorAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/adapter/SelectionIndicatorAdapter.kt
@ -21,7 +21,7 @@ package org.oxycblt.auxio.list.adapter
 import android.view.View
 import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.musikr.Music
+import org.oxycblt.auxio.music.Music
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/list/menu/Menu.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/menu/Menu.kt
@ -21,13 +21,13 @@ package org.oxycblt.auxio.list.menu
 import android.os.Parcelable
 import androidx.annotation.MenuRes
 import kotlinx.parcelize.Parcelize
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaySong
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song

 /**
 * Command to navigate to a specific menu dialog configuration.
--- a/app/src/main/java/org/oxycblt/auxio/list/menu/MenuDialogFragmentImpl.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/menu/MenuDialogFragmentImpl.kt
@ -27,18 +27,17 @@ import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.DialogMenuBinding
 import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.list.ListViewModel
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
 import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.resolveNames
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.formatDurationMs
 import org.oxycblt.auxio.util.getPlural
 import org.oxycblt.auxio.util.share
 import org.oxycblt.auxio.util.showToast
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song

 /**
 * [MenuDialogFragment] implementation for a [Song].
@ -113,7 +112,7 @@ class AlbumMenuDialogFragment : MenuDialogFragment<Menu.ForAlbum>() {
    override fun updateMenu(binding: DialogMenuBinding, menu: Menu.ForAlbum) {
        val context = requireContext()
        binding.menuCover.bind(menu.album)
-        binding.menuType.text = menu.album.releaseType.resolve(context)
+        binding.menuType.text = getString(menu.album.releaseType.stringRes)
        binding.menuName.text = menu.album.name.resolve(context)
        binding.menuInfo.text = menu.album.artists.resolveNames(context)
    }
--- a/app/src/main/java/org/oxycblt/auxio/list/menu/MenuViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/menu/MenuViewModel.kt
@ -23,9 +23,9 @@ import dagger.hilt.android.lifecycle.HiltViewModel
 import javax.inject.Inject
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
+import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.MusicRepository
 import org.oxycblt.auxio.playback.PlaySong
-import org.oxycblt.musikr.MusicParent
 import timber.log.Timber as L

 /**
@ -70,35 +70,35 @@ class MenuViewModel @Inject constructor(private val musicRepository: MusicReposi
        }

    private fun unpackSongParcel(parcel: Menu.ForSong.Parcel): Menu.ForSong? {
-        val song = musicRepository.library?.findSong(parcel.songUid) ?: return null
+        val song = musicRepository.deviceLibrary?.findSong(parcel.songUid) ?: return null
        val parent = parcel.playWithUid?.let(musicRepository::find) as MusicParent?
        val playWith = PlaySong.fromIntCode(parcel.playWithCode, parent) ?: return null
        return Menu.ForSong(parcel.res, song, playWith)
    }

    private fun unpackAlbumParcel(parcel: Menu.ForAlbum.Parcel): Menu.ForAlbum? {
-        val album = musicRepository.library?.findAlbum(parcel.albumUid) ?: return null
+        val album = musicRepository.deviceLibrary?.findAlbum(parcel.albumUid) ?: return null
        return Menu.ForAlbum(parcel.res, album)
    }

    private fun unpackArtistParcel(parcel: Menu.ForArtist.Parcel): Menu.ForArtist? {
-        val artist = musicRepository.library?.findArtist(parcel.artistUid) ?: return null
+        val artist = musicRepository.deviceLibrary?.findArtist(parcel.artistUid) ?: return null
        return Menu.ForArtist(parcel.res, artist)
    }

    private fun unpackGenreParcel(parcel: Menu.ForGenre.Parcel): Menu.ForGenre? {
-        val genre = musicRepository.library?.findGenre(parcel.genreUid) ?: return null
+        val genre = musicRepository.deviceLibrary?.findGenre(parcel.genreUid) ?: return null
        return Menu.ForGenre(parcel.res, genre)
    }

    private fun unpackPlaylistParcel(parcel: Menu.ForPlaylist.Parcel): Menu.ForPlaylist? {
-        val playlist = musicRepository.library?.findPlaylist(parcel.playlistUid) ?: return null
+        val playlist = musicRepository.userLibrary?.findPlaylist(parcel.playlistUid) ?: return null
        return Menu.ForPlaylist(parcel.res, playlist)
    }

    private fun unpackSelectionParcel(parcel: Menu.ForSelection.Parcel): Menu.ForSelection? {
-        val library = musicRepository.library ?: return null
-        val songs = parcel.songUids.mapNotNull(library::findSong)
+        val deviceLibrary = musicRepository.deviceLibrary ?: return null
+        val songs = parcel.songUids.mapNotNull(deviceLibrary::findSong)
        return Menu.ForSelection(parcel.res, songs)
    }
 }
--- a/app/src/main/java/org/oxycblt/auxio/list/recycler/FastScrollRecyclerView.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/recycler/FastScrollRecyclerView.kt
@ -19,37 +19,21 @@
 package org.oxycblt.auxio.list.recycler

 import android.animation.Animator
-import android.annotation.SuppressLint
 import android.content.Context
 import android.graphics.Canvas
 import android.graphics.Rect
-import android.os.Build
-import android.text.TextUtils
 import android.util.AttributeSet
-import android.view.Gravity
-import android.view.HapticFeedbackConstants
 import android.view.MotionEvent
-import android.view.View
 import android.view.ViewConfiguration
-import android.view.ViewGroup
 import android.view.WindowInsets
-import android.widget.FrameLayout
 import androidx.annotation.AttrRes
-import androidx.core.view.isEmpty
-import androidx.core.view.isInvisible
-import androidx.core.view.updatePaddingRelative
-import androidx.core.widget.TextViewCompat
 import androidx.recyclerview.widget.RecyclerView
-import com.google.android.material.textview.MaterialTextView
 import kotlin.math.abs
 import kotlin.math.max
 import kotlin.math.roundToInt
 import org.oxycblt.auxio.R
-import org.oxycblt.auxio.ui.MaterialFadingSlider
 import org.oxycblt.auxio.ui.MaterialSlider
-import org.oxycblt.auxio.util.getAttrColorCompat
 import org.oxycblt.auxio.util.getDimenPixels
-import org.oxycblt.auxio.util.getDrawableCompat
 import org.oxycblt.auxio.util.inflater
 import org.oxycblt.auxio.util.isRtl
 import org.oxycblt.auxio.util.isUnder
@ -78,70 +62,33 @@ import org.oxycblt.auxio.util.systemBarInsetsCompat
 * - Added drag listener
 * - Added documentation
 * - Completely new design
- * - New scroll position backend
 *
 * @author Hai Zhang, Alexander Capehart (OxygenCobalt)
+ *
+ * TODO: Add vibration when popup changes
+ * TODO: Improve support for variably sized items (Re-back with library fast scroller?)
 */
 class FastScrollRecyclerView
@JvmOverloads
 constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr: Int = 0) :
    AuxioRecyclerView(context, attrs, defStyleAttr) {
    // Thumb
-    private val thumbWidth = context.getDimenPixels(R.dimen.spacing_mid_medium)
-    private val thumbHeight = context.getDimenPixels(R.dimen.size_touchable_medium)
-    private val thumbSlider = MaterialSlider.small(context, thumbWidth)
+    private val thumbSize = context.getDimenPixels(R.dimen.size_touchable_small)
+    private val slider = MaterialSlider(context, thumbSize)
    private var thumbAnimator: Animator? = null

-    @SuppressLint("InflateParams")
    private val thumbView =
-        context.inflater.inflate(R.layout.view_scroll_thumb, null).apply {
-            thumbSlider.jumpOut(this)
-        }
+        context.inflater.inflate(R.layout.view_scroll_thumb, null).apply { slider.jumpOut(this) }
    private val thumbPadding = Rect(0, 0, 0, 0)
    private var thumbOffset = 0

    private var showingThumb = false
    private val hideThumbRunnable = Runnable {
        if (!dragging) {
-            hideThumb()
+            hideScrollbar()
        }
    }

-    private val popupView =
-        MaterialTextView(context).apply {
-            minimumWidth = context.getDimenPixels(R.dimen.size_touchable_large)
-            minimumHeight = context.getDimenPixels(R.dimen.size_touchable_small)
-
-            TextViewCompat.setTextAppearance(this, R.style.TextAppearance_Auxio_HeadlineMedium)
-            setTextColor(
-                context.getAttrColorCompat(com.google.android.material.R.attr.colorOnSecondary))
-            ellipsize = TextUtils.TruncateAt.MIDDLE
-            gravity = Gravity.CENTER
-            includeFontPadding = false
-
-            elevation =
-                context
-                    .getDimenPixels(com.google.android.material.R.dimen.m3_sys_elevation_level1)
-                    .toFloat()
-            background = context.getDrawableCompat(R.drawable.ui_popup)
-            val paddingStart = context.getDimenPixels(R.dimen.spacing_medium)
-            val paddingEnd = paddingStart + context.getDimenPixels(R.dimen.spacing_tiny) / 2
-            updatePaddingRelative(start = paddingStart, end = paddingEnd)
-            layoutParams =
-                FrameLayout.LayoutParams(
-                        ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)
-                    .apply {
-                        marginEnd = context.getDimenPixels(R.dimen.size_touchable_small)
-                        gravity = Gravity.CENTER_HORIZONTAL or Gravity.TOP
-                    }
-        }
-    private val popupSlider =
-        MaterialFadingSlider(MaterialSlider.large(context, popupView.minimumWidth / 2)).apply {
-            jumpOut(popupView)
-        }
-    private var popupAnimator: Animator? = null
-    private var showingPopup = false
-
    // Touch
    private val minTouchTargetSize = context.getDimenPixels(R.dimen.size_touchable_small)
    private val touchSlop = ViewConfiguration.get(context).scaledTouchSlop
@ -152,24 +99,6 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
    private var dragStartY = 0f
    private var dragStartThumbOffset = 0

-    private var fastScrollingPossible = true
-
-    var fastScrollingEnabled = true
-        set(value) {
-            if (field == value) {
-                return
-            }
-
-            field = value
-            if (!value) {
-                removeCallbacks(hideThumbRunnable)
-                hideThumb()
-                hidePopup()
-            }
-
-            listener?.onFastScrollingChanged(field)
-        }
-
    private var dragging = false
        set(value) {
            if (field == value) {
@ -187,9 +116,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
            if (field) {
                removeCallbacks(hideThumbRunnable)
                showScrollbar()
-                showPopup()
            } else {
-                hidePopup()
                postAutoHideScrollbar()
            }

@ -201,7 +128,6 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr

    init {
        overlay.add(thumbView)
-        overlay.add(popupView)

        addItemDecoration(
            object : ItemDecoration() {
@ -230,96 +156,26 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
    // --- RECYCLERVIEW EVENT MANAGEMENT ---

    private fun onPreDraw() {
-        updateThumbState()
+        updateScrollbarState()

        thumbView.layoutDirection = layoutDirection
        thumbView.measure(
-            MeasureSpec.makeMeasureSpec(thumbWidth, MeasureSpec.EXACTLY),
-            MeasureSpec.makeMeasureSpec(thumbHeight, MeasureSpec.EXACTLY))
+            MeasureSpec.makeMeasureSpec(thumbSize, MeasureSpec.EXACTLY),
+            MeasureSpec.makeMeasureSpec(thumbSize, MeasureSpec.EXACTLY))
        val thumbTop = thumbPadding.top + thumbOffset
        val thumbLeft =
            if (isRtl) {
                thumbPadding.left
            } else {
-                width - thumbPadding.right - thumbWidth
+                width - thumbPadding.right - thumbSize
            }
-        thumbView.layout(thumbLeft, thumbTop, thumbLeft + thumbWidth, thumbTop + thumbHeight)
-
-        popupView.layoutDirection = layoutDirection
-        val child = getChildAt(0)
-        val firstAdapterPos =
-            if (child != null) {
-                layoutManager?.getPosition(child) ?: NO_POSITION
-            } else {
-                NO_POSITION
-            }
-
-        val popupText: String
-        val provider = popupProvider
-        if (firstAdapterPos != NO_POSITION && provider != null) {
-            popupView.isInvisible = false
-            // Get the popup text. If there is none, we default to "?".
-            popupText = provider.getPopup(firstAdapterPos) ?: "?"
-        } else {
-            // No valid position or provider, do not show the popup.
-            popupView.isInvisible = false
-            popupText = ""
-        }
-        val popupLayoutParams = popupView.layoutParams as FrameLayout.LayoutParams
-
-        if (popupView.text != popupText) {
-            popupView.text = popupText
-
-            val widthMeasureSpec =
-                ViewGroup.getChildMeasureSpec(
-                    MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY),
-                    thumbPadding.left +
-                        thumbPadding.right +
-                        thumbWidth +
-                        popupLayoutParams.leftMargin +
-                        popupLayoutParams.rightMargin,
-                    popupLayoutParams.width)
-
-            val heightMeasureSpec =
-                ViewGroup.getChildMeasureSpec(
-                    MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY),
-                    thumbPadding.top +
-                        thumbPadding.bottom +
-                        popupLayoutParams.topMargin +
-                        popupLayoutParams.bottomMargin,
-                    popupLayoutParams.height)
-
-            popupView.measure(widthMeasureSpec, heightMeasureSpec)
-            if (showingPopup) {
-                doPopupVibration()
-            }
-        }
-
-        val popupWidth = popupView.measuredWidth
-        val popupHeight = popupView.measuredHeight
-        val popupLeft =
-            if (layoutDirection == View.LAYOUT_DIRECTION_RTL) {
-                thumbPadding.left + thumbWidth + popupLayoutParams.leftMargin
-            } else {
-                width - thumbPadding.right - thumbWidth - popupLayoutParams.rightMargin - popupWidth
-            }
-
-        val popupAnchorY = popupHeight / 2
-        val thumbAnchorY = thumbView.height / 2
-
-        val popupTop =
-            (thumbTop + thumbAnchorY - popupAnchorY)
-                .coerceAtLeast(thumbPadding.top + popupLayoutParams.topMargin)
-                .coerceAtMost(
-                    height - thumbPadding.bottom - popupLayoutParams.bottomMargin - popupHeight)
-
-        popupView.layout(popupLeft, popupTop, popupLeft + popupWidth, popupTop + popupHeight)
+        thumbView.layout(thumbLeft, thumbTop, thumbLeft + thumbSize, thumbTop + thumbSize)
    }

    override fun onScrolled(dx: Int, dy: Int) {
        super.onScrolled(dx, dy)

-        updateThumbState()
+        updateScrollbarState()

        // Measure or layout events result in a fake onScrolled call. Ignore those.
        if (dx == 0 && dy == 0) {
@ -337,15 +193,11 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
        return insets
    }

-    private fun updateThumbState() {
+    private fun updateScrollbarState() {
        // Then calculate the thumb position, which is just:
        // [proportion of scroll position to scroll range] * [total thumb range]
-        // This is somewhat adapted from the androidx RecyclerView FastScroller implementation.
        val offsetY = computeVerticalScrollOffset()
-        if (computeVerticalScrollRange() < height || isEmpty()) {
-            fastScrollingPossible = false
-            hideThumb()
-            hidePopup()
+        if (computeVerticalScrollRange() < height || childCount == 0) {
            return
        }
        val extentY = computeVerticalScrollExtent()
@ -354,10 +206,6 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
    }

    private fun onItemTouch(event: MotionEvent): Boolean {
-        if (!fastScrollingEnabled || !fastScrollingPossible) {
-            dragging = false
-            return false
-        }
        val eventX = event.x
        val eventY = event.y

@ -371,9 +219,8 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr

                    if (thumbView.isUnder(eventX, eventY, minTouchTargetSize)) {
                        dragStartThumbOffset = thumbOffset
-                    } else if (eventX > thumbView.right - thumbWidth / 4) {
-                        dragStartThumbOffset =
-                            (eventY - thumbPadding.top - thumbHeight / 2f).toInt()
+                    } else if (eventX > thumbView.right - thumbSize / 4) {
+                        dragStartThumbOffset = (eventY - thumbPadding.top - thumbSize / 2f).toInt()
                        scrollToThumbOffset(dragStartThumbOffset)
                    } else {
                        return false
@ -391,8 +238,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
                        dragStartThumbOffset = thumbOffset
                    } else {
                        dragStartY = eventY
-                        dragStartThumbOffset =
-                            (eventY - thumbPadding.top - thumbHeight / 2f).toInt()
+                        dragStartThumbOffset = (eventY - thumbPadding.top - thumbSize / 2f).toInt()
                        scrollToThumbOffset(dragStartThumbOffset)
                    }

@ -436,65 +282,30 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
    }

    private fun showScrollbar() {
-        if (!fastScrollingEnabled || !fastScrollingPossible) {
-            return
-        }
        if (showingThumb) {
            return
        }

        showingThumb = true
        thumbAnimator?.cancel()
-        thumbAnimator = thumbSlider.slideIn(thumbView).also { it.start() }
+        thumbAnimator = slider.slideIn(thumbView).also { it.start() }
    }

-    private fun hideThumb() {
+    private fun hideScrollbar() {
        if (!showingThumb) {
            return
        }

        showingThumb = false
        thumbAnimator?.cancel()
-        thumbAnimator = thumbSlider.slideOut(thumbView).also { it.start() }
-    }
-
-    private fun showPopup() {
-        if (!fastScrollingEnabled || !fastScrollingPossible) {
-            return
-        }
-        if (showingPopup) {
-            return
-        }
-
-        showingPopup = true
-        popupAnimator?.cancel()
-        popupAnimator = popupSlider.slideIn(popupView).also { it.start() }
-    }
-
-    private fun hidePopup() {
-        if (!showingPopup) {
-            return
-        }
-
-        showingPopup = false
-        popupAnimator?.cancel()
-        popupAnimator = popupSlider.slideOut(popupView).also { it.start() }
-    }
-
-    private fun doPopupVibration() {
-        performHapticFeedback(
-            if (Build.VERSION.SDK_INT >= 27) {
-                HapticFeedbackConstants.TEXT_HANDLE_MOVE
-            } else {
-                HapticFeedbackConstants.KEYBOARD_TAP
-            })
+        thumbAnimator = slider.slideOut(thumbView).also { it.start() }
    }

    // --- LAYOUT STATE ---

    private val thumbOffsetRange: Int
        get() {
-            return height - thumbPadding.top - thumbPadding.bottom - thumbHeight
+            return height - thumbPadding.top - thumbPadding.bottom - thumbSize
        }

    /** An interface to provide text to use in the popup when fast-scrolling. */
--- a/app/src/main/java/org/oxycblt/auxio/list/recycler/MaterialDragCallback.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/recycler/MaterialDragCallback.kt
@ -92,6 +92,7 @@ abstract class MaterialDragCallback : ItemTouchHelper.Callback() {

        // Hook drag events to "lifting" the item (i.e raising it's elevation). Make sure
        // this is only done once when the item is initially picked up.
+        // TODO: I think this is possible to improve with a raw ValueAnimator.
        if (shouldLift && isCurrentlyActive && actionState == ItemTouchHelper.ACTION_STATE_DRAG) {
            L.d("Lifting ViewHolder")

--- a/app/src/main/java/org/oxycblt/auxio/list/recycler/ViewHolders.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/recycler/ViewHolders.kt
@ -32,17 +32,16 @@ import org.oxycblt.auxio.list.PlainDivider
 import org.oxycblt.auxio.list.SelectableListListener
 import org.oxycblt.auxio.list.adapter.SelectionIndicatorAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.areNamesTheSame
-import org.oxycblt.auxio.music.resolve
 import org.oxycblt.auxio.music.resolveNames
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.getPlural
 import org.oxycblt.auxio.util.inflater
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song

 /**
 * A [RecyclerView.ViewHolder] that displays a [Song]. Use [from] to create an instance.
--- a/app/src/main/java/org/oxycblt/auxio/list/sort/Sort.kt
+++ b/app/src/main/java/org/oxycblt/auxio/list/sort/Sort.kt
@ -20,11 +20,11 @@ package org.oxycblt.auxio.list.sort

 import org.oxycblt.auxio.IntegerTable
 import org.oxycblt.auxio.R
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.Song

 /**
 * A sorting method.
@ -360,16 +360,16 @@ data class Sort(val mode: Mode, val direction: Direction) {
            override fun sortSongs(songs: MutableList<Song>, direction: Direction) {
                songs.sortBy { it.name }
                when (direction) {
-                    Direction.ASCENDING -> songs.sortBy { it.addedMs }
-                    Direction.DESCENDING -> songs.sortByDescending { it.addedMs }
+                    Direction.ASCENDING -> songs.sortBy { it.dateAdded }
+                    Direction.DESCENDING -> songs.sortByDescending { it.dateAdded }
                }
            }

            override fun sortAlbums(albums: MutableList<Album>, direction: Direction) {
                albums.sortBy { it.name }
                when (direction) {
-                    Direction.ASCENDING -> albums.sortBy { it.addedMs }
-                    Direction.DESCENDING -> albums.sortByDescending { it.addedMs }
+                    Direction.ASCENDING -> albums.sortBy { it.dateAdded }
+                    Direction.DESCENDING -> albums.sortByDescending { it.dateAdded }
                }
            }
        }
--- a/app/src/main/java/org/oxycblt/auxio/music/Indexing.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/Indexing.kt
@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * Indexing.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.music
+
+import android.os.Build
+
+/** Version-aware permission identifier for reading audio files. */
+val PERMISSION_READ_AUDIO =
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+        android.Manifest.permission.READ_MEDIA_AUDIO
+    } else {
+        android.Manifest.permission.READ_EXTERNAL_STORAGE
+    }
+
+/**
+ * Represents the current state of the music loader.
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+sealed interface IndexingState {
+    /**
+     * Music loading is on-going.
+     *
+     * @param progress The current progress of the music loading.
+     */
+    data class Indexing(val progress: IndexingProgress) : IndexingState
+
+    /**
+     * Music loading has completed.
+     *
+     * @param error If music loading has failed, the error that occurred will be here. Otherwise, it
+     *   will be null.
+     */
+    data class Completed(val error: Exception?) : IndexingState
+}
+
+/**
+ * Represents the current progress of music loading.
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+sealed interface IndexingProgress {
+    /** Other work is being done that does not have a defined progress. */
+    data object Indeterminate : IndexingProgress
+
+    /**
+     * Songs are currently being loaded.
+     *
+     * @param current The current amount of songs loaded.
+     * @param total The projected total amount of songs.
+     */
+    data class Songs(val current: Int, val total: Int) : IndexingProgress
+}
+
+/**
+ * Thrown by the music loader when [PERMISSION_READ_AUDIO] was not granted.
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class NoAudioPermissionException : Exception() {
+    override val message = "Storage permissions are required to load music"
+}
+
+/**
+ * Thrown when no music was found.
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class NoMusicException : Exception() {
+    override val message = "No music was found on the device"
+}
--- a/app/src/main/java/org/oxycblt/auxio/music/Music.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/Music.kt
@ -16,25 +16,29 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.musikr
+package org.oxycblt.auxio.music

+import android.content.Context
 import android.net.Uri
 import android.os.Parcelable
 import androidx.room.TypeConverter
 import java.security.MessageDigest
 import java.util.UUID
+import kotlin.math.max
 import kotlinx.parcelize.IgnoredOnParcel
 import kotlinx.parcelize.Parcelize
-import org.oxycblt.musikr.covers.Cover
-import org.oxycblt.musikr.covers.CoverCollection
-import org.oxycblt.musikr.fs.Format
-import org.oxycblt.musikr.fs.Path
-import org.oxycblt.musikr.tag.Date
-import org.oxycblt.musikr.tag.Disc
-import org.oxycblt.musikr.tag.Name
-import org.oxycblt.musikr.tag.ReleaseType
-import org.oxycblt.musikr.tag.ReplayGainAdjustment
-import org.oxycblt.musikr.util.toUuidOrNull
+import org.oxycblt.auxio.image.extractor.Cover
+import org.oxycblt.auxio.image.extractor.ParentCover
+import org.oxycblt.auxio.list.Item
+import org.oxycblt.auxio.music.fs.MimeType
+import org.oxycblt.auxio.music.fs.Path
+import org.oxycblt.auxio.music.info.Date
+import org.oxycblt.auxio.music.info.Disc
+import org.oxycblt.auxio.music.info.Name
+import org.oxycblt.auxio.music.info.ReleaseType
+import org.oxycblt.auxio.playback.replaygain.ReplayGainAdjustment
+import org.oxycblt.auxio.util.concatLocalized
+import org.oxycblt.auxio.util.toUuidOrNull

 /**
 * Abstract music data. This contains universal information about all concrete music
@ -42,7 +46,7 @@ import org.oxycblt.musikr.util.toUuidOrNull
 *
 * @author Alexander Capehart (OxygenCobalt)
 */
-sealed interface Music {
+sealed interface Music : Item {
    /**
     * A unique identifier for this music item.
     *
@ -77,34 +81,23 @@ sealed interface Music {
    class UID
    private constructor(
        private val format: Format,
-        private val item: Item,
+        private val type: MusicType,
        private val uuid: UUID
    ) : Parcelable {
        // Cache the hashCode for HashMap efficiency.
        @IgnoredOnParcel private var hashCode = format.hashCode()

        init {
-            hashCode = 31 * hashCode + item.hashCode()
+            hashCode = 31 * hashCode + type.hashCode()
            hashCode = 31 * hashCode + uuid.hashCode()
        }

        override fun hashCode() = hashCode

        override fun equals(other: Any?) =
-            other is UID && format == other.format && item == other.item && uuid == other.uuid
+            other is UID && format == other.format && type == other.type && uuid == other.uuid

-        override fun toString() = "${format.namespace}:${item.intCode.toString(16)}-$uuid"
-
-        internal enum class Item(val intCode: Int) {
-            // Item used to be MusicType back when the music module was
-            // part of Auxio, so these old integer codes remain.
-            // TODO: Introduce new UID format that removes these.
-            SONG(0xA10B),
-            ALBUM(0xA10A),
-            ARTIST(0xA109),
-            GENRE(0xA108),
-            PLAYLIST(0xA107)
-        }
+        override fun toString() = "${format.namespace}:${type.intCode.toString(16)}-$uuid"

        /**
         * Internal marker of [Music.UID] format type.
@ -124,7 +117,7 @@ sealed interface Music {
            @TypeConverter fun fromMusicUID(uid: UID?) = uid?.toString()

            /** @see [Music.UID.fromString] */
-            @TypeConverter fun toMusicUid(string: String?) = string?.let(Companion::fromString)
+            @TypeConverter fun toMusicUid(string: String?) = string?.let(UID::fromString)
        }

        companion object {
@ -132,23 +125,23 @@ sealed interface Music {
             * Creates an Auxio-style [UID] of random composition. Used if there is no
             * non-subjective, unlikely-to-change metadata of the music.
             *
-             * @param item The type of [Item] that created this [UID].
+             * @param type The analogous [MusicType] of the item that created this [UID].
             */
-            internal fun auxio(item: Item): UID {
-                return UID(Format.AUXIO, item, UUID.randomUUID())
+            fun auxio(type: MusicType): UID {
+                return UID(Format.AUXIO, type, UUID.randomUUID())
            }

            /**
             * Creates an Auxio-style [UID] with a [UUID] composed of a hash of the non-subjective,
             * unlikely-to-change metadata of the music.
             *
-             * @param item The type of [Item] that created this [UID].
+             * @param type The analogous [MusicType] of the item that created this [UID].
             * @param updates Block to update the [MessageDigest] hash with the metadata of the
             *   item. Make sure the metadata hashed semantically aligns with the format
             *   specification.
             * @return A new auxio-style [UID].
             */
-            internal fun auxio(item: Item, updates: MessageDigest.() -> Unit): UID {
+            fun auxio(type: MusicType, updates: MessageDigest.() -> Unit): UID {
                val digest =
                    MessageDigest.getInstance("SHA-256").run {
                        updates()
@ -178,19 +171,19 @@ sealed interface Music {
                            .or(digest[13].toLong().and(0xFF).shl(16))
                            .or(digest[14].toLong().and(0xFF).shl(8))
                            .or(digest[15].toLong().and(0xFF)))
-                return UID(Format.AUXIO, item, uuid)
+                return UID(Format.AUXIO, type, uuid)
            }

            /**
             * Creates a MusicBrainz-style [UID] with a [UUID] derived from the MusicBrainz ID
             * extracted from a file.
             *
-             * @param item The [Item] that created this [UID].
+             * @param type The analogous [MusicType] of the item that created this [UID].
             * @param mbid The analogous MusicBrainz ID for this item that was extracted from a
             *   file.
             * @return A new MusicBrainz-style [UID].
             */
-            internal fun musicBrainz(item: Item, mbid: UUID) = UID(Format.MUSICBRAINZ, item, mbid)
+            fun musicBrainz(type: MusicType, mbid: UUID) = UID(Format.MUSICBRAINZ, type, mbid)

            /**
             * Convert a [UID]'s string representation back into a concrete [UID] instance.
@ -218,8 +211,8 @@ sealed interface Music {
                    return null
                }

-                val intCode = ids[0].toIntOrNull(16) ?: return null
-                val type = Item.entries.firstOrNull { it.intCode == intCode } ?: return null
+                val type =
+                    MusicType.fromIntCode(ids[0].toIntOrNull(16) ?: return null) ?: return null
                val uuid = ids[1].toUuidOrNull() ?: return null
                return UID(format, type, uuid)
            }
@ -243,7 +236,6 @@ sealed interface MusicParent : Music {
 * @author Alexander Capehart (OxygenCobalt)
 */
 interface Song : Music {
-    override val name: Name.Known
    /** The track number. Will be null if no valid track number was present in the metadata. */
    val track: Int?
    /** The [Disc] number. Will be null if no valid disc number was present in the metadata. */
@ -255,32 +247,23 @@ interface Song : Music {
     * audio file in a way that is scoped-storage-safe.
     */
    val uri: Uri
+    /** Useful information to quickly obtain the album cover. */
+    val cover: Cover
    /**
     * The [Path] to this audio file. This is only intended for display, [uri] should be favored
     * instead for accessing the audio file.
     */
    val path: Path
-    /** The [Format] of the audio file. Only intended for display. */
-    val format: Format
+    /** The [MimeType] of the audio file. Only intended for display. */
+    val mimeType: MimeType
    /** The size of the audio file, in bytes. */
    val size: Long
    /** The duration of the audio file, in milliseconds. */
    val durationMs: Long
-    /** The bitrate of the audio file, in kbps. */
-    val bitrateKbps: Int
-    /** The sample rate of the audio file, in Hz. */
-    val sampleRateHz: Int
    /** The ReplayGain adjustment to apply during playback. */
    val replayGainAdjustment: ReplayGainAdjustment
-    /**
-     * The date last modified the audio file was last modified, in milliseconds since the unix
-     * epoch.
-     */
-    val modifiedMs: Long
-    /** The time the audio file was added to the device, in milliseconds since the unix epoch. */
-    val addedMs: Long
-    /** Useful information to quickly obtain the album cover. */
-    val cover: Cover?
+    /** The date the audio file was added to the device, as a unix epoch timestamp. */
+    val dateAdded: Long
    /**
     * The parent [Album]. If the metadata did not specify an album, it's parent directory is used
     * instead.
@ -313,12 +296,12 @@ interface Album : MusicParent {
     * [ReleaseType.Album].
     */
    val releaseType: ReleaseType
-    /** Cover information from album's songs. */
-    val covers: CoverCollection
+    /** Cover information from the template song used for the album. */
+    val cover: ParentCover
    /** The duration of all songs in the album, in milliseconds. */
    val durationMs: Long
-    /** The earliest date a song in this album was added, in milliseconds since the unix epoch. */
-    val addedMs: Long
+    /** The earliest date a song in this album was added, as a unix epoch timestamp. */
+    val dateAdded: Long
    /**
     * The parent [Artist]s of this [Album]. Is often one, but there can be multiple if more than
     * one [Artist] name was specified in the metadata of the [Song]'s. Unlike [Song], album artists
@ -344,7 +327,7 @@ interface Artist : MusicParent {
     */
    val durationMs: Long?
    /** Useful information to quickly obtain a (single) cover for a Genre. */
-    val covers: CoverCollection
+    val cover: ParentCover
    /** The [Genre]s of this artist. */
    val genres: List<Genre>
 }
@ -360,7 +343,7 @@ interface Genre : MusicParent {
    /** The total duration of the songs in this genre, in milliseconds. */
    val durationMs: Long
    /** Useful information to quickly obtain a (single) cover for a Genre. */
-    val covers: CoverCollection
+    val cover: ParentCover
 }

 /**
@ -374,5 +357,34 @@ interface Playlist : MusicParent {
    /** The total duration of the songs in this genre, in milliseconds. */
    val durationMs: Long
    /** Useful information to quickly obtain a (single) cover for a Genre. */
-    val covers: CoverCollection
+    val cover: ParentCover?
+}
+
+/**
+ * Run [Name.resolve] on each instance in the given list and concatenate them into a [String] in a
+ * localized manner.
+ *
+ * @param context [Context] required
+ * @return A concatenated string.
+ */
+fun <T : Music> List<T>.resolveNames(context: Context) =
+    concatLocalized(context) { it.name.resolve(context) }
+
+/**
+ * Returns if [Music.name] matches for each item in a list. Useful for scenarios where the display
+ * information of an item must be compared without a context.
+ *
+ * @param other The list of items to compare to.
+ * @return True if they are the same (by [Music.name]), false otherwise.
+ */
+fun <T : Music> List<T>.areNamesTheSame(other: List<T>): Boolean {
+    for (i in 0 until max(size, other.size)) {
+        val a = getOrNull(i) ?: return false
+        val b = other.getOrNull(i) ?: return false
+        if (a.name != b.name) {
+            return false
+        }
+    }
+
+    return true
 }
--- a/app/src/main/java/org/oxycblt/auxio/music/MusicRepository.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/MusicRepository.kt
@ -19,30 +19,31 @@
 package org.oxycblt.auxio.music

 import android.content.Context
-import dagger.hilt.android.qualifiers.ApplicationContext
-import java.util.UUID
+import android.content.pm.PackageManager
+import androidx.core.content.ContextCompat
+import java.util.LinkedList
 import javax.inject.Inject
 import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
+import kotlinx.coroutines.async
+import kotlinx.coroutines.channels.Channel
+import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
+import kotlinx.coroutines.withTimeout
 import kotlinx.coroutines.yield
-import org.oxycblt.auxio.image.covers.SettingCovers
-import org.oxycblt.auxio.music.MusicRepository.IndexingWorker
-import org.oxycblt.auxio.music.shim.WriteOnlyMutableCache
-import org.oxycblt.musikr.IndexingProgress
-import org.oxycblt.musikr.Interpretation
-import org.oxycblt.musikr.Library
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Musikr
-import org.oxycblt.musikr.MutableLibrary
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.Storage
-import org.oxycblt.musikr.cache.MutableCache
-import org.oxycblt.musikr.playlist.db.StoredPlaylists
-import org.oxycblt.musikr.tag.interpret.Naming
-import org.oxycblt.musikr.tag.interpret.Separators
+import org.oxycblt.auxio.music.cache.CacheRepository
+import org.oxycblt.auxio.music.device.DeviceLibrary
+import org.oxycblt.auxio.music.device.RawSong
+import org.oxycblt.auxio.music.fs.MediaStoreExtractor
+import org.oxycblt.auxio.music.info.Name
+import org.oxycblt.auxio.music.metadata.Separators
+import org.oxycblt.auxio.music.metadata.TagExtractor
+import org.oxycblt.auxio.music.user.MutableUserLibrary
+import org.oxycblt.auxio.music.user.UserLibrary
+import org.oxycblt.auxio.util.DEFAULT_TIMEOUT
+import org.oxycblt.auxio.util.forEachWithTimeout
 import timber.log.Timber as L

 /**
@ -57,9 +58,10 @@ import timber.log.Timber as L
 *   configurations
 */
 interface MusicRepository {
-    /** The current library */
-    val library: Library?
-
+    /** The current music information found on the device. */
+    val deviceLibrary: DeviceLibrary?
+    /** The current user-defined music information. */
+    val userLibrary: UserLibrary?
    /** The current state of music loading. Null if no load has occurred yet. */
    val indexingState: IndexingState?

@ -173,7 +175,7 @@ interface MusicRepository {
     * @param withCache Whether to load with the music cache or not.
     * @return The top-level music loading [Job] started.
     */
-    suspend fun index(worker: IndexingWorker, withCache: Boolean)
+    fun index(worker: IndexingWorker, withCache: Boolean): Job

    /** A listener for changes to the stored music information. */
    interface UpdateListener {
@ -188,8 +190,8 @@ interface MusicRepository {
    /**
     * Flags indicating which kinds of music information changed.
     *
-     * @param deviceLibrary Whether the current songs/albums/artists/genres has changed.
-     * @param userLibrary Whether the current playlists have changed.
+     * @param deviceLibrary Whether the current [DeviceLibrary] has changed.
+     * @param userLibrary Whether the current [Playlist]s have changed.
     */
    data class Changes(val deviceLibrary: Boolean, val userLibrary: Boolean)

@ -201,6 +203,12 @@ interface MusicRepository {

    /** A persistent worker that can load music in the background. */
    interface IndexingWorker {
+        /** A [Context] required to read device storage */
+        val workerContext: Context
+
+        /** The [CoroutineScope] to perform coroutine music loading work on. */
+        val scope: CoroutineScope
+
        /**
         * Request that the music loading process ([index]) should be started. Any prior loads
         * should be canceled.
@ -211,42 +219,22 @@ interface MusicRepository {
    }
 }

-/**
- * Represents the current state of the music loader.
- *
- * @author Alexander Capehart (OxygenCobalt)
- */
-sealed interface IndexingState {
-    /**
-     * Music loading is on-going.
-     *
-     * @param progress The current progress of the music loading.
-     */
-    data class Indexing(val progress: IndexingProgress) : IndexingState
-
-    /**
-     * Music loading has completed.
-     *
-     * @param error If music loading has failed, the error that occurred will be here. Otherwise, it
-     *   will be null.
-     */
-    data class Completed(val error: Exception?) : IndexingState
-}
-
 class MusicRepositoryImpl
@Inject
 constructor(
-    @ApplicationContext private val context: Context,
-    private val cache: MutableCache,
-    private val storedPlaylists: StoredPlaylists,
-    private val settingCovers: SettingCovers,
+    private val cacheRepository: CacheRepository,
+    private val mediaStoreExtractor: MediaStoreExtractor,
+    private val tagExtractor: TagExtractor,
+    private val deviceLibraryFactory: DeviceLibrary.Factory,
+    private val userLibraryFactory: UserLibrary.Factory,
    private val musicSettings: MusicSettings
 ) : MusicRepository {
    private val updateListeners = mutableListOf<MusicRepository.UpdateListener>()
    private val indexingListeners = mutableListOf<MusicRepository.IndexingListener>()
-    @Volatile private var indexingWorker: IndexingWorker? = null
+    @Volatile private var indexingWorker: MusicRepository.IndexingWorker? = null

-    @Volatile override var library: MutableLibrary? = null
+    @Volatile override var deviceLibrary: DeviceLibrary? = null
+    @Volatile override var userLibrary: MutableUserLibrary? = null
    @Volatile private var previousCompletedState: IndexingState.Completed? = null
    @Volatile private var currentIndexingState: IndexingState? = null
    override val indexingState: IndexingState?
@ -283,7 +271,7 @@ constructor(
    }

    @Synchronized
-    override fun registerWorker(worker: IndexingWorker) {
+    override fun registerWorker(worker: MusicRepository.IndexingWorker) {
        if (indexingWorker != null) {
            L.w("Worker is already registered")
            return
@ -293,7 +281,7 @@ constructor(
    }

    @Synchronized
-    override fun unregisterWorker(worker: IndexingWorker) {
+    override fun unregisterWorker(worker: MusicRepository.IndexingWorker) {
        if (indexingWorker !== worker) {
            L.w("Given worker did not match current worker")
            return
@ -305,51 +293,41 @@ constructor(

    @Synchronized
    override fun find(uid: Music.UID) =
-        (library?.run {
-            findSong(uid)
-                ?: findAlbum(uid)
-                ?: findArtist(uid)
-                ?: findGenre(uid)
-                ?: findPlaylist(uid)
-        })
+        (deviceLibrary?.run { findSong(uid) ?: findAlbum(uid) ?: findArtist(uid) ?: findGenre(uid) }
+            ?: userLibrary?.findPlaylist(uid))

    override suspend fun createPlaylist(name: String, songs: List<Song>) {
-        val library = synchronized(this) { library ?: return }
+        val userLibrary = synchronized(this) { userLibrary ?: return }
        L.d("Creating playlist $name with ${songs.size} songs")
-        val newLibrary = library.createPlaylist(name, songs)
-        synchronized(this) { this.library = newLibrary }
+        userLibrary.createPlaylist(name, songs)
        withContext(Dispatchers.Main) { dispatchLibraryChange(device = false, user = true) }
    }

    override suspend fun renamePlaylist(playlist: Playlist, name: String) {
-        val library = synchronized(this) { library ?: return }
+        val userLibrary = synchronized(this) { userLibrary ?: return }
        L.d("Renaming $playlist to $name")
-        val newLibrary = library.renamePlaylist(playlist, name)
-        synchronized(this) { this.library = newLibrary }
+        userLibrary.renamePlaylist(playlist, name)
        withContext(Dispatchers.Main) { dispatchLibraryChange(device = false, user = true) }
    }

    override suspend fun deletePlaylist(playlist: Playlist) {
-        val library = synchronized(this) { library ?: return }
+        val userLibrary = synchronized(this) { userLibrary ?: return }
        L.d("Deleting $playlist")
-        val newLibrary = library.deletePlaylist(playlist)
-        synchronized(this) { this.library = newLibrary }
+        userLibrary.deletePlaylist(playlist)
        withContext(Dispatchers.Main) { dispatchLibraryChange(device = false, user = true) }
    }

    override suspend fun addToPlaylist(songs: List<Song>, playlist: Playlist) {
-        val library = synchronized(this) { library ?: return }
+        val userLibrary = synchronized(this) { userLibrary ?: return }
        L.d("Adding ${songs.size} songs to $playlist")
-        val newLibrary = library.addToPlaylist(playlist, songs)
-        synchronized(this) { this.library = newLibrary }
+        userLibrary.addToPlaylist(playlist, songs)
        withContext(Dispatchers.Main) { dispatchLibraryChange(device = false, user = true) }
    }

    override suspend fun rewritePlaylist(playlist: Playlist, songs: List<Song>) {
-        val library = synchronized(this) { library ?: return }
+        val userLibrary = synchronized(this) { userLibrary ?: return }
        L.d("Rewriting $playlist with ${songs.size} songs")
-        val newLibrary = library.rewritePlaylist(playlist, songs)
-        synchronized(this) { this.library = newLibrary }
+        userLibrary.rewritePlaylist(playlist, songs)
        withContext(Dispatchers.Main) { dispatchLibraryChange(device = false, user = true) }
    }

@ -359,53 +337,241 @@ constructor(
        indexingWorker?.requestIndex(withCache)
    }

-    override suspend fun index(worker: IndexingWorker, withCache: Boolean) {
-        L.d("Begin index [cache=$withCache]")
+    override fun index(worker: MusicRepository.IndexingWorker, withCache: Boolean) =
+        worker.scope.launch { indexWrapper(worker.workerContext, this, withCache) }
+
+    private suspend fun indexWrapper(context: Context, scope: CoroutineScope, withCache: Boolean) {
        try {
-            indexImpl(withCache)
+            indexImpl(context, scope, withCache)
        } catch (e: CancellationException) {
            // Got cancelled, propagate upwards to top-level co-routine.
            L.d("Loading routine was cancelled")
            throw e
        } catch (e: Exception) {
            // Music loading process failed due to something we have not handled.
+            // TODO: Still want to display this error eventually
            L.e("Music indexing failed")
            L.e(e.stackTraceToString())
            emitIndexingCompletion(e)
        }
    }

-    private suspend fun indexImpl(withCache: Boolean) {
+    private suspend fun indexImpl(context: Context, scope: CoroutineScope, withCache: Boolean) {
+        // TODO: Find a way to break up this monster of a method, preferably as another class.
+
+        val start = System.currentTimeMillis()
+        // Make sure we have permissions before going forward. Theoretically this would be better
+        // done at the UI level, but that intertwines logic and display too much.
+        if (ContextCompat.checkSelfPermission(context, PERMISSION_READ_AUDIO) ==
+            PackageManager.PERMISSION_DENIED) {
+            L.e("Permissions were not granted")
+            throw NoAudioPermissionException()
+        }
+
        // Obtain configuration information
+        val constraints =
+            MediaStoreExtractor.Constraints(musicSettings.excludeNonMusic, musicSettings.musicDirs)
        val separators = Separators.from(musicSettings.separators)
        val nameFactory =
            if (musicSettings.intelligentSorting) {
-                Naming.intelligent()
+                Name.Known.IntelligentFactory
            } else {
-                Naming.simple()
+                Name.Known.SimpleFactory
            }
-        val locations = musicSettings.musicLocations
-        val withHidden = musicSettings.withHidden

-        val currentRevision = musicSettings.revision
-        val newRevision = currentRevision?.takeIf { withCache } ?: UUID.randomUUID()
-        val cache = if (withCache) cache else WriteOnlyMutableCache(cache)
-        val covers = settingCovers.mutate(context, newRevision)
-        val storage = Storage(cache, covers, storedPlaylists)
-        val interpretation = Interpretation(nameFactory, separators, withHidden)
-        val result =
-            Musikr.new(context, storage, interpretation).run(locations, ::emitIndexingProgress)
-        // Music loading completed, update the revision right now so we re-use this work
-        // later.
-        musicSettings.revision = newRevision
-        // Deliver the library to the rest of the app
-        // This will more or less block until all required item translation and
-        // cleanup finishes.
-        emitLibrary(result.library)
-        // Clean up old data that is now impossible for the app to be using.
-        result.cleanup()
-        // Finish up loading.
+        // Begin with querying MediaStore and the music cache. The former is needed for Auxio
+        // to figure out what songs are (probably) on the device, and the latter will be needed
+        // for discovery (described later). These have no shared state, so they are done in
+        // parallel.
+        L.d("Starting MediaStore query")
+        emitIndexingProgress(IndexingProgress.Indeterminate)
+
+        val mediaStoreQueryJob =
+            scope.async {
+                val query =
+                    try {
+                        mediaStoreExtractor.query(constraints)
+                    } catch (e: Exception) {
+                        // Normally, errors in an async call immediately bubble up to the Looper
+                        // and crash the app. Thus, we have to wrap any error into a Result
+                        // and then manually forward it to the try block that indexImpl is
+                        // called from.
+                        return@async Result.failure(e)
+                    }
+                Result.success(query)
+            }
+        // Since this main thread is a co-routine, we can do operations in parallel in a way
+        // identical to calling async.
+        val cache =
+            if (withCache) {
+                L.d("Reading cache")
+                cacheRepository.readCache()
+            } else {
+                null
+            }
+        L.d("Awaiting MediaStore query")
+        val query = mediaStoreQueryJob.await().getOrThrow()
+
+        // We now have all the information required to start the "discovery" process. This
+        // is the point at which Auxio starts scanning each file given from MediaStore and
+        // transforming it into a music library. MediaStore normally
+        L.d("Starting discovery")
+        val incompleteSongs = Channel<RawSong>(Channel.UNLIMITED) // Not fully populated w/metadata
+        val completeSongs = Channel<RawSong>(Channel.UNLIMITED) // Populated with quality metadata
+        val processedSongs = Channel<RawSong>(Channel.UNLIMITED) // Transformed into SongImpl
+
+        // MediaStoreExtractor discovers all music on the device, and forwards them to either
+        // DeviceLibrary if cached metadata exists for it, or TagExtractor if cached metadata
+        // does not exist. In the latter situation, it also applies it's own (inferior) metadata.
+        L.d("Starting MediaStore discovery")
+        val mediaStoreJob =
+            scope.async {
+                try {
+                    mediaStoreExtractor.consume(query, cache, incompleteSongs, completeSongs)
+                } catch (e: Exception) {
+                    // To prevent a deadlock, we want to close the channel with an exception
+                    // to cascade to and cancel all other routines before finally bubbling up
+                    // to the main extractor loop.
+                    L.e("MediaStore extraction failed: $e")
+                    incompleteSongs.close(
+                        Exception("MediaStore extraction failed: ${e.stackTraceToString()}"))
+                    return@async
+                }
+                incompleteSongs.close()
+            }
+
+        // TagExtractor takes the incomplete songs from MediaStoreExtractor, parses up-to-date
+        // metadata for them, and then forwards it to DeviceLibrary.
+        L.d("Starting tag extraction")
+        val tagJob =
+            scope.async {
+                try {
+                    tagExtractor.consume(incompleteSongs, completeSongs)
+                } catch (e: Exception) {
+                    L.e("Tag extraction failed: $e")
+                    completeSongs.close(
+                        Exception("Tag extraction failed: ${e.stackTraceToString()}"))
+                    return@async
+                }
+                completeSongs.close()
+            }
+
+        // DeviceLibrary constructs music parent instances as song information is provided,
+        // and then forwards them to the primary loading loop.
+        L.d("Starting DeviceLibrary creation")
+        val deviceLibraryJob =
+            scope.async(Dispatchers.Default) {
+                val deviceLibrary =
+                    try {
+                        deviceLibraryFactory.create(
+                            completeSongs, processedSongs, separators, nameFactory)
+                    } catch (e: Exception) {
+                        L.e("DeviceLibrary creation failed: $e")
+                        processedSongs.close(
+                            Exception("DeviceLibrary creation failed: ${e.stackTraceToString()}"))
+                        return@async Result.failure(e)
+                    }
+                processedSongs.close()
+                Result.success(deviceLibrary)
+            }
+
+        // We could keep track of a total here, but we also need to collate this RawSong information
+        // for when we write the cache later on in the finalization step.
+        val rawSongs = LinkedList<RawSong>()
+        // Use a longer timeout so that dependent components can timeout and throw errors that
+        // provide more context than if we timed out here.
+        processedSongs.forEachWithTimeout(DEFAULT_TIMEOUT * 2) {
+            rawSongs.add(it)
+            // Since discovery takes up the bulk of the music loading process, we switch to
+            // indicating a defined amount of loaded songs in comparison to the projected amount
+            // of songs that were queried.
+            emitIndexingProgress(IndexingProgress.Songs(rawSongs.size, query.projectedTotal))
+        }
+
+        withTimeout(DEFAULT_TIMEOUT) {
+            mediaStoreJob.await()
+            tagJob.await()
+        }
+
+        // Deliberately done after the involved initialization step to make it less likely
+        // that the short-circuit occurs so quickly as to break the UI.
+        // TODO: Do not error, instead just wipe the entire library.
+        if (rawSongs.isEmpty()) {
+            L.e("Music library was empty")
+            throw NoMusicException()
+        }
+
+        // Now that the library is effectively loaded, we can start the finalization step, which
+        // involves writing new cache information and creating more music data that is derived
+        // from the library (e.g playlists)
+        L.d("Discovered ${rawSongs.size} songs, starting finalization")
+
+        // We have no idea how long the cache will take, and the playlist construction
+        // will be too fast to indicate, so switch back to an indeterminate state.
+        emitIndexingProgress(IndexingProgress.Indeterminate)
+
+        // The UserLibrary job is split into a query and construction step, a la MediaStore.
+        // This way, we can start working on playlists even as DeviceLibrary might still be
+        // working on parent information.
+        L.d("Starting UserLibrary query")
+        val userLibraryQueryJob =
+            scope.async {
+                val rawPlaylists =
+                    try {
+                        userLibraryFactory.query()
+                    } catch (e: Exception) {
+                        return@async Result.failure(e)
+                    }
+                Result.success(rawPlaylists)
+            }
+
+        // The cache might not exist, or we might have encountered a song not present in it.
+        // Both situations require us to rewrite the cache in bulk. This is also done parallel
+        // since the playlist read will probably take some time.
+        // TODO: Read/write from the cache incrementally instead of in bulk?
+        if (cache == null || cache.invalidated) {
+            L.d("Writing cache [why=${cache?.invalidated}]")
+            cacheRepository.writeCache(rawSongs)
+        }
+
+        // Create UserLibrary once we finally get the required components for it.
+        L.d("Awaiting UserLibrary query")
+        val rawPlaylists = userLibraryQueryJob.await().getOrThrow()
+        L.d("Awaiting DeviceLibrary creation")
+        val deviceLibrary = deviceLibraryJob.await().getOrThrow()
+        L.d("Starting UserLibrary creation")
+        val userLibrary = userLibraryFactory.create(rawPlaylists, deviceLibrary, nameFactory)
+
+        // Loading process is functionally done, indicate such
+        L.d(
+            "Successfully indexed music library [device=$deviceLibrary " +
+                "user=$userLibrary time=${System.currentTimeMillis() - start}]")
        emitIndexingCompletion(null)
+
+        val deviceLibraryChanged: Boolean
+        val userLibraryChanged: Boolean
+        // We want to make sure that all reads and writes are synchronized due to the sheer
+        // amount of consumers of MusicRepository.
+        // TODO: Would Atomics not be a better fit here?
+        synchronized(this) {
+            // It's possible that this reload might have changed nothing, so make sure that
+            // hasn't happened before dispatching a change to all consumers.
+            deviceLibraryChanged = this.deviceLibrary != deviceLibrary
+            userLibraryChanged = this.userLibrary != userLibrary
+            if (!deviceLibraryChanged && !userLibraryChanged) {
+                L.d("Library has not changed, skipping update")
+                return
+            }
+
+            this.deviceLibrary = deviceLibrary
+            this.userLibrary = userLibrary
+        }
+
+        // Consumers expect their updates to be on the main thread (notably PlaybackService),
+        // so switch to it.
+        withContext(Dispatchers.Main) {
+            dispatchLibraryChange(deviceLibraryChanged, userLibraryChanged)
+        }
    }

    private suspend fun emitIndexingProgress(progress: IndexingProgress) {
@ -418,39 +584,6 @@ constructor(
        }
    }

-    private suspend fun emitLibrary(newLibrary: MutableLibrary) {
-        val deviceLibraryChanged: Boolean
-        val userLibraryChanged: Boolean
-        // We want to make sure that all reads and writes are synchronized due to the sheer
-        // amount of consumers of MusicRepository.
-        synchronized(this) {
-            // It's possible that this reload might have changed nothing, so make sure that
-            // hasn't happened before dispatching a change to all consumers.
-
-            // This is an old compat shim back when device library and user library were different
-            // thinks. For the sake of avoiding drastic changes, it sticks around.
-            // TODO: Remove this once you start work on kindred.
-            deviceLibraryChanged =
-                this.library?.songs != newLibrary.songs ||
-                    this.library?.albums != newLibrary.albums ||
-                    this.library?.artists != newLibrary.artists ||
-                    this.library?.genres != newLibrary.genres
-            userLibraryChanged = this.library?.playlists != newLibrary.playlists
-            if (!deviceLibraryChanged && !userLibraryChanged) {
-                L.d("Library has not changed, skipping update")
-                return
-            }
-
-            this.library = newLibrary
-        }
-
-        // Consumers expect their updates to be on the main thread (notably PlaybackService),
-        // so switch to it.
-        withContext(Dispatchers.Main) {
-            dispatchLibraryChange(deviceLibraryChanged, userLibraryChanged)
-        }
-    }
-
    private suspend fun emitIndexingCompletion(error: Exception?) {
        yield()
        synchronized(this) {
--- a/app/src/main/java/org/oxycblt/auxio/music/MusicSettings.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/MusicSettings.kt
@ -21,11 +21,11 @@ package org.oxycblt.auxio.music
 import android.content.Context
 import androidx.core.content.edit
 import dagger.hilt.android.qualifiers.ApplicationContext
-import java.util.UUID
 import javax.inject.Inject
 import org.oxycblt.auxio.R
+import org.oxycblt.auxio.music.dirs.MusicDirectories
+import org.oxycblt.auxio.music.fs.DocumentPathFactory
 import org.oxycblt.auxio.settings.Settings
-import org.oxycblt.musikr.fs.MusicLocation
 import timber.log.Timber as L

 /**
@ -34,14 +34,10 @@ import timber.log.Timber as L
 * @author Alexander Capehart (OxygenCobalt)
 */
 interface MusicSettings : Settings<MusicSettings.Listener> {
-    /** The current library revision. */
-    var revision: UUID?
-    /** The locations of music to load. */
-    var musicLocations: List<MusicLocation>
+    /** The configuration on how to handle particular directories in the music library. */
+    var musicDirs: MusicDirectories
    /** Whether to exclude non-music audio files from the music library. */
    val excludeNonMusic: Boolean
-    /** Whether to ignore hidden files and directories during music loading. */
-    val withHidden: Boolean
    /** Whether to be actively watching for changes in the music library. */
    val shouldBeObserving: Boolean
    /** A [String] of characters representing the desired characters to denote multi-value tags. */
@ -50,8 +46,6 @@ interface MusicSettings : Settings<MusicSettings.Listener> {
    val intelligentSorting: Boolean

    interface Listener {
-        /** Called when the current music locations changed. */
-        fun onMusicLocationsChanged() {}
        /** Called when a setting controlling how music is loaded has changed. */
        fun onIndexingSettingChanged() {}
        /** Called when the [shouldBeObserving] configuration has changed. */
@ -59,45 +53,35 @@ interface MusicSettings : Settings<MusicSettings.Listener> {
    }
 }

-class MusicSettingsImpl @Inject constructor(@ApplicationContext private val context: Context) :
-    Settings.Impl<MusicSettings.Listener>(context), MusicSettings {
-
-    override var revision: UUID?
-        get() =
-            sharedPreferences
-                .getString(getString(R.string.set_key_library_revision), null)
-                ?.let(UUID::fromString)
-        set(value) {
-            sharedPreferences.edit {
-                putString(getString(R.string.set_key_library_revision), value.toString())
-                apply()
-            }
-        }
-
-    override var musicLocations: List<MusicLocation>
+class MusicSettingsImpl
+@Inject
+constructor(
+    @ApplicationContext context: Context,
+    private val documentPathFactory: DocumentPathFactory
+) : Settings.Impl<MusicSettings.Listener>(context), MusicSettings {
+    override var musicDirs: MusicDirectories
        get() {
-            val locations =
-                sharedPreferences.getString(getString(R.string.set_key_music_locations), null)
-                    ?: return emptyList()
-            return MusicLocation.existing(context, locations)
+            val dirs =
+                (sharedPreferences.getStringSet(getString(R.string.set_key_music_dirs), null)
+                        ?: emptySet())
+                    .mapNotNull(documentPathFactory::fromDocumentId)
+            return MusicDirectories(
+                dirs,
+                sharedPreferences.getBoolean(getString(R.string.set_key_music_dirs_include), false))
        }
        set(value) {
            sharedPreferences.edit {
-                putString(
-                    getString(R.string.set_key_music_locations), MusicLocation.toString(value))
-                commit()
-                // Sometimes changing this setting just won't actually trigger the listener.
-                // Only this one. No idea why.
-                listener?.onMusicLocationsChanged()
+                putStringSet(
+                    getString(R.string.set_key_music_dirs),
+                    value.dirs.map(documentPathFactory::toDocumentId).toSet())
+                putBoolean(getString(R.string.set_key_music_dirs_include), value.shouldInclude)
+                apply()
            }
        }

    override val excludeNonMusic: Boolean
        get() = sharedPreferences.getBoolean(getString(R.string.set_key_exclude_non_music), true)

-    override val withHidden: Boolean
-        get() = sharedPreferences.getBoolean(getString(R.string.set_key_with_hidden), false)
-
    override val shouldBeObserving: Boolean
        get() = sharedPreferences.getBoolean(getString(R.string.set_key_observing), false)

@ -119,14 +103,11 @@ class MusicSettingsImpl @Inject constructor(@ApplicationContext private val cont
        // TODO: Differentiate "hard reloads" (Need the cache) and "Soft reloads"
        //  (just need to manipulate data)
        when (key) {
-            getString(R.string.set_key_music_locations) -> {
-                L.d("Dispatching music locations change")
-                listener.onMusicLocationsChanged()
-            }
+            getString(R.string.set_key_exclude_non_music),
+            getString(R.string.set_key_music_dirs),
+            getString(R.string.set_key_music_dirs_include),
            getString(R.string.set_key_separators),
-            getString(R.string.set_key_auto_sort_names),
-            getString(R.string.set_key_with_hidden),
-            getString(R.string.set_key_exclude_non_music) -> {
+            getString(R.string.set_key_auto_sort_names) -> {
                L.d("Dispatching indexing setting change for $key")
                listener.onIndexingSettingChanged()
            }
--- a/app/src/main/java/org/oxycblt/auxio/music/MusicType.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/MusicType.kt
@ -27,10 +27,15 @@ import org.oxycblt.auxio.R
 * @author Alexander Capehart (OxygenCobalt)
 */
 enum class MusicType {
+    /** @see Song */
    SONGS,
+    /** @see Album */
    ALBUMS,
+    /** @see Artist */
    ARTISTS,
+    /** @see Genre */
    GENRES,
+    /** @see Playlist */
    PLAYLISTS;

    /**
--- a/app/src/main/java/org/oxycblt/auxio/music/MusicUtil.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/MusicUtil.kt
@ -1,173 +0,0 @@
-/*
- * Copyright (c) 2024 Auxio Project
- * MusicUtil.kt is part of Auxio.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.music
-
-import android.content.Context
-import java.text.ParseException
-import java.text.SimpleDateFormat
-import kotlin.math.max
-import org.oxycblt.auxio.R
-import org.oxycblt.auxio.util.concatLocalized
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.fs.Format
-import org.oxycblt.musikr.tag.Date
-import org.oxycblt.musikr.tag.Disc
-import org.oxycblt.musikr.tag.Name
-import org.oxycblt.musikr.tag.Placeholder
-import org.oxycblt.musikr.tag.ReleaseType
-import org.oxycblt.musikr.tag.ReleaseType.Refinement
-import timber.log.Timber
-
-fun Name.resolve(context: Context) =
-    when (this) {
-        is Name.Known -> raw
-        is Name.Unknown ->
-            when (placeholder) {
-                Placeholder.ALBUM -> context.getString(R.string.def_album)
-                Placeholder.ARTIST -> context.getString(R.string.def_artist)
-                Placeholder.GENRE -> context.getString(R.string.def_genre)
-            }
-    }
-
-/**
- * Run [Name.resolve] on each instance in the given list and concatenate them into a [String] in a
- * localized manner.
- *
- * @param context [Context] required
- * @return A concatenated string.
- */
-fun <T : Music> List<T>.resolveNames(context: Context) =
-    concatLocalized(context) { it.name.resolve(context) }
-
-/**
- * Returns if [Music.name] matches for each item in a list. Useful for scenarios where the display
- * information of an item must be compared without a context.
- *
- * @param other The list of items to compare to.
- * @return True if they are the same (by [Music.name]), false otherwise.
- */
-fun <T : Music> List<T>.areNamesTheSame(other: List<T>): Boolean {
-    for (i in 0 until max(size, other.size)) {
-        val a = getOrNull(i) ?: return false
-        val b = other.getOrNull(i) ?: return false
-        if (a.name != b.name) {
-            return false
-        }
-    }
-
-    return true
-}
-
-/**
- * Resolve this instance into a human-readable date.
- *
- * @param context [Context] required to get human-readable names.
- * @return If the [Date] has a valid month and year value, a more fine-grained date (ex. "Jan 2020")
- *   will be returned. Otherwise, a plain year value (ex. "2020") is returned. Dates will be
- *   properly localized.
- */
-fun Date.resolve(context: Context) =
-    // Unable to create fine-grained date, just format as a year.
-    month?.let { resolveFineGrained() } ?: context.getString(R.string.fmt_number, year)
-
-private fun Date.resolveFineGrained(): String? {
-    // We can't directly load a date with our own
-    val format = (SimpleDateFormat.getDateInstance() as SimpleDateFormat)
-    format.applyPattern("yyyy-MM")
-    val date =
-        try {
-            format.parse("$year-$month")
-        } catch (e: ParseException) {
-            Timber.e("Unable to parse fine-grained date: $e")
-            return null
-        }
-
-    // Reformat as a readable month and year
-    format.applyPattern("MMM yyyy")
-    return format.format(date)
-}
-
-fun Disc?.resolve(context: Context) =
-    this?.run { context.getString(R.string.fmt_disc_no, number) }
-        ?: context.getString(R.string.def_disc)
-
-/**
- * Resolve this instance into a human-readable date range.
- *
- * @param context [Context] required to get human-readable names.
- * @return If the date has a maximum value, then a `min - max` formatted string will be returned
- *   with the formatted [Date]s of the minimum and maximum dates respectively. Otherwise, the
- *   formatted name of the minimum [Date] will be returned.
- */
-fun Date.Range.resolve(context: Context) =
-    if (min != max) {
-        context.getString(R.string.fmt_date_range, min.resolve(context), max.resolve(context))
-    } else {
-        min.resolve(context)
-    }
-
-fun ReleaseType.resolve(context: Context) =
-    when (this) {
-        is ReleaseType.Album ->
-            when (refinement) {
-                null -> context.getString(R.string.lbl_album)
-                Refinement.LIVE -> context.getString(R.string.lbl_album_live)
-                Refinement.REMIX -> context.getString(R.string.lbl_album_remix)
-            }
-        is ReleaseType.EP ->
-            when (refinement) {
-                null -> context.getString(R.string.lbl_ep)
-                Refinement.LIVE -> context.getString(R.string.lbl_ep_live)
-                Refinement.REMIX -> context.getString(R.string.lbl_ep_remix)
-            }
-        is ReleaseType.Single ->
-            when (refinement) {
-                null -> context.getString(R.string.lbl_single)
-                Refinement.LIVE -> context.getString(R.string.lbl_single_live)
-                Refinement.REMIX -> context.getString(R.string.lbl_single_remix)
-            }
-        is ReleaseType.Compilation ->
-            when (refinement) {
-                null -> context.getString(R.string.lbl_compilation)
-                Refinement.LIVE -> context.getString(R.string.lbl_compilation_live)
-                Refinement.REMIX -> context.getString(R.string.lbl_compilation_remix)
-            }
-        is ReleaseType.Soundtrack -> context.getString(R.string.lbl_soundtrack)
-        is ReleaseType.Mix -> context.getString(R.string.lbl_mix)
-        is ReleaseType.Mixtape -> context.getString(R.string.lbl_mixtape)
-        is ReleaseType.Demo -> context.getString(R.string.lbl_demo)
-    }
-
-fun Format.resolve(context: Context): String =
-    when (this) {
-        is Format.MPEG3 -> context.getString(R.string.cdc_mp3)
-        is Format.MPEG4 ->
-            containing?.let { context.getString(R.string.cnt_mp4, it.resolve(context)) }
-                ?: context.getString(R.string.cdc_mp4)
-        is Format.AAC -> context.getString(R.string.cdc_aac)
-        is Format.ALAC -> context.getString(R.string.cdc_alac)
-        is Format.Ogg ->
-            containing?.let { context.getString(R.string.cnt_ogg, it.resolve(context)) }
-                ?: context.getString(R.string.cdc_ogg)
-        is Format.Opus -> context.getString(R.string.cdc_opus)
-        is Format.Vorbis -> context.getString(R.string.cdc_vorbis)
-        is Format.FLAC -> context.getString(R.string.cdc_flac)
-        is Format.Wav -> context.getString(R.string.cdc_wav)
-        is Format.Unknown -> extension ?: context.getString(R.string.cdc_unknown)
-    }
--- a/app/src/main/java/org/oxycblt/auxio/music/MusicViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/MusicViewModel.kt
@ -18,12 +18,10 @@
 
 package org.oxycblt.auxio.music

-import android.content.Context
 import android.net.Uri
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
-import dagger.hilt.android.qualifiers.ApplicationContext
 import javax.inject.Inject
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
@ -31,15 +29,10 @@ import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.launch
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.list.ListSettings
+import org.oxycblt.auxio.music.external.ExportConfig
+import org.oxycblt.auxio.music.external.ExternalPlaylistManager
 import org.oxycblt.auxio.util.Event
 import org.oxycblt.auxio.util.MutableEvent
-import org.oxycblt.musikr.Album
-import org.oxycblt.musikr.Artist
-import org.oxycblt.musikr.Genre
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.playlist.ExportConfig
-import org.oxycblt.musikr.playlist.ExternalPlaylistManager
 import timber.log.Timber as L

 /**
@ -51,11 +44,10 @@ import timber.log.Timber as L
 class MusicViewModel
@Inject
 constructor(
-    @ApplicationContext context: Context,
    private val listSettings: ListSettings,
-    private val musicRepository: MusicRepository
+    private val musicRepository: MusicRepository,
+    private val externalPlaylistManager: ExternalPlaylistManager
 ) : ViewModel(), MusicRepository.UpdateListener, MusicRepository.IndexingListener {
-    private val externalPlaylistManager = ExternalPlaylistManager.from(context)

    private val _indexingState = MutableStateFlow<IndexingState?>(null)

@ -93,14 +85,14 @@ constructor(

    override fun onMusicChanges(changes: MusicRepository.Changes) {
        if (!changes.deviceLibrary) return
-        val library = musicRepository.library ?: return
+        val deviceLibrary = musicRepository.deviceLibrary ?: return
        _statistics.value =
            Statistics(
-                library.songs.size,
-                library.albums.size,
-                library.artists.size,
-                library.genres.size,
-                library.songs.sumOf { it.durationMs })
+                deviceLibrary.songs.size,
+                deviceLibrary.albums.size,
+                deviceLibrary.artists.size,
+                deviceLibrary.genres.size,
+                deviceLibrary.songs.sumOf { it.durationMs })
        L.d("Updated statistics: ${_statistics.value}")
    }

@ -170,10 +162,10 @@ constructor(
                    return@launch
                }

-                val library = musicRepository.library ?: return@launch
+                val deviceLibrary = musicRepository.deviceLibrary ?: return@launch
                val songs =
                    importedPlaylist.paths.mapNotNull {
-                        it.firstNotNullOfOrNull(library::findSongByPath)
+                        it.firstNotNullOfOrNull(deviceLibrary::findSongByPath)
                    }

                if (songs.isEmpty()) {
--- a/app/src/main/java/org/oxycblt/auxio/music/cache/CacheDatabase.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/cache/CacheDatabase.kt
@ -0,0 +1,187 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * CacheDatabase.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.music.cache
+
+import androidx.room.Dao
+import androidx.room.Database
+import androidx.room.Entity
+import androidx.room.Insert
+import androidx.room.PrimaryKey
+import androidx.room.Query
+import androidx.room.RoomDatabase
+import androidx.room.TypeConverter
+import androidx.room.TypeConverters
+import org.oxycblt.auxio.music.device.RawSong
+import org.oxycblt.auxio.music.info.Date
+import org.oxycblt.auxio.music.metadata.correctWhitespace
+import org.oxycblt.auxio.music.metadata.splitEscaped
+
+@Database(entities = [CachedSong::class], version = 49, exportSchema = false)
+abstract class CacheDatabase : RoomDatabase() {
+    abstract fun cachedSongsDao(): CachedSongsDao
+}
+
+@Dao
+interface CachedSongsDao {
+    @Query("SELECT * FROM CachedSong") suspend fun readSongs(): List<CachedSong>
+
+    @Query("DELETE FROM CachedSong") suspend fun nukeSongs()
+
+    @Insert suspend fun insertSongs(songs: List<CachedSong>)
+}
+
+@Entity
+@TypeConverters(CachedSong.Converters::class)
+data class CachedSong(
+    /**
+     * The ID of the [RawSong]'s audio file, obtained from MediaStore. Note that this ID is highly
+     * unstable and should only be used for accessing the audio file.
+     */
+    @PrimaryKey var mediaStoreId: Long,
+    /** @see RawSong.dateAdded */
+    var dateAdded: Long,
+    /** The latest date the [RawSong]'s audio file was modified, as a unix epoch timestamp. */
+    var dateModified: Long,
+    /** @see RawSong.size */
+    var size: Long? = null,
+    /** @see RawSong */
+    var durationMs: Long,
+    /** @see RawSong.replayGainTrackAdjustment */
+    val replayGainTrackAdjustment: Float? = null,
+    /** @see RawSong.replayGainAlbumAdjustment */
+    val replayGainAlbumAdjustment: Float? = null,
+    /** @see RawSong.musicBrainzId */
+    var musicBrainzId: String? = null,
+    /** @see RawSong.name */
+    var name: String,
+    /** @see RawSong.sortName */
+    var sortName: String? = null,
+    /** @see RawSong.track */
+    var track: Int? = null,
+    /** @see RawSong.name */
+    var disc: Int? = null,
+    /** @See RawSong.subtitle */
+    var subtitle: String? = null,
+    /** @see RawSong.date */
+    var date: Date? = null,
+    /** @see RawSong.coverPerceptualHash */
+    var coverPerceptualHash: String? = null,
+    /** @see RawSong.albumMusicBrainzId */
+    var albumMusicBrainzId: String? = null,
+    /** @see RawSong.albumName */
+    var albumName: String,
+    /** @see RawSong.albumSortName */
+    var albumSortName: String? = null,
+    /** @see RawSong.releaseTypes */
+    var releaseTypes: List<String> = listOf(),
+    /** @see RawSong.artistMusicBrainzIds */
+    var artistMusicBrainzIds: List<String> = listOf(),
+    /** @see RawSong.artistNames */
+    var artistNames: List<String> = listOf(),
+    /** @see RawSong.artistSortNames */
+    var artistSortNames: List<String> = listOf(),
+    /** @see RawSong.albumArtistMusicBrainzIds */
+    var albumArtistMusicBrainzIds: List<String> = listOf(),
+    /** @see RawSong.albumArtistNames */
+    var albumArtistNames: List<String> = listOf(),
+    /** @see RawSong.albumArtistSortNames */
+    var albumArtistSortNames: List<String> = listOf(),
+    /** @see RawSong.genreNames */
+    var genreNames: List<String> = listOf()
+) {
+    fun copyToRaw(rawSong: RawSong) {
+        rawSong.musicBrainzId = musicBrainzId
+        rawSong.name = name
+        rawSong.sortName = sortName
+
+        rawSong.size = size
+        rawSong.durationMs = durationMs
+
+        rawSong.replayGainTrackAdjustment = replayGainTrackAdjustment
+        rawSong.replayGainAlbumAdjustment = replayGainAlbumAdjustment
+
+        rawSong.track = track
+        rawSong.disc = disc
+        rawSong.subtitle = subtitle
+        rawSong.date = date
+
+        rawSong.coverPerceptualHash = coverPerceptualHash
+
+        rawSong.albumMusicBrainzId = albumMusicBrainzId
+        rawSong.albumName = albumName
+        rawSong.albumSortName = albumSortName
+        rawSong.releaseTypes = releaseTypes
+
+        rawSong.artistMusicBrainzIds = artistMusicBrainzIds
+        rawSong.artistNames = artistNames
+        rawSong.artistSortNames = artistSortNames
+
+        rawSong.albumArtistMusicBrainzIds = albumArtistMusicBrainzIds
+        rawSong.albumArtistNames = albumArtistNames
+        rawSong.albumArtistSortNames = albumArtistSortNames
+
+        rawSong.genreNames = genreNames
+    }
+
+    object Converters {
+        @TypeConverter
+        fun fromMultiValue(values: List<String>) =
+            values.joinToString(";") { it.replace(";", "\\;") }
+
+        @TypeConverter
+        fun toMultiValue(string: String) = string.splitEscaped { it == ';' }.correctWhitespace()
+
+        @TypeConverter fun fromDate(date: Date?) = date?.toString()
+
+        @TypeConverter fun toDate(string: String?) = string?.let(Date::from)
+    }
+
+    companion object {
+        fun fromRaw(rawSong: RawSong) =
+            CachedSong(
+                mediaStoreId =
+                    requireNotNull(rawSong.mediaStoreId) { "Invalid raw: No MediaStore ID" },
+                dateAdded = requireNotNull(rawSong.dateAdded) { "Invalid raw: No date added" },
+                dateModified =
+                    requireNotNull(rawSong.dateModified) { "Invalid raw: No date modified" },
+                musicBrainzId = rawSong.musicBrainzId,
+                name = requireNotNull(rawSong.name) { "Invalid raw: No name" },
+                sortName = rawSong.sortName,
+                size = rawSong.size,
+                durationMs = requireNotNull(rawSong.durationMs) { "Invalid raw: No duration" },
+                replayGainTrackAdjustment = rawSong.replayGainTrackAdjustment,
+                replayGainAlbumAdjustment = rawSong.replayGainAlbumAdjustment,
+                track = rawSong.track,
+                disc = rawSong.disc,
+                subtitle = rawSong.subtitle,
+                date = rawSong.date,
+                coverPerceptualHash = rawSong.coverPerceptualHash,
+                albumMusicBrainzId = rawSong.albumMusicBrainzId,
+                albumName = requireNotNull(rawSong.albumName) { "Invalid raw: No album name" },
+                albumSortName = rawSong.albumSortName,
+                releaseTypes = rawSong.releaseTypes,
+                artistMusicBrainzIds = rawSong.artistMusicBrainzIds,
+                artistNames = rawSong.artistNames,
+                artistSortNames = rawSong.artistSortNames,
+                albumArtistMusicBrainzIds = rawSong.albumArtistMusicBrainzIds,
+                albumArtistNames = rawSong.albumArtistNames,
+                albumArtistSortNames = rawSong.albumArtistSortNames,
+                genreNames = rawSong.genreNames)
+    }
+}
--- a/app/src/main/java/org/oxycblt/auxio/music/shim/MusikrShimModule.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/shim/MusikrShimModule.kt
@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2025 Auxio Project
- * MusikrShimModule.kt is part of Auxio.
+ * Copyright (c) 2023 Auxio Project
+ * CacheModule.kt is part of Auxio.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
@ -16,31 +16,34 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-package org.oxycblt.auxio.music.shim
+package org.oxycblt.auxio.music.cache

 import android.content.Context
+import androidx.room.Room
+import dagger.Binds
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
 import dagger.hilt.android.qualifiers.ApplicationContext
 import dagger.hilt.components.SingletonComponent
 import javax.inject.Singleton
-import org.oxycblt.musikr.cache.MutableCache
-import org.oxycblt.musikr.cache.db.MutableDBCache
-import org.oxycblt.musikr.playlist.db.StoredPlaylists

@Module
@InstallIn(SingletonComponent::class)
-class MusikrShimModule {
-    @Singleton
-    @Provides
-    fun cache(@ApplicationContext context: Context): MutableCache = MutableDBCache.from(context)
-
-    @Singleton
-    @Provides
-    fun storedPlaylists(@ApplicationContext context: Context) = StoredPlaylists.from(context)
-
-    @Provides
-    fun updateTrackerFactory(@ApplicationContext context: Context): UpdateTrackerFactory =
-        UpdateTrackerFactoryImpl(context)
+interface CacheModule {
+    @Binds fun cacheRepository(cacheRepository: CacheRepositoryImpl): CacheRepository
+}
+
+@Module
+@InstallIn(SingletonComponent::class)
+class CacheRoomModule {
+    @Singleton
+    @Provides
+    fun database(@ApplicationContext context: Context) =
+        Room.databaseBuilder(
+                context.applicationContext, CacheDatabase::class.java, "music_cache.db")
+            .fallbackToDestructiveMigration()
+            .build()
+
+    @Provides fun cachedSongsDao(database: CacheDatabase) = database.cachedSongsDao()
 }
--- a/app/src/main/java/org/oxycblt/auxio/music/cache/CacheRepository.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/cache/CacheRepository.kt
@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2022 Auxio Project
+ * CacheRepository.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.music.cache
+
+import javax.inject.Inject
+import org.oxycblt.auxio.music.device.RawSong
+import timber.log.Timber as L
+
+/**
+ * A repository allowing access to cached metadata obtained in prior music loading operations.
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+interface CacheRepository {
+    /**
+     * Read the current [Cache], if it exists.
+     *
+     * @return The stored [Cache], or null if it could not be obtained.
+     */
+    suspend fun readCache(): Cache?
+
+    /**
+     * Write the list of newly-loaded [RawSong]s to the cache, replacing the prior data.
+     *
+     * @param rawSongs The [rawSongs] to write to the cache.
+     */
+    suspend fun writeCache(rawSongs: List<RawSong>)
+}
+
+class CacheRepositoryImpl @Inject constructor(private val cachedSongsDao: CachedSongsDao) :
+    CacheRepository {
+    override suspend fun readCache(): Cache? =
+        try {
+            // Faster to load the whole database into memory than do a query on each
+            // populate call.
+            val songs = cachedSongsDao.readSongs()
+            L.d("Successfully read ${songs.size} songs from cache")
+            CacheImpl(songs)
+        } catch (e: Exception) {
+            L.e("Unable to load cache database.")
+            L.e(e.stackTraceToString())
+            null
+        }
+
+    override suspend fun writeCache(rawSongs: List<RawSong>) {
+        try {
+            // Still write out whatever data was extracted.
+            cachedSongsDao.nukeSongs()
+            L.d("Successfully deleted old cache")
+            cachedSongsDao.insertSongs(rawSongs.map(CachedSong::fromRaw))
+            L.d("Successfully wrote ${rawSongs.size} songs to cache")
+        } catch (e: Exception) {
+            L.e("Unable to save cache database.")
+            L.e(e.stackTraceToString())
+        }
+    }
+}
+
+/**
+ * A cache of music metadata obtained in prior music loading operations. Obtain an instance with
+ * [CacheRepository].
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+interface Cache {
+    /** Whether this cache has encountered a [RawSong] that did not have a cache entry. */
+    val invalidated: Boolean
+
+    /**
+     * Populate a [RawSong] from a cache entry, if it exists.
+     *
+     * @param rawSong The [RawSong] to populate.
+     * @return true if a cache entry could be applied to [rawSong], false otherwise.
+     */
+    fun populate(rawSong: RawSong): Boolean
+}
+
+private class CacheImpl(cachedSongs: List<CachedSong>) : Cache {
+    private val cacheMap = buildMap {
+        for (cachedSong in cachedSongs) {
+            put(cachedSong.mediaStoreId, cachedSong)
+        }
+    }
+
+    override var invalidated = false
+
+    override fun populate(rawSong: RawSong): Boolean {
+        // For a cached raw song to be used, it must exist within the cache and have matching
+        // addition and modification timestamps. Technically the addition timestamp doesn't
+        // exist, but to safeguard against possible OEM-specific timestamp incoherence, we
+        // check for it anyway.
+        val cachedSong = cacheMap[rawSong.mediaStoreId]
+        if (cachedSong != null &&
+            cachedSong.dateAdded == rawSong.dateAdded &&
+            cachedSong.dateModified == rawSong.dateModified) {
+            cachedSong.copyToRaw(rawSong)
+            return true
+        }
+
+        // We could not populate this song. This means our cache is stale and should be
+        // re-written with newly-loaded music.
+        invalidated = true
+        return false
+    }
+}
--- a/app/src/main/java/org/oxycblt/auxio/music/decision/AddToPlaylistDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/decision/AddToPlaylistDialog.kt
@ -33,10 +33,10 @@ import org.oxycblt.auxio.databinding.DialogMusicChoicesBinding
 import org.oxycblt.auxio.list.ClickableListListener
 import org.oxycblt.auxio.music.MusicViewModel
 import org.oxycblt.auxio.music.PlaylistDecision
+import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.collectImmediately
 import org.oxycblt.auxio.util.navigateSafe
-import org.oxycblt.musikr.Song
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/music/decision/DeletePlaylistDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/decision/DeletePlaylistDialog.kt
@ -29,11 +29,10 @@ import dagger.hilt.android.AndroidEntryPoint
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.DialogDeletePlaylistBinding
 import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.collectImmediately
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Playlist
 import timber.log.Timber as L

 /**
@ -53,9 +52,6 @@ class DeletePlaylistDialog : ViewBindingMaterialDialogFragment<DialogDeletePlayl
        builder
            .setTitle(R.string.lbl_confirm_delete_playlist)
            .setPositiveButton(R.string.lbl_delete) { _, _ ->
-                // Normally the navigateUp will occur after this, which then collides with the
-                // playlist view's navigation. Forcefully navigate up to stop this.
-                findNavController().navigateUp()
                // Now we can delete the playlist for-real this time.
                musicModel.deletePlaylist(
                    unlikelyToBeNull(pickerModel.currentPlaylistToDelete.value), rude = true)
--- a/app/src/main/java/org/oxycblt/auxio/music/decision/ExportPlaylistDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/decision/ExportPlaylistDialog.kt
@ -31,13 +31,12 @@ import dagger.hilt.android.AndroidEntryPoint
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.DialogPlaylistExportBinding
 import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.music.resolve
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.music.external.ExportConfig
+import org.oxycblt.auxio.music.external.M3U
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.collectImmediately
 import org.oxycblt.auxio.util.unlikelyToBeNull
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.playlist.ExportConfig
-import org.oxycblt.musikr.playlist.m3u.M3U
 import timber.log.Timber as L

 /**
--- a/app/src/main/java/org/oxycblt/auxio/music/decision/PlaylistChoiceAdapter.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/decision/PlaylistChoiceAdapter.kt
@ -25,7 +25,6 @@ import org.oxycblt.auxio.list.ClickableListListener
 import org.oxycblt.auxio.list.adapter.FlexibleListAdapter
 import org.oxycblt.auxio.list.adapter.SimpleDiffCallback
 import org.oxycblt.auxio.list.recycler.DialogRecyclerView
-import org.oxycblt.auxio.music.resolve
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.inflater

--- a/app/src/main/java/org/oxycblt/auxio/music/decision/PlaylistPickerViewModel.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/decision/PlaylistPickerViewModel.kt
@ -25,14 +25,14 @@ import javax.inject.Inject
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import org.oxycblt.auxio.R
+import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicRepository
+import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.music.PlaylistDecision
-import org.oxycblt.auxio.music.resolve
-import org.oxycblt.musikr.Music
-import org.oxycblt.musikr.Playlist
-import org.oxycblt.musikr.Song
-import org.oxycblt.musikr.playlist.ExportConfig
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.external.ExportConfig
 import timber.log.Timber as L

 /**
@ -89,13 +89,13 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M

    override fun onMusicChanges(changes: MusicRepository.Changes) {
        var refreshChoicesWith: List<Song>? = null
-        val library = musicRepository.library
-        if (changes.deviceLibrary && library != null) {
+        val deviceLibrary = musicRepository.deviceLibrary
+        if (changes.deviceLibrary && deviceLibrary != null) {
            _currentPendingNewPlaylist.value =
                _currentPendingNewPlaylist.value?.let { pendingPlaylist ->
                    PendingNewPlaylist(
                        pendingPlaylist.preferredName,
-                        pendingPlaylist.songs.mapNotNull { library.findSong(it.uid) },
+                        pendingPlaylist.songs.mapNotNull { deviceLibrary.findSong(it.uid) },
                        pendingPlaylist.template,
                        pendingPlaylist.reason)
                }
@ -104,7 +104,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
            _currentSongsToAdd.value =
                _currentSongsToAdd.value?.let { pendingSongs ->
                    pendingSongs
-                        .mapNotNull { library.findSong(it.uid) }
+                        .mapNotNull { deviceLibrary.findSong(it.uid) }
                        .ifEmpty { null }
                        .also { refreshChoicesWith = it }
                }
@ -127,7 +127,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M

            _currentPlaylistToExport.value =
                _currentPlaylistToExport.value?.let { playlist ->
-                    musicRepository.library?.findPlaylist(playlist.uid)
+                    musicRepository.userLibrary?.findPlaylist(playlist.uid)
                }
            L.d("Updated playlist to export to ${_currentPlaylistToExport.value}")
        }
@ -153,14 +153,14 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
        reason: PlaylistDecision.New.Reason
    ) {
        L.d("Opening ${songUids.size} songs to create a playlist from")
-        val library = musicRepository.library ?: return
+        val userLibrary = musicRepository.userLibrary ?: return
        val songs =
-            musicRepository.library
+            musicRepository.deviceLibrary
                ?.let { songUids.mapNotNull(it::findSong) }
                ?.also(::refreshPlaylistChoices)

        val possibleName =
-            musicRepository.library?.let {
+            musicRepository.userLibrary?.let {
                // Attempt to generate a unique default name for the playlist, like "Playlist 1".
                var i = 1
                var possibleName: String
@ -168,7 +168,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
                    possibleName = context.getString(R.string.fmt_def_playlist, i)
                    L.d("Trying $possibleName as a playlist name")
                    ++i
-                } while (library.playlists.any { it.name.resolve(context) == possibleName })
+                } while (userLibrary.playlists.any { it.name.resolve(context) == possibleName })
                L.d("$possibleName is unique, using it as the playlist name")
                possibleName
            }
@ -194,8 +194,9 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
        reason: PlaylistDecision.Rename.Reason
    ) {
        L.d("Opening playlist $playlistUid to rename")
-        val playlist = musicRepository.library?.findPlaylist(playlistUid)
-        val applySongs = musicRepository.library?.let { applySongUids.mapNotNull(it::findSong) }
+        val playlist = musicRepository.userLibrary?.findPlaylist(playlistUid)
+        val applySongs =
+            musicRepository.deviceLibrary?.let { applySongUids.mapNotNull(it::findSong) }

        _currentPendingRenamePlaylist.value =
            if (playlist != null && applySongs != null) {
@ -215,7 +216,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
        L.d("Opening playlist $playlistUid to export")
        // TODO: Add this guard to the rest of the methods here
        if (_currentPlaylistToExport.value?.uid == playlistUid) return
-        _currentPlaylistToExport.value = musicRepository.library?.findPlaylist(playlistUid)
+        _currentPlaylistToExport.value = musicRepository.userLibrary?.findPlaylist(playlistUid)
        if (_currentPlaylistToExport.value == null) {
            L.w("Given playlist UID to export was invalid")
        } else {
@ -240,7 +241,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
     */
    fun setPlaylistToDelete(playlistUid: Music.UID) {
        L.d("Opening playlist $playlistUid to delete")
-        _currentPlaylistToDelete.value = musicRepository.library?.findPlaylist(playlistUid)
+        _currentPlaylistToDelete.value = musicRepository.userLibrary?.findPlaylist(playlistUid)
        if (_currentPlaylistToDelete.value == null) {
            L.w("Given playlist UID to delete was invalid")
        }
@ -265,8 +266,8 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
                }
                else -> {
                    val trimmed = name.trim()
-                    val library = musicRepository.library
-                    if (library != null && library.findPlaylistByName(trimmed) == null) {
+                    val userLibrary = musicRepository.userLibrary
+                    if (userLibrary != null && userLibrary.findPlaylist(trimmed) == null) {
                        L.d("Chosen name is valid")
                        ChosenName.Valid(trimmed)
                    } else {
@ -285,7 +286,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
    fun setSongsToAdd(songUids: Array<Music.UID>) {
        L.d("Opening ${songUids.size} songs to add to a playlist")
        _currentSongsToAdd.value =
-            musicRepository.library
+            musicRepository.deviceLibrary
                ?.let { songUids.mapNotNull(it::findSong).ifEmpty { null } }
                ?.also(::refreshPlaylistChoices)
        if (_currentSongsToAdd.value == null || songUids.size != _currentSongsToAdd.value?.size) {
@ -294,10 +295,10 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
    }

    private fun refreshPlaylistChoices(songs: List<Song>) {
-        val library = musicRepository.library ?: return
+        val userLibrary = musicRepository.userLibrary ?: return
        L.d("Refreshing playlist choices")
        _playlistAddChoices.value =
-            Sort(Sort.Mode.ByName, Sort.Direction.ASCENDING).playlists(library.playlists).map {
+            Sort(Sort.Mode.ByName, Sort.Direction.ASCENDING).playlists(userLibrary.playlists).map {
                val songSet = it.songs.toSet()
                PlaylistChoice(it, songs.all(songSet::contains))
            }
@ -354,4 +355,4 @@ sealed interface ChosenName {
 *   [Playlist].
 * @author Alexander Capehart (OxygenCobalt)
 */
-data class PlaylistChoice(val playlist: Playlist, val alreadyAdded: Boolean)
+data class PlaylistChoice(val playlist: Playlist, val alreadyAdded: Boolean) : Item
--- a/app/src/main/java/org/oxycblt/auxio/music/decision/RenamePlaylistDialog.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/decision/RenamePlaylistDialog.kt
@ -30,7 +30,6 @@ import dagger.hilt.android.AndroidEntryPoint
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.DialogPlaylistNameBinding
 import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.music.resolve
 import org.oxycblt.auxio.ui.ViewBindingMaterialDialogFragment
 import org.oxycblt.auxio.util.collectImmediately
 import org.oxycblt.auxio.util.unlikelyToBeNull
--- a/app/src/main/java/org/oxycblt/auxio/music/device/ArtistTree.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/device/ArtistTree.kt
@ -0,0 +1,42 @@
+package org.oxycblt.auxio.music.device
+
+
+interface AlbumTree {
+    fun register(linkedSong: ArtistTree.LinkedSong): LinkedSong
+    fun resolve(): Collection<AlbumImpl>
+
+    data class LinkedSong(
+        val linkedArtistSong: ArtistTree.LinkedSong,
+        val album: Linked<AlbumImpl, SongImpl>
+    )
+}
+
+interface ArtistTree {
+    fun register(preSong: GenreTree.LinkedSong): LinkedSong
+    fun resolve(): Collection<ArtistImpl>
+
+    data class LinkedSong(
+        val linkedGenreSong: GenreTree.LinkedSong,
+        val linkedAlbum: LinkedAlbum,
+        val artists: Linked<List<ArtistImpl>,  SongImpl>
+    )
+
+    data class LinkedAlbum(
+        val preAlbum: PreAlbum,
+        val artists: Linked<List<ArtistImpl>, AlbumImpl>
+    )
+}
+
+interface GenreTree {
+    fun register(preSong: PreSong): LinkedSong
+    fun resolve(): Collection<GenreImpl>
+
+    data class LinkedSong(
+        val preSong: PreSong,
+        val genres: Linked<List<GenreImpl>, SongImpl>
+    )
+}
+
+interface Linked<P, C> {
+    fun resolve(child: C): P
+}
--- a/app/src/main/java/org/oxycblt/auxio/music/device/DeviceLibrary.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/device/DeviceLibrary.kt
@ -0,0 +1,399 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * DeviceLibrary.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.music.device
+
+import android.content.Context
+import android.net.Uri
+import android.provider.OpenableColumns
+import java.util.UUID
+import javax.inject.Inject
+import kotlinx.coroutines.channels.Channel
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicParent
+import org.oxycblt.auxio.music.MusicRepository
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.fs.Path
+import org.oxycblt.auxio.music.fs.contentResolverSafe
+import org.oxycblt.auxio.music.fs.useQuery
+import org.oxycblt.auxio.music.info.Name
+import org.oxycblt.auxio.music.metadata.Separators
+import org.oxycblt.auxio.util.forEachWithTimeout
+import org.oxycblt.auxio.util.sendWithTimeout
+import org.oxycblt.auxio.util.unlikelyToBeNull
+import timber.log.Timber as L
+
+/**
+ * Organized music library information obtained from device storage.
+ *
+ * This class allows for the creation of a well-formed music library graph from raw song
+ * information. Instances are immutable. It's generally not expected to create this yourself and
+ * instead use [MusicRepository].
+ *
+ * @author Alexander Capehart
+ */
+interface DeviceLibrary {
+    /** All [Song]s in this [DeviceLibrary]. */
+    val songs: Collection<Song>
+
+    /** All [Album]s in this [DeviceLibrary]. */
+    val albums: Collection<Album>
+
+    /** All [Artist]s in this [DeviceLibrary]. */
+    val artists: Collection<Artist>
+
+    /** All [Genre]s in this [DeviceLibrary]. */
+    val genres: Collection<Genre>
+
+    /**
+     * Find a [Song] instance corresponding to the given [Music.UID].
+     *
+     * @param uid The [Music.UID] to search for.
+     * @return The corresponding [Song], or null if one was not found.
+     */
+    fun findSong(uid: Music.UID): Song?
+
+    /**
+     * Find a [Song] instance corresponding to the given Intent.ACTION_VIEW [Uri].
+     *
+     * @param context [Context] required to analyze the [Uri].
+     * @param uri [Uri] to search for.
+     * @return A [Song] corresponding to the given [Uri], or null if one could not be found.
+     */
+    fun findSongForUri(context: Context, uri: Uri): Song?
+
+    /**
+     * Find a [Song] instance corresponding to the given [Path].
+     *
+     * @param path [Path] to search for.
+     * @return A [Song] corresponding to the given [Path], or null if one could not be found.
+     */
+    fun findSongByPath(path: Path): Song?
+
+    /**
+     * Find a [Album] instance corresponding to the given [Music.UID].
+     *
+     * @param uid The [Music.UID] to search for.
+     * @return The corresponding [Album], or null if one was not found.
+     */
+    fun findAlbum(uid: Music.UID): Album?
+
+    /**
+     * Find a [Artist] instance corresponding to the given [Music.UID].
+     *
+     * @param uid The [Music.UID] to search for.
+     * @return The corresponding [Artist], or null if one was not found.
+     */
+    fun findArtist(uid: Music.UID): Artist?
+
+    /**
+     * Find a [Genre] instance corresponding to the given [Music.UID].
+     *
+     * @param uid The [Music.UID] to search for.
+     * @return The corresponding [Genre], or null if one was not found.
+     */
+    fun findGenre(uid: Music.UID): Genre?
+
+    /** Constructs a [DeviceLibrary] implementation in an asynchronous manner. */
+    interface Factory {
+        /**
+         * Creates a new [DeviceLibrary] instance asynchronously based on the incoming stream of
+         * [RawSong] instances.
+         *
+         * @param rawSongs A stream of [RawSong] instances to process.
+         * @param processedSongs A stream of [RawSong] instances that will have been processed by
+         *   the instance.
+         */
+        suspend fun create(
+            rawSongs: Channel<RawSong>,
+            processedSongs: Channel<RawSong>,
+            separators: Separators,
+            nameFactory: Name.Known.Factory
+        ): DeviceLibrary
+    }
+}
+
+class DeviceLibraryFactoryImpl2 @Inject constructor(
+    val interpreterFactory: Interpreter.Factory
+) : DeviceLibrary.Factory {
+    override suspend fun create(
+        rawSongs: Channel<RawSong>,
+        processedSongs: Channel<RawSong>,
+        separators: Separators,
+        nameFactory: Name.Known.Factory
+    ): DeviceLibrary {
+        val interpreter = interpreterFactory.create(nameFactory, separators)
+        rawSongs.forEachWithTimeout { rawSong ->
+            interpreter.consume(rawSong)
+            processedSongs.sendWithTimeout(rawSong)
+        }
+        return interpreter.resolve()
+    }
+}
+
+class DeviceLibraryFactoryImpl @Inject constructor() : DeviceLibrary.Factory {
+    override suspend fun create(
+        rawSongs: Channel<RawSong>,
+        processedSongs: Channel<RawSong>,
+        separators: Separators,
+        nameFactory: Name.Known.Factory
+    ): DeviceLibrary {
+        val songGrouping = mutableMapOf<Music.UID, SongImpl>()
+        val albumGrouping = mutableMapOf<String?, MutableMap<UUID?, Grouping<RawAlbum, SongImpl>>>()
+        val artistGrouping = mutableMapOf<String?, MutableMap<UUID?, Grouping<RawArtist, Music>>>()
+        val genreGrouping = mutableMapOf<String?, Grouping<RawGenre, SongImpl>>()
+
+        // All music information is grouped as it is indexed by other components.
+        rawSongs.forEachWithTimeout { rawSong ->
+            val song = SongImpl(rawSong, nameFactory, separators)
+            // At times the indexer produces duplicate songs, try to filter these. Comparing by
+            // UID is sufficient for something like this, and also prevents collisions from
+            // causing severe issues elsewhere.
+            if (songGrouping.containsKey(song.uid)) {
+                L.w(
+                    "Duplicate song found: ${song.path} " +
+                        "collides with ${unlikelyToBeNull(songGrouping[song.uid]).path}")
+                // We still want to say that we "processed" the song so that the user doesn't
+                // get confused at why the bar was only partly filled by the end of the loading
+                // process.
+                processedSongs.sendWithTimeout(rawSong)
+                return@forEachWithTimeout
+            }
+            songGrouping[song.uid] = song
+
+            // Group the new song into an album.
+            appendToMusicBrainzIdTree(song, song.rawAlbum, albumGrouping) { old, new ->
+                compareSongTracks(old, new)
+            }
+            // Group the song into each of it's artists.
+            for (rawArtist in song.rawArtists) {
+                appendToMusicBrainzIdTree(song, rawArtist, artistGrouping) { old, new ->
+                    // Artist information from earlier dates is prioritized, as it is less likely to
+                    // change with the addition of new tracks. Fall back to the name otherwise.
+                    check(old is SongImpl) // This should always be the case.
+                    compareSongDates(old, new)
+                }
+            }
+
+            // Group the song into each of it's genres.
+            for (rawGenre in song.rawGenres) {
+                appendToNameTree(song, rawGenre, genreGrouping) { old, new -> new.name < old.name }
+            }
+
+            processedSongs.sendWithTimeout(rawSong)
+        }
+
+        // Now that all songs are processed, also process albums and group them into their
+        // respective artists.
+        pruneMusicBrainzIdTree(albumGrouping) { old, new -> compareSongTracks(old, new) }
+        val albums = flattenMusicBrainzIdTree(albumGrouping) { AlbumImpl(it, nameFactory) }
+        for (album in albums) {
+            for (rawArtist in album.rawArtists) {
+                appendToMusicBrainzIdTree(album, rawArtist, artistGrouping) { old, new ->
+                    when (old) {
+                        // Immediately replace any songs that initially held the priority position.
+                        is SongImpl -> true
+                        is AlbumImpl -> {
+                            compareAlbumDates(old, new)
+                        }
+                        else -> throw IllegalStateException()
+                    }
+                }
+            }
+        }
+
+        // Artists and genres do not need to be grouped and can be processed immediately.
+        pruneMusicBrainzIdTree(artistGrouping) { old, new ->
+            when {
+                // Immediately replace any songs that initially held the priority position.
+                old is SongImpl && new is AlbumImpl -> true
+                old is AlbumImpl && new is SongImpl -> false
+                old is SongImpl && new is SongImpl -> {
+                    compareSongDates(old, new)
+                }
+                old is AlbumImpl && new is AlbumImpl -> {
+                    compareAlbumDates(old, new)
+                }
+                else -> throw IllegalStateException()
+            }
+        }
+        val artists = flattenMusicBrainzIdTree(artistGrouping) { ArtistImpl(it, nameFactory) }
+        val genres = flattenNameTree(genreGrouping) { GenreImpl(it, nameFactory) }
+
+        return DeviceLibraryImpl(songGrouping.values.toSet(), albums, artists, genres)
+    }
+
+    private inline fun <R : NameGroupable, O : Music, N : O> appendToNameTree(
+        music: N,
+        raw: R,
+        tree: MutableMap<String?, Grouping<R, O>>,
+        prioritize: (old: O, new: N) -> Boolean,
+    ) {
+        val nameKey = raw.name?.lowercase()
+        val body = tree[nameKey]
+        if (body != null) {
+            body.music.add(music)
+            if (prioritize(body.raw.src, music)) {
+                body.raw = PrioritizedRaw(raw, music)
+            }
+        } else {
+            // Need to initialize this grouping.
+            tree[nameKey] = Grouping(PrioritizedRaw(raw, music), mutableSetOf(music))
+        }
+    }
+
+    private inline fun <R : NameGroupable, O : Music, P : MusicParent> flattenNameTree(
+        tree: MutableMap<String?, Grouping<R, O>>,
+        map: (Grouping<R, O>) -> P
+    ): Set<P> = tree.values.mapTo(mutableSetOf()) { map(it) }
+
+    private inline fun <R : MusicBrainzGroupable, O : Music, N : O> appendToMusicBrainzIdTree(
+        music: N,
+        raw: R,
+        tree: MutableMap<String?, MutableMap<UUID?, Grouping<R, O>>>,
+        prioritize: (old: O, new: N) -> Boolean,
+    ) {
+        val nameKey = raw.name?.lowercase()
+        val musicBrainzIdGroups = tree[nameKey]
+        if (musicBrainzIdGroups != null) {
+            val body = musicBrainzIdGroups[raw.musicBrainzId]
+            if (body != null) {
+                body.music.add(music)
+                if (prioritize(body.raw.src, music)) {
+                    body.raw = PrioritizedRaw(raw, music)
+                }
+            } else {
+                // Need to initialize this grouping.
+                musicBrainzIdGroups[raw.musicBrainzId] =
+                    Grouping(PrioritizedRaw(raw, music), mutableSetOf(music))
+            }
+        } else {
+            // Need to initialize this grouping.
+            tree[nameKey] =
+                mutableMapOf(
+                    raw.musicBrainzId to Grouping(PrioritizedRaw(raw, music), mutableSetOf(music)))
+        }
+    }
+
+    private inline fun <R, M : Music> pruneMusicBrainzIdTree(
+        tree: MutableMap<String?, MutableMap<UUID?, Grouping<R, M>>>,
+        prioritize: (old: M, new: M) -> Boolean
+    ) {
+        for ((_, musicBrainzIdGroups) in tree) {
+            var nullGroup = musicBrainzIdGroups[null]
+            if (nullGroup == null) {
+                // Full MusicBrainz ID tagging. Nothing to do.
+                continue
+            }
+            // Only partial MusicBrainz ID tagging. For the sake of basic sanity, just
+            // collapse all of them into the null group.
+            // TODO: More advanced heuristics eventually (tm)
+            musicBrainzIdGroups
+                .filter { it.key != null }
+                .forEach {
+                    val (_, group) = it
+                    nullGroup.music.addAll(group.music)
+                    if (prioritize(group.raw.src, nullGroup.raw.src)) {
+                        nullGroup.raw = group.raw
+                    }
+                    musicBrainzIdGroups.remove(it.key)
+                }
+        }
+    }
+
+    private inline fun <R, M : Music, T : MusicParent> flattenMusicBrainzIdTree(
+        tree: MutableMap<String?, MutableMap<UUID?, Grouping<R, M>>>,
+        map: (Grouping<R, M>) -> T
+    ): Set<T> {
+        val result = mutableSetOf<T>()
+        for ((_, musicBrainzIdGroups) in tree) {
+            for (group in musicBrainzIdGroups.values) {
+                result += map(group)
+            }
+        }
+        return result
+    }
+
+    private fun compareSongTracks(old: SongImpl, new: SongImpl) =
+        new.track != null &&
+            (old.track == null ||
+                new.track < old.track ||
+                (new.track == old.track && new.name < old.name))
+
+    private fun compareAlbumDates(old: AlbumImpl, new: AlbumImpl) =
+        new.dates != null &&
+            (old.dates == null ||
+                new.dates < old.dates ||
+                (new.dates == old.dates && new.name < old.name))
+
+    private fun compareSongDates(old: SongImpl, new: SongImpl) =
+        new.date != null &&
+            (old.date == null ||
+                new.date < old.date ||
+                (new.date == old.date && new.name < old.name))
+}
+
+// TODO: Avoid redundant data creation
+
+class DeviceLibraryImpl(
+    override val songs: Collection<SongImpl>,
+    override val albums: Collection<AlbumImpl>,
+    override val artists: Collection<ArtistImpl>,
+    override val genres: Collection<GenreImpl>
+) : DeviceLibrary {
+    // Use a mapping to make finding information based on it's UID much faster.
+    private val songUidMap = buildMap { songs.forEach { put(it.uid, it.finalize()) } }
+    private val songPathMap = buildMap { songs.forEach { put(it.path, it) } }
+    private val albumUidMap = buildMap { albums.forEach { put(it.uid, it.finalize()) } }
+    private val artistUidMap = buildMap { artists.forEach { put(it.uid, it.finalize()) } }
+    private val genreUidMap = buildMap { genres.forEach { put(it.uid, it.finalize()) } }
+
+    // All other music is built from songs, so comparison only needs to check songs.
+    override fun equals(other: Any?) = other is DeviceLibrary && other.songs == songs
+
+    override fun hashCode() = songs.hashCode()
+
+    override fun toString() =
+        "DeviceLibrary(songs=${songs.size}, albums=${albums.size}, " +
+            "artists=${artists.size}, genres=${genres.size})"
+
+    override fun findSong(uid: Music.UID): Song? = songUidMap[uid]
+
+    override fun findAlbum(uid: Music.UID): Album? = albumUidMap[uid]
+
+    override fun findArtist(uid: Music.UID): Artist? = artistUidMap[uid]
+
+    override fun findGenre(uid: Music.UID): Genre? = genreUidMap[uid]
+
+    override fun findSongByPath(path: Path) = songPathMap[path]
+
+    override fun findSongForUri(context: Context, uri: Uri) =
+        context.contentResolverSafe.useQuery(
+            uri, arrayOf(OpenableColumns.DISPLAY_NAME, OpenableColumns.SIZE)) { cursor ->
+                cursor.moveToFirst()
+                // We are weirdly limited to DISPLAY_NAME and SIZE when trying to locate a
+                // song. Do what we can to hopefully find the song the user wanted to open.
+                val displayName =
+                    cursor.getString(cursor.getColumnIndexOrThrow(OpenableColumns.DISPLAY_NAME))
+                val size = cursor.getLong(cursor.getColumnIndexOrThrow(OpenableColumns.SIZE))
+                songs.find { it.path.name == displayName && it.size == size }
+            }
+}
--- a/app/src/main/java/org/oxycblt/auxio/music/device/DeviceModule.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/device/DeviceModule.kt
@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2025 Auxio Project
- * JClassRef.cpp is part of Auxio.
+ * Copyright (c) 2023 Auxio Project
+ * DeviceModule.kt is part of Auxio.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
@ -16,19 +16,16 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-#include "JClassRef.h"
-JClassRef::JClassRef(JNIEnv *env, const char *classpath) : env(env) {
-    clazz = env->FindClass(classpath);
-}
+package org.oxycblt.auxio.music.device

-JClassRef::~JClassRef() {
-    env->DeleteLocalRef(clazz);
-}
+import dagger.Binds
+import dagger.Module
+import dagger.hilt.InstallIn
+import dagger.hilt.components.SingletonComponent

-jmethodID JClassRef::method(const char *name, const char *signature) {
-    return env->GetMethodID(clazz, name, signature);
-}
-
-jclass& JClassRef::operator*() {
-    return clazz;
+@Module
+@InstallIn(SingletonComponent::class)
+interface DeviceModule {
+    @Binds fun deviceLibraryFactory(factory: DeviceLibraryFactoryImpl2): DeviceLibrary.Factory
+    @Binds fun interpreterFactory(factory: InterpreterFactoryImpl): Interpreter.Factory
 }
--- a/app/src/main/java/org/oxycblt/auxio/music/device/DeviceMusicImpl.kt
+++ b/app/src/main/java/org/oxycblt/auxio/music/device/DeviceMusicImpl.kt
@ -0,0 +1,335 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * DeviceMusicImpl.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.oxycblt.auxio.music.device
+
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.image.extractor.ParentCover
+import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
+import org.oxycblt.auxio.music.MusicType
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.info.Date
+import org.oxycblt.auxio.music.info.Name
+import org.oxycblt.auxio.util.positiveOrNull
+import org.oxycblt.auxio.util.update
+import kotlin.math.min
+
+/**
+ * Library-backed implementation of [Song].
+ *
+ * @param linkedSong The completed [LinkedSong] all metadata van be inferred from
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class SongImpl(linkedSong: LinkedSong) : Song {
+    private val preSong = linkedSong.preSong
+
+    override val uid =
+        // Attempt to use a MusicBrainz ID first before falling back to a hashed UID.
+        preSong.musicBrainzId?.let { Music.UID.musicBrainz(MusicType.SONGS, it) }
+            ?: Music.UID.auxio(MusicType.SONGS) {
+                // Song UIDs are based on the raw data without parsing so that they remain
+                // consistent across music setting changes. Parents are not held up to the
+                // same standard since grouping is already inherently linked to settings.
+                update(preSong.rawName)
+                update(preSong.preAlbum.rawName)
+                update(preSong.date)
+
+                update(preSong.track)
+                update(preSong.disc?.number)
+
+                update(preSong.preArtists.map { it.rawName })
+                update(preSong.preAlbum.preArtists.map { it.rawName })
+            }
+    override val name = preSong.name
+    override val track = preSong.track
+    override val disc = preSong.disc
+    override val date = preSong.date
+    override val uri = preSong.uri
+    override val cover = preSong.cover
+    override val path = preSong.path
+    override val mimeType = preSong.mimeType
+    override val size = preSong.size
+    override val durationMs = preSong.durationMs
+    override val replayGainAdjustment = preSong.replayGainAdjustment
+    override val dateAdded = preSong.dateAdded
+    override val album = linkedSong.album.resolve(this)
+    override val artists = linkedSong.artists.resolve(this)
+    override val genres = linkedSong.genres.resolve(this)
+
+    private val hashCode = 31 * uid.hashCode() + preSong.hashCode()
+
+    override fun hashCode() = hashCode
+
+    override fun equals(other: Any?) =
+        other is SongImpl &&
+                uid == other.uid &&
+                preSong == other.preSong
+
+    override fun toString() = "Song(uid=$uid, name=$name)"
+}
+
+/**
+ * Library-backed implementation of [Album].
+ *
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class AlbumImpl(linkedAlbum: LinkedAlbum) : Album {
+    private val preAlbum = linkedAlbum.preAlbum
+
+    override val uid =
+        // Attempt to use a MusicBrainz ID first before falling back to a hashed UID.
+        preAlbum.musicBrainzId?.let { Music.UID.musicBrainz(MusicType.ALBUMS, it) }
+            ?: Music.UID.auxio(MusicType.ALBUMS) {
+                // Hash based on only names despite the presence of a date to increase stability.
+                // I don't know if there is any situation where an artist will have two albums with
+                // the exact same name, but if there is, I would love to know.
+                update(preAlbum.rawName)
+                update(preAlbum.preArtists.map { it.rawName })
+            }
+    override val name = preAlbum.name
+    override val releaseType = preAlbum.releaseType
+    override var durationMs = 0L
+    override var dateAdded = 0L
+    override lateinit var cover: ParentCover
+    override var dates: Date.Range? = null
+
+    override val artists = linkedAlbum.artists.resolve(this)
+    override val songs = mutableSetOf<Song>()
+
+    private var hashCode = 31 * uid.hashCode() + preAlbum.hashCode()
+
+    override fun hashCode() = hashCode
+
+    // Since equality on public-facing music models is not identical to the tag equality,
+    // we just compare raw instances and how they are interpreted.
+    override fun equals(other: Any?) =
+        other is AlbumImpl &&
+                uid == other.uid &&
+                preAlbum == other.preAlbum &&
+                songs == other.songs
+
+    override fun toString() = "Album(uid=$uid, name=$name)"
+
+    fun link(song: SongImpl) {
+        songs.add(song)
+        hashCode = 31 * hashCode + song.hashCode()
+        durationMs += song.durationMs
+        dateAdded = min(dateAdded, song.dateAdded)
+        if (song.date != null) {
+            dates = dates?.let {
+                if (song.date < it.min) Date.Range(song.date, it.max)
+                else if (song.date > it.max) Date.Range(it.min, song.date)
+                else it
+            } ?: Date.Range(song.date, song.date)
+        }
+    }
+
+    /**
+     * Perform final validation and organization on this instance.
+     *
+     * @return This instance upcasted to [Album].
+     */
+    fun finalize(): Album {
+        return this
+    }
+}
+
+/**
+ * Library-backed implementation of [Artist].
+ *
+ * @param grouping [Grouping] to derive the member data from.
+ * @param nameFactory The [Name.Known.Factory] to interpret name information with.
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class ArtistImpl(
+    grouping: Grouping<RawArtist, Music>,
+    private val nameFactory: Name.Known.Factory
+) : Artist {
+    private val rawArtist = grouping.raw.inner
+
+    override val uid =
+        // Attempt to use a MusicBrainz ID first before falling back to a hashed UID.
+        rawArtist.musicBrainzId?.let { Music.UID.musicBrainz(MusicType.ARTISTS, it) }
+            ?: Music.UID.auxio(MusicType.ARTISTS) { update(rawArtist.name) }
+    override val name =
+        rawArtist.name?.let { nameFactory.parse(it, rawArtist.sortName) }
+            ?: Name.Unknown(R.string.def_artist)
+
+    override val songs: Set<Song>
+    override val explicitAlbums: Set<Album>
+    override val implicitAlbums: Set<Album>
+    override val durationMs: Long?
+    override val cover: ParentCover
+
+    override lateinit var genres: List<Genre>
+
+    private var hashCode = uid.hashCode()
+
+    init {
+        val distinctSongs = mutableSetOf<Song>()
+        val albumMap = mutableMapOf<Album, Boolean>()
+
+        for (music in grouping.music) {
+            when (music) {
+                is SongImpl -> {
+                    music.link(this)
+                    distinctSongs.add(music)
+                    if (albumMap[music.album] == null) {
+                        albumMap[music.album] = false
+                    }
+                }
+
+                is AlbumImpl -> {
+                    music.link(this)
+                    albumMap[music] = true
+                }
+
+                else -> error("Unexpected input music $music in $name ${music::class.simpleName}")
+            }
+        }
+
+        songs = distinctSongs
+        val albums = albumMap.keys
+        explicitAlbums = albums.filterTo(mutableSetOf()) { albumMap[it] == true }
+        implicitAlbums = albums.filterNotTo(mutableSetOf()) { albumMap[it] == true }
+        durationMs = songs.sumOf { it.durationMs }.positiveOrNull()
+
+        val singleCover =
+            when (val src = grouping.raw.src) {
+                is SongImpl -> src.cover
+                is AlbumImpl -> src.cover.single
+                else -> error("Unexpected input source $src in $name ${src::class.simpleName}")
+            }
+        cover = ParentCover.from(singleCover, songs)
+
+        hashCode = 31 * hashCode + rawArtist.hashCode()
+        hashCode = 31 * hashCode + nameFactory.hashCode()
+        hashCode = 31 * hashCode + songs.hashCode()
+    }
+
+    // Note: Append song contents to MusicParent equality so that artists with
+    // the same UID but different songs are not equal.
+    override fun hashCode() = hashCode
+
+    // Since equality on public-facing music models is not identical to the tag equality,
+    // we just compare raw instances and how they are interpreted.
+    override fun equals(other: Any?) =
+        other is ArtistImpl &&
+                uid == other.uid &&
+                rawArtist == other.rawArtist &&
+                nameFactory == other.nameFactory &&
+                songs == other.songs
+
+    override fun toString() = "Artist(uid=$uid, name=$name)"
+
+
+    /**
+     * Perform final validation and organization on this instance.
+     *
+     * @return This instance upcasted to [Artist].
+     */
+    fun finalize(): Artist {
+        // There are valid artist configurations:
+        // 1. No songs, no implicit albums, some explicit albums
+        // 2. Some songs, no implicit albums, some explicit albums
+        // 3. Some songs, some implicit albums, no implicit albums
+        // 4. Some songs, some implicit albums, some explicit albums
+        // I'm pretty sure the latter check could be reduced to just explicitAlbums.isNotEmpty,
+        // but I can't be 100% certain.
+        check(songs.isNotEmpty() || (implicitAlbums.size + explicitAlbums.size) > 0) {
+            "Malformed artist $name: Empty"
+        }
+        genres =
+            Sort(Sort.Mode.ByName, Sort.Direction.ASCENDING)
+                .genres(songs.flatMapTo(mutableSetOf()) { it.genres })
+                .sortedByDescending { genre -> songs.count { it.genres.contains(genre) } }
+        return this
+    }
+}
+
+/**
+ * Library-backed implementation of [Genre].
+ *
+ * @param grouping [Grouping] to derive the member data from.
+ * @param nameFactory The [Name.Known.Factory] to interpret name information with.
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+class GenreImpl(
+    grouping: Grouping<RawGenre, SongImpl>,
+    private val nameFactory: Name.Known.Factory
+) : Genre {
+    private val rawGenre = grouping.raw.inner
+
+    override val uid = Music.UID.auxio(MusicType.GENRES) { update(rawGenre.name) }
+    override val name =
+        rawGenre.name?.let { nameFactory.parse(it, rawGenre.name) }
+            ?: Name.Unknown(R.string.def_genre)
+
+    override val songs: Set<Song>
+    override val artists: Set<Artist>
+    override val durationMs: Long
+    override val cover: ParentCover
+
+    private var hashCode = uid.hashCode()
+
+    init {
+        val distinctArtists = mutableSetOf<Artist>()
+        var totalDuration = 0L
+
+        for (song in grouping.music) {
+            song.link(this)
+            distinctArtists.addAll(song.artists)
+            totalDuration += song.durationMs
+        }
+
+        songs = grouping.music
+        artists = distinctArtists
+        durationMs = totalDuration
+
+        cover = ParentCover.from(grouping.raw.src.cover, songs)
+
+        hashCode = 31 * hashCode + rawGenre.hashCode()
+        hashCode = 31 * hashCode + nameFactory.hashCode()
+        hashCode = 31 * hashCode + songs.hashCode()
+    }
+
+    override fun hashCode() = hashCode
+
+    override fun equals(other: Any?) =
+        other is GenreImpl &&
+                uid == other.uid &&
+                rawGenre == other.rawGenre &&
+                nameFactory == other.nameFactory &&
+                songs == other.songs
+
+    override fun toString() = "Genre(uid=$uid, name=$name)"
+
+    /**
+     * Perform final validation and organization on this instance.
+     *
+     * @return This instance upcasted to [Genre].
+     */
+    fun finalize(): Genre {
+        check(songs.isNotEmpty()) { "Malformed genre $name: Empty" }
+        return this
+    }
+}
--- a/Show more
+++ b/Show more