mucke/lib/domain/modules/managed_queue.dart
2021-10-02 19:23:41 +02:00

312 lines
8.9 KiB
Dart

import 'package:rxdart/rxdart.dart';
import '../../system/models/queue_item_model.dart';
import '../../system/models/song_model.dart';
import '../entities/queue_item.dart';
import '../entities/shuffle_mode.dart';
import '../entities/song.dart';
import '../repositories/music_data_repository.dart';
abstract class ManagedQueueInfo {
ValueStream<List<QueueItem>> get queueItemsStream;
ValueStream<List<Song>> get originalSongsStream;
ValueStream<List<Song>> get addedSongsStream;
}
class ManagedQueue implements ManagedQueueInfo {
ManagedQueue(this._musicDataRepository) : _queue = [];
// static final _log = FimberLog('ManagedQueue');
@override
ValueStream<List<Song>> get addedSongsStream => _addedSongsSubject.stream;
@override
ValueStream<List<Song>> get originalSongsStream => _originalSongsSubject.stream;
@override
ValueStream<List<QueueItem>> get queueItemsStream => _queueItemsSubject.stream;
final BehaviorSubject<List<QueueItem>> _queueItemsSubject = BehaviorSubject();
final BehaviorSubject<List<Song>> _originalSongsSubject = BehaviorSubject();
final BehaviorSubject<List<Song>> _addedSongsSubject = BehaviorSubject();
List<Song> get queue => _queue.map((e) => e.song).toList();
List<QueueItem> get queueItemList => _queue;
final MusicDataInfoRepository _musicDataRepository;
// this resembles the queue in AudioPlayer
// QueueItems are needed to determine the original position of the current song
List<QueueItem> _queue;
List<Song> _originalSongs = [];
List<Song> _addedSongs = [];
void addToQueue(Song song) {
_addedSongs.add(song);
_addedSongsSubject.add(_addedSongs);
final queueItem = QueueItemModel(
song as SongModel,
originalIndex: _addedSongs.length - 1,
type: QueueItemType.added,
);
_queue.add(queueItem);
_queueItemsSubject.add(_queue);
}
void initQueue(List<QueueItem> queueItems, List<Song> originalSongs, List<Song> addedSongs) {
// no push on subject here to not trigger persistence?
_queue = queueItems;
_originalSongs = originalSongs;
_addedSongs = addedSongs;
}
void insertIntoQueue(Song song, int index) {
_addedSongs.add(song);
_addedSongsSubject.add(_addedSongs);
final queueItem = QueueItemModel(
song as SongModel,
originalIndex: _addedSongs.length - 1,
type: QueueItemType.added,
);
_queue.insert(index, queueItem);
_queueItemsSubject.add(_queue);
}
void moveQueueItem(int oldIndex, int newIndex) {
final queueItem = _queue.removeAt(oldIndex);
_queue.insert(newIndex, queueItem);
_queueItemsSubject.add(_queue);
}
void removeQueueIndex(int index) {
final queueItem = _queue[index];
// if a song is removed from the queue, it should not pop up again when reshuffling
if (queueItem.type == QueueItemType.added) {
_addedSongs.removeAt(queueItem.originalIndex);
_addedSongsSubject.add(_addedSongs);
} else if (queueItem.type == QueueItemType.standard) {
_originalSongs.removeAt(queueItem.originalIndex);
_originalSongsSubject.add(_originalSongs);
}
for (int i = 0; i < queueItemList.length; i++) {
if (queueItemList[i].type == queueItem.type &&
queueItemList[i].originalIndex > queueItem.originalIndex) {
queueItemList[i] = QueueItemModel(
queueItemList[i].song as SongModel,
originalIndex: queueItemList[i].originalIndex - 1,
type: queueItemList[i].type,
);
}
}
_queue.removeAt(index);
_queueItemsSubject.add(_queue);
}
// so this is the motivation behind all the original/added songs and queueitems:
// to regenerate the original queue, we need the the original song list
// and the position of the current song in this original song list
Future<int> reshuffleQueue(
ShuffleMode shuffleMode,
int currentIndex,
) async {
final songs = _originalSongs.cast<Song>() + _addedSongs;
final currentQueueItem = _queue[currentIndex];
int originalIndex = currentQueueItem.originalIndex;
if (currentQueueItem.type == QueueItemType.added) {
originalIndex += _originalSongs.length;
}
return await _generateQueue(shuffleMode, songs, originalIndex);
}
/// Generate a queue from [songs] according to [shuffleMode].
Future<int> generateQueue(
ShuffleMode shuffleMode,
List<Song> songs,
int startIndex,
) async {
_originalSongs = songs;
_originalSongsSubject.add(_originalSongs);
_addedSongs = [];
_addedSongsSubject.add(_addedSongs);
return await _generateQueue(shuffleMode, songs, startIndex);
}
/// Update songs contained in queue. Return true if any song was changed.
bool updateSongs(Map<String, Song> songs) {
bool changed = false;
for (int i = 0; i < _queue.length; i++) {
if (songs.containsKey(_queue[i].song.path)) {
_queue[i] = (_queue[i] as QueueItemModel).copyWith(
song: songs[_queue[i].song.path]! as SongModel,
);
changed = true;
}
}
for (int i = 0; i < _originalSongs.length; i++) {
if (songs.containsKey(_originalSongs[i].path)) {
_originalSongs[i] = songs[_originalSongs[i].path]!;
}
}
for (int i = 0; i < _addedSongs.length; i++) {
if (songs.containsKey(_addedSongs[i].path)) {
_addedSongs[i] = songs[_addedSongs[i].path]!;
}
}
return changed;
}
Future<int> _generateQueue(
ShuffleMode shuffleMode,
List<Song> songs,
int startIndex,
) async {
switch (shuffleMode) {
case ShuffleMode.none:
return _generateNormalQueue(songs, startIndex);
case ShuffleMode.standard:
return _generateShuffleQueue(songs, startIndex);
case ShuffleMode.plus:
return await _generateShufflePlusQueue(songs, startIndex);
}
}
int _generateNormalQueue(List<Song> songs, int startIndex) {
_queue = List<QueueItem>.generate(
songs.length,
(i) => QueueItemModel(
songs[i] as SongModel,
originalIndex: i,
),
);
_queueItemsSubject.add(_queue);
return startIndex;
}
int _generateShuffleQueue(List<Song> songs, int startIndex) {
final List<QueueItem> queue = List<QueueItem>.generate(
songs.length,
(i) => QueueItemModel(
songs[i] as SongModel,
originalIndex: i,
),
);
queue.removeAt(startIndex);
queue.shuffle();
final first = QueueItemModel(
songs[startIndex] as SongModel,
originalIndex: startIndex,
);
_queue = [first] + queue.cast();
_queueItemsSubject.add(_queue);
return 0;
}
Future<int> _generateShufflePlusQueue(List<Song> songs, int startIndex) async {
final List<QueueItem> queue = await _getQueueItemWithLinks(
songs[startIndex],
startIndex,
);
// determine the start index in cases where the "first song" has predecessors
int newStartIndex = 0;
for (final qi in queue) {
if (qi.song.path == songs[startIndex].path) {
break;
} else {
newStartIndex++;
}
}
final List<int> indices = [];
final List<int> filteredIndices = [];
// filter mediaitem list
for (var i = 0; i < songs.length; i++) {
if (i != startIndex && !songs[i].blocked) {
indices.addAll(List.generate(songs[i].likeCount + 1, (_) => i));
} else if (i != startIndex) {
filteredIndices.add(i);
}
}
indices.shuffle();
for (final index in indices) {
final Song song = songs[index];
queue.addAll(await _getQueueItemWithLinks(song, index));
}
_queue = queue;
_queueItemsSubject.add(_queue);
return newStartIndex;
}
// TODO: naming things is hard
Future<List<QueueItem>> _getQueueItemWithLinks(
Song song,
int index,
) async {
final List<QueueItem> queueItems = [];
final predecessors = await _getPredecessors(song);
final successors = await _getSuccessors(song);
for (final p in predecessors) {
queueItems.add(QueueItemModel(
p as SongModel,
originalIndex: index,
type: QueueItemType.predecessor,
));
}
queueItems.add(QueueItemModel(
song as SongModel,
originalIndex: index,
));
for (final s in successors) {
queueItems.add(QueueItemModel(
s as SongModel,
originalIndex: index,
type: QueueItemType.successor,
));
}
return queueItems;
}
Future<List<Song>> _getPredecessors(Song song) async {
final List<Song> songs = [];
Song currentSong = song;
while (currentSong.previous != '') {
currentSong = await _musicDataRepository.getSongByPath(currentSong.previous);
songs.add(currentSong);
}
return songs.reversed.toList();
}
Future<List<Song>> _getSuccessors(Song song) async {
final List<Song> songs = [];
Song currentSong = song;
while (currentSong.next != '') {
currentSong = await _musicDataRepository.getSongByPath(currentSong.next);
songs.add(currentSong);
}
return songs.toList();
}
}