import 'dart:async';

import 'package:aves/model/entry.dart';
import 'package:aves/model/settings/settings.dart';
import 'package:aves/utils/change_notifier.dart';
import 'package:aves/widgets/common/video/video.dart';
import 'package:fijkplayer/fijkplayer.dart';
import 'package:flutter/material.dart';

class IjkPlayerAvesVideoController extends AvesVideoController {
  FijkPlayer _instance;
  final List<StreamSubscription> _subscriptions = [];
  final StreamController<FijkValue> _valueStreamController = StreamController.broadcast();
  final AChangeNotifier _playFinishNotifier = AChangeNotifier();

  Stream<FijkValue> get _valueStream => _valueStreamController.stream;

  IjkPlayerAvesVideoController() {
    _instance = FijkPlayer();

    // FFmpeg options
    // cf https://github.com/Bilibili/ijkplayer/blob/master/ijkmedia/ijkplayer/ff_ffplay_options.h
    // cf https://www.jianshu.com/p/843c86a9e9ad

    final option = FijkOption();
    // `fastseek`: enable fast, but inaccurate seeks for some formats
    option.setFormatOption('fflags', 'fastseek');
    // `enable-accurate-seek`: enable accurate seek, default: 0, in [0, 1]
    option.setPlayerOption('enable-accurate-seek', 1);
    // `framedrop`: drop frames when cpu is too slow, default: 0, in [-1, 120]
    option.setPlayerOption('framedrop', 5);

    final hwAccel = settings.isVideoHardwareAccelerationEnabled ? 1 : 0;
    // `mediacodec-all-videos`: MediaCodec: enable all videos, default: 0, in [0, 1]
    // TODO TLAD enabling `mediacodec-all-videos` randomly fails to render some videos, e.g. MP2TS/h264(HDPR)
    option.setPlayerOption('mediacodec-all-videos', hwAccel);

    // option.setPlayerOption('analyzemaxduration', 200 * 1024);
    // option.setPlayerOption('analyzeduration', 200 * 1024);
    // option.setPlayerOption('probesize', 1024 * 1024);

    // TODO TLAD check looping
    // option.setPlayerOption('loop', 42);

    _instance.applyOptions(option);

    _instance.addListener(_onValueChanged);
    _subscriptions.add(_valueStream.where((value) => value.completed).listen((_) => _playFinishNotifier.notifyListeners()));
  }

  @override
  void dispose() {
    _instance.removeListener(_onValueChanged);
    _valueStreamController.close();
    _subscriptions
      ..forEach((sub) => sub.cancel())
      ..clear();
    _instance.release();
  }

  void _onValueChanged() => _valueStreamController.add(_instance.value);

  // enable autoplay, even when seeking on uninitialized player, otherwise the texture is not updated
  // as a workaround, pausing after a brief duration is possible, but fiddly
  @override
  Future<void> setDataSource(String uri) => _instance.setDataSource(uri, autoPlay: true);

  @override
  Future<void> refreshVideoInfo() => null;

  @override
  Future<void> play() => _instance.start();

  @override
  Future<void> pause() => _instance.pause();

  @override
  Future<void> seekTo(int targetMillis) => _instance.seekTo(targetMillis);

  @override
  Future<void> seekToProgress(double progress) => _instance.seekTo((duration * progress).toInt());

  @override
  Listenable get playCompletedListenable => _playFinishNotifier;

  @override
  VideoStatus get status => _instance.state.toAves;

  @override
  Stream<VideoStatus> get statusStream => _valueStream.map((value) => value.state.toAves);

  @override
  bool get isVideoReady => _instance.value.videoRenderStart;

  @override
  Stream<bool> get isVideoReadyStream => _valueStream.map((value) => value.videoRenderStart);

  // we check whether video info is ready instead of checking for `noDatasource` status,
  // as the controller could also be uninitialized with the `pause` status
  // (e.g. when switching between video entries without playing them the first time)
  @override
  bool get isPlayable => _instance.isPlayable();

  @override
  int get duration => _instance.value.duration.inMilliseconds;

  @override
  int get currentPosition => _instance.currentPos.inMilliseconds;

  @override
  Stream<int> get positionStream => _instance.onCurrentPosUpdate.map((pos) => pos.inMilliseconds);

  @override
  Widget buildPlayerWidget(AvesEntry entry) => FijkView(
        player: _instance,
        panelBuilder: (player, data, context, viewSize, texturePos) => SizedBox(),
        color: Colors.transparent,
      );
}

extension ExtraIjkStatus on FijkState {
  VideoStatus get toAves {
    switch (this) {
      case FijkState.idle:
        return VideoStatus.idle;
      case FijkState.initialized:
        return VideoStatus.initialized;
      case FijkState.asyncPreparing:
        return VideoStatus.preparing;
      case FijkState.prepared:
        return VideoStatus.prepared;
      case FijkState.started:
        return VideoStatus.playing;
      case FijkState.paused:
        return VideoStatus.paused;
      case FijkState.completed:
        return VideoStatus.completed;
      case FijkState.stopped:
        return VideoStatus.stopped;
      case FijkState.end:
        return VideoStatus.disposed;
      case FijkState.error:
        return VideoStatus.error;
    }
    return VideoStatus.idle;
  }
}