playback: add framework for handling pre-amp

Implement an internal setting for a ReplayGain pre-amp setting.

Pre-amp is a lot like above reference volume regarding Auxio's
ReplayGain implementation, where I want to implement it in order
to allow ReplayGain to graduate from being labeled "experimental".

No UI frontend has been implemented just yet.

app/src/main/java/org/oxycblt/auxio/home/HomeViewModel.kt

@@ -145,7 +145,7 @@ class HomeViewModel : ViewModel(), SettingsManager.Callback, MusicStore.Callback
         }
     }
 
-    override fun onLibTabsUpdate(libTabs: Array<Tab>) {
+    override fun onLibraryChanged() {
         tabs = visibleTabs
         _shouldRecreateTabs.value = true
     }

app/src/main/java/org/oxycblt/auxio/playback/replaygain/ReplayGainAudioProcessor.kt

@@ -15,7 +15,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
  
-package org.oxycblt.auxio.playback.system
+package org.oxycblt.auxio.playback.replaygain
 
 import com.google.android.exoplayer2.C
 import com.google.android.exoplayer2.audio.AudioProcessor
@@ -23,6 +23,7 @@ import com.google.android.exoplayer2.audio.BaseAudioProcessor
 import com.google.android.exoplayer2.metadata.Metadata
 import com.google.android.exoplayer2.metadata.id3.TextInformationFrame
 import com.google.android.exoplayer2.metadata.vorbis.VorbisComment
+import java.lang.UnsupportedOperationException
 import java.nio.ByteBuffer
 import kotlin.math.pow
 import org.oxycblt.auxio.music.Album
@@ -39,8 +40,6 @@ import org.oxycblt.auxio.util.unlikelyToBeNull
  * manipulates the bitstream itself to modify the volume, which allows the use of positive
  * ReplayGain values.
  *
- * TODO: Pre-amp values
- *
  * @author OxygenCobalt
  */
 class ReplayGainAudioProcessor : BaseAudioProcessor() {
@@ -64,23 +63,21 @@ class ReplayGainAudioProcessor : BaseAudioProcessor() {
      * Vanilla Music's implementation.
      */
     fun applyReplayGain(metadata: Metadata?) {
-        if (metadata == null || settingsManager.replayGainMode == ReplayGainMode.OFF) {
+        if (settingsManager.replayGainMode == ReplayGainMode.OFF) {
-            logW(
+            logW("ReplayGain not enabled")
-                "Not applying replaygain [" +
-                    "metadata: ${metadata != null}, " +
-                    "enabled: ${settingsManager.replayGainMode == ReplayGainMode.OFF}]")
             volume = 1f
             return
         }
 
-        val gain = parseReplayGain(metadata)
+        val gain = metadata?.let(::parseReplayGain)
+        val preAmp = settingsManager.replayGainPreAmp
 
         val adjust =
             if (gain != null) {
                 // ReplayGain is configurable, so determine what to do based off of the mode.
                 val useAlbumGain =
                     when (settingsManager.replayGainMode) {
-                        ReplayGainMode.OFF -> error("Unreachable")
+                        ReplayGainMode.OFF -> throw UnsupportedOperationException()
 
                         // User wants track gain to be preferred. Default to album gain only if
                         // there is no track gain.
@@ -96,18 +93,25 @@ class ReplayGainAudioProcessor : BaseAudioProcessor() {
                                 playbackManager.song?.album?.id == playbackManager.parent?.id
                     }
 
-                if (useAlbumGain) {
+                val resolvedGain =
-                    logD("Using album gain")
+                    if (useAlbumGain) {
-                    gain.album
+                        logD("Using album gain")
-                } else {
+                        gain.album
-                    logD("Using track gain")
+                    } else {
-                    gain.track
+                        logD("Using track gain")
-                }
+                        gain.track
+                    }
+
+                // Apply the "With tags" adjustment
+                resolvedGain + preAmp.with
             } else {
-                // No gain tags were present
+                // No gain tags were present, just apply the adjustment without tags.
-                0f
+                logD("No ReplayGain tags present ")
+                preAmp.without
             }
 
+        logD("Applying ReplayGain adjustment ${adjust}db")
+
         // Final adjustment along the volume curve.
         volume = 10f.pow(adjust / 20f)
     }

app/src/main/java/org/oxycblt/auxio/playback/replaygain/ReplayGainModels.kt

@@ -15,7 +15,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
  
-package org.oxycblt.auxio.playback.system
+package org.oxycblt.auxio.playback.replaygain
 
 import org.oxycblt.auxio.IntegerTable
 
@@ -42,3 +42,9 @@ enum class ReplayGainMode {
         }
     }
 }
+
+/** Represents the ReplayGain pre-amp */
+data class ReplayGainPreAmp(
+    val with: Float,
+    val without: Float,
+)

app/src/main/java/org/oxycblt/auxio/playback/system/MediaButtonReceiver.kt

@@ -29,7 +29,6 @@ import android.content.Intent
  * KitKat don't break! To prevent Auxio from not showing up at all in these apps, we declare a
  * BroadcastReceiver in the manifest that actually does nothing. Any broadcast by apps should be
  * routed by the media session when the service exists.
- * @author OxygenCobalt
  */
 class MediaButtonReceiver : BroadcastReceiver() {
     override fun onReceive(context: Context, intent: Intent) {}

app/src/main/java/org/oxycblt/auxio/playback/system/MediaSessionComponent.kt

@@ -52,6 +52,7 @@ class MediaSessionComponent(private val context: Context, private val player: Pl
     init {
         player.addListener(this)
         playbackManager.addCallback(this)
+        settingsManager.addCallback(this)
         mediaSession.setCallback(this)
     }
 
@@ -101,9 +102,6 @@ class MediaSessionComponent(private val context: Context, private val player: Pl
                 .putLong(MediaMetadataCompat.METADATA_KEY_TRACK_NUMBER, song.track?.toLong() ?: 0L)
                 .putText(MediaMetadataCompat.METADATA_KEY_DATE, song.album.year?.toString())
                 .putLong(MediaMetadataCompat.METADATA_KEY_DURATION, song.durationMs)
-                .putText(
-                    MediaMetadataCompat.METADATA_KEY_ALBUM_ART_URI,
-                    song.album.albumCoverUri.toString())
 
         // Normally, android expects one to provide a URI to the metadata instance instead of
         // a full blown bitmap. In practice, this is not ideal in the slightest, as we cannot
@@ -145,11 +143,7 @@ class MediaSessionComponent(private val context: Context, private val player: Pl
 
     // --- SETTINGSMANAGER CALLBACKS ---
 
-    override fun onShowCoverUpdate(showCovers: Boolean) {
+    override fun onCoverSettingsChanged() {
-        updateMediaMetadata(playbackManager.song)
-    }
-
-    override fun onQualityCoverUpdate(doQualityCovers: Boolean) {
         updateMediaMetadata(playbackManager.song)
     }
 

app/src/main/java/org/oxycblt/auxio/playback/system/NotificationComponent.kt

@@ -35,13 +35,14 @@ import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.state.RepeatMode
 import org.oxycblt.auxio.util.getSystemServiceSafe
+import org.oxycblt.auxio.util.logD
 import org.oxycblt.auxio.util.newBroadcastIntent
 import org.oxycblt.auxio.util.newMainIntent
 
 /**
  * The unified notification for [PlaybackService]. Due to the nature of how this notification is
  * used, it is *not self-sufficient*. Updates have to be delivered manually, as to prevent state
- * inconsistency when the foreground state is started.
+ * inconsistency derived from callback order.
  * @author OxygenCobalt
  */
 @SuppressLint("RestrictedApi")
@@ -108,6 +109,7 @@ class NotificationComponent(
             object : BitmapProvider.Target {
                 override fun onCompleted(bitmap: Bitmap?) {
                     setLargeIcon(bitmap)
+                    setLargeIcon(null)
                     callback.onNotificationChanged(this@NotificationComponent)
                 }
             })

app/src/main/java/org/oxycblt/auxio/playback/system/PlaybackService.kt

@@ -47,6 +47,7 @@ import org.oxycblt.auxio.BuildConfig
 import org.oxycblt.auxio.IntegerTable
 import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.playback.replaygain.ReplayGainAudioProcessor
 import org.oxycblt.auxio.playback.state.PlaybackStateManager
 import org.oxycblt.auxio.playback.state.RepeatMode
 import org.oxycblt.auxio.settings.SettingsManager
@@ -291,24 +292,18 @@ class PlaybackService :
 
     // --- SETTINGSMANAGER OVERRIDES ---
 
-    override fun onReplayGainUpdate(mode: ReplayGainMode) {
+    override fun onReplayGainSettingsChanged() {
         onTracksInfoChanged(player.currentTracksInfo)
     }
 
-    override fun onShowCoverUpdate(showCovers: Boolean) {
+    override fun onCoverSettingsChanged() {
         playbackManager.song?.let { song ->
             notificationComponent.updateMetadata(song, playbackManager.parent)
         }
     }
 
-    override fun onQualityCoverUpdate(doQualityCovers: Boolean) {
+    override fun onNotifSettingsChanged() {
-        playbackManager.song?.let { song ->
+        if (settingsManager.useAltNotifAction) {
-            notificationComponent.updateMetadata(song, playbackManager.parent)
-        }
-    }
-
-    override fun onNotifActionUpdate(useAltAction: Boolean) {
-        if (useAltAction) {
             onShuffledChanged(playbackManager.isShuffled)
         } else {
             onRepeatChanged(playbackManager.repeatMode)

app/src/main/java/org/oxycblt/auxio/settings/SettingsListFragment.kt

@@ -61,7 +61,7 @@ class SettingsListFragment : PreferenceFragmentCompat() {
         preferenceManager.onDisplayPreferenceDialogListener = this
         preferenceScreen.children.forEach(::recursivelyHandlePreference)
 
-        // Make the RecycleBiew edge-to-edge capable
+        // Make the RecycleView edge-to-edge capable
         view.findViewById<RecyclerView>(androidx.preference.R.id.recycler_view).apply {
             clipToPadding = false
 

app/src/main/java/org/oxycblt/auxio/settings/SettingsManager.kt

@@ -24,7 +24,8 @@ import androidx.core.content.edit
 import androidx.preference.PreferenceManager
 import org.oxycblt.auxio.home.tabs.Tab
 import org.oxycblt.auxio.playback.state.PlaybackMode
-import org.oxycblt.auxio.playback.system.ReplayGainMode
+import org.oxycblt.auxio.playback.replaygain.ReplayGainMode
+import org.oxycblt.auxio.playback.replaygain.ReplayGainPreAmp
 import org.oxycblt.auxio.ui.DisplayMode
 import org.oxycblt.auxio.ui.Sort
 import org.oxycblt.auxio.ui.accent.Accent
@@ -104,6 +105,20 @@ class SettingsManager private constructor(context: Context) :
             ReplayGainMode.fromIntCode(prefs.getInt(KEY_REPLAY_GAIN, Int.MIN_VALUE))
                 ?: ReplayGainMode.OFF
 
+    /** The current ReplayGain pre-amp configuration */
+    var replayGainPreAmp: ReplayGainPreAmp
+        get() =
+            ReplayGainPreAmp(
+                prefs.getFloat(KEY_REPLAY_GAIN_PRE_AMP_WITH, 0f),
+                prefs.getFloat(KEY_REPLAY_GAIN_PRE_AMP_WITHOUT, 0f))
+        set(value) {
+            prefs.edit {
+                putFloat(KEY_REPLAY_GAIN_PRE_AMP_WITH, value.with)
+                putFloat(KEY_REPLAY_GAIN_PRE_AMP_WITHOUT, value.without)
+                apply()
+            }
+        }
+
     /** What queue to create when a song is selected (ex. From All Songs or Search) */
     val songPlaybackMode: PlaybackMode
         get() =
@@ -186,6 +201,7 @@ class SettingsManager private constructor(context: Context) :
                 Sort.fromIntCode(prefs.getInt(KEY_DETAIL_ALBUM_SORT, Int.MIN_VALUE))
                     ?: Sort.ByDisc(true)
 
+            // Correct legacy album sort modes to Disc
             if (sort is Sort.ByName) {
                 sort = Sort.ByDisc(sort.isAscending)
             }
@@ -239,12 +255,11 @@ class SettingsManager private constructor(context: Context) :
 
     override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences?, key: String?) {
         when (key) {
-            KEY_USE_ALT_NOTIFICATION_ACTION ->
+            KEY_USE_ALT_NOTIFICATION_ACTION -> callbacks.forEach { it.onNotifSettingsChanged() }
-                callbacks.forEach { it.onNotifActionUpdate(useAltNotifAction) }
+            KEY_SHOW_COVERS, KEY_QUALITY_COVERS -> callbacks.forEach { it.onCoverSettingsChanged() }
-            KEY_SHOW_COVERS -> callbacks.forEach { it.onShowCoverUpdate(showCovers) }
+            KEY_LIB_TABS -> callbacks.forEach { it.onLibraryChanged() }
-            KEY_QUALITY_COVERS -> callbacks.forEach { it.onQualityCoverUpdate(useQualityCovers) }
+            KEY_REPLAY_GAIN, KEY_REPLAY_GAIN_PRE_AMP_WITH, KEY_REPLAY_GAIN_PRE_AMP_WITHOUT ->
-            KEY_LIB_TABS -> callbacks.forEach { it.onLibTabsUpdate(libTabs) }
+                callbacks.forEach { it.onReplayGainSettingsChanged() }
-            KEY_REPLAY_GAIN -> callbacks.forEach { it.onReplayGainUpdate(replayGainMode) }
         }
     }
 
@@ -254,11 +269,10 @@ class SettingsManager private constructor(context: Context) :
      * context.
      */
     interface Callback {
-        fun onLibTabsUpdate(libTabs: Array<Tab>) {}
+        fun onLibraryChanged() {}
-        fun onNotifActionUpdate(useAltAction: Boolean) {}
+        fun onNotifSettingsChanged() {}
-        fun onShowCoverUpdate(showCovers: Boolean) {}
+        fun onCoverSettingsChanged() {}
-        fun onQualityCoverUpdate(doQualityCovers: Boolean) {}
+        fun onReplayGainSettingsChanged() {}
-        fun onReplayGainUpdate(mode: ReplayGainMode) {}
     }
 
     companion object {
@@ -276,6 +290,9 @@ class SettingsManager private constructor(context: Context) :
 
         const val KEY_HEADSET_AUTOPLAY = "auxio_headset_autoplay"
         const val KEY_REPLAY_GAIN = "auxio_replay_gain"
+        const val KEY_REPLAY_GAIN_PRE_AMP = "auxio_pre_amp"
+        const val KEY_REPLAY_GAIN_PRE_AMP_WITH = "auxio_pre_amp_with"
+        const val KEY_REPLAY_GAIN_PRE_AMP_WITHOUT = "auxio_pre_amp_without"
 
         const val KEY_SONG_PLAYBACK_MODE = "KEY_SONG_PLAY_MODE2"
         const val KEY_KEEP_SHUFFLE = "KEY_KEEP_SHUFFLE"

app/src/main/java/org/oxycblt/auxio/ui/StyledImageButton.kt

@@ -35,9 +35,9 @@ import org.oxycblt.auxio.util.getDrawableSafe
  * More specifically, this class add two features:
  * - Specification of the icon size. This is to accommodate the playback buttons, which tend to be
  * larger as by default the playback icons look terrible with the gobs of whitespace everywhere.
- * - Addition of an indicator, which is a dot that can denote when a button is active. This is
+ * - Addition of an indicator, which is a dot that can denote when a button is active. This is also
- * also useful for the playback buttons, as at times highlighting them is not enough to
+ * useful for the playback buttons, as at times highlighting them is not enough to differentiate
- * differentiate them.
+ * them.
  * @author OxygenCobalt
  */
 class StyledImageButton

app/src/main/java/org/oxycblt/auxio/ui/StyledImageView.kt

@@ -45,8 +45,8 @@ import org.oxycblt.auxio.util.getDrawableSafe
  * An [AppCompatImageView] that applies many of the stylistic choices that Auxio uses regarding
  * images.
  *
- * Default behavior includes the addition of a tonal background, automatic sizing of icons to
+ * Default behavior includes the addition of a tonal background, automatic sizing of icons to half
- * half of the view size, and corner radius application depending on user preference.
+ * of the view size, and corner radius application depending on user preference.
  * @author OxygenCobalt
  */
 class StyledImageView

app/src/main/java/org/oxycblt/auxio/widgets/WidgetComponent.kt

@@ -131,8 +131,7 @@ class WidgetComponent(private val context: Context) :
     override fun onPlayingChanged(isPlaying: Boolean) = update()
     override fun onShuffledChanged(isShuffled: Boolean) = update()
     override fun onRepeatChanged(repeatMode: RepeatMode) = update()
-    override fun onShowCoverUpdate(showCovers: Boolean) = update()
+    override fun onCoverSettingsChanged() = update()
-    override fun onQualityCoverUpdate(doQualityCovers: Boolean) = update()
 
     /*
      * An immutable condensed variant of the current playback state, used so that PlaybackStateManager