Delete audio (#229)

* Refactor timeline painter

* Remove id from sliver

* Selectable sound clip

* Sound sliver menu

* Prevent file rewrite on duplicate

* Delete sound clips

* Stop playing deleted clip

* Bump version

* Update release notes

* Extract makeFreeDuplicatePath

* Final

* Unused argument

* Missing return

lib/common/data/io/disk_image.dart

@@ -33,7 +33,7 @@ class DiskImage with EquatableMixin {
   }
 
   Future<DiskImage> duplicate() async {
-    final duplicatePath = makeDuplicatePath(file.path);
+    final duplicatePath = makeFreeDuplicatePath(file.path);
     final duplicateFile = await file.copy(duplicatePath);
 
     return DiskImage(

lib/common/data/io/make_duplicate_path.dart

@@ -1,8 +1,23 @@
+import 'dart:io';
+
+import 'package:flutter/material.dart';
 import 'package:path/path.dart' as p;
 
+/// Returns an unoccupied duplicate path.
+String makeFreeDuplicatePath(String originalPath) {
+  var duplicatePath = makeDuplicatePath(originalPath);
+
+  while (File(duplicatePath).existsSync()) {
+    duplicatePath = makeDuplicatePath(duplicatePath);
+  }
+
+  return duplicatePath;
+}
+
 /// Returns a new path for a duplicate file.
 /// `example/path/image.png` -> `example/path/image_1.png`
 /// `example/path/image_1.png` -> `example/path/image_2.png`
+@visibleForTesting
 String makeDuplicatePath(String path) {
   final dir = p.dirname(path);
   final name = p.basenameWithoutExtension(path);

lib/common/data/project/sound_clip.dart

@@ -1,26 +1,24 @@
 import 'dart:io';
 
 import 'package:mooltik/common/data/extensions/duration_methods.dart';
+import 'package:mooltik/common/data/sequence/time_span.dart';
 import 'package:path/path.dart' as p;
 
-class SoundClip {
+class SoundClip extends TimeSpan {
   SoundClip({
     required this.file,
     required Duration startTime,
     required Duration duration,
   })  : _startTime = startTime,
-        _duration = duration;
+        super(duration);
 
   String get path => file.path;
   final File file;
 
   Duration get startTime => _startTime;
   Duration _startTime;
 
-  Duration get endTime => _startTime + _duration;
-
-  Duration get duration => _duration;
-  Duration _duration;
+  Duration get endTime => _startTime + duration;
 
   factory SoundClip.fromJson(Map<String, dynamic> json, String soundDirPath) =>
       SoundClip(
@@ -32,8 +30,18 @@ class SoundClip {
   Map<String, dynamic> toJson() => {
         _fileNameKey: p.basename(file.path),
         _startTimeKey: _startTime.toString(),
-        _durationKey: _duration.toString(),
+        _durationKey: duration.toString(),
       };
+
+  @override
+  SoundClip copyWith({Duration? duration}) => SoundClip(
+        file: file,
+        startTime: startTime,
+        duration: duration ?? this.duration,
+      );
+
+  @override
+  void dispose() {}
 }
 
 const String _fileNameKey = 'file_name';

lib/common/ui/popup_entry.dart

@@ -3,7 +3,7 @@ import 'package:flutter_portal/flutter_portal.dart';
 
 const _popupAnimationDuration = Duration(milliseconds: 150);
 
-class PopupEntry extends StatelessWidget {
+class PopupEntry extends StatefulWidget {
   const PopupEntry({
     Key? key,
     required this.visible,
@@ -23,37 +23,54 @@ class PopupEntry extends StatelessWidget {
   final VoidCallback? onTapOutside;
   final VoidCallback? onDragOutside;
 
+  @override
+  _PopupEntryState createState() => _PopupEntryState();
+}
+
+class _PopupEntryState extends State<PopupEntry> {
+  Widget? _popup;
+
+  @override
+  void didUpdateWidget(covariant PopupEntry oldWidget) {
+    super.didUpdateWidget(oldWidget);
+
+    // Don't update popup configuration when popup is fading out.
+    if (widget.visible) {
+      _popup = widget.popup;
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return PortalEntry(
-      visible: visible,
+      visible: widget.visible,
       portal: Listener(
         behavior: HitTestBehavior.translucent,
         onPointerUp: (_) {
-          onTapOutside?.call();
+          widget.onTapOutside?.call();
         },
         onPointerMove: (_) {
-          onDragOutside?.call();
+          widget.onDragOutside?.call();
         },
       ),
       child: PortalEntry(
-        visible: visible,
+        visible: widget.visible,
         closeDuration: _popupAnimationDuration,
         portal: TweenAnimationBuilder<double>(
           duration: _popupAnimationDuration,
-          tween: Tween(begin: 0, end: visible ? 1 : 0),
+          tween: Tween(begin: 0, end: widget.visible ? 1 : 0),
           builder: (context, progress, child) => Opacity(
             opacity: progress,
             child: child,
           ),
-          child: popup,
+          child: _popup,
         ),
-        portalAnchor: popupAnchor,
+        portalAnchor: widget.popupAnchor,
         child: IgnorePointer(
-          ignoring: visible,
-          child: child,
+          ignoring: widget.visible,
+          child: widget.child,
         ),
-        childAnchor: childAnchor,
+        childAnchor: widget.childAnchor,
       ),
     );
   }

lib/editing/data/player_model.dart

@@ -38,7 +38,7 @@ class PlayerModel extends ChangeNotifier {
     super.dispose();
   }
 
-  final AudioPlayer _player;
+  AudioPlayer _player;
 
   /// List of sound clips to play.
   final List<SoundClip>? soundClips;
@@ -48,7 +48,11 @@ class PlayerModel extends ChangeNotifier {
 
   /// Prepare player for playing from current playhead position.
   Future<void> prepare() async {
-    if (soundClips!.isEmpty) return;
+    if (soundClips!.isEmpty) {
+      _player.dispose();
+      _player = AudioPlayer();
+      return;
+    }
 
     await _player.setFilePath(
       soundClips!.first.path,