import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

class PAGView extends StatefulWidget {
  /// 宽高，不建议不设置
  final double? width;
  final double? height;

  /// 二进制动画数据
  final Uint8List? bytesData;

  /// 网络资源，动画链接
  final String? url;

  /// flutter动画资源路径
  final String? assetName;

  /// asset package
  final String? package;

  /// 初始化时播放进度
  final double initProgress;

  /// 初始化后自动播放
  final bool autoPlay;

  /// 循环次数
  final int repeatCount;

  /// 初始化完成
  final PAGCallback? onInit;

  /// Notifies the start of the animation.
  final PAGCallback? onAnimationStart;

  /// Notifies the end of the animation.
  final PAGCallback? onAnimationEnd;

  /// Notifies the cancellation of the animation.
  final PAGCallback? onAnimationCancel;

  /// Notifies the repetition of the animation.
  final PAGCallback? onAnimationRepeat;

  /// 加载失败时的默认控件构造器
  final Widget Function(BuildContext context)? defaultBuilder;

  static const int REPEAT_COUNT_LOOP = -1; //无限循环
  static const int REPEAT_COUNT_DEFAULT = 1; //默认仅播放一次

  const PAGView.network(
    this.url, {
    this.width,
    this.height,
    this.repeatCount = REPEAT_COUNT_DEFAULT,
    this.initProgress = 0,
    this.autoPlay = false,
    this.onInit,
    this.onAnimationStart,
    this.onAnimationEnd,
    this.onAnimationCancel,
    this.onAnimationRepeat,
    this.defaultBuilder,
    Key? key,
  })  : this.bytesData = null,
        this.assetName = null,
        this.package = null,
        super(key: key);

  const PAGView.asset(
    this.assetName, {
    this.width,
    this.height,
    this.repeatCount = REPEAT_COUNT_DEFAULT,
    this.initProgress = 0,
    this.autoPlay = false,
    this.package,
    this.onInit,
    this.onAnimationStart,
    this.onAnimationEnd,
    this.onAnimationCancel,
    this.onAnimationRepeat,
    this.defaultBuilder,
    Key? key,
  })  : this.bytesData = null,
        this.url = null,
        super(key: key);

  const PAGView.bytes(
    this.bytesData, {
    this.width,
    this.height,
    this.repeatCount = REPEAT_COUNT_DEFAULT,
    this.initProgress = 0,
    this.autoPlay = false,
    this.package,
    this.onInit,
    this.onAnimationStart,
    this.onAnimationEnd,
    this.onAnimationCancel,
    this.onAnimationRepeat,
    this.defaultBuilder,
    Key? key,
  })  : this.url = null,
        this.assetName = null,
        super(key: key);

  @override
  PAGViewState createState() => PAGViewState();
}

class PAGViewState extends State<PAGView> {
  bool _hasLoadTexture = false;
  int _textureId = -1;

  double rawWidth = 0;
  double rawHeight = 0;

  static const double defaultSize = 50;

  // 原生接口
  static const String _nativeInit = 'initPag';
  static const String _nativeRelease = 'release';
  static const String _nativeStart = 'start';
  static const String _nativeStop = 'stop';
  static const String _nativePause = 'pause';
  static const String _nativeSetProgress = 'setProgress';
  static const String _nativeGetPointLayer = 'getLayersUnderPoint';
  static const String _nativeEnableCache = "enableCache";
  static const String _nativeSetCacheSize = "setCacheSize";
  static const String _nativeEnableMultiThread = "enableMultiThread";

  // 参数
  static const String _argumentTextureId = 'textureId';
  static const String _argumentAssetName = 'assetName';
  static const String _argumentPackage = 'package';
  static const String _argumentUrl = 'url';
  static const String _argumentBytes = 'bytesData';
  static const String _argumentRepeatCount = 'repeatCount';
  static const String _argumentInitProgress = 'initProgress';
  static const String _argumentAutoPlay = 'autoPlay';
  static const String _argumentWidth = 'width';
  static const String _argumentHeight = 'height';
  static const String _argumentPointX = 'x';
  static const String _argumentPointY = 'y';
  static const String _argumentProgress = 'progress';
  static const String _argumentEvent = 'PAGEvent';
  static const String _argumentCacheEnabled = "cacheEnabled";
  static const String _argumentCacheSize = "cacheSize";
  static const String _argumentMultiThreadEnabled = "multiThreadEnabled";

  // 监听该函数
  static const String _playCallback = 'PAGCallback';
  static const String _eventStart = 'onAnimationStart';
  static const String _eventEnd = 'onAnimationEnd';
  static const String _eventCancel = 'onAnimationCancel';
  static const String _eventRepeat = 'onAnimationRepeat';
  static const String _eventUpdate = 'onAnimationUpdate';

  // 回调监听
  static MethodChannel _channel = (const MethodChannel('flutter_pag_plugin')
    ..setMethodCallHandler((result) {
      if (result.method == _playCallback) {
        callbackHandlers[result.arguments[_argumentTextureId]]?.call(result.arguments[_argumentEvent]);
      }

      return Future<dynamic>.value();
    }));

  static Map<int, Function(String event)?> callbackHandlers = {};

  @override
  void initState() {
    super.initState();
    newTexture();
  }

  // 初始化
  void newTexture() async {
    int repeatCount = widget.repeatCount <= 0 && widget.repeatCount != PAGView.REPEAT_COUNT_LOOP ? PAGView.REPEAT_COUNT_DEFAULT : widget.repeatCount;
    double initProcess = widget.initProgress < 0 ? 0 : widget.initProgress;

    try {
      dynamic result =
          await _channel.invokeMethod(_nativeInit, {_argumentAssetName: widget.assetName, _argumentPackage: widget.package, _argumentUrl: widget.url, _argumentBytes: widget.bytesData, _argumentRepeatCount: repeatCount, _argumentInitProgress: initProcess, _argumentAutoPlay: widget.autoPlay});
      if (result is Map) {
        _textureId = result[_argumentTextureId];
        rawWidth = result[_argumentWidth] ?? 0;
        rawHeight = result[_argumentHeight] ?? 0;
      }
      if (mounted) {
        setState(() {
          _hasLoadTexture = true;
        });
        widget.onInit?.call();
      } else {
        _channel.invokeMethod(_nativeRelease, {_argumentTextureId: _textureId});
      }
    } catch (e) {
      print('PAGViewState error: $e');
    }

    // 事件回调
    if (_textureId >= 0) {
      var events = <String, PAGCallback?>{
        _eventStart: widget.onAnimationStart,
        _eventEnd: widget.onAnimationEnd,
        _eventCancel: widget.onAnimationCancel,
        _eventRepeat: widget.onAnimationRepeat,
      };
      callbackHandlers[_textureId] = (event) {
        events[event]?.call();
      };
    }
  }

  /// 开始
  void start() {
    if (!_hasLoadTexture) {
      return;
    }
    _channel.invokeMethod(_nativeStart, {_argumentTextureId: _textureId});
  }

  /// 停止
  void stop() {
    if (!_hasLoadTexture) {
      return;
    }
    _channel.invokeMethod(_nativeStop, {_argumentTextureId: _textureId});
  }

  /// 暂停
  void pause() {
    if (!_hasLoadTexture) {
      return;
    }
    _channel.invokeMethod(_nativePause, {_argumentTextureId: _textureId});
  }

  /// 设置进度
  void setProgress(double progress) {
    if (!_hasLoadTexture) {
      return;
    }
    _channel.invokeMethod(_nativeSetProgress, {_argumentTextureId: _textureId, _argumentProgress: progress});
  }

  /// 获取某一位置的图层
  Future<List<String>> getLayersUnderPoint(double x, double y) async {
    if (!_hasLoadTexture) {
      return [];
    }
    return (await _channel.invokeMethod(_nativeGetPointLayer, {_argumentTextureId: _textureId, _argumentPointX: x, _argumentPointY: y}) as List).map((e) => e.toString()).toList();
  }

  @override
  Widget build(BuildContext context) {
    if (_hasLoadTexture) {
      return SizedBox(
        width: widget.width ?? (rawWidth / 2),
        height: widget.height ?? (rawHeight / 2),
        child: Texture(textureId: _textureId),
      );
    } else {
      return widget.defaultBuilder?.call(context) ??
          SizedBox(
            width: widget.width ?? defaultSize,
            height: widget.height ?? defaultSize,
          );
    }
  }

  @override
  void dispose() {
    super.dispose();
    _channel.invokeMethod(_nativeRelease, {_argumentTextureId: _textureId});
    callbackHandlers.remove(_textureId);
  }
}

typedef PAGCallback = void Function();

// PAG设置
class PAG {
  // 是否开启缓存，默认true
  static void enableCache(bool enable) {
    PAGViewState._channel.invokeMethod(PAGViewState._nativeEnableCache, {PAGViewState._argumentCacheEnabled: enable});
  }

  // 是否多线程加载和释放资源，默认true
  static void enableMultiThread(bool enable) {
    PAGViewState._channel.invokeMethod(PAGViewState._nativeEnableMultiThread, {PAGViewState._argumentMultiThreadEnabled: enable});
  }

  // 设置缓存数量，默认10
  static void setCacheSize(int size) {
    PAGViewState._channel.invokeMethod(PAGViewState._nativeSetCacheSize, {PAGViewState._argumentCacheSize: size});
  }
}