feat(album): batch download selected tracks

lib/widgets/track_detail_actions.dart

@@ -118,6 +118,12 @@ void showQueuedSnackbar(BuildContext context, int added, int skipped) {
   ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(message)));
 }
 
+bool shouldShowBatchDownloadPicker({
+  required bool forceQualityPicker,
+  required bool askQualityBeforeDownload,
+  required bool allowQualityVariants,
+}) => forceQualityPicker || askQualityBeforeDownload || allowQualityVariants;
+
 /// Shared batch "add to queue" flow for detail screens: skips tracks already
 /// present in download history or the local library, then either shows the
 /// quality/service picker or resolves a default service, before enqueueing
@@ -126,6 +132,9 @@ void showQueuedSnackbar(BuildContext context, int added, int skipped) {
 /// Set [resolveDefaultService] to false to match screens that pass
 /// `settings.defaultService` straight through without resolving it against
 /// enabled extensions (playlist / library-folder screens do this today).
+/// [forceQualityPicker] lets an explicit multi-select action choose one
+/// provider and quality for the complete batch. [onQueued] runs only after
+/// tracks are actually added, not when the picker is merely opened.
 Future<void> queueTracksSkippingDownloaded(
   BuildContext context,
   WidgetRef ref,
@@ -134,6 +143,8 @@ Future<void> queueTracksSkippingDownloaded(
   String? recommendedService,
   String? playlistName,
   bool resolveDefaultService = true,
+  bool forceQualityPicker = false,
+  VoidCallback? onQueued,
 }) async {
   if (tracks.isEmpty) return;
 
@@ -198,7 +209,11 @@ Future<void> queueTracksSkippingDownloaded(
     return;
   }
 
-  if (settings.askQualityBeforeDownload || settings.allowQualityVariants) {
+  if (shouldShowBatchDownloadPicker(
+    forceQualityPicker: forceQualityPicker,
+    askQualityBeforeDownload: settings.askQualityBeforeDownload,
+    allowQualityVariants: settings.allowQualityVariants,
+  )) {
     DownloadServicePicker.show(
       context,
       trackName: '${tracksToQueue.length} tracks',
@@ -213,6 +228,7 @@ Future<void> queueTracksSkippingDownloaded(
               qualityOverride: quality,
               playlistName: playlistName,
             );
+        onQueued?.call();
         showQueuedSnackbar(context, tracksToQueue.length, skippedCount);
       },
     );
@@ -238,6 +254,7 @@ Future<void> queueTracksSkippingDownloaded(
   ref
       .read(downloadQueueProvider.notifier)
       .addMultipleToQueue(tracksToQueue, service, playlistName: playlistName);
+  onQueued?.call();
   showQueuedSnackbar(context, tracksToQueue.length, skippedCount);
 }
 

lib/widgets/track_list_tile.dart

@@ -7,6 +7,7 @@ import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/utils/clickable_metadata.dart';
 import 'package:spotiflac_android/utils/local_playback.dart';
 import 'package:spotiflac_android/widgets/audio_quality_badges.dart';
+import 'package:spotiflac_android/widgets/animation_utils.dart';
 import 'package:spotiflac_android/widgets/in_library_badge.dart';
 import 'package:spotiflac_android/widgets/preview_button.dart';
 import 'package:spotiflac_android/widgets/track_collection_quick_actions.dart';
@@ -22,6 +23,10 @@ class TrackListTile extends ConsumerWidget {
   final void Function({bool forceQualityPicker}) onDownload;
   final Widget leading;
   final bool clickableArtist;
+  final bool isSelectionMode;
+  final bool isSelected;
+  final VoidCallback? onToggleSelection;
+  final VoidCallback? onEnterSelectionMode;
 
   const TrackListTile({
     super.key,
@@ -30,7 +35,11 @@ class TrackListTile extends ConsumerWidget {
     required this.onDownload,
     required this.leading,
     this.clickableArtist = false,
-  });
+    this.isSelectionMode = false,
+    this.isSelected = false,
+    this.onToggleSelection,
+    this.onEnterSelectionMode,
+  }) : assert(!isSelectionMode || onToggleSelection != null);
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
@@ -65,13 +74,29 @@ class TrackListTile extends ConsumerWidget {
       padding: const EdgeInsets.symmetric(horizontal: 8),
       child: Card(
         elevation: 0,
-        color: Colors.transparent,
+        color: isSelected
+            ? colorScheme.primaryContainer.withValues(alpha: 0.3)
+            : Colors.transparent,
         margin: const EdgeInsets.symmetric(vertical: 2),
         child: ListTile(
           shape: RoundedRectangleBorder(
             borderRadius: BorderRadius.circular(12),
           ),
-          leading: leading,
+          leading: Row(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              if (isSelectionMode) ...[
+                AnimatedSelectionCheckbox(
+                  visible: true,
+                  selected: isSelected,
+                  colorScheme: colorScheme,
+                  size: 24,
+                ),
+                const SizedBox(width: 12),
+              ],
+              leading,
+            ],
+          ),
           title: Text(
             track.name,
             maxLines: 1,
@@ -83,7 +108,7 @@ class TrackListTile extends ConsumerWidget {
           subtitle: Row(
             children: [
               Flexible(
-                child: clickableArtist
+                child: clickableArtist && !isSelectionMode
                     ? ClickableArtistName(
                         artistName: track.artistName,
                         artistId: track.artistId,
@@ -112,28 +137,37 @@ class TrackListTile extends ConsumerWidget {
               ],
             ],
           ),
-          trailing: Row(
-            mainAxisSize: MainAxisSize.min,
-            children: [
-              PreviewButton(track: track),
-              TrackCollectionQuickActions(
-                track: track,
-                hasLocalPlaybackCandidate: isInHistory || isInLocalLibrary,
-              ),
-            ],
-          ),
-          onTap: () => _handleTap(
-            context,
-            ref,
-            isQueued: isQueued,
-            isInLocalLibrary: isInLocalLibrary,
-          ),
-          onLongPress: () => TrackCollectionQuickActions.showTrackOptionsSheet(
-            context,
-            ref,
-            track,
-            hasLocalPlaybackCandidate: isInHistory || isInLocalLibrary,
-          ),
+          trailing: isSelectionMode
+              ? null
+              : Row(
+                  mainAxisSize: MainAxisSize.min,
+                  children: [
+                    PreviewButton(track: track),
+                    TrackCollectionQuickActions(
+                      track: track,
+                      hasLocalPlaybackCandidate:
+                          isInHistory || isInLocalLibrary,
+                    ),
+                  ],
+                ),
+          onTap: isSelectionMode
+              ? onToggleSelection
+              : () => _handleTap(
+                  context,
+                  ref,
+                  isQueued: isQueued,
+                  isInLocalLibrary: isInLocalLibrary,
+                ),
+          onLongPress: isSelectionMode
+              ? null
+              : onEnterSelectionMode ??
+                    () => TrackCollectionQuickActions.showTrackOptionsSheet(
+                      context,
+                      ref,
+                      track,
+                      hasLocalPlaybackCandidate:
+                          isInHistory || isInLocalLibrary,
+                    ),
         ),
       ),
     );