import 'dart:async';

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

class FlutterIjkPlayerAvesVideoController extends AvesVideoController {
  IjkMediaController _instance;
  final List<StreamSubscription> _subscriptions = [];
  final AChangeNotifier _playFinishNotifier = AChangeNotifier();

  FlutterIjkPlayerAvesVideoController() {
    _instance = IjkMediaController();
    _subscriptions.add(_instance.playFinishStream.listen((_) => _playFinishNotifier.notifyListeners()));
  }

  @override
  void dispose() {
    _subscriptions
      ..forEach((sub) => sub.cancel())
      ..clear();
    _instance?.dispose();
  }

  // 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(DataSource.photoManagerUrl(uri), autoPlay: true);

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

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

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

  @override
  Future<void> seekTo(int targetMillis) => _instance.seekTo(targetMillis / 1000.0);

  @override
  Future<void> seekToProgress(double progress) => _instance.seekToProgress(progress);

  @override
  Listenable get playCompletedListenable => _playFinishNotifier;

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

  @override
  Stream<VideoStatus> get statusStream => _instance.ijkStatusStream.map((status) => status.toAves);

  // 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 => _videoInfo.hasData;

  @override
  bool get isVideoReady => _instance.textureId != null;

  @override
  Stream<bool> get isVideoReadyStream => _instance.textureIdStream.map((id) => id != null);

  // `videoInfo` is never null (even if `toString` prints `null`)
  // check presence with `hasData` instead
  VideoInfo get _videoInfo => _instance.videoInfo;

  @override
  int get duration => _videoInfo.durationMillis;

  @override
  int get currentPosition => _videoInfo.currentPositionMillis;

  @override
  Stream<int> get positionStream => _instance.videoInfoStream.map((info) => info.currentPositionMillis);

  @override
  Widget buildPlayerWidget(AvesEntry entry) => IjkPlayer(
        mediaController: _instance,
        controllerWidgetBuilder: (controller) => SizedBox.shrink(),
        statusWidgetBuilder: (context, controller, status) => SizedBox.shrink(),
        textureBuilder: (context, controller, info) {
          var id = controller.textureId;
          var child = id != null
              ? Texture(
                  textureId: id,
                )
              : Container(
                  color: Colors.black,
                );

          final degree = entry.rotationDegrees ?? 0;
          if (degree != 0) {
            child = RotatedBox(
              quarterTurns: degree ~/ 90,
              child: child,
            );
          }

          return Center(
            child: AspectRatio(
              aspectRatio: entry.displayAspectRatio,
              child: child,
            ),
          );
        },
        backgroundColor: Colors.transparent,
      );
}

extension ExtraVideoInfo on VideoInfo {
  int get durationMillis => duration == null ? null : (duration * 1000).toInt();

  int get currentPositionMillis => currentPosition == null ? null : (currentPosition * 1000).toInt();
}

extension ExtraIjkStatus on IjkStatus {
  VideoStatus get toAves {
    switch (this) {
      case IjkStatus.noDatasource:
        return VideoStatus.idle;
      case IjkStatus.preparing:
        return VideoStatus.preparing;
      case IjkStatus.prepared:
        return VideoStatus.prepared;
      case IjkStatus.playing:
        return VideoStatus.playing;
      case IjkStatus.pause:
        return VideoStatus.paused;
      case IjkStatus.complete:
        return VideoStatus.completed;
      case IjkStatus.disposed:
        return VideoStatus.disposed;
      case IjkStatus.setDatasourceFail:
      case IjkStatus.error:
        return VideoStatus.error;
    }
    return VideoStatus.idle;
  }
}