Merge branch 'develop'

CHANGELOG.md

@@ -3,6 +3,19 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+## [v1.2.8] - 2020-11-27
+### Added
+- Albums / Countries / Tags: pinch to change tile size
+- Album picker: added a field to filter by name
+- check free space before moving entries
+- SVG source viewer
+
+### Changed
+- Navigation: changed page history handling
+- Info: improved layout, especially for XMP
+- About: improved layout
+- faster locating of new entries
+
 ## [v1.2.7] - 2020-11-15
 ### Added
 - Support for TIFF images (single page)

android/app/build.gradle

@@ -98,7 +98,7 @@ repositories {
 
 dependencies {
     implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.9'
-    implementation 'androidx.core:core-ktx:1.5.0-alpha04' // v1.5.0-alpha02+ for ShortcutManagerCompat.setDynamicShortcuts
+    implementation 'androidx.core:core-ktx:1.5.0-alpha05' // v1.5.0-alpha02+ for ShortcutManagerCompat.setDynamicShortcuts
     implementation 'androidx.exifinterface:exifinterface:1.3.1'
     implementation 'com.commonsware.cwac:document:0.4.1'
     implementation 'com.drewnoakes:metadata-extractor:2.15.0'
@@ -109,6 +109,9 @@ dependencies {
     implementation 'com.github.deckerst:Android-TiffBitmapFactory:7efb450636'
     implementation 'com.github.bumptech.glide:glide:4.11.0'
 
+    // TODO TLAD remove when this is fixed: https://github.com/firebase/firebase-android-sdk/issues/1662 https://github.com/FirebaseExtended/flutterfire/issues/3990
+    implementation 'com.google.firebase:firebase-analytics:18.0.0'
+
     kapt 'androidx.annotation:annotation:1.1.0'
     kapt 'com.github.bumptech.glide:compiler:4.11.0'
 

android/app/google-services.json

@@ -14,6 +14,14 @@
         }
       },
       "oauth_client": [
+        {
+          "client_id": "100907092477-1mredcehjo66opfirr6k3kokjqmc99ee.apps.googleusercontent.com",
+          "client_type": 1,
+          "android_info": {
+            "package_name": "deckers.thibault.aves",
+            "certificate_hash": "59a50013fa7a2f97911b52d681cafaebf83505e8"
+          }
+        },
         {
           "client_id": "100907092477-ml1c4hr4l24ekg7l7nqid06n03kek6c8.apps.googleusercontent.com",
           "client_type": 1,
@@ -51,6 +59,14 @@
         }
       },
       "oauth_client": [
+        {
+          "client_id": "100907092477-8vgakbtass73c6dad5mqflq2dd4h4904.apps.googleusercontent.com",
+          "client_type": 1,
+          "android_info": {
+            "package_name": "deckers.thibault.aves.debug",
+            "certificate_hash": "744592fedb021fd82372966a6cb30569579fa9cc"
+          }
+        },
         {
           "client_id": "100907092477-u7sm8gp5t2sotn42oq20ufhtn3craodu.apps.googleusercontent.com",
           "client_type": 3
@@ -80,6 +96,14 @@
         }
       },
       "oauth_client": [
+        {
+          "client_id": "100907092477-4a6968gloaaq70uti1offkk7raduond6.apps.googleusercontent.com",
+          "client_type": 1,
+          "android_info": {
+            "package_name": "deckers.thibault.aves.profile",
+            "certificate_hash": "744592fedb021fd82372966a6cb30569579fa9cc"
+          }
+        },
         {
           "client_id": "100907092477-u7sm8gp5t2sotn42oq20ufhtn3craodu.apps.googleusercontent.com",
           "client_type": 3

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/AppAdapterHandler.kt

@@ -162,6 +162,7 @@ class AppAdapterHandler(private val context: Context) : MethodCallHandler {
         uri ?: return false
 
         val intent = Intent(Intent.ACTION_VIEW)
+            .addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
             .setDataAndType(uri, mimeType)
         return safeStartActivityChooser(title, intent)
     }
@@ -177,12 +178,14 @@ class AppAdapterHandler(private val context: Context) : MethodCallHandler {
         uri ?: return false
 
         val intent = Intent(Intent.ACTION_ATTACH_DATA)
+            .addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
             .setDataAndType(uri, mimeType)
         return safeStartActivityChooser(title, intent)
     }
 
     private fun shareSingle(title: String?, uri: Uri, mimeType: String): Boolean {
         val intent = Intent(Intent.ACTION_SEND)
+            .addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
             .setType(mimeType)
         when (uri.scheme?.toLowerCase(Locale.ROOT)) {
             ContentResolver.SCHEME_FILE -> {
@@ -190,7 +193,6 @@ class AppAdapterHandler(private val context: Context) : MethodCallHandler {
                 val applicationId = context.applicationContext.packageName
                 val apkUri = FileProvider.getUriForFile(context, "$applicationId.fileprovider", File(path))
                 intent.putExtra(Intent.EXTRA_STREAM, apkUri)
-                intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
             }
             else -> intent.putExtra(Intent.EXTRA_STREAM, uri)
         }
@@ -222,25 +224,32 @@ class AppAdapterHandler(private val context: Context) : MethodCallHandler {
         }
 
         val intent = Intent(Intent.ACTION_SEND_MULTIPLE)
+            .addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
             .putParcelableArrayListExtra(Intent.EXTRA_STREAM, uriList)
             .setType(mimeType)
         return safeStartActivityChooser(title, intent)
     }
 
     private fun safeStartActivity(intent: Intent): Boolean {
-        val canResolve = intent.resolveActivity(context.packageManager) != null
-        if (canResolve) {
+        if (intent.resolveActivity(context.packageManager) == null) return false
+        try {
             context.startActivity(intent)
+            return true
+        } catch (e: SecurityException) {
+            Log.w(LOG_TAG, "failed to start activity for intent=$intent", e)
         }
-        return canResolve
+        return false
     }
 
     private fun safeStartActivityChooser(title: String?, intent: Intent): Boolean {
-        val canResolve = intent.resolveActivity(context.packageManager) != null
-        if (canResolve) {
+        if (intent.resolveActivity(context.packageManager) == null) return false
+        try {
             context.startActivity(Intent.createChooser(intent, title))
+            return true
+        } catch (e: SecurityException) {
+            Log.w(LOG_TAG, "failed to start activity chooser for intent=$intent", e)
         }
-        return canResolve
+        return false
     }
 
     companion object {

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataHandler.kt

@@ -103,7 +103,10 @@ class MetadataHandler(private val context: Context) : MethodCallHandler {
 
                     for (dir in metadata.directories.filter { it.tagCount > 0 && it !is FileTypeDirectory }) {
                         // directory name
-                        val dirName = dir.name ?: ""
+                        var dirName = dir.name
+                        // optional parent to distinguish child directories of the same type
+                        dir.parent?.name?.let { dirName = "$it/$dirName" }
+
                         val dirMap = metadataMap.getOrDefault(dirName, HashMap())
                         metadataMap[dirName] = dirMap
 

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/StorageHandler.kt

@@ -28,6 +28,7 @@ class StorageHandler(private val context: Context) : MethodCallHandler {
                 }
                 result.success(volumes)
             }
+            "getFreeSpace" -> getFreeSpace(call, result)
             "getGrantedDirectories" -> result.success(ArrayList(PermissionManager.getGrantedDirs(context)))
             "getInaccessibleDirectories" -> getInaccessibleDirectories(call, result)
             "revokeDirectoryAccess" -> revokeDirectoryAccess(call, result)
@@ -62,6 +63,35 @@ class StorageHandler(private val context: Context) : MethodCallHandler {
             return volumes
         }
 
+    private fun getFreeSpace(call: MethodCall, result: MethodChannel.Result) {
+        val path = call.argument<String>("path")
+        if (path == null) {
+            result.error("getFreeSpace-args", "failed because of missing arguments", null)
+            return
+        }
+
+        val sm = context.getSystemService(StorageManager::class.java)
+        if (sm == null) {
+            result.error("getFreeSpace-sm", "failed because of missing Storage Manager", null)
+            return
+        }
+
+        val file = File(path)
+        val volume = sm.getStorageVolume(file)
+        if (volume == null) {
+            result.error("getFreeSpace-volume", "failed because of missing volume for path=$path", null)
+            return
+        }
+
+        // `StorageStatsManager` `getFreeBytes()` is only available from API 26,
+        // and non-primary volume UUIDs cannot be used with it
+        try {
+            result.success(file.freeSpace)
+        } catch (e: SecurityException) {
+            result.error("getFreeSpace-security", "failed because of missing access", e.message)
+        }
+    }
+
     private fun getInaccessibleDirectories(call: MethodCall, result: MethodChannel.Result) {
         val dirPaths = call.argument<List<String>>("dirPaths")
         if (dirPaths == null) {

android/app/src/main/kotlin/deckers/thibault/aves/metadata/ExifInterfaceHelper.kt

@@ -217,8 +217,11 @@ object ExifInterfaceHelper {
         // so that we can rely on metadata-extractor descriptions
         val dirs = DirType.values().map { Pair(it, it.createDirectory()) }.toMap()
 
+        // exclude Exif directory when it only includes image size
+        val isUselessExif: (Map<String, String>) -> Boolean = { it.size == 2 && it.containsKey("Image Height") && it.containsKey("Image Width") }
+
         return HashMap<String, Map<String, String>>().apply {
-            put("Exif", describeDir(exif, dirs, baseTags))
+            put("Exif", describeDir(exif, dirs, baseTags).takeUnless(isUselessExif) ?: hashMapOf())
             put("Exif Thumbnail", describeDir(exif, dirs, thumbnailTags))
             put(Metadata.DIR_GPS, describeDir(exif, dirs, gpsTags))
             put(Metadata.DIR_XMP, describeDir(exif, dirs, xmpTags))

android/app/src/main/kotlin/deckers/thibault/aves/model/SourceImageEntry.kt

@@ -122,17 +122,15 @@ class SourceImageEntry {
         if (isVideo) {
             fillVideoByMediaMetadataRetriever(context)
             if (isSized && hasDuration) return this
-        }
-        // skip metadata-extractor for raw images because it reports the decoded dimensions instead of the raw dimensions
-        if (!MimeTypes.isRaw(sourceMimeType) && MimeTypes.isSupportedByMetadataExtractor(sourceMimeType)) {
+            fillByMetadataExtractor(context)
+        } else {
             fillByMetadataExtractor(context)
             if (isSized && foundExif) return this
-        }
-        if (ExifInterface.isSupportedMimeType(sourceMimeType)) {
             fillByExifInterface(context)
-            if (isSized) return this
         }
-        fillByBitmapDecode(context)
+        if (!isSized) {
+            fillByBitmapDecode(context)
+        }
         return this
     }
 
@@ -156,6 +154,9 @@ class SourceImageEntry {
 
     // finds: width, height, orientation, date, duration
     private fun fillByMetadataExtractor(context: Context) {
+        // skip raw images because `metadata-extractor` reports the decoded dimensions instead of the raw dimensions
+        if (!MimeTypes.isSupportedByMetadataExtractor(sourceMimeType) || MimeTypes.isRaw(sourceMimeType)) return
+
         try {
             StorageUtils.openInputStream(context, uri)?.use { input ->
                 val metadata = ImageMetadataReader.readMetadata(input)
@@ -206,6 +207,8 @@ class SourceImageEntry {
 
     // finds: width, height, orientation, date
     private fun fillByExifInterface(context: Context) {
+        if (!ExifInterface.isSupportedMimeType(sourceMimeType)) return;
+
         try {
             StorageUtils.openInputStream(context, uri)?.use { input ->
                 val exif = ExifInterface(input)

android/app/src/main/kotlin/deckers/thibault/aves/model/provider/ImageProvider.kt

@@ -182,7 +182,7 @@ abstract class ImageProvider {
                 }
 
                 if (newFields.isEmpty()) {
-                    cont.resumeWithException(Exception("failed to get item details from provider at contentUri=$contentUri"))
+                    cont.resumeWithException(Exception("failed to get item details from provider at contentUri=$contentUri (from newUri=$newUri)"))
                 } else {
                     cont.resume(newFields)
                 }

android/app/src/main/kotlin/deckers/thibault/aves/model/provider/MediaStoreImageProvider.kt

@@ -47,10 +47,10 @@ class MediaStoreImageProvider : ImageProvider() {
             val contentUri = ContentUris.withAppendedId(VIDEO_CONTENT_URI, id)
             if (fetchFrom(context, alwaysValid, onSuccess, contentUri, VIDEO_PROJECTION) > 0) return
         }
-        // the uri can be a file media uri (e.g. "content://0@media/external/file/30050")
+        // the uri can be a file media URI (e.g. "content://0@media/external/file/30050")
         // without an equivalent image/video if it is shared from a file browser
         // but the file is not publicly visible
-        if (fetchFrom(context, alwaysValid, onSuccess, uri, BASE_PROJECTION) > 0) return
+        if (fetchFrom(context, alwaysValid, onSuccess, uri, BASE_PROJECTION, fileMimeType = mimeType) > 0) return
 
         callback.onFailure(Exception("failed to fetch entry at uri=$uri"))
     }
@@ -87,6 +87,7 @@ class MediaStoreImageProvider : ImageProvider() {
         handleNewEntry: NewEntryHandler,
         contentUri: Uri,
         projection: Array<String>,
+        fileMimeType: String? = null,
     ): Int {
         var newEntryCount = 0
         val orderBy = "${MediaStore.MediaColumns.DATE_MODIFIED} DESC"
@@ -123,45 +124,51 @@ class MediaStoreImageProvider : ImageProvider() {
                         // for multiple items, `contentUri` is the root without ID,
                         // but for single items, `contentUri` already contains the ID
                         val itemUri = if (contentUriContainsId) contentUri else ContentUris.withAppendedId(contentUri, contentId.toLong())
-                        val mimeType = cursor.getString(mimeTypeColumn)
+                        // `mimeType` can be registered as null for file media URIs with unsupported media types (e.g. TIFF on old devices)
+                        // in that case we try to use the mime type provided along the URI
+                        val mimeType: String? = cursor.getString(mimeTypeColumn) ?: fileMimeType
                         val width = cursor.getInt(widthColumn)
                         val height = cursor.getInt(heightColumn)
                         val durationMillis = if (durationColumn != -1) cursor.getLong(durationColumn) else 0L
 
-                        var entryMap: FieldMap = hashMapOf(
-                            "uri" to itemUri.toString(),
-                            "path" to cursor.getString(pathColumn),
-                            "sourceMimeType" to mimeType,
-                            "width" to width,
-                            "height" to height,
-                            "sourceRotationDegrees" to if (orientationColumn != -1) cursor.getInt(orientationColumn) else 0,
-                            "sizeBytes" to cursor.getLong(sizeColumn),
-                            "title" to cursor.getString(titleColumn),
-                            "dateModifiedSecs" to dateModifiedSecs,
-                            "sourceDateTakenMillis" to if (dateTakenColumn != -1) cursor.getLong(dateTakenColumn) else null,
-                            "durationMillis" to durationMillis,
-                            // only for map export
-                            "contentId" to contentId,
-                        )
+                        if (mimeType == null) {
+                            Log.w(LOG_TAG, "failed to make entry from uri=$itemUri because of null MIME type")
+                        } else {
+                            var entryMap: FieldMap = hashMapOf(
+                                "uri" to itemUri.toString(),
+                                "path" to cursor.getString(pathColumn),
+                                "sourceMimeType" to mimeType,
+                                "width" to width,
+                                "height" to height,
+                                "sourceRotationDegrees" to if (orientationColumn != -1) cursor.getInt(orientationColumn) else 0,
+                                "sizeBytes" to cursor.getLong(sizeColumn),
+                                "title" to cursor.getString(titleColumn),
+                                "dateModifiedSecs" to dateModifiedSecs,
+                                "sourceDateTakenMillis" to if (dateTakenColumn != -1) cursor.getLong(dateTakenColumn) else null,
+                                "durationMillis" to durationMillis,
+                                // only for map export
+                                "contentId" to contentId,
+                            )
 
-                        if (MimeTypes.isRaw(mimeType)
-                            || (width <= 0 || height <= 0) && needSize(mimeType)
-                            || durationMillis == 0L && needDuration
-                        ) {
-                            // Some images are incorrectly registered in the Media Store,
-                            // missing some attributes such as width, height, orientation.
-                            // Also, the reported size of raw images is inconsistent across devices
-                            // and Android versions (sometimes the raw size, sometimes the decoded size).
-                            val entry = SourceImageEntry(entryMap).fillPreCatalogMetadata(context)
-                            entryMap = entry.toMap()
-                        }
+                            if (MimeTypes.isRaw(mimeType)
+                                || (width <= 0 || height <= 0) && needSize(mimeType)
+                                || durationMillis == 0L && needDuration
+                            ) {
+                                // Some images are incorrectly registered in the Media Store,
+                                // missing some attributes such as width, height, orientation.
+                                // Also, the reported size of raw images is inconsistent across devices
+                                // and Android versions (sometimes the raw size, sometimes the decoded size).
+                                val entry = SourceImageEntry(entryMap).fillPreCatalogMetadata(context)
+                                entryMap = entry.toMap()
+                            }
 
-                        handleNewEntry(entryMap)
-                        // TODO TLAD is this necessary?
-                        if (newEntryCount % 30 == 0) {
-                            delay(10)
+                            handleNewEntry(entryMap)
+                            // TODO TLAD is this necessary?
+                            if (newEntryCount % 30 == 0) {
+                                delay(10)
+                            }
+                            newEntryCount++
                         }
-                        newEntryCount++
                     }
                 }
                 cursor.close()
@@ -314,7 +321,8 @@ class MediaStoreImageProvider : ImageProvider() {
             MediaStore.MediaColumns._ID,
             MediaColumns.PATH,
             MediaStore.MediaColumns.MIME_TYPE,
-            MediaStore.MediaColumns.SIZE,  // TODO TLAD use `DISPLAY_NAME` instead/along `TITLE`?
+            MediaStore.MediaColumns.SIZE,
+            // TODO TLAD use `DISPLAY_NAME` instead/along `TITLE`?
             MediaStore.MediaColumns.TITLE,
             MediaStore.MediaColumns.WIDTH,
             MediaStore.MediaColumns.HEIGHT,

android/app/src/main/kotlin/deckers/thibault/aves/utils/MimeTypes.kt

@@ -44,7 +44,7 @@ object MimeTypes {
         else -> isVideo(mimeType)
     }
 
-    fun isRaw(mimeType: String?): Boolean {
+    fun isRaw(mimeType: String): Boolean {
         return when (mimeType) {
             ARW, CR2, DNG, NEF, NRW, ORF, PEF, RAF, RW2, SRW -> true
             else -> false

android/build.gradle

@@ -6,11 +6,11 @@ buildscript {
         jcenter()
     }
     dependencies {
-        // TODO TLAD upgrade AGP to 4+ when this is fixed: https://github.com/flutter/flutter/issues/58247
+        // TODO TLAD upgrade AGP to 4+ when this lands on stable: https://github.com/flutter/flutter/pull/70808
         classpath 'com.android.tools.build:gradle:3.6.4'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath 'com.google.gms:google-services:4.3.4'
-        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.3.0'
+        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.4.1'
     }
 }
 

lib/image_providers/uri_picture_provider.dart

@@ -8,10 +8,13 @@ class UriPicture extends PictureProvider<UriPicture> {
   const UriPicture({
     @required this.uri,
     @required this.mimeType,
+    this.colorFilter,
   }) : assert(uri != null);
 
   final String uri, mimeType;
 
+  final ColorFilter colorFilter;
+
   @override
   Future<UriPicture> obtainKey(PictureConfiguration configuration) {
     return SynchronousFuture<UriPicture>(this);
@@ -34,22 +37,22 @@ class UriPicture extends PictureProvider<UriPicture> {
 
     final decoder = SvgPicture.svgByteDecoder;
     if (onError != null) {
-      final future = decoder(data, null, key.toString());
+      final future = decoder(data, colorFilter, key.toString());
       unawaited(future.catchError(onError));
       return future;
     }
-    return decoder(data, null, key.toString());
+    return decoder(data, colorFilter, key.toString());
   }
 
   @override
   bool operator ==(Object other) {
     if (other.runtimeType != runtimeType) return false;
-    return other is UriPicture && other.uri == uri;
+    return other is UriPicture && other.uri == uri && other.colorFilter == colorFilter;
   }
 
   @override
-  int get hashCode => uri.hashCode;
+  int get hashCode => hashValues(uri, colorFilter);
 
   @override
-  String toString() => '${objectRuntimeType(this, 'UriPicture')}(uri=$uri, mimeType=$mimeType)';
+  String toString() => '${objectRuntimeType(this, 'UriPicture')}(uri=$uri, mimeType=$mimeType, colorFilter=$colorFilter)';
 }

lib/main.dart

@@ -2,10 +2,10 @@ import 'dart:isolate';
 import 'dart:ui';
 
 import 'package:aves/model/settings/settings.dart';
-import 'package:aves/utils/route_tracker.dart';
-import 'package:aves/widgets/common/data_providers/settings_provider.dart';
-import 'package:aves/widgets/common/icons.dart';
-import 'package:aves/widgets/common/routes.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/widgets/common/behaviour/route_tracker.dart';
+import 'package:aves/widgets/common/behaviour/routes.dart';
+import 'package:aves/widgets/common/providers/settings_provider.dart';
 import 'package:aves/widgets/home_page.dart';
 import 'package:aves/widgets/welcome_page.dart';
 import 'package:firebase_analytics/firebase_analytics.dart';
@@ -57,6 +57,7 @@ class _AvesAppState extends State<AvesApp> {
     accentColor: accentColor,
     scaffoldBackgroundColor: Colors.grey[900],
     buttonColor: accentColor,
+    dialogBackgroundColor: Colors.grey[850],
     toggleableActiveColor: accentColor,
     tooltipTheme: TooltipThemeData(
       verticalOffset: 32,

lib/model/actions/chip_actions.dart

@@ -1,4 +1,4 @@
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/widgets.dart';
 
 enum ChipSetAction {

lib/model/actions/collection_actions.dart

@@ -1,13 +1,14 @@
 enum CollectionAction {
   addShortcut,
-  copy,
+  sort,
   group,
-  move,
   refresh,
-  refreshMetadata,
   select,
   selectAll,
   selectNone,
-  sort,
   stats,
+  // apply to entry set
+  copy,
+  move,
+  refreshMetadata,
 }

lib/model/actions/entry_actions.dart

@@ -1,5 +1,5 @@
-import 'package:aves/widgets/common/icons.dart';
-import 'package:flutter/material.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:flutter/widgets.dart';
 
 enum EntryAction {
   delete,
@@ -15,6 +15,7 @@ enum EntryAction {
   setAs,
   share,
   toggleFavourite,
+  viewSource,
   debug,
 }
 
@@ -31,6 +32,7 @@ class EntryActions {
     EntryAction.delete,
     EntryAction.rename,
     EntryAction.print,
+    EntryAction.viewSource,
   ];
 
   static const externalApp = [
@@ -64,6 +66,8 @@ extension ExtraEntryAction on EntryAction {
         return 'Print';
       case EntryAction.share:
         return 'Share';
+      case EntryAction.viewSource:
+        return 'View source';
       // external app actions
       case EntryAction.edit:
         return 'Edit with…';
@@ -101,6 +105,8 @@ extension ExtraEntryAction on EntryAction {
         return AIcons.print;
       case EntryAction.share:
         return AIcons.share;
+      case EntryAction.viewSource:
+        return AIcons.vector;
       // external app actions
       case EntryAction.edit:
       case EntryAction.open:

lib/model/entry_cache.dart

@@ -1,8 +1,8 @@
 import 'dart:async';
 import 'dart:math';
 
-import 'package:aves/widgets/common/image_providers/thumbnail_provider.dart';
-import 'package:aves/widgets/common/image_providers/uri_image_provider.dart';
+import 'package:aves/image_providers/thumbnail_provider.dart';
+import 'package:aves/image_providers/uri_image_provider.dart';
 
 class EntryCache {
   static Future<void> evict(

lib/model/filters/album.dart

@@ -1,8 +1,9 @@
+import 'package:aves/image_providers/app_icon_image_provider.dart';
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/utils/android_file_utils.dart';
-import 'package:aves/widgets/common/icons.dart';
-import 'package:aves/widgets/common/image_providers/app_icon_image_provider.dart';
+import 'package:aves/widgets/common/identity/aves_icons.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 import 'package:palette_generator/palette_generator.dart';

lib/model/filters/favourite.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 

lib/model/filters/location.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 

lib/model/filters/mime.dart

@@ -1,7 +1,7 @@
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/model/mime_types.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/utils/mime_utils.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
@@ -35,7 +35,7 @@ class MimeFilter extends CollectionFilter {
       _label ??= lowMime.split('/')[0].toUpperCase();
     } else {
       _filter = (entry) => entry.mimeType == lowMime;
-      _label = MimeTypes.displayType(lowMime);
+      _label = MimeUtils.displayType(lowMime);
     }
     _icon ??= AIcons.vector;
   }

lib/model/filters/query.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';

lib/model/filters/tag.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 

lib/model/highlight.dart

@@ -0,0 +1,24 @@
+import 'dart:collection';
+
+import 'package:flutter/foundation.dart';
+
+class HighlightInfo extends ChangeNotifier {
+  final Queue<Object> _items = Queue();
+
+  void add(Object item) {
+    if (_items.contains(item)) return;
+
+    _items.addFirst(item);
+    while (_items.length > 5) {
+      _items.removeLast();
+    }
+    notifyListeners();
+  }
+
+  void remove(Object item) {
+    _items.removeWhere((element) => element == item);
+    notifyListeners();
+  }
+
+  bool contains(Object item) => _items.contains(item);
+}

lib/model/image_entry.dart

@@ -8,21 +8,24 @@ import 'package:aves/services/image_file_service.dart';
 import 'package:aves/services/metadata_service.dart';
 import 'package:aves/services/service_policy.dart';
 import 'package:aves/utils/change_notifier.dart';
+import 'package:aves/utils/math_utils.dart';
 import 'package:aves/utils/time_utils.dart';
 import 'package:collection/collection.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:geocoder/geocoder.dart';
+import 'package:latlong/latlong.dart';
 import 'package:path/path.dart' as ppath;
-import 'package:tuple/tuple.dart';
 
-import 'mime_types.dart';
+import '../ref/mime_types.dart';
 
 class ImageEntry {
   String uri;
   String _path, _directory, _filename, _extension;
   int contentId;
   final String sourceMimeType;
+
+  // TODO TLAD use SVG viewport as width/height
   int width;
   int height;
   int sourceRotationDegrees;
@@ -37,6 +40,9 @@ class ImageEntry {
 
   final AChangeNotifier imageChangeNotifier = AChangeNotifier(), metadataChangeNotifier = AChangeNotifier(), addressChangeNotifier = AChangeNotifier();
 
+  // TODO TLAD make it dynamic if it depends on OS/lib versions
+  static const List<String> undecodable = [MimeTypes.crw, MimeTypes.psd];
+
   ImageEntry({
     this.uri,
     String path,
@@ -56,7 +62,7 @@ class ImageEntry {
     this.dateModifiedSecs = dateModifiedSecs;
   }
 
-  bool get canDecode => !MimeTypes.undecodable.contains(mimeType);
+  bool get canDecode => !undecodable.contains(mimeType);
 
   ImageEntry copyWith({
     @required String uri,
@@ -217,7 +223,12 @@ class ImageEntry {
     }
   }
 
-  bool get isPortrait => rotationDegrees % 180 == 90;
+  // The additional comparison of width to height is a workaround for badly registered entries.
+  // e.g. a portrait FHD video should be registered as width=1920, height=1080, orientation=90,
+  // but is incorrectly registered in the Media Store as width=1080, height=1920, orientation=0
+  // Double-checking the width/height during loading or cataloguing is the proper solution,
+  // but it would take space and time, so a basic workaround will do.
+  bool get isPortrait => rotationDegrees % 180 == 90 && (catalogMetadata?.rotationDegrees == null || width > height);
 
   String get resolutionText {
     final w = width ?? '?';
@@ -288,9 +299,14 @@ class ImageEntry {
 
   bool get isLocated => _addressDetails != null;
 
-  Tuple2<double, double> get latLng => isCatalogued ? Tuple2(_catalogMetadata.latitude, _catalogMetadata.longitude) : null;
+  LatLng get latLng => isCatalogued ? LatLng(_catalogMetadata.latitude, _catalogMetadata.longitude) : null;
 
-  String get geoUri => hasGps ? 'geo:${_catalogMetadata.latitude},${_catalogMetadata.longitude}?q=${_catalogMetadata.latitude},${_catalogMetadata.longitude}' : null;
+  String get geoUri {
+    if (!hasGps) return null;
+    final latitude = roundToPrecision(_catalogMetadata.latitude, decimals: 6);
+    final longitude = roundToPrecision(_catalogMetadata.longitude, decimals: 6);
+    return 'geo:$latitude,$longitude?q=$latitude,$longitude';
+  }
 
   List<String> get xmpSubjects => _catalogMetadata?.xmpSubjects?.split(';')?.where((tag) => tag.isNotEmpty)?.toList() ?? [];
 
@@ -359,7 +375,6 @@ class ImageEntry {
         final address = addresses.first;
         addressDetails = AddressDetails(
           contentId: contentId,
-          addressLine: address.addressLine,
           countryCode: address.countryCode,
           countryName: address.countryName,
           adminArea: address.adminArea,
@@ -371,11 +386,29 @@ class ImageEntry {
     }
   }
 
+  Future<String> findAddressLine() async {
+    final latitude = _catalogMetadata?.latitude;
+    final longitude = _catalogMetadata?.longitude;
+    if (latitude == null || longitude == null || (latitude == 0 && longitude == 0)) return null;
+
+    final coordinates = Coordinates(latitude, longitude);
+    try {
+      final addresses = await Geocoder.local.findAddressesFromCoordinates(coordinates);
+      if (addresses != null && addresses.isNotEmpty) {
+        final address = addresses.first;
+        return address.addressLine;
+      }
+    } catch (error, stackTrace) {
+      debugPrint('$runtimeType findAddressLine failed with path=$path coordinates=$coordinates error=$error\n$stackTrace');
+    }
+    return null;
+  }
+
   String get shortAddress {
     if (!isLocated) return '';
 
-    // admin area examples: Seoul, Geneva, null
-    // locality examples: Mapo-gu, Geneva, Annecy
+    // `admin area` examples: Seoul, Geneva, null
+    // `locality` examples: Mapo-gu, Geneva, Annecy
     return {
       _addressDetails.countryName,
       _addressDetails.adminArea,
@@ -383,12 +416,13 @@ class ImageEntry {
     }.where((part) => part != null && part.isNotEmpty).join(', ');
   }
 
-  bool search(String query) {
-    if (bestTitle?.toUpperCase()?.contains(query) ?? false) return true;
-    if (_catalogMetadata?.xmpSubjects?.toUpperCase()?.contains(query) ?? false) return true;
-    if (_addressDetails?.addressLine?.toUpperCase()?.contains(query) ?? false) return true;
-    return false;
-  }
+  bool search(String query) => {
+        bestTitle,
+        _catalogMetadata?.xmpSubjects,
+        _addressDetails?.countryName,
+        _addressDetails?.adminArea,
+        _addressDetails?.locality,
+      }.any((s) => s != null && s.toUpperCase().contains(query));
 
   Future<void> _applyNewFields(Map newFields) async {
     final uri = newFields['uri'];

lib/model/image_metadata.dart

@@ -48,7 +48,7 @@ class CatalogMetadata {
     this.xmpTitleDescription,
     double latitude,
     double longitude,
-  })
+  })  
   // Geocoder throws an IllegalArgumentException when a coordinate has a funky values like 1.7056881853375E7
   : latitude = latitude == null || latitude < -90.0 || latitude > 90.0 ? null : latitude,
         longitude = longitude == null || longitude < -180.0 || longitude > 180.0 ? null : longitude;
@@ -142,13 +142,12 @@ class OverlayMetadata {
 
 class AddressDetails {
   final int contentId;
-  final String addressLine, countryCode, countryName, adminArea, locality;
+  final String countryCode, countryName, adminArea, locality;
 
   String get place => locality != null && locality.isNotEmpty ? locality : adminArea;
 
   AddressDetails({
     this.contentId,
-    this.addressLine,
     this.countryCode,
     this.countryName,
     this.adminArea,
@@ -160,7 +159,6 @@ class AddressDetails {
   }) {
     return AddressDetails(
       contentId: contentId ?? this.contentId,
-      addressLine: addressLine,
       countryCode: countryCode,
       countryName: countryName,
       adminArea: adminArea,
@@ -171,7 +169,6 @@ class AddressDetails {
   factory AddressDetails.fromMap(Map map) {
     return AddressDetails(
       contentId: map['contentId'],
-      addressLine: map['addressLine'] ?? '',
       countryCode: map['countryCode'] ?? '',
       countryName: map['countryName'] ?? '',
       adminArea: map['adminArea'] ?? '',
@@ -181,7 +178,6 @@ class AddressDetails {
 
   Map<String, dynamic> toMap() => {
         'contentId': contentId,
-        'addressLine': addressLine,
         'countryCode': countryCode,
         'countryName': countryName,
         'adminArea': adminArea,
@@ -190,7 +186,7 @@ class AddressDetails {
 
   @override
   String toString() {
-    return 'AddressDetails{contentId=$contentId, addressLine=$addressLine, countryCode=$countryCode, countryName=$countryName, adminArea=$adminArea, locality=$locality}';
+    return 'AddressDetails{contentId=$contentId, countryCode=$countryCode, countryName=$countryName, adminArea=$adminArea, locality=$locality}';
   }
 }
 

lib/model/metadata_db.dart

@@ -143,7 +143,7 @@ class MetadataDb {
     await init();
   }
 
-  void removeIds(List<int> contentIds) async {
+  void removeIds(Set<int> contentIds, {@required bool updateFavourites}) async {
     if (contentIds == null || contentIds.isEmpty) return;
 
     final stopwatch = Stopwatch()..start();
@@ -157,7 +157,9 @@ class MetadataDb {
       batch.delete(dateTakenTable, where: where, whereArgs: whereArgs);
       batch.delete(metadataTable, where: where, whereArgs: whereArgs);
       batch.delete(addressTable, where: where, whereArgs: whereArgs);
-      batch.delete(favouriteTable, where: where, whereArgs: whereArgs);
+      if (updateFavourites) {
+        batch.delete(favouriteTable, where: where, whereArgs: whereArgs);
+      }
     });
     await batch.commit(noResult: true);
     debugPrint('$runtimeType removeIds complete in ${stopwatch.elapsed.inMilliseconds}ms for ${contentIds.length} entries');

lib/model/settings/coordinate_format.dart

@@ -1,5 +1,5 @@
 import 'package:aves/utils/geo_utils.dart';
-import 'package:tuple/tuple.dart';
+import 'package:latlong/latlong.dart';
 
 enum CoordinateFormat { dms, decimal }
 
@@ -15,12 +15,12 @@ extension ExtraCoordinateFormat on CoordinateFormat {
     }
   }
 
-  String format(Tuple2<double, double> latLng) {
+  String format(LatLng latLng) {
     switch (this) {
       case CoordinateFormat.dms:
         return toDMS(latLng).join(', ');
       case CoordinateFormat.decimal:
-        return [latLng.item1, latLng.item2].map((n) => n.toStringAsFixed(6)).join(', ');
+        return [latLng.latitude, latLng.longitude].map((n) => n.toStringAsFixed(6)).join(', ');
       default:
         return toString();
     }

lib/model/settings/settings.dart

@@ -29,11 +29,11 @@ class Settings extends ChangeNotifier {
   static const keepScreenOnKey = 'keep_screen_on';
   static const homePageKey = 'home_page';
   static const catalogTimeZoneKey = 'catalog_time_zone';
+  static const tileExtentPrefixKey = 'tile_extent_';
 
   // collection
   static const collectionGroupFactorKey = 'collection_group_factor';
   static const collectionSortFactorKey = 'collection_sort_factor';
-  static const collectionTileExtentKey = 'collection_tile_extent';
   static const showThumbnailLocationKey = 'show_thumbnail_location';
   static const showThumbnailRawKey = 'show_thumbnail_raw';
   static const showThumbnailVideoDurationKey = 'show_thumbnail_video_duration';
@@ -112,6 +112,12 @@ class Settings extends ChangeNotifier {
 
   set catalogTimeZone(String newValue) => setAndNotify(catalogTimeZoneKey, newValue);
 
+  double getTileExtent(String routeName) => _prefs.getDouble(tileExtentPrefixKey + routeName) ?? 0;
+
+  // do not notify, as tile extents are only used internally by `TileExtentManager`
+  // and should not trigger rebuilding by change notification
+  void setTileExtent(String routeName, double newValue) => setAndNotify(tileExtentPrefixKey + routeName, newValue, notify: false);
+
   // collection
 
   EntryGroupFactor get collectionGroupFactor => getEnumOrDefault(collectionGroupFactorKey, EntryGroupFactor.month, EntryGroupFactor.values);
@@ -122,12 +128,6 @@ class Settings extends ChangeNotifier {
 
   set collectionSortFactor(EntrySortFactor newValue) => setAndNotify(collectionSortFactorKey, newValue.toString());
 
-  double get collectionTileExtent => _prefs.getDouble(collectionTileExtentKey) ?? 0;
-
-  // do not notify, as `collectionTileExtent` is only used internally by `TileExtentManager`
-  // and should not trigger rebuilding by change notification
-  set collectionTileExtent(double newValue) => setAndNotify(collectionTileExtentKey, newValue, notify: false);
-
   bool get showThumbnailLocation => getBoolOrDefault(showThumbnailLocationKey, true);
 
   set showThumbnailLocation(bool newValue) => setAndNotify(showThumbnailLocationKey, newValue);
@@ -198,14 +198,6 @@ class Settings extends ChangeNotifier {
 
   set searchHistory(List<CollectionFilter> newValue) => setAndNotify(searchHistoryKey, newValue.map((filter) => filter.toJson()).toList());
 
-  // utils
-
-  // `RoutePredicate`
-  RoutePredicate navRemoveRoutePredicate(String pushedRouteName) {
-    final home = homePage.routeName;
-    return (route) => pushedRouteName != home && route.settings?.name == home;
-  }
-
   // convenience methods
 
   // ignore: avoid_positional_boolean_parameters

lib/model/source/collection_lens.dart

@@ -4,7 +4,6 @@ import 'dart:collection';
 import 'package:aves/model/filters/album.dart';
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/model/settings/settings.dart';
 import 'package:aves/model/source/collection_source.dart';
 import 'package:aves/model/source/tag.dart';
 import 'package:aves/utils/change_notifier.dart';
@@ -19,7 +18,6 @@ class CollectionLens with ChangeNotifier, CollectionActivityMixin, CollectionSel
   EntryGroupFactor groupFactor;
   EntrySortFactor sortFactor;
   final AChangeNotifier filterChangeNotifier = AChangeNotifier();
-  final StreamController<ImageEntry> _highlightController = StreamController.broadcast();
 
   List<ImageEntry> _filteredEntries;
   List<StreamSubscription> _subscriptions = [];
@@ -50,14 +48,6 @@ class CollectionLens with ChangeNotifier, CollectionActivityMixin, CollectionSel
     super.dispose();
   }
 
-  factory CollectionLens.empty() {
-    return CollectionLens(
-      source: CollectionSource(),
-      groupFactor: settings.collectionGroupFactor,
-      sortFactor: settings.collectionSortFactor,
-    );
-  }
-
   CollectionLens derive(CollectionFilter filter) {
     return CollectionLens(
       source: source,
@@ -79,10 +69,6 @@ class CollectionLens with ChangeNotifier, CollectionActivityMixin, CollectionSel
     return _sortedEntries;
   }
 
-  Stream<ImageEntry> get highlightStream => _highlightController.stream;
-
-  void highlight(ImageEntry entry) => _highlightController.add(entry);
-
   bool get showHeaders {
     if (sortFactor == EntrySortFactor.size) return false;
 

lib/model/source/collection_source.dart

@@ -37,7 +37,7 @@ mixin SourceBase {
   void setProgress({@required int done, @required int total}) => _progressStreamController.add(ProgressEvent(done: done, total: total));
 }
 
-class CollectionSource with SourceBase, AlbumMixin, LocationMixin, TagMixin {
+abstract class CollectionSource with SourceBase, AlbumMixin, LocationMixin, TagMixin {
   @override
   List<ImageEntry> get sortedEntriesForFilterList => CollectionLens(
         source: this,
@@ -45,7 +45,7 @@ class CollectionSource with SourceBase, AlbumMixin, LocationMixin, TagMixin {
         sortFactor: EntrySortFactor.date,
       ).sortedEntries;
 
-  ValueNotifier<SourceState> stateNotifier = ValueNotifier<SourceState>(SourceState.ready);
+  ValueNotifier<SourceState> stateNotifier = ValueNotifier(SourceState.ready);
 
   List<DateMetadata> _savedDates;
 
@@ -109,7 +109,7 @@ class CollectionSource with SourceBase, AlbumMixin, LocationMixin, TagMixin {
   }
 
   void updateAfterMove({
-    @required List<ImageEntry> selection,
+    @required Set<ImageEntry> selection,
     @required bool copy,
     @required String destinationAlbum,
     @required Iterable<MoveOpEvent> movedOps,
@@ -163,6 +163,10 @@ class CollectionSource with SourceBase, AlbumMixin, LocationMixin, TagMixin {
   int count(CollectionFilter filter) {
     return _filterEntryCountMap.putIfAbsent(filter, () => _rawEntries.where((entry) => filter.filter(entry)).length);
   }
+
+  Future<void> refresh();
+
+  Future<void> refreshMetadata(Set<ImageEntry> entries);
 }
 
 enum SourceState { loading, cataloguing, locating, ready }

lib/model/source/location.dart

@@ -1,3 +1,5 @@
+import 'dart:math';
+
 import 'package:aves/model/filters/location.dart';
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/image_metadata.dart';
@@ -30,15 +32,25 @@ mixin LocationMixin on SourceBase {
     final todo = byLocated[false] ?? [];
     if (todo.isEmpty) return;
 
-    // cache known locations to avoid querying the geocoder unless necessary
-    // measuring the time it takes to process ~3000 coordinates (with ~10% of duplicates)
-    // does not clearly show whether it is an actual optimization,
-    // as results vary wildly (durations in "min:sec"):
-    // - with no cache: 06:17, 08:36, 08:34
-    // - with cache: 08:28, 05:42, 08:03, 05:58
-    // anyway, in theory it should help!
-    final knownLocations = <Tuple2<double, double>, AddressDetails>{};
-    byLocated[true]?.forEach((entry) => knownLocations.putIfAbsent(entry.latLng, () => entry.addressDetails));
+    // geocoder calls take between 150ms and 250ms
+    // approximation and caching can reduce geocoder usage
+    // for example, for a set of 2932 entries:
+    // - 2476 calls (84%) when approximating to 6 decimal places (~10cm - individual humans)
+    // - 2433 calls (83%) when approximating to 5 decimal places (~1m - individual trees, houses)
+    // - 2277 calls (78%) when approximating to 4 decimal places (~10m - individual street, large buildings)
+    // - 1521 calls (52%) when approximating to 3 decimal places (~100m - neighborhood, street)
+    // -  652 calls (22%) when approximating to 2 decimal places (~1km - town or village)
+    // cf https://en.wikipedia.org/wiki/Decimal_degrees#Precision
+    final latLngFactor = pow(10, 2);
+    Tuple2 approximateLatLng(ImageEntry entry) {
+      final lat = entry.catalogMetadata?.latitude;
+      final lng = entry.catalogMetadata?.longitude;
+      if (lat == null || lng == null) return null;
+      return Tuple2((lat * latLngFactor).round(), (lng * latLngFactor).round());
+    }
+
+    final knownLocations = <Tuple2, AddressDetails>{};
+    byLocated[true]?.forEach((entry) => knownLocations.putIfAbsent(approximateLatLng(entry), () => entry.addressDetails));
 
     var progressDone = 0;
     final progressTotal = todo.length;
@@ -46,13 +58,14 @@ mixin LocationMixin on SourceBase {
 
     final newAddresses = <AddressDetails>[];
     await Future.forEach<ImageEntry>(todo, (entry) async {
-      if (knownLocations.containsKey(entry.latLng)) {
-        entry.addressDetails = knownLocations[entry.latLng]?.copyWith(contentId: entry.contentId);
+      final latLng = approximateLatLng(entry);
+      if (knownLocations.containsKey(latLng)) {
+        entry.addressDetails = knownLocations[latLng]?.copyWith(contentId: entry.contentId);
       } else {
         await entry.locate(background: true);
         // it is intended to insert `null` if the geocoder failed,
         // so that we skip geocoding of following entries with the same coordinates
-        knownLocations[entry.latLng] = entry.addressDetails;
+        knownLocations[latLng] = entry.addressDetails;
       }
       if (entry.isLocated) {
         newAddresses.add(entry.addressDetails);

lib/model/source/media_store_source.dart

@@ -6,6 +6,7 @@ import 'package:aves/model/metadata_db.dart';
 import 'package:aves/model/settings/settings.dart';
 import 'package:aves/model/source/collection_source.dart';
 import 'package:aves/services/image_file_service.dart';
+import 'package:aves/utils/math_utils.dart';
 import 'package:firebase_analytics/firebase_analytics.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_native_timezone/flutter_native_timezone.dart';
@@ -30,14 +31,16 @@ class MediaStoreSource extends CollectionSource {
     debugPrint('$runtimeType init done, elapsed=${stopwatch.elapsed}');
   }
 
+  @override
   Future<void> refresh() async {
     debugPrint('$runtimeType refresh start');
     final stopwatch = Stopwatch()..start();
     stateNotifier.value = SourceState.loading;
+    clearEntries();
 
     final oldEntries = await metadataDb.loadEntries(); // 400ms for 5500 entries
     final knownEntryMap = Map.fromEntries(oldEntries.map((entry) => MapEntry(entry.contentId, entry.dateModifiedSecs)));
-    final obsoleteEntries = await ImageFileService.getObsoleteEntries(knownEntryMap.keys.toList());
+    final obsoleteEntries = (await ImageFileService.getObsoleteEntries(knownEntryMap.keys.toList())).toSet();
     oldEntries.removeWhere((entry) => obsoleteEntries.contains(entry.contentId));
 
     // show known entries
@@ -47,7 +50,7 @@ class MediaStoreSource extends CollectionSource {
     debugPrint('$runtimeType refresh loaded ${oldEntries.length} known entries, elapsed=${stopwatch.elapsed}');
 
     // clean up obsolete entries
-    metadataDb.removeIds(obsoleteEntries);
+    metadataDb.removeIds(obsoleteEntries, updateFavourites: true);
 
     // fetch new entries
     var refreshCount = 10;
@@ -92,9 +95,10 @@ class MediaStoreSource extends CollectionSource {
     );
   }
 
-  // e.g. x=12345, precision=3 should return 13000
-  int ceilBy(num x, int precision) {
-    final factor = pow(10, precision);
-    return (x / factor).ceil() * factor;
+  @override
+  Future<void> refreshMetadata(Set<ImageEntry> entries) {
+    final contentIds = entries.map((entry) => entry.contentId).toSet();
+    metadataDb.removeIds(contentIds, updateFavourites: false);
+    return refresh();
   }
 }

lib/ref/brand_colors.dart

@@ -0,0 +1,21 @@
+import 'package:flutter/painting.dart';
+
+class BrandColors {
+  static const Color adobeIllustrator = Color(0xFFFF9B00);
+  static const Color adobePhotoshop = Color(0xFF2DAAFF);
+  static const Color android = Color(0xFF3DDC84);
+  static const Color flutter = Color(0xFF47D1FD);
+
+  static Color get(String text) {
+    if (text != null) {
+      switch (text.toLowerCase()) {
+        case 'illustrator':
+          return adobeIllustrator;
+        case 'photoshop':
+        case 'lightroom':
+          return adobePhotoshop;
+      }
+    }
+    return null;
+  }
+}

lib/ref/mime_types.dart

@@ -41,17 +41,4 @@ class MimeTypes {
 
   // groups
   static const List<String> rawImages = [arw, cr2, crw, dcr, dng, erf, k25, kdc, mrw, nef, nrw, orf, pef, raf, raw, rw2, sr2, srf, srw, x3f];
-  static const List<String> undecodable = [crw, psd]; // TODO TLAD make it dynamic if it depends on OS/lib versions
-
-  static String displayType(String mime) {
-    final patterns = [
-      RegExp('.*/'), // remove type, keep subtype
-      RegExp('(X-|VND.(WAP.)?)'), // noisy prefixes
-      '+XML', // noisy suffix
-      RegExp('ADOBE\\\.'), // for PSD
-    ];
-    mime = mime.toUpperCase();
-    patterns.forEach((pattern) => mime = mime.replaceFirst(pattern, ''));
-    return mime;
-  }
 }

lib/ref/xmp.dart

@@ -0,0 +1,30 @@
+class XMP {
+  static const namespaceSeparator = ':';
+  static const structFieldSeparator = '/';
+
+  // cf https://exiftool.org/TagNames/XMP.html
+  static const Map<String, String> namespaces = {
+    'aux': 'Auxiliary Exif',
+    'Camera': 'Camera',
+    'crs': 'Camera Raw Settings',
+    'dc': 'Dublin Core',
+    'exif': 'Exif',
+    'GIMP': 'GIMP',
+    'illustrator': 'Illustrator',
+    'Iptc4xmpCore': 'IPTC Core',
+    'lr': 'Lightroom',
+    'MicrosoftPhoto': 'Microsoft Photo',
+    'panorama': 'Panorama',
+    'pdf': 'PDF',
+    'pdfx': 'PDF/X',
+    'photomechanic': 'Photo Mechanic',
+    'photoshop': 'Photoshop',
+    'tiff': 'TIFF',
+    'xmp': 'Basic',
+    'xmpBJ': 'Basic Job Ticket',
+    'xmpDM': 'Dynamic Media',
+    'xmpMM': 'Media Management',
+    'xmpRights': 'Rights Management',
+    'xmpTPg': 'Paged-Text',
+  };
+}

lib/services/android_file_service.dart

@@ -1,5 +1,6 @@
 import 'dart:async';
 
+import 'package:aves/utils/android_file_utils.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:streams_channel/streams_channel.dart';
@@ -18,6 +19,18 @@ class AndroidFileService {
     return [];
   }
 
+  static Future<int> getFreeSpace(StorageVolume volume) async {
+    try {
+      final result = await platform.invokeMethod('getFreeSpace', <String, dynamic>{
+        'path': volume.path,
+      });
+      return result as int;
+    } on PlatformException catch (e) {
+      debugPrint('getFreeSpace failed with code=${e.code}, exception=${e.message}, details=${e.details}}');
+    }
+    return 0;
+  }
+
   static Future<List<String>> getGrantedDirectories() async {
     try {
       final result = await platform.invokeMethod('getGrantedDirectories');

lib/services/image_file_service.dart

@@ -4,7 +4,7 @@ import 'dart:math';
 import 'dart:typed_data';
 
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/model/mime_types.dart';
+import 'package:aves/ref/mime_types.dart';
 import 'package:aves/services/service_policy.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';

lib/theme/durations.dart

@@ -12,8 +12,13 @@ class Durations {
   static const staggeredAnimation = Duration(milliseconds: 375);
   static const dialogFieldReachAnimation = Duration(milliseconds: 300);
 
-  // collection animations
   static const appBarTitleAnimation = Duration(milliseconds: 300);
+  static const appBarActionChangeAnimation = Duration(milliseconds: 200);
+
+  // filter grids animations
+  static const chipDecorationAnimation = Duration(milliseconds: 200);
+
+  // collection animations
   static const filterBarRemovalAnimation = Duration(milliseconds: 400);
   static const collectionOpOverlayAnimation = Duration(milliseconds: 300);
   static const collectionScalingBackgroundAnimation = Duration(milliseconds: 200);
@@ -40,4 +45,5 @@ class Durations {
   static Duration staggeredAnimationDelay = Durations.staggeredAnimation ~/ 6 * timeDilation;
   static const doubleBackTimerDelay = Duration(milliseconds: 1000);
   static const softKeyboardDisplayDelay = Duration(milliseconds: 300);
+  static const searchDebounceDelay = Duration(milliseconds: 250);
 }

lib/theme/icons.dart

@@ -0,0 +1,67 @@
+import 'package:flutter/material.dart';
+import 'package:material_design_icons_flutter/material_design_icons_flutter.dart';
+
+class AIcons {
+  static const IconData allCollection = Icons.collections_outlined;
+  static const IconData image = Icons.photo_outlined;
+  static const IconData video = Icons.movie_outlined;
+  static const IconData audio = Icons.audiotrack_outlined;
+  static const IconData vector = Icons.code_outlined;
+
+  static const IconData android = Icons.android;
+  static const IconData checked = Icons.done_outlined;
+  static const IconData date = Icons.calendar_today_outlined;
+  static const IconData disc = Icons.fiber_manual_record;
+  static const IconData error = Icons.error_outline;
+  static const IconData location = Icons.place_outlined;
+  static const IconData locationOff = Icons.location_off_outlined;
+  static const IconData raw = Icons.camera_outlined;
+  static const IconData shooting = Icons.camera_outlined;
+  static const IconData removableStorage = Icons.sd_storage_outlined;
+  static const IconData settings = Icons.settings_outlined;
+  static const IconData text = Icons.format_quote_outlined;
+  static const IconData tag = Icons.local_offer_outlined;
+  static const IconData tagOff = MdiIcons.tagOffOutline;
+
+  // actions
+  static const IconData addShortcut = Icons.add_to_home_screen_outlined;
+  static const IconData clear = Icons.clear_outlined;
+  static const IconData collapse = Icons.expand_less_outlined;
+  static const IconData createAlbum = Icons.add_circle_outline;
+  static const IconData debug = Icons.whatshot_outlined;
+  static const IconData delete = Icons.delete_outlined;
+  static const IconData expand = Icons.expand_more_outlined;
+  static const IconData flip = Icons.flip_outlined;
+  static const IconData favourite = Icons.favorite_border;
+  static const IconData favouriteActive = Icons.favorite;
+  static const IconData goUp = Icons.arrow_upward_outlined;
+  static const IconData group = Icons.group_work_outlined;
+  static const IconData info = Icons.info_outlined;
+  static const IconData layers = Icons.layers_outlined;
+  static const IconData openInNew = Icons.open_in_new_outlined;
+  static const IconData pin = Icons.push_pin_outlined;
+  static const IconData print = Icons.print_outlined;
+  static const IconData refresh = Icons.refresh_outlined;
+  static const IconData rename = Icons.title_outlined;
+  static const IconData rotateLeft = Icons.rotate_left_outlined;
+  static const IconData rotateRight = Icons.rotate_right_outlined;
+  static const IconData search = Icons.search_outlined;
+  static const IconData select = Icons.select_all_outlined;
+  static const IconData share = Icons.share_outlined;
+  static const IconData sort = Icons.sort_outlined;
+  static const IconData stats = Icons.pie_chart_outlined;
+  static const IconData zoomIn = Icons.add_outlined;
+  static const IconData zoomOut = Icons.remove_outlined;
+
+  // albums
+  static const IconData album = Icons.photo_album_outlined;
+  static const IconData cameraAlbum = Icons.photo_camera_outlined;
+  static const IconData downloadAlbum = Icons.file_download;
+  static const IconData screenshotAlbum = Icons.smartphone_outlined;
+
+  // thumbnail overlay
+  static const IconData animated = Icons.slideshow;
+  static const IconData play = Icons.play_circle_outline;
+  static const IconData selected = Icons.check_circle_outline;
+  static const IconData unselected = Icons.radio_button_unchecked;
+}

lib/utils/constants.dart

@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/painting.dart';
-import 'package:tuple/tuple.dart';
+import 'package:latlong/latlong.dart';
 
 class Constants {
   // as of Flutter v1.22.3, overflowing `Text` miscalculates height and some text (e.g. 'Å') is clipped
@@ -21,11 +21,23 @@ class Constants {
   static const String overlayUnknown = '—'; // em dash
   static const String infoUnknown = 'unknown';
 
-  static const pointNemo = Tuple2(-48.876667, -123.393333);
+  static final pointNemo = LatLng(-48.876667, -123.393333);
 
   static const int infoGroupMaxValueLength = 140;
 
   static const List<Dependency> androidDependencies = [
+    Dependency(
+      name: 'AndroidX Core-KTX',
+      license: 'Apache 2.0',
+      licenseUrl: 'https://android.googlesource.com/platform/frameworks/support/+/androidx-master-dev/LICENSE.txt',
+      sourceUrl: 'https://android.googlesource.com/platform/frameworks/support/+/androidx-master-dev/core/core-ktx',
+    ),
+    Dependency(
+      name: 'AndroidX Exifinterface',
+      license: 'Apache 2.0',
+      licenseUrl: 'https://android.googlesource.com/platform/frameworks/support/+/androidx-master-dev/LICENSE.txt',
+      sourceUrl: 'https://android.googlesource.com/platform/frameworks/support/+/androidx-master-dev/exifinterface/exifinterface',
+    ),
     Dependency(
       name: 'Android-TiffBitmapFactory',
       license: 'MIT',
@@ -96,7 +108,7 @@ class Constants {
       sourceUrl: 'https://github.com/Skylled/expansion_tile_card',
     ),
     Dependency(
-      name: 'FlutterFire',
+      name: 'FlutterFire (Core, Analytics, Crashlytics)',
       license: 'BSD 3-Clause',
       licenseUrl: 'https://github.com/FirebaseExtended/flutterfire/blob/master/LICENSE',
       sourceUrl: 'https://github.com/FirebaseExtended/flutterfire',
@@ -107,6 +119,12 @@ class Constants {
       licenseUrl: 'https://github.com/AndreHaueisen/flushbar/blob/master/LICENSE',
       sourceUrl: 'https://github.com/AndreHaueisen/flushbar',
     ),
+    Dependency(
+      name: 'Flutter Highlight',
+      license: 'MIT',
+      licenseUrl: 'https://github.com/git-touch/highlight/blob/master/LICENSE',
+      sourceUrl: 'https://github.com/git-touch/highlight',
+    ),
     Dependency(
       name: 'Flutter ijkplayer',
       license: 'MIT',
@@ -180,7 +198,7 @@ class Constants {
       sourceUrl: 'https://github.com/boyan01/overlay_support',
     ),
     Dependency(
-      name: 'Package info',
+      name: 'Package Info',
       license: 'BSD 3-Clause',
       licenseUrl: 'https://github.com/flutter/plugins/blob/master/packages/package_info/LICENSE',
       sourceUrl: 'https://github.com/flutter/plugins/tree/master/packages/package_info',
@@ -269,12 +287,6 @@ class Constants {
       licenseUrl: 'https://github.com/flutter/plugins/blob/master/packages/url_launcher/url_launcher/LICENSE',
       sourceUrl: 'https://github.com/flutter/plugins/blob/master/packages/url_launcher/url_launcher',
     ),
-    Dependency(
-      name: 'UUID',
-      license: 'MIT',
-      licenseUrl: 'https://github.com/Daegalus/dart-uuid/blob/master/LICENSE',
-      sourceUrl: 'https://github.com/Daegalus/dart-uuid',
-    ),
   ];
 }
 

lib/utils/debouncer.dart

@@ -0,0 +1,16 @@
+import 'dart:async';
+
+import 'package:flutter/foundation.dart';
+
+class Debouncer {
+  final Duration delay;
+
+  Timer _timer;
+
+  Debouncer({@required this.delay});
+
+  void call(Function action) {
+    _timer?.cancel();
+    _timer = Timer(delay, action);
+  }
+}

lib/utils/flutter_utils.dart

@@ -1,5 +0,0 @@
-import 'package:flutter/widgets.dart';
-
-extension ExtraContext on BuildContext {
-  String get currentRouteName => ModalRoute.of(this)?.settings?.name;
-}

lib/utils/geo_utils.dart

@@ -1,15 +1,12 @@
-import 'dart:math';
-
+import 'package:aves/utils/math_utils.dart';
 import 'package:intl/intl.dart';
-import 'package:tuple/tuple.dart';
+import 'package:latlong/latlong.dart';
 
 String _decimal2sexagesimal(final double degDecimal) {
-  double _round(final double value, {final int decimals = 6}) => (value * pow(10, decimals)).round() / pow(10, decimals);
-
   List<int> _split(final double value) {
     // NumberFormat is necessary to create digit after comma if the value
     // has no decimal point (only necessary for browser)
-    final tmp = NumberFormat('0.0#####').format(_round(value, decimals: 10)).split('.');
+    final tmp = NumberFormat('0.0#####').format(roundToPrecision(value, decimals: 10)).split('.');
     return <int>[
       int.parse(tmp[0]).abs(),
       int.parse(tmp[1]),
@@ -21,14 +18,14 @@ String _decimal2sexagesimal(final double degDecimal) {
   final min = _split(minDecimal)[0];
   final sec = (minDecimal - min) * 60;
 
-  return '$deg° $min′ ${_round(sec, decimals: 2).toStringAsFixed(2)}″';
+  return '$deg° $min′ ${roundToPrecision(sec, decimals: 2).toStringAsFixed(2)}″';
 }
 
 // return coordinates formatted as DMS, e.g. ['41° 24′ 12.2″ N', '2° 10′ 26.5″ E']
-List<String> toDMS(Tuple2<double, double> latLng) {
+List<String> toDMS(LatLng latLng) {
   if (latLng == null) return [];
-  final lat = latLng.item1;
-  final lng = latLng.item2;
+  final lat = latLng.latitude;
+  final lng = latLng.longitude;
   return [
     '${_decimal2sexagesimal(lat)} ${lat < 0 ? 'S' : 'N'}',
     '${_decimal2sexagesimal(lng)} ${lng < 0 ? 'W' : 'E'}',

lib/utils/math_utils.dart

@@ -1,11 +1,20 @@
 import 'dart:math';
 
-const double _piOver180 = pi / 180.0;
+import 'package:flutter/foundation.dart';
 
-final double log2 = log(2);
+final double _log2 = log(2);
+const double _piOver180 = pi / 180.0;
 
 double toDegrees(num radians) => radians / _piOver180;
 
 double toRadians(num degrees) => degrees * _piOver180;
 
-int highestPowerOf2(num x) => x < 1 ? 0 : pow(2, (log(x) / log2).floor());
+int highestPowerOf2(num x) => x < 1 ? 0 : pow(2, (log(x) / _log2).floor());
+
+double roundToPrecision(final double value, {@required final int decimals}) => (value * pow(10, decimals)).round() / pow(10, decimals);
+
+// e.g. x=12345, precision=3 should return 13000
+int ceilBy(num x, int precision) {
+  final factor = pow(10, precision);
+  return (x / factor).ceil() * factor;
+}

lib/utils/mime_utils.dart

@@ -0,0 +1,20 @@
+class MimeUtils {
+  static String displayType(String mime) {
+    switch (mime) {
+      case 'image/x-icon':
+        return 'ICO';
+      case 'image/vnd.adobe.photoshop':
+      case 'image/x-photoshop':
+        return 'PSD';
+      default:
+        final patterns = [
+          RegExp('.*/'), // remove type, keep subtype
+          RegExp('(X-|VND.(WAP.)?)'), // noisy prefixes
+          '+XML', // noisy suffix
+        ];
+        mime = mime.toUpperCase();
+        patterns.forEach((pattern) => mime = mime.replaceFirst(pattern, ''));
+        return mime;
+    }
+  }
+}

lib/widgets/about/about_page.dart

@@ -1,9 +1,8 @@
 import 'package:aves/flutter_version.dart';
 import 'package:aves/widgets/about/licenses.dart';
-import 'package:aves/widgets/common/aves_logo.dart';
-import 'package:aves/widgets/common/link_chip.dart';
+import 'package:aves/widgets/common/basic/link_chip.dart';
+import 'package:aves/widgets/common/identity/aves_logo.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter_staggered_animations/flutter_staggered_animations.dart';
 import 'package:package_info/package_info.dart';
 
 class AboutPage extends StatelessWidget {
@@ -16,24 +15,58 @@ class AboutPage extends StatelessWidget {
         title: Text('About'),
       ),
       body: SafeArea(
-        child: AnimationLimiter(
-          child: CustomScrollView(
-            slivers: [
-              SliverPadding(
-                padding: EdgeInsets.only(top: 16),
-                sliver: SliverList(
-                  delegate: SliverChildListDelegate(
-                    [
-                      AppReference(),
-                      SizedBox(height: 16),
-                      Divider(),
-                    ],
-                  ),
+        child: CustomScrollView(
+          slivers: [
+            SliverPadding(
+              padding: EdgeInsets.only(top: 16),
+              sliver: SliverList(
+                delegate: SliverChildListDelegate(
+                  [
+                    AppReference(),
+                    SizedBox(height: 16),
+                    Divider(),
+                    Padding(
+                      padding: EdgeInsets.symmetric(horizontal: 16),
+                      child: Column(
+                        crossAxisAlignment: CrossAxisAlignment.start,
+                        children: [
+                          ConstrainedBox(
+                            constraints: BoxConstraints(minHeight: 48),
+                            child: Align(
+                              alignment: AlignmentDirectional.centerStart,
+                              child: Text(
+                                'Credits',
+                                style: Theme.of(context).textTheme.headline6.copyWith(fontFamily: 'Concourse Caps'),
+                              ),
+                            ),
+                          ),
+                          RichText(
+                            text: TextSpan(
+                              children: [
+                                TextSpan(text: 'This app uses the font '),
+                                WidgetSpan(
+                                  child: LinkChip(
+                                    text: 'Concourse',
+                                    url: 'https://mbtype.com/fonts/concourse/',
+                                    textStyle: TextStyle(fontWeight: FontWeight.bold),
+                                  ),
+                                  alignment: PlaceholderAlignment.middle,
+                                ),
+                                TextSpan(text: ' for titles and the media information page.'),
+                              ],
+                            ),
+                          ),
+                          SizedBox(height: 16),
+                        ],
+                      ),
+                    ),
+                    Divider(),
+                  ],
                 ),
               ),
-              Licenses(),
-            ],
-          ),
+            ),
+            Licenses(),
+          ],
         ),
       ),
     );

lib/widgets/about/licenses.dart

@@ -1,11 +1,11 @@
+import 'package:aves/ref/brand_colors.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/utils/constants.dart';
-import 'package:aves/utils/durations.dart';
-import 'package:aves/widgets/common/icons.dart';
-import 'package:aves/widgets/common/link_chip.dart';
-import 'package:aves/widgets/common/menu_row.dart';
+import 'package:aves/widgets/common/basic/link_chip.dart';
+import 'package:aves/widgets/common/basic/menu_row.dart';
+import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
 import 'package:collection/collection.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter_staggered_animations/flutter_staggered_animations.dart';
 
 class Licenses extends StatefulWidget {
   @override
@@ -13,18 +13,20 @@ class Licenses extends StatefulWidget {
 }
 
 class _LicensesState extends State<Licenses> {
+  final ValueNotifier<String> _expandedNotifier = ValueNotifier(null);
   LicenseSort _sort = LicenseSort.name;
-  List<Dependency> _packages;
+  List<Dependency> _platform, _flutter;
 
   @override
   void initState() {
     super.initState();
-    _packages = [...Constants.androidDependencies, ...Constants.flutterPackages];
+    _platform = List.from(Constants.androidDependencies);
+    _flutter = List.from(Constants.flutterPackages);
     _sortPackages();
   }
 
   void _sortPackages() {
-    _packages.sort((a, b) {
+    int compare(Dependency a, Dependency b) {
       switch (_sort) {
         case LicenseSort.license:
           final c = compareAsciiUpperCase(a.license, b.license);
@@ -33,7 +35,10 @@ class _LicensesState extends State<Licenses> {
         default:
           return compareAsciiUpperCase(a.name, b.name);
       }
-    });
+    }
+
+    _platform.sort(compare);
+    _flutter.sort(compare);
   }
 
   @override
@@ -41,25 +46,40 @@ class _LicensesState extends State<Licenses> {
     return SliverPadding(
       padding: EdgeInsets.symmetric(horizontal: 8),
       sliver: SliverList(
-        delegate: SliverChildBuilderDelegate(
-          (context, index) {
-            if (index-- == 0) {
-              return _buildHeader();
-            }
-            final child = LicenseRow(_packages[index]);
-            return AnimationConfiguration.staggeredList(
-              position: index,
-              duration: Durations.staggeredAnimation,
-              delay: Durations.staggeredAnimationDelay,
-              child: SlideAnimation(
-                verticalOffset: 50.0,
-                child: FadeInAnimation(
-                  child: child,
+        delegate: SliverChildListDelegate(
+          [
+            _buildHeader(),
+            SizedBox(height: 16),
+            AvesExpansionTile(
+              title: 'Android Libraries',
+              color: BrandColors.android,
+              expandedNotifier: _expandedNotifier,
+              children: _platform.map((package) => LicenseRow(package)).toList(),
+            ),
+            AvesExpansionTile(
+              title: 'Flutter Packages',
+              color: BrandColors.flutter,
+              expandedNotifier: _expandedNotifier,
+              children: _flutter.map((package) => LicenseRow(package)).toList(),
+            ),
+            Center(
+              child: TextButton(
+                onPressed: () => Navigator.push(
+                  context,
+                  MaterialPageRoute(
+                    builder: (context) => Theme(
+                      data: Theme.of(context).copyWith(
+                        // as of Flutter v1.22.4, `cardColor` is used as a background color by `LicensePage`
+                        cardColor: Theme.of(context).scaffoldBackgroundColor,
+                      ),
+                      child: LicensePage(),
+                    ),
+                  ),
                 ),
+                child: Text('Show All Licenses'.toUpperCase()),
               ),
-            );
-          },
-          childCount: _packages.length + 1,
+            ),
+          ],
         ),
       ),
     );
@@ -122,7 +142,7 @@ class LicenseRow extends StatelessWidget {
     final subColor = bodyTextStyle.color.withOpacity(.6);
 
     return Padding(
-      padding: EdgeInsets.only(top: 16),
+      padding: EdgeInsets.symmetric(vertical: 8),
       child: Column(
         crossAxisAlignment: CrossAxisAlignment.start,
         children: [

lib/widgets/collection/app_bar.dart

@@ -1,23 +1,22 @@
 import 'dart:async';
 
 import 'package:aves/main.dart';
+import 'package:aves/model/actions/collection_actions.dart';
+import 'package:aves/model/actions/entry_actions.dart';
 import 'package:aves/model/settings/settings.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/model/source/collection_source.dart';
 import 'package:aves/model/source/enums.dart';
 import 'package:aves/services/app_shortcut_service.dart';
-import 'package:aves/utils/durations.dart';
-import 'package:aves/widgets/collection/collection_actions.dart';
+import 'package:aves/theme/durations.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/widgets/collection/entry_set_action_delegate.dart';
 import 'package:aves/widgets/collection/filter_bar.dart';
-import 'package:aves/widgets/common/action_delegates/add_shortcut_dialog.dart';
-import 'package:aves/widgets/common/action_delegates/selection_action_delegate.dart';
 import 'package:aves/widgets/common/app_bar_subtitle.dart';
 import 'package:aves/widgets/common/app_bar_title.dart';
-import 'package:aves/widgets/common/aves_selection_dialog.dart';
-import 'package:aves/widgets/common/data_providers/media_store_collection_provider.dart';
-import 'package:aves/widgets/common/entry_actions.dart';
-import 'package:aves/widgets/common/icons.dart';
-import 'package:aves/widgets/common/menu_row.dart';
+import 'package:aves/widgets/common/basic/menu_row.dart';
+import 'package:aves/widgets/dialogs/add_shortcut_dialog.dart';
+import 'package:aves/widgets/dialogs/aves_selection_dialog.dart';
 import 'package:aves/widgets/search/search_button.dart';
 import 'package:aves/widgets/search/search_delegate.dart';
 import 'package:aves/widgets/stats/stats.dart';
@@ -43,7 +42,7 @@ class CollectionAppBar extends StatefulWidget {
 
 class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerProviderStateMixin {
   final TextEditingController _searchFieldController = TextEditingController();
-  SelectionActionDelegate _actionDelegate;
+  EntrySetActionDelegate _actionDelegate;
   AnimationController _browseToSelectAnimation;
   Future<bool> _canAddShortcutsLoader;
 
@@ -56,7 +55,7 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
   @override
   void initState() {
     super.initState();
-    _actionDelegate = SelectionActionDelegate(
+    _actionDelegate = EntrySetActionDelegate(
       collection: collection,
     );
     _browseToSelectAnimation = AnimationController(
@@ -259,7 +258,10 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
                 ]
               ];
             },
-            onSelected: _onCollectionActionSelected,
+            onSelected: (action) {
+              // wait for the popup menu to hide before proceeding with the action
+              Future.delayed(Durations.popupMenuAnimation * timeDilation, () => _onCollectionActionSelected(action));
+            },
           );
         },
       ),
@@ -279,9 +281,7 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
     widget.appBarHeightNotifier.value = kToolbarHeight + (hasFilters ? FilterBar.preferredHeight : 0);
   }
 
-  void _onCollectionActionSelected(CollectionAction action) async {
-    // wait for the popup menu to hide before proceeding with the action
-    await Future.delayed(Durations.popupMenuAnimation * timeDilation);
+  Future<void> _onCollectionActionSelected(CollectionAction action) async {
     switch (action) {
       case CollectionAction.copy:
       case CollectionAction.move:
@@ -289,10 +289,7 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
         _actionDelegate.onCollectionActionSelected(context, action);
         break;
       case CollectionAction.refresh:
-        if (source is MediaStoreSource) {
-          source.clearEntries();
-          unawaited((source as MediaStoreSource).refresh());
-        }
+        unawaited(source.refresh());
         break;
       case CollectionAction.select:
         collection.select();
@@ -377,7 +374,8 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
       MaterialPageRoute(
         settings: RouteSettings(name: StatsPage.routeName),
         builder: (context) => StatsPage(
-          collection: collection,
+          source: source,
+          parentCollection: collection,
         ),
       ),
     );

lib/widgets/collection/collection_page.dart

@@ -1,7 +1,7 @@
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/widgets/collection/thumbnail_collection.dart';
-import 'package:aves/widgets/common/data_providers/media_query_data_provider.dart';
-import 'package:aves/widgets/common/double_back_pop.dart';
+import 'package:aves/widgets/common/behaviour/double_back_pop.dart';
+import 'package:aves/widgets/common/providers/media_query_data_provider.dart';
 import 'package:aves/widgets/drawer/app_drawer.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';

lib/widgets/collection/entry_set_action_delegate.dart

@@ -1,34 +1,30 @@
 import 'dart:async';
 
-import 'package:aves/model/filters/album.dart';
-import 'package:aves/model/settings/settings.dart';
+import 'package:aves/model/actions/collection_actions.dart';
+import 'package:aves/model/actions/entry_actions.dart';
+import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/model/source/collection_source.dart';
-import 'package:aves/model/source/enums.dart';
 import 'package:aves/services/android_app_service.dart';
 import 'package:aves/services/image_file_service.dart';
-import 'package:aves/widgets/collection/collection_actions.dart';
-import 'package:aves/widgets/collection/empty.dart';
-import 'package:aves/widgets/common/action_delegates/create_album_dialog.dart';
-import 'package:aves/widgets/common/action_delegates/feedback.dart';
-import 'package:aves/widgets/common/action_delegates/permission_aware.dart';
-import 'package:aves/widgets/common/aves_dialog.dart';
-import 'package:aves/widgets/common/entry_actions.dart';
-import 'package:aves/widgets/common/icons.dart';
-import 'package:aves/widgets/filter_grids/albums_page.dart';
-import 'package:aves/widgets/filter_grids/common/chip_actions.dart';
-import 'package:aves/widgets/filter_grids/common/chip_set_action_delegate.dart';
-import 'package:aves/widgets/filter_grids/common/filter_grid_page.dart';
+import 'package:aves/widgets/common/action_mixins/feedback.dart';
+import 'package:aves/widgets/common/action_mixins/permission_aware.dart';
+import 'package:aves/widgets/common/action_mixins/size_aware.dart';
+import 'package:aves/widgets/dialogs/aves_dialog.dart';
+import 'package:aves/widgets/filter_grids/album_pick.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:intl/intl.dart';
-import 'package:provider/provider.dart';
 
-class SelectionActionDelegate with FeedbackMixin, PermissionAwareMixin {
+class EntrySetActionDelegate with FeedbackMixin, PermissionAwareMixin, SizeAwareMixin {
   final CollectionLens collection;
 
-  SelectionActionDelegate({
+  CollectionSource get source => collection.source;
+
+  Set<ImageEntry> get selection => collection.selection;
+
+  EntrySetActionDelegate({
     @required this.collection,
   });
 
@@ -38,7 +34,9 @@ class SelectionActionDelegate with FeedbackMixin, PermissionAwareMixin {
         _showDeleteDialog(context);
         break;
       case EntryAction.share:
-        AndroidAppService.share(collection.selection);
+        AndroidAppService.share(selection).then((success) {
+          if (!success) showNoMatchingAppDialog(context);
+        });
         break;
       default:
         break;
@@ -54,7 +52,9 @@ class SelectionActionDelegate with FeedbackMixin, PermissionAwareMixin {
         _moveSelection(context, copy: false);
         break;
       case CollectionAction.refreshMetadata:
-        _refreshSelectionMetadata();
+        source.refreshMetadata(selection);
+        collection.clearSelection();
+        collection.browse();
         break;
       default:
         break;
@@ -62,60 +62,20 @@ class SelectionActionDelegate with FeedbackMixin, PermissionAwareMixin {
   }
 
   Future<void> _moveSelection(BuildContext context, {@required bool copy}) async {
-    final source = collection.source;
-    final chipSetActionDelegate = AlbumChipSetActionDelegate(source: source);
     final destinationAlbum = await Navigator.push(
       context,
       MaterialPageRoute<String>(
-        builder: (context) {
-          return Selector<Settings, ChipSortFactor>(
-            selector: (context, s) => s.albumSortFactor,
-            builder: (context, sortFactor, child) {
-              return FilterGridPage(
-                source: source,
-                appBar: SliverAppBar(
-                  leading: BackButton(),
-                  title: Text(copy ? 'Copy to Album' : 'Move to Album'),
-                  actions: [
-                    IconButton(
-                      icon: Icon(AIcons.createAlbum),
-                      onPressed: () async {
-                        final newAlbum = await showDialog<String>(
-                          context: context,
-                          builder: (context) => CreateAlbumDialog(),
-                        );
-                        if (newAlbum != null && newAlbum.isNotEmpty) {
-                          Navigator.pop<String>(context, newAlbum);
-                        }
-                      },
-                      tooltip: 'Create album',
-                    ),
-                    IconButton(
-                      icon: Icon(AIcons.sort),
-                      onPressed: () => chipSetActionDelegate.onActionSelected(context, ChipSetAction.sort),
-                    ),
-                  ],
-                  floating: true,
-                ),
-                filterEntries: AlbumListPage.getAlbumEntries(source),
-                filterBuilder: (s) => AlbumFilter(s, source.getUniqueAlbumName(s)),
-                emptyBuilder: () => EmptyContent(
-                  icon: AIcons.album,
-                  text: 'No albums',
-                ),
-                onTap: (filter) => Navigator.pop<String>(context, (filter as AlbumFilter)?.album),
-              );
-            },
-          );
-        },
+        settings: RouteSettings(name: AlbumPickPage.routeName),
+        builder: (context) => AlbumPickPage(source: source, copy: copy),
       ),
     );
     if (destinationAlbum == null || destinationAlbum.isEmpty) return;
     if (!await checkStoragePermissionForAlbums(context, {destinationAlbum})) return;
 
-    final selection = collection.selection.toList();
     if (!await checkStoragePermission(context, selection)) return;
 
+    if (!await checkFreeSpaceForMove(context, selection, destinationAlbum, copy)) return;
+
     showOpReport<MoveOpEvent>(
       context: context,
       selection: selection,
@@ -143,24 +103,14 @@ class SelectionActionDelegate with FeedbackMixin, PermissionAwareMixin {
     );
   }
 
-  Future<void> _refreshSelectionMetadata() async {
-    collection.selection.forEach((entry) => entry.clearMetadata());
-    final source = collection.source;
-    source.stateNotifier.value = SourceState.cataloguing;
-    await source.catalogEntries();
-    source.stateNotifier.value = SourceState.locating;
-    await source.locateEntries();
-    source.stateNotifier.value = SourceState.ready;
-  }
-
   Future<void> _showDeleteDialog(BuildContext context) async {
-    final selection = collection.selection.toList();
     final count = selection.length;
 
     final confirmed = await showDialog<bool>(
       context: context,
       builder: (context) {
         return AvesDialog(
+          context: context,
           content: Text('Are you sure you want to delete ${Intl.plural(count, one: 'this item', other: 'these $count items')}?'),
           actions: [
             TextButton(
@@ -192,7 +142,7 @@ class SelectionActionDelegate with FeedbackMixin, PermissionAwareMixin {
           showFeedback(context, 'Failed to delete ${Intl.plural(count, one: '$count item', other: '$count items')}');
         }
         if (deletedCount > 0) {
-          collection.source.removeEntries(selection.where((e) => deletedUris.contains(e.uri)).toList());
+          source.removeEntries(selection.where((e) => deletedUris.contains(e.uri)).toList());
         }
         collection.clearSelection();
         collection.browse();

lib/widgets/collection/filter_bar.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/filters/filters.dart';
-import 'package:aves/utils/durations.dart';
-import 'package:aves/widgets/common/aves_filter_chip.dart';
+import 'package:aves/theme/durations.dart';
+import 'package:aves/widgets/common/identity/aves_filter_chip.dart';
 import 'package:flutter/material.dart';
 
 class FilterBar extends StatefulWidget implements PreferredSizeWidget {

lib/widgets/collection/grid/header_album.dart

@@ -1,6 +1,7 @@
+import 'package:aves/theme/icons.dart';
 import 'package:aves/utils/android_file_utils.dart';
 import 'package:aves/widgets/collection/grid/header_generic.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/widgets/common/identity/aves_icons.dart';
 import 'package:flutter/material.dart';
 
 class AlbumSectionHeader extends StatelessWidget {

lib/widgets/collection/grid/header_generic.dart

@@ -3,12 +3,12 @@ import 'dart:math';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/model/source/collection_source.dart';
 import 'package:aves/model/source/enums.dart';
+import 'package:aves/theme/durations.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/utils/android_file_utils.dart';
 import 'package:aves/utils/constants.dart';
-import 'package:aves/utils/durations.dart';
 import 'package:aves/widgets/collection/grid/header_album.dart';
 import 'package:aves/widgets/collection/grid/header_date.dart';
-import 'package:aves/widgets/common/icons.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 import 'package:provider/provider.dart';

lib/widgets/collection/grid/list_section_layout.dart

@@ -3,7 +3,7 @@ import 'dart:math';
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/widgets/collection/grid/header_generic.dart';
-import 'package:aves/widgets/collection/grid/tile_extent_manager.dart';
+import 'package:aves/widgets/collection/thumbnail_collection.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
@@ -22,7 +22,7 @@ class SectionedListLayoutProvider extends StatelessWidget {
     @required this.thumbnailBuilder,
     @required this.child,
   })  : assert(scrollableWidth != 0),
-        columnCount = max((scrollableWidth / tileExtent).round(), TileExtentManager.columnCountMin);
+        columnCount = max((scrollableWidth / tileExtent).round(), ThumbnailCollection.columnCountMin);
 
   @override
   Widget build(BuildContext context) {

lib/widgets/collection/grid/list_sliver.dart

@@ -4,8 +4,9 @@ import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/services/viewer_service.dart';
 import 'package:aves/widgets/collection/grid/list_known_extent.dart';
 import 'package:aves/widgets/collection/grid/list_section_layout.dart';
+import 'package:aves/widgets/common/scaling.dart';
 import 'package:aves/widgets/collection/thumbnail/decorated.dart';
-import 'package:aves/widgets/common/routes.dart';
+import 'package:aves/widgets/common/behaviour/routes.dart';
 import 'package:aves/widgets/fullscreen/fullscreen_page.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
@@ -70,7 +71,7 @@ class GridThumbnail extends StatelessWidget {
         }
       },
       child: MetaData(
-        metaData: ThumbnailMetadata(entry),
+        metaData: ScalerMetadata(entry),
         child: DecoratedThumbnail(
           entry: entry,
           extent: tileExtent,
@@ -94,10 +95,3 @@ class GridThumbnail extends StatelessWidget {
     );
   }
 }
-
-// metadata to identify entry from RenderObject hit test during collection scaling
-class ThumbnailMetadata {
-  final ImageEntry entry;
-
-  const ThumbnailMetadata(this.entry);
-}

lib/widgets/collection/grid/tile_extent_manager.dart

@@ -1,41 +0,0 @@
-import 'dart:math';
-
-import 'package:aves/model/settings/settings.dart';
-import 'package:flutter/widgets.dart';
-
-class TileExtentManager {
-  static const int columnCountMin = 2;
-  static const int columnCountDefault = 4;
-  static const double tileExtentMin = 46.0;
-  static const screenDimensionMin = tileExtentMin * columnCountMin;
-
-  static double applyTileExtent(Size mqSize, double mqHorizontalPadding, ValueNotifier<double> extentNotifier, {double newExtent}) {
-    // sanitize screen size (useful when reloading while screen is off, reporting a 0,0 size)
-    mqSize = Size(max(mqSize.width, screenDimensionMin), max(mqSize.height, screenDimensionMin));
-
-    final availableWidth = mqSize.width - mqHorizontalPadding;
-    var numColumns;
-    if ((newExtent ?? 0) == 0) {
-      newExtent = extentNotifier.value;
-    }
-    if ((newExtent ?? 0) == 0) {
-      newExtent = settings.collectionTileExtent;
-    }
-    if ((newExtent ?? 0) == 0) {
-      numColumns = columnCountDefault;
-    } else {
-      newExtent = newExtent.clamp(tileExtentMin, extentMaxForSize(mqSize));
-      numColumns = max(columnCountMin, (availableWidth / newExtent).round());
-    }
-    newExtent = availableWidth / numColumns;
-    if (extentNotifier.value != newExtent) {
-      settings.collectionTileExtent = newExtent;
-      extentNotifier.value = newExtent;
-    }
-    return newExtent;
-  }
-
-  static double extentMaxForSize(Size mqSize) {
-    return mqSize.shortestSide / columnCountMin;
-  }
-}

lib/widgets/collection/thumbnail/decorated.dart

@@ -10,7 +10,7 @@ class DecoratedThumbnail extends StatelessWidget {
   final double extent;
   final CollectionLens collection;
   final ValueNotifier<bool> isScrollingNotifier;
-  final bool showOverlay;
+  final bool selectable, highlightable;
   final Object heroTag;
 
   static final Color borderColor = Colors.grey.shade700;
@@ -22,7 +22,8 @@ class DecoratedThumbnail extends StatelessWidget {
     @required this.extent,
     this.collection,
     this.isScrollingNotifier,
-    this.showOverlay = true,
+    this.selectable = true,
+    this.highlightable = true,
   })  : heroTag = collection?.heroTag(entry),
         super(key: key);
 
@@ -40,29 +41,32 @@ class DecoratedThumbnail extends StatelessWidget {
             isScrollingNotifier: isScrollingNotifier,
             heroTag: heroTag,
           );
-    if (showOverlay) {
-      child = Stack(
-        children: [
-          child,
-          Positioned(
-            bottom: 0,
-            left: 0,
-            child: ThumbnailEntryOverlay(
-              entry: entry,
-              extent: extent,
-            ),
+
+    child = Stack(
+      fit: StackFit.passthrough,
+      children: [
+        child,
+        Positioned(
+          bottom: 0,
+          left: 0,
+          child: ThumbnailEntryOverlay(
+            entry: entry,
+            extent: extent,
           ),
+        ),
+        if (selectable)
           ThumbnailSelectionOverlay(
             entry: entry,
             extent: extent,
           ),
+        if (highlightable)
           ThumbnailHighlightOverlay(
-            highlightedStream: collection.highlightStream.map((highlighted) => highlighted == entry),
+            entry: entry,
             extent: extent,
           ),
-        ],
-      );
-    }
+      ],
+    );
+
     return Container(
       foregroundDecoration: BoxDecoration(
         border: Border.all(

lib/widgets/collection/thumbnail/error.dart

@@ -1,5 +1,5 @@
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/model/mime_types.dart';
+import 'package:aves/utils/mime_utils.dart';
 import 'package:flutter/material.dart';
 
 class ErrorThumbnail extends StatelessWidget {
@@ -15,12 +15,14 @@ class ErrorThumbnail extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return Center(
+    return Container(
+      alignment: Alignment.center,
+      color: Colors.black,
       child: Tooltip(
         message: tooltip,
         preferBelow: false,
         child: Text(
-          MimeTypes.displayType(entry.mimeType),
+          MimeUtils.displayType(entry.mimeType),
           style: TextStyle(
             color: Colors.blueGrey,
             fontSize: extent / 5,

lib/widgets/collection/thumbnail/overlay.dart

@@ -1,12 +1,14 @@
 import 'dart:math';
 
+import 'package:aves/model/highlight.dart';
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/settings/settings.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/model/source/enums.dart';
-import 'package:aves/utils/durations.dart';
+import 'package:aves/theme/durations.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/widgets/common/fx/sweeper.dart';
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/widgets/common/identity/aves_icons.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:tuple/tuple.dart';
@@ -115,13 +117,13 @@ class ThumbnailSelectionOverlay extends StatelessWidget {
 }
 
 class ThumbnailHighlightOverlay extends StatefulWidget {
+  final ImageEntry entry;
   final double extent;
-  final Stream<bool> highlightedStream;
 
   const ThumbnailHighlightOverlay({
     Key key,
+    @required this.entry,
     @required this.extent,
-    @required this.highlightedStream,
   }) : super(key: key);
 
   @override
@@ -131,27 +133,25 @@ class ThumbnailHighlightOverlay extends StatefulWidget {
 class _ThumbnailHighlightOverlayState extends State<ThumbnailHighlightOverlay> {
   final ValueNotifier<bool> _highlightedNotifier = ValueNotifier(false);
 
+  ImageEntry get entry => widget.entry;
+
   @override
   Widget build(BuildContext context) {
-    return StreamBuilder<bool>(
-      stream: widget.highlightedStream,
-      builder: (context, snapshot) {
-        _highlightedNotifier.value = snapshot.hasData && snapshot.data;
-        return Sweeper(
-          builder: (context) => Container(
-            decoration: BoxDecoration(
-              border: Border.all(
-                color: Theme.of(context).accentColor,
-                width: widget.extent * .1,
-              ),
-            ),
+    final highlightInfo = context.watch<HighlightInfo>();
+    _highlightedNotifier.value = highlightInfo.contains(entry);
+    return Sweeper(
+      builder: (context) => Container(
+        decoration: BoxDecoration(
+          border: Border.all(
+            color: Theme.of(context).accentColor,
+            width: widget.extent * .1,
           ),
-          toggledNotifier: _highlightedNotifier,
-          startAngle: pi * -3 / 4,
-          centerSweep: false,
-          onSweepEnd: () => _highlightedNotifier.value = false,
-        );
-      },
+        ),
+      ),
+      toggledNotifier: _highlightedNotifier,
+      startAngle: pi * -3 / 4,
+      centerSweep: false,
+      onSweepEnd: () => highlightInfo.remove(entry),
     );
   }
 }

lib/widgets/collection/thumbnail/raster.dart

@@ -1,11 +1,11 @@
 import 'dart:math';
 
+import 'package:aves/image_providers/thumbnail_provider.dart';
+import 'package:aves/image_providers/uri_image_provider.dart';
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/utils/durations.dart';
+import 'package:aves/theme/durations.dart';
 import 'package:aves/widgets/collection/thumbnail/error.dart';
-import 'package:aves/widgets/common/image_providers/thumbnail_provider.dart';
-import 'package:aves/widgets/common/image_providers/uri_image_provider.dart';
-import 'package:aves/widgets/common/transition_image.dart';
+import 'package:aves/widgets/common/fx/transition_image.dart';
 import 'package:flutter/material.dart';
 
 class ThumbnailRasterImage extends StatefulWidget {
@@ -98,16 +98,13 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
   @override
   Widget build(BuildContext context) {
     if (!entry.canDecode) {
-      return ErrorThumbnail(
-        entry: entry,
-        extent: extent,
-        tooltip: '${entry.mimeType} not supported',
-      );
+      return _buildError(context, '${entry.mimeType} not supported', null);
     }
 
     final fastImage = Image(
       key: ValueKey('LQ'),
       image: _fastThumbnailProvider,
+      errorBuilder: _buildError,
       width: extent,
       height: extent,
       fit: BoxFit.cover,
@@ -137,11 +134,7 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
                 child: frame == null ? fastImage : child,
               );
             },
-            errorBuilder: (context, error, stackTrace) => ErrorThumbnail(
-              entry: entry,
-              extent: extent,
-              tooltip: error.toString(),
-            ),
+            errorBuilder: _buildError,
             width: extent,
             height: extent,
             fit: BoxFit.cover,
@@ -173,6 +166,12 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
           );
   }
 
+  Widget _buildError(BuildContext context, Object error, StackTrace stackTrace) => ErrorThumbnail(
+        entry: entry,
+        extent: extent,
+        tooltip: error.toString(),
+      );
+
   // when the entry image itself changed (e.g. after rotation)
   void _onImageChanged() async {
     // rebuild to refresh the thumbnails

lib/widgets/collection/thumbnail/vector.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/settings/settings.dart';
-import 'package:aves/widgets/common/image_providers/uri_picture_provider.dart';
+import 'package:aves/image_providers/uri_picture_provider.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_svg/flutter_svg.dart';
 import 'package:provider/provider.dart';
@@ -32,10 +32,10 @@ class ThumbnailVectorImage extends StatelessWidget {
             UriPicture(
               uri: entry.uri,
               mimeType: entry.mimeType,
+              colorFilter: colorFilter,
             ),
             width: extent,
             height: extent,
-            colorFilter: colorFilter,
           );
         },
       ),

lib/widgets/collection/thumbnail_collection.dart

@@ -2,24 +2,28 @@ import 'dart:async';
 
 import 'package:aves/model/filters/favourite.dart';
 import 'package:aves/model/filters/mime.dart';
-import 'package:aves/model/mime_types.dart';
+import 'package:aves/model/highlight.dart';
+import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/model/source/collection_source.dart';
-import 'package:aves/utils/durations.dart';
+import 'package:aves/ref/mime_types.dart';
+import 'package:aves/theme/durations.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/widgets/collection/app_bar.dart';
 import 'package:aves/widgets/collection/empty.dart';
 import 'package:aves/widgets/collection/grid/list_section_layout.dart';
 import 'package:aves/widgets/collection/grid/list_sliver.dart';
-import 'package:aves/widgets/collection/grid/scaling.dart';
-import 'package:aves/widgets/collection/grid/tile_extent_manager.dart';
-import 'package:aves/widgets/common/icons.dart';
-import 'package:aves/widgets/common/scroll_thumb.dart';
-import 'package:aves/widgets/common/sloppy_scroll_physics.dart';
+import 'package:aves/widgets/collection/thumbnail/decorated.dart';
+import 'package:aves/widgets/common/behaviour/routes.dart';
+import 'package:aves/widgets/common/behaviour/sloppy_scroll_physics.dart';
+import 'package:aves/widgets/common/identity/scroll_thumb.dart';
+import 'package:aves/widgets/common/providers/highlight_info_provider.dart';
+import 'package:aves/widgets/common/scaling.dart';
+import 'package:aves/widgets/common/tile_extent_manager.dart';
 import 'package:draggable_scrollbar/draggable_scrollbar.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 import 'package:provider/provider.dart';
-import 'package:tuple/tuple.dart';
 
 class ThumbnailCollection extends StatelessWidget {
   final ValueNotifier<double> _appBarHeightNotifier = ValueNotifier(0);
@@ -27,67 +31,88 @@ class ThumbnailCollection extends StatelessWidget {
   final ValueNotifier<bool> _isScrollingNotifier = ValueNotifier(false);
   final GlobalKey _scrollableKey = GlobalKey();
 
+  static const columnCountMin = 2;
+  static const columnCountDefault = 4;
+  static const extentMin = 46.0;
+
   @override
   Widget build(BuildContext context) {
-    return SafeArea(
-      child: Selector<MediaQueryData, Tuple2<Size, double>>(
-        selector: (context, mq) => Tuple2(mq.size, mq.padding.horizontal),
-        builder: (context, mq, child) {
-          final mqSize = mq.item1;
-          final mqHorizontalPadding = mq.item2;
+    return HighlightInfoProvider(
+      child: SafeArea(
+        child: LayoutBuilder(
+          builder: (context, constraints) {
+            final viewportSize = constraints.biggest;
+            assert(viewportSize.isFinite, 'Cannot layout collection with unbounded constraints.');
+            if (viewportSize.isEmpty) return SizedBox.shrink();
 
-          if (mqSize.isEmpty) return SizedBox.shrink();
+            final tileExtentManager = TileExtentManager(
+              settingsRouteKey: context.currentRouteName,
+              columnCountMin: columnCountMin,
+              columnCountDefault: columnCountDefault,
+              extentMin: extentMin,
+              extentNotifier: _tileExtentNotifier,
+              spacing: 0,
+            )..applyTileExtent(viewportSize: viewportSize);
+            final cacheExtent = tileExtentManager.getEffectiveExtentMax(viewportSize) * 2;
 
-          TileExtentManager.applyTileExtent(mqSize, mqHorizontalPadding, _tileExtentNotifier);
-          final cacheExtent = TileExtentManager.extentMaxForSize(mqSize) * 2;
-
-          // do not replace by Provider.of<CollectionLens>
-          // so that view updates on collection filter changes
-          return Consumer<CollectionLens>(
-            builder: (context, collection, child) {
-              final scrollView = CollectionScrollView(
-                scrollableKey: _scrollableKey,
-                collection: collection,
-                appBar: CollectionAppBar(
-                  appBarHeightNotifier: _appBarHeightNotifier,
+            // do not replace by Provider.of<CollectionLens>
+            // so that view updates on collection filter changes
+            return Consumer<CollectionLens>(
+              builder: (context, collection, child) {
+                final scrollView = CollectionScrollView(
+                  scrollableKey: _scrollableKey,
                   collection: collection,
-                ),
-                appBarHeightNotifier: _appBarHeightNotifier,
-                isScrollingNotifier: _isScrollingNotifier,
-                scrollController: PrimaryScrollController.of(context),
-                cacheExtent: cacheExtent,
-              );
-
-              final scaler = GridScaleGestureDetector(
-                scrollableKey: _scrollableKey,
-                appBarHeightNotifier: _appBarHeightNotifier,
-                extentNotifier: _tileExtentNotifier,
-                mqSize: mqSize,
-                mqHorizontalPadding: mqHorizontalPadding,
-                onScaled: collection.highlight,
-                child: scrollView,
-              );
-
-              final sectionedListLayoutProvider = ValueListenableBuilder<double>(
-                valueListenable: _tileExtentNotifier,
-                builder: (context, tileExtent, child) => SectionedListLayoutProvider(
-                  collection: collection,
-                  scrollableWidth: mqSize.width - mqHorizontalPadding,
-                  tileExtent: tileExtent,
-                  thumbnailBuilder: (entry) => GridThumbnail(
-                    key: ValueKey(entry.contentId),
+                  appBar: CollectionAppBar(
+                    appBarHeightNotifier: _appBarHeightNotifier,
                     collection: collection,
-                    entry: entry,
-                    tileExtent: tileExtent,
-                    isScrollingNotifier: _isScrollingNotifier,
                   ),
-                  child: scaler,
-                ),
-              );
-              return sectionedListLayoutProvider;
-            },
-          );
-        },
+                  appBarHeightNotifier: _appBarHeightNotifier,
+                  isScrollingNotifier: _isScrollingNotifier,
+                  scrollController: PrimaryScrollController.of(context),
+                  cacheExtent: cacheExtent,
+                );
+
+                final scaler = GridScaleGestureDetector<ImageEntry>(
+                  tileExtentManager: tileExtentManager,
+                  scrollableKey: _scrollableKey,
+                  appBarHeightNotifier: _appBarHeightNotifier,
+                  viewportSize: viewportSize,
+                  showScaledGrid: true,
+                  scaledBuilder: (entry, extent) => DecoratedThumbnail(
+                    entry: entry,
+                    extent: extent,
+                    selectable: false,
+                    highlightable: false,
+                  ),
+                  getScaledItemTileRect: (context, entry) {
+                    final sectionedListLayout = Provider.of<SectionedListLayout>(context, listen: false);
+                    return sectionedListLayout.getTileRect(entry) ?? Rect.zero;
+                  },
+                  onScaled: (entry) => Provider.of<HighlightInfo>(context, listen: false).add(entry),
+                  child: scrollView,
+                );
+
+                final sectionedListLayoutProvider = ValueListenableBuilder<double>(
+                  valueListenable: _tileExtentNotifier,
+                  builder: (context, tileExtent, child) => SectionedListLayoutProvider(
+                    collection: collection,
+                    scrollableWidth: viewportSize.width,
+                    tileExtent: tileExtent,
+                    thumbnailBuilder: (entry) => GridThumbnail(
+                      key: ValueKey(entry.contentId),
+                      collection: collection,
+                      entry: entry,
+                      tileExtent: tileExtent,
+                      isScrollingNotifier: _isScrollingNotifier,
+                    ),
+                    child: scaler,
+                  ),
+                );
+                return sectionedListLayoutProvider;
+              },
+            );
+          },
+        ),
       ),
     );
   }

lib/widgets/common/action_mixins/feedback.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/services/image_file_service.dart';
-import 'package:aves/utils/durations.dart';
+import 'package:aves/theme/durations.dart';
 import 'package:flushbar/flushbar.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/scheduler.dart';
@@ -31,7 +31,7 @@ mixin FeedbackMixin {
 
   void showOpReport<T extends ImageOpEvent>({
     @required BuildContext context,
-    @required List<ImageEntry> selection,
+    @required Set<ImageEntry> selection,
     @required Stream<T> opStream,
     @required void Function(Set<T> processed) onDone,
   }) {

lib/widgets/common/action_mixins/permission_aware.dart

@@ -1,11 +1,10 @@
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/services/android_file_service.dart';
+import 'package:aves/widgets/dialogs/aves_dialog.dart';
 import 'package:flutter/material.dart';
 
-import '../aves_dialog.dart';
-
 mixin PermissionAwareMixin {
-  Future<bool> checkStoragePermission(BuildContext context, Iterable<ImageEntry> entries) {
+  Future<bool> checkStoragePermission(BuildContext context, Set<ImageEntry> entries) {
     return checkStoragePermissionForAlbums(context, entries.where((e) => e.path != null).map((e) => e.directory).toSet());
   }
 
@@ -25,6 +24,7 @@ mixin PermissionAwareMixin {
         context: context,
         builder: (context) {
           return AvesDialog(
+            context: context,
             title: 'Storage Volume Access',
             content: Text('Please select the $dirDisplayName directory of “$volumeDescription” in the next screen, so that this app can access it and complete your request.'),
             actions: [

lib/widgets/common/action_mixins/size_aware.dart

@@ -0,0 +1,52 @@
+import 'dart:async';
+import 'dart:math';
+
+import 'package:aves/model/image_entry.dart';
+import 'package:aves/services/android_file_service.dart';
+import 'package:aves/utils/android_file_utils.dart';
+import 'package:aves/utils/file_utils.dart';
+import 'package:aves/widgets/dialogs/aves_dialog.dart';
+import 'package:collection/collection.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+mixin SizeAwareMixin {
+  Future<bool> checkFreeSpaceForMove(BuildContext context, Set<ImageEntry> selection, String destinationAlbum, bool copy) async {
+    final destinationVolume = androidFileUtils.getStorageVolume(destinationAlbum);
+    final free = await AndroidFileService.getFreeSpace(destinationVolume);
+    int needed;
+    int sumSize(sum, entry) => sum + entry.sizeBytes;
+    if (copy) {
+      needed = selection.fold(0, sumSize);
+    } else {
+      // when moving, we only need space for the entries that are not already on the destination volume
+      final byVolume = groupBy<ImageEntry, StorageVolume>(selection, (entry) => androidFileUtils.getStorageVolume(entry.path));
+      final otherVolumes = byVolume.keys.where((volume) => volume != destinationVolume);
+      final fromOtherVolumes = otherVolumes.fold<int>(0, (sum, volume) => sum + byVolume[volume].fold(0, sumSize));
+      // and we need at least as much space as the largest entry because individual entries are copied then deleted
+      final largestSingle = selection.fold<int>(0, (largest, entry) => max(largest, entry.sizeBytes));
+      needed = max(fromOtherVolumes, largestSingle);
+    }
+
+    final hasEnoughSpace = needed < free;
+    if (!hasEnoughSpace) {
+      await showDialog(
+        context: context,
+        builder: (context) {
+          return AvesDialog(
+            context: context,
+            title: 'Not Enough Space',
+            content: Text('This operation needs ${formatFilesize(needed)} of free space on “${destinationVolume.description}” to complete, but there is only ${formatFilesize(free)} left.'),
+            actions: [
+              TextButton(
+                onPressed: () => Navigator.pop(context),
+                child: Text('OK'.toUpperCase()),
+              ),
+            ],
+          );
+        },
+      );
+    }
+    return hasEnoughSpace;
+  }
+}

lib/widgets/common/app_bar_subtitle.dart

@@ -1,5 +1,5 @@
 import 'package:aves/model/source/collection_source.dart';
-import 'package:aves/utils/durations.dart';
+import 'package:aves/theme/durations.dart';
 import 'package:flutter/material.dart';
 
 class SourceStateAwareAppBarTitle extends StatelessWidget {

lib/widgets/common/aves_dialog.dart

@@ -1,76 +0,0 @@
-import 'package:flutter/material.dart';
-import 'package:flutter/widgets.dart';
-
-class AvesDialog extends AlertDialog {
-  static const contentHorizontalPadding = EdgeInsets.symmetric(horizontal: 24);
-
-  AvesDialog({
-    String title,
-    ScrollController scrollController,
-    List<Widget> scrollableContent,
-    Widget content,
-    @required List<Widget> actions,
-  })  : assert((scrollableContent != null) ^ (content != null)),
-        super(
-          title: title != null ? DialogTitle(title: title) : null,
-          titlePadding: EdgeInsets.zero,
-          // the `scrollable` flag of `AlertDialog` makes it
-          // scroll both the title and the content together,
-          // and overflow feedback ignores the dialog shape,
-          // so we restrict scrolling to the content instead
-          content: scrollableContent != null
-              ? Builder(
-                  builder: (context) => Container(
-                    // workaround because the dialog tries
-                    // to size itself to the content intrinsic size,
-                    // but the `ListView` viewport does not have one
-                    width: 1,
-                    child: DecoratedBox(
-                      decoration: BoxDecoration(
-                        border: Border(
-                          bottom: Divider.createBorderSide(context, width: 1),
-                        ),
-                      ),
-                      child: ListView(
-                        controller: scrollController ?? ScrollController(),
-                        shrinkWrap: true,
-                        children: scrollableContent,
-                      ),
-                    ),
-                  ),
-                )
-              : content,
-          contentPadding: scrollableContent != null ? EdgeInsets.zero : EdgeInsets.fromLTRB(24, 20, 24, 0),
-          actions: actions,
-          actionsPadding: EdgeInsets.symmetric(horizontal: 8),
-          shape: RoundedRectangleBorder(
-            borderRadius: BorderRadius.circular(24),
-          ),
-        );
-}
-
-class DialogTitle extends StatelessWidget {
-  final String title;
-
-  const DialogTitle({@required this.title});
-
-  @override
-  Widget build(BuildContext context) {
-    return Container(
-      alignment: Alignment.center,
-      padding: const EdgeInsets.symmetric(vertical: 20),
-      decoration: BoxDecoration(
-        border: Border(
-          bottom: Divider.createBorderSide(context, width: 1),
-        ),
-      ),
-      child: Text(
-        title,
-        style: TextStyle(
-          fontWeight: FontWeight.bold,
-          fontFamily: 'Concourse Caps',
-        ),
-      ),
-    );
-  }
-}

lib/widgets/common/aves_highlight.dart

@@ -0,0 +1,101 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+import 'package:highlight/highlight.dart' show highlight, Node;
+
+// TODO TLAD use the TextSpan getter instead of this modified `HighlightView` when this is fixed: https://github.com/git-touch/highlight/issues/6
+
+/// Highlight Flutter Widget
+class AvesHighlightView extends StatelessWidget {
+  /// The original code to be highlighted
+  final String source;
+
+  /// Highlight language
+  ///
+  /// It is recommended to give it a value for performance
+  ///
+  /// [All available languages](https://github.com/pd4d10/highlight/tree/master/highlight/lib/languages)
+  final String language;
+
+  /// Highlight theme
+  ///
+  /// [All available themes](https://github.com/pd4d10/highlight/blob/master/flutter_highlight/lib/themes)
+  final Map<String, TextStyle> theme;
+
+  /// Padding
+  final EdgeInsetsGeometry padding;
+
+  /// Text styles
+  ///
+  /// Specify text styles such as font family and font size
+  final TextStyle textStyle;
+
+  AvesHighlightView(
+    String input, {
+    this.language,
+    this.theme = const {},
+    this.padding,
+    this.textStyle,
+    int tabSize = 8, // TODO: https://github.com/flutter/flutter/issues/50087
+  }) : source = input.replaceAll('\t', ' ' * tabSize);
+
+  List<TextSpan> _convert(List<Node> nodes) {
+    final spans = <TextSpan>[];
+    var currentSpans = spans;
+    final stack = <List<TextSpan>>[];
+
+    void _traverse(Node node) {
+      if (node.value != null) {
+        currentSpans.add(node.className == null ? TextSpan(text: node.value) : TextSpan(text: node.value, style: theme[node.className]));
+      } else if (node.children != null) {
+        final tmp = <TextSpan>[];
+        currentSpans.add(TextSpan(children: tmp, style: theme[node.className]));
+        stack.add(currentSpans);
+        currentSpans = tmp;
+
+        node.children.forEach((n) {
+          _traverse(n);
+          if (n == node.children.last) {
+            currentSpans = stack.isEmpty ? spans : stack.removeLast();
+          }
+        });
+      }
+    }
+
+    for (var node in nodes) {
+      _traverse(node);
+    }
+
+    return spans;
+  }
+
+  static const _rootKey = 'root';
+  static const _defaultFontColor = Color(0xff000000);
+  static const _defaultBackgroundColor = Color(0xffffffff);
+
+  // TODO: dart:io is not available at web platform currently
+  // See: https://github.com/flutter/flutter/issues/39998
+  // So we just use monospace here for now
+  static const _defaultFontFamily = 'monospace';
+
+  @override
+  Widget build(BuildContext context) {
+    var _textStyle = TextStyle(
+      fontFamily: _defaultFontFamily,
+      color: theme[_rootKey]?.color ?? _defaultFontColor,
+    );
+    if (textStyle != null) {
+      _textStyle = _textStyle.merge(textStyle);
+    }
+
+    return Container(
+      color: theme[_rootKey]?.backgroundColor ?? _defaultBackgroundColor,
+      padding: padding,
+      child: SelectableText.rich(
+        TextSpan(
+          style: _textStyle,
+          children: _convert(highlight.parse(source, language: language).nodes),
+        ),
+      ),
+    );
+  }
+}

lib/widgets/common/basic/link_chip.dart

@@ -1,4 +1,4 @@
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/material.dart';
 import 'package:url_launcher/url_launcher.dart';
 

lib/widgets/common/basic/menu_row.dart

@@ -1,4 +1,4 @@
-import 'package:aves/widgets/common/icons.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:flutter/material.dart';
 
 class MenuRow extends StatelessWidget {

lib/widgets/common/basic/reselectable_radio_list_tile.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 
 // `RadioListTile` that can trigger `onChanged` on tap when already selected, if `reselectable` is true
-class AvesRadioListTile<T> extends StatelessWidget {
+class ReselectableRadioListTile<T> extends StatelessWidget {
   final T value;
   final T groupValue;
   final ValueChanged<T> onChanged;
@@ -19,7 +19,7 @@ class AvesRadioListTile<T> extends StatelessWidget {
 
   bool get checked => value == groupValue;
 
-  const AvesRadioListTile({
+  const ReselectableRadioListTile({
     Key key,
     @required this.value,
     @required this.groupValue,

lib/widgets/common/behaviour/double_back_pop.dart

@@ -1,8 +1,8 @@
 import 'dart:async';
 
 import 'package:aves/model/settings/settings.dart';
-import 'package:aves/utils/durations.dart';
-import 'package:aves/widgets/common/action_delegates/feedback.dart';
+import 'package:aves/theme/durations.dart';
+import 'package:aves/widgets/common/action_mixins/feedback.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:overlay_support/overlay_support.dart';

lib/widgets/common/behaviour/routes.dart

@@ -1,5 +1,9 @@
 import 'package:flutter/material.dart';
 
+extension ExtraContext on BuildContext {
+  String get currentRouteName => ModalRoute.of(this)?.settings?.name;
+}
+
 class DirectMaterialPageRoute<T> extends PageRouteBuilder<T> {
   DirectMaterialPageRoute({
     RouteSettings settings,

lib/widgets/common/fx/sweeper.dart

@@ -1,6 +1,6 @@
 import 'dart:math';
 
-import 'package:aves/utils/durations.dart';
+import 'package:aves/theme/durations.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/scheduler.dart';
 

lib/widgets/common/identity/aves_expansion_tile.dart

@@ -1,14 +1,16 @@
-import 'package:aves/widgets/common/highlight_title.dart';
+import 'package:aves/widgets/common/identity/highlight_title.dart';
 import 'package:expansion_tile_card/expansion_tile_card.dart';
 import 'package:flutter/material.dart';
 
 class AvesExpansionTile extends StatelessWidget {
   final String title;
+  final Color color;
   final List<Widget> children;
   final ValueNotifier<String> expandedNotifier;
 
   const AvesExpansionTile({
     @required this.title,
+    this.color,
     this.expandedNotifier,
     @required this.children,
   });
@@ -27,6 +29,7 @@ class AvesExpansionTile extends StatelessWidget {
         expandedNotifier: expandedNotifier,
         title: HighlightTitle(
           title,
+          color: color,
           fontSize: 18,
           enabled: enabled,
         ),

lib/widgets/common/identity/aves_filter_chip.dart

@@ -1,6 +1,6 @@
 import 'package:aves/model/filters/filters.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/utils/constants.dart';
-import 'package:aves/widgets/common/icons.dart';
 import 'package:flutter/material.dart';
 
 typedef FilterCallback = void Function(CollectionFilter filter);
@@ -14,29 +14,33 @@ class AvesFilterChip extends StatefulWidget {
   final bool showGenericIcon;
   final Widget background;
   final Widget details;
+  final double padding;
   final HeroType heroType;
   final FilterCallback onTap;
   final OffsetFilterCallback onLongPress;
+  final BorderRadius borderRadius;
 
-  static final BorderRadius borderRadius = BorderRadius.circular(32);
+  static const double defaultRadius = 32;
   static const double outlineWidth = 2;
   static const double minChipHeight = kMinInteractiveDimension;
   static const double minChipWidth = 80;
   static const double maxChipWidth = 160;
   static const double iconSize = 20;
-  static const double padding = 6;
 
   const AvesFilterChip({
     Key key,
-    this.filter,
+    @required this.filter,
     this.removable = false,
     this.showGenericIcon = true,
     this.background,
     this.details,
+    this.borderRadius = const BorderRadius.all(Radius.circular(defaultRadius)),
+    this.padding = 6.0,
     this.heroType = HeroType.onTap,
-    @required this.onTap,
+    this.onTap,
     this.onLongPress,
-  }) : super(key: key);
+  })  : assert(filter != null),
+        super(key: key);
 
   @override
   _AvesFilterChipState createState() => _AvesFilterChipState();
@@ -50,6 +54,10 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
 
   CollectionFilter get filter => widget.filter;
 
+  BorderRadius get borderRadius => widget.borderRadius;
+
+  double get padding => widget.padding;
+
   @override
   void initState() {
     super.initState();
@@ -79,9 +87,11 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
 
   @override
   Widget build(BuildContext context) {
+    const iconSize = AvesFilterChip.iconSize;
+
     final hasBackground = widget.background != null;
-    final leading = filter.iconBuilder(context, AvesFilterChip.iconSize, showGenericIcon: widget.showGenericIcon, embossed: hasBackground);
-    final trailing = widget.removable ? Icon(AIcons.clear, size: AvesFilterChip.iconSize) : null;
+    final leading = filter.iconBuilder(context, iconSize, showGenericIcon: widget.showGenericIcon, embossed: hasBackground);
+    final trailing = widget.removable ? Icon(AIcons.clear, size: iconSize) : null;
 
     Widget content = Row(
       mainAxisSize: hasBackground ? MainAxisSize.max : MainAxisSize.min,
@@ -89,7 +99,7 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
       children: [
         if (leading != null) ...[
           leading,
-          SizedBox(width: AvesFilterChip.padding),
+          SizedBox(width: padding),
         ],
         Flexible(
           child: Text(
@@ -100,7 +110,7 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
           ),
         ),
         if (trailing != null) ...[
-          SizedBox(width: AvesFilterChip.padding),
+          SizedBox(width: padding),
           trailing,
         ],
       ],
@@ -117,7 +127,7 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
     }
 
     content = Padding(
-      padding: EdgeInsets.symmetric(horizontal: AvesFilterChip.padding * 2, vertical: 2),
+      padding: EdgeInsets.symmetric(horizontal: padding * 2, vertical: 2),
       child: content,
     );
 
@@ -135,8 +145,6 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
       );
     }
 
-    final borderRadius = AvesFilterChip.borderRadius;
-
     Widget chip = Container(
       constraints: BoxConstraints(
         minWidth: AvesFilterChip.minChipWidth,

lib/widgets/common/identity/aves_icons.dart

@@ -1,77 +1,12 @@
 import 'dart:ui';
 
+import 'package:aves/image_providers/app_icon_image_provider.dart';
 import 'package:aves/model/image_entry.dart';
+import 'package:aves/theme/icons.dart';
 import 'package:aves/utils/android_file_utils.dart';
 import 'package:aves/utils/constants.dart';
-import 'package:aves/widgets/common/image_providers/app_icon_image_provider.dart';
 import 'package:decorated_icon/decorated_icon.dart';
 import 'package:flutter/material.dart';
-import 'package:material_design_icons_flutter/material_design_icons_flutter.dart';
-
-class AIcons {
-  static const IconData allCollection = Icons.collections_outlined;
-  static const IconData image = Icons.photo_outlined;
-  static const IconData video = Icons.movie_outlined;
-  static const IconData audio = Icons.audiotrack_outlined;
-  static const IconData vector = Icons.code_outlined;
-
-  static const IconData android = Icons.android;
-  static const IconData checked = Icons.done_outlined;
-  static const IconData date = Icons.calendar_today_outlined;
-  static const IconData disc = Icons.fiber_manual_record;
-  static const IconData error = Icons.error_outline;
-  static const IconData location = Icons.place_outlined;
-  static const IconData locationOff = Icons.location_off_outlined;
-  static const IconData raw = Icons.camera_outlined;
-  static const IconData shooting = Icons.camera_outlined;
-  static const IconData removableStorage = Icons.sd_storage_outlined;
-  static const IconData settings = Icons.settings_outlined;
-  static const IconData text = Icons.format_quote_outlined;
-  static const IconData tag = Icons.local_offer_outlined;
-  static const IconData tagOff = MdiIcons.tagOffOutline;
-
-  // actions
-  static const IconData addShortcut = Icons.add_to_home_screen_outlined;
-  static const IconData clear = Icons.clear_outlined;
-  static const IconData collapse = Icons.expand_less_outlined;
-  static const IconData createAlbum = Icons.add_circle_outline;
-  static const IconData debug = Icons.whatshot_outlined;
-  static const IconData delete = Icons.delete_outlined;
-  static const IconData expand = Icons.expand_more_outlined;
-  static const IconData flip = Icons.flip_outlined;
-  static const IconData favourite = Icons.favorite_border;
-  static const IconData favouriteActive = Icons.favorite;
-  static const IconData goUp = Icons.arrow_upward_outlined;
-  static const IconData group = Icons.group_work_outlined;
-  static const IconData info = Icons.info_outlined;
-  static const IconData layers = Icons.layers_outlined;
-  static const IconData openInNew = Icons.open_in_new_outlined;
-  static const IconData pin = Icons.push_pin_outlined;
-  static const IconData print = Icons.print_outlined;
-  static const IconData refresh = Icons.refresh_outlined;
-  static const IconData rename = Icons.title_outlined;
-  static const IconData rotateLeft = Icons.rotate_left_outlined;
-  static const IconData rotateRight = Icons.rotate_right_outlined;
-  static const IconData search = Icons.search_outlined;
-  static const IconData select = Icons.select_all_outlined;
-  static const IconData share = Icons.share_outlined;
-  static const IconData sort = Icons.sort_outlined;
-  static const IconData stats = Icons.pie_chart_outlined;
-  static const IconData zoomIn = Icons.add_outlined;
-  static const IconData zoomOut = Icons.remove_outlined;
-
-  // albums
-  static const IconData album = Icons.photo_album_outlined;
-  static const IconData cameraAlbum = Icons.photo_camera_outlined;
-  static const IconData downloadAlbum = Icons.file_download;
-  static const IconData screenshotAlbum = Icons.smartphone_outlined;
-
-  // thumbnail overlay
-  static const IconData animated = Icons.slideshow;
-  static const IconData play = Icons.play_circle_outline;
-  static const IconData selected = Icons.check_circle_outline;
-  static const IconData unselected = Icons.radio_button_unchecked;
-}
 
 class VideoIcon extends StatelessWidget {
   final ImageEntry entry;

lib/widgets/common/identity/highlight_title.dart

@@ -4,11 +4,13 @@ import 'package:flutter/material.dart';
 
 class HighlightTitle extends StatelessWidget {
   final String name;
+  final Color color;
   final double fontSize;
   final bool enabled;
 
   const HighlightTitle(
     this.name, {
+    this.color,
     this.fontSize = 20,
     this.enabled = true,
   }) : assert(name != null);
@@ -21,7 +23,7 @@ class HighlightTitle extends StatelessWidget {
       alignment: AlignmentDirectional.centerStart,
       child: Container(
         decoration: HighlightDecoration(
-          color: enabled ? stringToColor(name) : disabledColor,
+          color: enabled ? color ?? stringToColor(name) : disabledColor,
         ),
         margin: EdgeInsets.symmetric(vertical: 4.0),
         child: Text(

lib/widgets/common/providers/highlight_info_provider.dart

@@ -0,0 +1,17 @@
+import 'package:aves/model/highlight.dart';
+import 'package:flutter/widgets.dart';
+import 'package:provider/provider.dart';
+
+class HighlightInfoProvider extends StatelessWidget {
+  final Widget child;
+
+  const HighlightInfoProvider({@required this.child});
+
+  @override
+  Widget build(BuildContext context) {
+    return ChangeNotifierProvider<HighlightInfo>(
+      create: (context) => HighlightInfo(),
+      child: child,
+    );
+  }
+}

lib/widgets/common/scaling.dart

@@ -1,48 +1,57 @@
 import 'dart:math';
 import 'dart:ui' as ui;
 
-import 'package:aves/model/image_entry.dart';
-import 'package:aves/utils/durations.dart';
-import 'package:aves/widgets/collection/grid/list_section_layout.dart';
-import 'package:aves/widgets/collection/grid/list_sliver.dart';
-import 'package:aves/widgets/collection/grid/tile_extent_manager.dart';
+import 'package:aves/theme/durations.dart';
 import 'package:aves/widgets/collection/thumbnail/decorated.dart';
-import 'package:aves/widgets/common/data_providers/media_query_data_provider.dart';
+import 'package:aves/widgets/common/providers/media_query_data_provider.dart';
+import 'package:aves/widgets/common/tile_extent_manager.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
-import 'package:provider/provider.dart';
 
-class GridScaleGestureDetector extends StatefulWidget {
+// metadata to identify entry from RenderObject hit test during collection scaling
+class ScalerMetadata<T> {
+  final T item;
+
+  const ScalerMetadata(this.item);
+}
+
+class GridScaleGestureDetector<T> extends StatefulWidget {
+  final TileExtentManager tileExtentManager;
   final GlobalKey scrollableKey;
   final ValueNotifier<double> appBarHeightNotifier;
-  final ValueNotifier<double> extentNotifier;
-  final Size mqSize;
-  final double mqHorizontalPadding;
-  final void Function(ImageEntry entry) onScaled;
+  final Size viewportSize;
+  final bool showScaledGrid;
+  final Widget Function(T item, double extent) scaledBuilder;
+  final Rect Function(BuildContext context, T item) getScaledItemTileRect;
+  final void Function(T item) onScaled;
   final Widget child;
 
   const GridScaleGestureDetector({
-    this.scrollableKey,
+    @required this.tileExtentManager,
+    @required this.scrollableKey,
     @required this.appBarHeightNotifier,
-    @required this.extentNotifier,
-    @required this.mqSize,
-    @required this.mqHorizontalPadding,
-    this.onScaled,
+    @required this.viewportSize,
+    @required this.showScaledGrid,
+    @required this.scaledBuilder,
+    @required this.getScaledItemTileRect,
+    @required this.onScaled,
     @required this.child,
   });
 
   @override
-  _GridScaleGestureDetectorState createState() => _GridScaleGestureDetectorState();
+  _GridScaleGestureDetectorState createState() => _GridScaleGestureDetectorState<T>();
 }
 
-class _GridScaleGestureDetectorState extends State<GridScaleGestureDetector> {
+class _GridScaleGestureDetectorState<T> extends State<GridScaleGestureDetector<T>> {
   double _startExtent, _extentMin, _extentMax;
   bool _applyingScale = false;
   ValueNotifier<double> _scaledExtentNotifier;
   OverlayEntry _overlayEntry;
-  ThumbnailMetadata _metadata;
+  ScalerMetadata<T> _metadata;
 
-  ValueNotifier<double> get tileExtentNotifier => widget.extentNotifier;
+  TileExtentManager get tileExtentManager => widget.tileExtentManager;
+
+  Size get viewportSize => widget.viewportSize;
 
   @override
   Widget build(BuildContext context) {
@@ -62,29 +71,31 @@ class _GridScaleGestureDetectorState extends State<GridScaleGestureDetector> {
         scrollableBox.hitTest(result, position: details.localFocalPoint);
 
         // find `RenderObject`s at the gesture focal point
-        T firstOf<T>(BoxHitTestResult result) => result.path.firstWhere((el) => el.target is T, orElse: () => null)?.target as T;
+        U firstOf<U>(BoxHitTestResult result) => result.path.firstWhere((el) => el.target is U, orElse: () => null)?.target as U;
         final renderMetaData = firstOf<RenderMetaData>(result);
         // abort if we cannot find an image to show on overlay
         if (renderMetaData == null) return;
         _metadata = renderMetaData.metaData;
-        _startExtent = tileExtentNotifier.value;
+        _startExtent = renderMetaData.size.width;
         _scaledExtentNotifier = ValueNotifier(_startExtent);
 
         // not the same as `MediaQuery.size.width`, because of screen insets/padding
         final gridWidth = scrollableBox.size.width;
-        _extentMin = gridWidth / (gridWidth / TileExtentManager.tileExtentMin).round();
-        _extentMax = gridWidth / (gridWidth / TileExtentManager.extentMaxForSize(widget.mqSize)).round();
+
+        _extentMin = tileExtentManager.getEffectiveExtentMin(viewportSize);
+        _extentMax = tileExtentManager.getEffectiveExtentMax(viewportSize);
+
         final halfExtent = _startExtent / 2;
         final thumbnailCenter = renderMetaData.localToGlobal(Offset(halfExtent, halfExtent));
         _overlayEntry = OverlayEntry(
-          builder: (context) {
-            return ScaleOverlay(
-              imageEntry: _metadata.entry,
-              center: thumbnailCenter,
-              gridWidth: gridWidth,
-              scaledExtentNotifier: _scaledExtentNotifier,
-            );
-          },
+          builder: (context) => ScaleOverlay(
+            builder: (extent) => widget.scaledBuilder(_metadata.item, extent),
+            center: thumbnailCenter,
+            gridWidth: gridWidth,
+            spacing: tileExtentManager.spacing,
+            scaledExtentNotifier: _scaledExtentNotifier,
+            showScaledGrid: widget.showScaledGrid,
+          ),
         );
         Overlay.of(scrollableContext).insert(_overlayEntry);
       },
@@ -101,13 +112,11 @@ class _GridScaleGestureDetectorState extends State<GridScaleGestureDetector> {
         }
 
         _applyingScale = true;
-        final oldExtent = tileExtentNotifier.value;
+        final oldExtent = tileExtentManager.extentNotifier.value;
         // sanitize and update grid layout if necessary
-        final newExtent = TileExtentManager.applyTileExtent(
-          widget.mqSize,
-          widget.mqHorizontalPadding,
-          tileExtentNotifier,
-          newExtent: _scaledExtentNotifier.value,
+        final newExtent = tileExtentManager.applyTileExtent(
+          viewportSize: widget.viewportSize,
+          userPreferredExtent: _scaledExtentNotifier.value,
         );
         _scaledExtentNotifier = null;
         if (newExtent == oldExtent) {
@@ -115,8 +124,8 @@ class _GridScaleGestureDetectorState extends State<GridScaleGestureDetector> {
         } else {
           // scroll to show the focal point thumbnail at its new position
           WidgetsBinding.instance.addPostFrameCallback((_) {
-            final entry = _metadata.entry;
-            _scrollToEntry(entry);
+            final entry = _metadata.item;
+            _scrollToItem(entry);
             // warning: posting `onScaled` in the next frame with `addPostFrameCallback`
             // would trigger only when the scrollable offset actually changes
             Future.delayed(Durations.collectionScalingCompleteNotificationDelay).then((_) => widget.onScaled?.call(entry));
@@ -132,11 +141,10 @@ class _GridScaleGestureDetectorState extends State<GridScaleGestureDetector> {
   // `Scrollable.ensureVisible` only works on already rendered objects
   // `RenderViewport.showOnScreen` can find any `RenderSliver`, but not always a `RenderMetadata`
   // `RenderViewport.scrollOffsetOf` is a good alternative
-  void _scrollToEntry(ImageEntry entry) {
+  void _scrollToItem(T item) {
     final scrollableContext = widget.scrollableKey.currentContext;
     final scrollableHeight = (scrollableContext.findRenderObject() as RenderBox).size.height;
-    final sectionedListLayout = Provider.of<SectionedListLayout>(context, listen: false);
-    final tileRect = sectionedListLayout.getTileRect(entry) ?? Rect.zero;
+    final tileRect = widget.getScaledItemTileRect(context, item);
     // most of the time the app bar will be scrolled away after scaling,
     // so we compensate for it to center the focal point thumbnail
     final appBarHeight = widget.appBarHeightNotifier.value;
@@ -147,16 +155,20 @@ class _GridScaleGestureDetectorState extends State<GridScaleGestureDetector> {
 }
 
 class ScaleOverlay extends StatefulWidget {
-  final ImageEntry imageEntry;
+  final Widget Function(double extent) builder;
   final Offset center;
   final double gridWidth;
+  final double spacing;
   final ValueNotifier<double> scaledExtentNotifier;
+  final bool showScaledGrid;
 
   const ScaleOverlay({
-    @required this.imageEntry,
+    @required this.builder,
     @required this.center,
     @required this.gridWidth,
+    @required this.spacing,
     @required this.scaledExtentNotifier,
+    @required this.showScaledGrid,
   });
 
   @override
@@ -216,28 +228,30 @@ class _ScaleOverlayState extends State<ScaleOverlay> {
               }
               final clampedCenter = center.translate(dx, 0);
 
-              return CustomPaint(
-                painter: GridPainter(
-                  center: clampedCenter,
-                  extent: extent,
-                ),
-                child: Stack(
-                  children: [
-                    Positioned(
-                      left: clampedCenter.dx - extent / 2,
-                      top: clampedCenter.dy - extent / 2,
-                      child: DefaultTextStyle(
-                        style: TextStyle(),
-                        child: DecoratedThumbnail(
-                          entry: widget.imageEntry,
-                          extent: extent,
-                          showOverlay: false,
-                        ),
-                      ),
+              var child = widget.builder(extent);
+              child = Stack(
+                children: [
+                  Positioned(
+                    left: clampedCenter.dx - extent / 2,
+                    top: clampedCenter.dy - extent / 2,
+                    child: DefaultTextStyle(
+                      style: TextStyle(),
+                      child: child,
                     ),
-                  ],
-                ),
+                  ),
+                ],
               );
+              if (widget.showScaledGrid) {
+                child = CustomPaint(
+                  painter: GridPainter(
+                    center: clampedCenter,
+                    extent: extent,
+                    spacing: widget.spacing,
+                  ),
+                  child: child,
+                );
+              }
+              return child;
             },
           ),
         ),
@@ -248,11 +262,12 @@ class _ScaleOverlayState extends State<ScaleOverlay> {
 
 class GridPainter extends CustomPainter {
   final Offset center;
-  final double extent;
+  final double extent, spacing;
 
   const GridPainter({
     @required this.center,
     @required this.extent,
+    @required this.spacing,
   });
 
   @override
@@ -261,7 +276,7 @@ class GridPainter extends CustomPainter {
       ..strokeWidth = DecoratedThumbnail.borderWidth
       ..shader = ui.Gradient.radial(
         center,
-        size.width / 2,
+        size.width * .7,
         [
           DecoratedThumbnail.borderColor,
           Colors.transparent,
@@ -271,10 +286,18 @@ class GridPainter extends CustomPainter {
           1,
         ],
       );
+    void draw(Offset topLeft) {
+      for (var i = -2; i <= 3; i++) {
+        final ref = (extent + spacing) * i;
+        canvas.drawLine(Offset(0, topLeft.dy + ref), Offset(size.width, topLeft.dy + ref), paint);
+        canvas.drawLine(Offset(topLeft.dx + ref, 0), Offset(topLeft.dx + ref, size.height), paint);
+      }
+    }
+
     final topLeft = center.translate(-extent / 2, -extent / 2);
-    for (var i = -1; i <= 2; i++) {
-      canvas.drawLine(Offset(0, topLeft.dy + extent * i), Offset(size.width, topLeft.dy + extent * i), paint);
-      canvas.drawLine(Offset(topLeft.dx + extent * i, 0), Offset(topLeft.dx + extent * i, size.height), paint);
+    draw(topLeft);
+    if (spacing > 0) {
+      draw(topLeft.translate(-spacing, -spacing));
     }
   }
 

lib/widgets/common/tile_extent_manager.dart

@@ -0,0 +1,70 @@
+import 'dart:math';
+
+import 'package:aves/model/settings/settings.dart';
+import 'package:flutter/widgets.dart';
+
+class TileExtentManager {
+  final String settingsRouteKey;
+  final int columnCountMin, columnCountDefault;
+  final double spacing, extentMin;
+  final ValueNotifier<double> extentNotifier;
+
+  const TileExtentManager({
+    @required this.settingsRouteKey,
+    @required this.columnCountMin,
+    @required this.columnCountDefault,
+    @required this.extentMin,
+    @required this.extentNotifier,
+    @required this.spacing,
+  });
+
+  double applyTileExtent({
+    @required Size viewportSize,
+    double userPreferredExtent = 0,
+  }) {
+    // sanitize screen size (useful when reloading while screen is off, reporting a 0,0 size)
+    final viewportSizeMin = Size.square(extentMin * columnCountMin);
+    viewportSize = Size(max(viewportSize.width, viewportSizeMin.width), max(viewportSize.height, viewportSizeMin.height));
+
+    final oldUserPreferredExtent = settings.getTileExtent(settingsRouteKey);
+    final currentExtent = extentNotifier.value;
+    final targetExtent = userPreferredExtent > 0
+        ? userPreferredExtent
+        : oldUserPreferredExtent > 0
+            ? oldUserPreferredExtent
+            : currentExtent;
+
+    final columnCount = getEffectiveColumnCountForExtent(viewportSize, targetExtent);
+    final newExtent = _extentForColumnCount(viewportSize, columnCount);
+
+    if (userPreferredExtent > 0 || oldUserPreferredExtent == 0) {
+      settings.setTileExtent(settingsRouteKey, newExtent);
+    }
+    if (extentNotifier.value != newExtent) {
+      extentNotifier.value = newExtent;
+    }
+    return newExtent;
+  }
+
+  double _extentMax(Size viewportSize) => (viewportSize.shortestSide - spacing * (columnCountMin - 1)) / columnCountMin;
+
+  double _columnCountForExtent(Size viewportSize, double extent) => (viewportSize.width + spacing) / (extent + spacing);
+
+  double _extentForColumnCount(Size viewportSize, int columnCount) => (viewportSize.width - spacing * (columnCount - 1)) / columnCount;
+
+  int _effectiveColumnCountMin(Size viewportSize) => _columnCountForExtent(viewportSize, _extentMax(viewportSize)).ceil();
+
+  int _effectiveColumnCountMax(Size viewportSize) => _columnCountForExtent(viewportSize, extentMin).floor();
+
+  double getEffectiveExtentMin(Size viewportSize) => _extentForColumnCount(viewportSize, _effectiveColumnCountMax(viewportSize));
+
+  double getEffectiveExtentMax(Size viewportSize) => _extentForColumnCount(viewportSize, _effectiveColumnCountMin(viewportSize));
+
+  int getEffectiveColumnCountForExtent(Size viewportSize, double extent) {
+    if (extent > 0) {
+      final columnCount = _columnCountForExtent(viewportSize, extent);
+      return columnCount.clamp(_effectiveColumnCountMin(viewportSize), _effectiveColumnCountMax(viewportSize)).round();
+    }
+    return columnCountDefault;
+  }
+}

lib/widgets/debug/android_env.dart

@@ -1,7 +1,7 @@
 import 'dart:collection';
 
 import 'package:aves/services/android_app_service.dart';
-import 'package:aves/widgets/common/aves_expansion_tile.dart';
+import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
 import 'package:aves/widgets/fullscreen/info/common.dart';
 import 'package:flutter/material.dart';
 

lib/widgets/debug/app_debug_page.dart

@@ -1,7 +1,7 @@
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/source/collection_source.dart';
-import 'package:aves/widgets/common/aves_expansion_tile.dart';
-import 'package:aves/widgets/common/data_providers/media_query_data_provider.dart';
+import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
+import 'package:aves/widgets/common/providers/media_query_data_provider.dart';
 import 'package:aves/widgets/debug/android_env.dart';
 import 'package:aves/widgets/debug/cache.dart';
 import 'package:aves/widgets/debug/database.dart';

lib/widgets/debug/cache.dart

@@ -1,6 +1,6 @@
 import 'package:aves/services/image_file_service.dart';
 import 'package:aves/utils/file_utils.dart';
-import 'package:aves/widgets/common/aves_expansion_tile.dart';
+import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_svg/flutter_svg.dart';