TTMusic/entry/src/main/ets/controller/CastController.ets

/*
 * Copyright (c) 2025 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { common } from '@kit.AbilityKit';
import { avSession } from '@kit.AVSessionKit';
import { BusinessError } from '@kit.BasicServicesKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
import { fileIo } from '@kit.CoreFileKit';
import { media } from '@kit.MediaKit';
import { fileUri } from '@kit.CoreFileKit';
import { VideoItem } from '../viewmodel/VideoItem';

const TAG = 'heanup CastController';

/**
 * 投播控制器回调接口
 */
export interface CastControllerCallbacks {
  onPlayNext?: () => void;
  onPlayPrevious?: () => void;
  onPositionChanged?: (position: number) => void;
  onDurationChanged?: (duration: number) => void;
}

/**
 * 投播控制器 - 参考官方 AudioCast-master 示例实现
 * 负责管理音频投播的完整生命周期
 */
export class CastController {
  // 投播控制器实例
  private avCastController: avSession.AVCastController | undefined = undefined;
  private context: common.UIAbilityContext | undefined = undefined;

  // 歌曲列表和当前索引
  private songList: VideoItem[] = [];
  private musicIndex: number = 0;

  // 播放状态（使用 @Track 让 UI 可观察）
  @Track state: avSession.PlaybackState = avSession.PlaybackState.PLAYBACK_STATE_INITIAL;
  @Track elapsedTime: number = 0;
  @Track duration: number = 0;
  @Track volume: number = 0;
  @Track isCastPlaying: boolean = false;

  // 文件描述符引用，避免被垃圾回收
  private castFile: fileIo.File | undefined = undefined;
  private isSwitchingTrack: boolean = false;
  private hasHandledEnd: boolean = false;

  // 回调函数
  private onPlayNext: (() => void) | undefined = undefined;
  private onPlayPrevious: (() => void) | undefined = undefined;
  private onPositionChanged: ((position: number) => void) | undefined = undefined;
  private onDurationChanged: ((duration: number) => void) | undefined = undefined;

  constructor(avCastController: avSession.AVCastController | undefined) {
    this.avCastController = avCastController;
    this.context = AppStorage.get('context') as common.UIAbilityContext;
  }

  /**
   * 设置回调函数
   */
  public setCallbacks(callbacks: CastControllerCallbacks): void {
    this.onPlayNext = callbacks.onPlayNext;
    this.onPlayPrevious = callbacks.onPlayPrevious;
    this.onPositionChanged = callbacks.onPositionChanged;
    this.onDurationChanged = callbacks.onDurationChanged;
  }

  /**
   * 初始化投播会话
   * @param songList 歌曲列表
   * @param musicIndex 当前歌曲索引
   * @param startPosition 开始播放位置（毫秒）
   * @param videoUrl 当前歌曲的视频URL（用于流媒体判断）
   */
  public async initAVCast(
    songList: VideoItem[],
    musicIndex: number,
    startPosition: number,
    videoUrl: string,
    duration?: number
  ): Promise<void> {
   console.info( TAG, '========== initAVCast 开始 ==========');
   console.info( TAG, `initAVCast 参数: songList.length=${songList.length}, musicIndex=${musicIndex}, startPosition=${startPosition}, videoUrl=${videoUrl}`);

    this.songList = songList;
    this.musicIndex = musicIndex;

   console.info( TAG, '✅ 更新内部状态完成');

    try {
      await this.setCastResource(startPosition, videoUrl, duration);
     console.info( TAG, '✅ setCastResource 完成');
    } catch (error) {
      let errorMsg = error instanceof Error ? error.message : String(error);
      console.error( TAG, `❌ setCastResource 失败: ${errorMsg}`);
      // 不再 throw，而是记录错误
      this.isCastPlaying = false;
    }

    try {
      let currentItem = await this.avCastController?.getCurrentItem();
      if (currentItem?.description?.duration) {
        this.duration = currentItem.description.duration;
       console.info( TAG, `✅ 获取歌曲时长成功: ${this.duration}ms`);
      }
    } catch (error) {
      let errorMsg = error instanceof Error ? error.message : String(error);
      console.error( TAG, `⚠️ getCurrentItem失败: ${errorMsg}`);
    }

    this.setAVCastCallback();
   console.info( TAG, '========== initAVCast 完成 ==========');
  }

  /**
   * 设置并准备投播资源
   * @param startPosition 开始播放位置（毫秒）
   * @param videoUrl 视频URL
   */
  public async setCastResource(startPosition: number, videoUrl: string, duration?: number): Promise<void> {
   console.info( TAG, '========== setCastResource 开始 ==========');

    if (!this.avCastController || !this.context) {
      console.error( TAG, '❌ avCastController 或 context 未初始化');
      return;
    }
   console.info( TAG, '✅ avCastController 和 context 检查通过');

    let songItem: VideoItem = this.songList[this.musicIndex];
   console.info( TAG, `准备投播歌曲: ${songItem.name}, filePath: ${songItem.filePath}`);
   console.info( TAG, `videoUrl: ${videoUrl}`);

    // 关闭之前的文件描述符
    if (this.castFile) {
      try {
        fileIo.closeSync(this.castFile);
       console.info( TAG, '✅ 关闭之前的文件描述符');
      } catch (error) {
        hilog.warn(0x0000, TAG, `⚠️ 关闭文件描述符失败: ${error}`);
      }
    }

    let playItem: avSession.AVQueueItem;

    try {
      // 判断是否是流媒体
      let isStreaming = this.isUrl(videoUrl);
     console.info( TAG, `是否流媒体: ${isStreaming}`);

      let description: avSession.AVMediaDescription = {
        assetId: songItem.filePath,
        title: songItem.name,
        subtitle: 'audio',
        artist: songItem.artist || '',
        mediaType: 'AUDIO',
        mediaSize: songItem.videoSize || 0,
        startPosition: startPosition,
        duration: duration || 0,
      };
     console.info( TAG, '✅ 创建 AVMediaDescription 成功');

      if (isStreaming) {
        // 流媒体使用 mediaUri
        description.mediaUri = videoUrl;
       console.info( TAG, `✅ 使用流媒体地址投播: ${videoUrl}`);
      } else {
        // 本地文件使用 fdSrc
        // let uri = fileUri.getUriFromPath(songItem.filePath);
        //console.info( TAG, `文件URI: ${uri}`);

        this.castFile = fileIo.openSync(songItem.filePath, fileIo.OpenMode.READ_ONLY);
       console.info( TAG, `✅ 打开文件成功, fd: ${this.castFile.fd}`);

        let fdSrc: media.AVFileDescriptor = { fd: this.castFile.fd };
        description.fdSrc = fdSrc;
        console.info( TAG, `✅ 使用本地文件投播: ${songItem.filePath}, fd: ${this.castFile.fd}`);
      }

      playItem = {
        itemId: this.musicIndex,
        description: description
      };
      console.info( TAG, '✅ 创建 AVQueueItem 成功');

      // 先 prepare 再 start
      console.info( TAG, '开始调用 prepare...');
      await this.avCastController.prepare(playItem);
      console.info(TAG, '✅ 投播 prepare 成功');

      console.info( TAG, '开始调用 start...');
      await this.avCastController.start(playItem);
      console.info( TAG, '✅ 投播 start 成功');

      // 设置投播状态为 true
      this.isCastPlaying = true;
      this.isSwitchingTrack = false;
      this.hasHandledEnd = false;
      this.elapsedTime = startPosition;
      this.onPositionChanged?.(this.elapsedTime);
      if (typeof description.duration === 'number' && description.duration > 0) {
        this.duration = description.duration;
        this.onDurationChanged?.(this.duration);
      }
      console.info(TAG, '✅✅✅ 投播启动成功，isCastPlaying=true ✅✅✅');

    } catch (err) {
      let errorMsg = err instanceof Error ? err.message : String(err);
      console.error( TAG, `❌❌❌ 投播准备失败: ${errorMsg}`);
      this.isCastPlaying = false;
    }

    console.info(TAG, '========== setCastResource 完成 ==========');
  }

  /**
   * 判断是否是 URL
   */
  private isUrl(str: string): boolean {
    if (!str) {
      return false;
    }
    if (str.startsWith('http://') || str.startsWith('https://') ||
        str.startsWith('rtmp://') || str.startsWith('rtsp://') ||
        str.startsWith('rtp://') || str.startsWith('mms://')) {
      return true;
    }
    return false;
  }

  /**
   * 设置投播状态变化监听器
   */
  setAVCastCallback(): void {
   console.info( TAG, '开始设置投播监听器');
    this.unregisterCastListener();

    try {
      // 1. 监听播放状态变化
      this.avCastController?.on('playbackStateChange', ['state'], async (playbackState: avSession.AVPlaybackState) => {
       console.info( TAG, `[state回调] state=${playbackState.state}`);
        if (playbackState.state) {
          this.state = playbackState.state;
          // 更新 isCastPlaying 状态
          if (playbackState.state === avSession.PlaybackState.PLAYBACK_STATE_PLAY) {
            this.isCastPlaying = true;
           console.info( TAG, '[state回调] 设置 isCastPlaying=true');
          } else if (playbackState.state === avSession.PlaybackState.PLAYBACK_STATE_PAUSE) {
           console.info( TAG, '[state回调] 暂停状态');
            // 暂停时保持 isCastPlaying 不变
          } else if (playbackState.state === avSession.PlaybackState.PLAYBACK_STATE_STOP) {
           console.info( TAG, '[state回调] 停止状态，保持 isCastPlaying=' + this.isCastPlaying);
            // STOP 状态不改变 isCastPlaying，确保播放完成时继续播放下一首
            if (this.shouldAutoPlayNextOnStop()) {
             console.info(TAG, '[state回调] STOP 且接近播放结束，触发下一首');
              this.hasHandledEnd = true;
              this.onPlayNext?.();
            }
          }
        }
      });

      // 2. 监听位置变化
      this.avCastController?.on('playbackStateChange', ['position'], (playbackState: avSession.AVPlaybackState) => {
        if (playbackState.position && playbackState.position.elapsedTime !== undefined) {
          this.elapsedTime = playbackState.position.elapsedTime;
          // 只在每10秒输出一次日志，避免日志过多
          if (this.elapsedTime % 10000 < 1000) {
           console.info( TAG, `[position回调] elapsedTime=${this.elapsedTime}ms`);
          }
          // 触发回调
          this.onPositionChanged?.(this.elapsedTime);
        }
      });

      // 3. 监听时长变化
      this.avCastController?.on('playbackStateChange', ['extras'], (playbackState: avSession.AVPlaybackState) => {
        const duration = playbackState?.extras?.duration;
        if (typeof duration === 'number') {
          this.duration = duration;
         console.info( TAG, `[extras回调] duration=${this.duration}ms`);
          // 触发回调
          this.onDurationChanged?.(this.duration);
        }
      });

      // 4. 监听进度调节完成事件
      this.avCastController?.on('seekDone', (position: number) => {
        this.elapsedTime = position;
       console.info( TAG, `[seekDone回调] position=${position}ms`);
        this.onPositionChanged?.(this.elapsedTime);
      });

      // 5. 监听所有状态变化（调试用）
      this.avCastController?.on('playbackStateChange', 'all', (playbackState: avSession.AVPlaybackState) => {
       console.info( TAG, `[all回调] 完整状态: ${JSON.stringify(playbackState)}`);
      });

      // 6. 监听播放完成事件 ⭐ 关键
      this.avCastController?.on('endOfStream', () => {
       console.info( TAG, '⭐⭐⭐ [endOfStream回调] 播放完成，触发下一首 ⭐⭐⭐');
        console.info( TAG, `[endOfStream回调] 当前 isCastPlaying=${this.isCastPlaying}`);
        // 确保 isCastPlaying 在播放完成时保持为 true，以便下一首能继续投播
        this.isCastPlaying = true;
        console.info( TAG, `[endOfStream回调] 强制设置 isCastPlaying=true`);
        this.hasHandledEnd = true;
        this.onPlayNext?.();
      });

      this.avCastController?.on('playNext', () => {
       console.info( TAG, '⭐⭐⭐ [playNext回调] 触发下一首 ⭐⭐⭐');
        this.onPlayNext?.();
      });

      this.avCastController?.on('playPrevious', () => {
       console.info( TAG, '⭐⭐⭐ [playPrevious回调] 触发上一首 ⭐⭐⭐');
        this.onPlayPrevious?.();
      });

      // 6. 监听错误事件
      this.avCastController?.on('error', (error: BusinessError) => {
        console.error( TAG, `[error回调] 投播错误: code=${error.code}, message=${error.message}`);
        this.isCastPlaying = false;
      });

     console.info( TAG, '✅ 所有监听器设置完成');
    } catch (error) {
      console.error( TAG, `❌ 设置监听器失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 播放
   */
  public async setPlaying(): Promise<void> {
    try {
      let avCommand: avSession.AVCastControlCommand = { command: 'play' };
      await this.avCastController?.sendControlCommand(avCommand);
     console.info( TAG, '发送 play 命令成功');
    } catch (error) {
      console.error( TAG, `play 命令失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 暂停
   */
  public async setPause(): Promise<void> {
    try {
      let avCommand: avSession.AVCastControlCommand = { command: 'pause' };
      await this.avCastController?.sendControlCommand(avCommand);
     console.info( TAG, '发送 pause 命令成功');
    } catch (error) {
      console.error( TAG, `pause 命令失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 停止
   */
  public async setStop(): Promise<void> {
    try {
      let avCommand: avSession.AVCastControlCommand = { command: 'stop' };
      await this.avCastController?.sendControlCommand(avCommand);
     console.info( TAG, '发送 stop 命令成功');
    } catch (error) {
      console.error( TAG, `stop 命令失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 跳转
   */
  public async seek(timeMS: number): Promise<void> {
    try {
      let avCommand: avSession.AVCastControlCommand = { command: 'seek', parameter: timeMS };
      await this.avCastController?.sendControlCommand(avCommand);
     console.info( TAG, `发送 seek 命令成功: ${timeMS}ms`);
    } catch (error) {
      console.error( TAG, `seek 命令失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 设置音量
   */
  public async setVolume(volume: number): Promise<void> {
    try {
      let avCommand: avSession.AVCastControlCommand = { command: 'setVolume', parameter: volume };
      await this.avCastController?.sendControlCommand(avCommand);
     console.info( TAG, `发送 setVolume 命令成功: ${volume}`);
    } catch (error) {
      console.error( TAG, `setVolume 命令失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 设置循环模式
   */
  public async setLoopMode(mode: number): Promise<void> {
    try {
      let avCommand: avSession.AVCastControlCommand = { command: 'setLoopMode', parameter: mode };
      await this.avCastController?.sendControlCommand(avCommand);
     console.info( TAG, `发送 setLoopMode 命令成功: ${mode}`);
    } catch (error) {
      console.error( TAG, `setLoopMode 命令失败: ${JSON.stringify(error)}`);
    }
  }

  /**
   * 播放下一首
   * @param songList 最新的歌曲列表
   * @param musicIndex 最新的歌曲索引
   * @param videoUrl 最新的视频URL
   */
  public async playNext(songList: VideoItem[], musicIndex: number, videoUrl: string, duration?: number): Promise<void> {
   console.info( TAG, `playNext: 传入索引=${musicIndex}, 当前内部索引=${this.musicIndex}`);

    // 更新内部状态
    this.songList = songList;
    this.musicIndex = musicIndex;
    this.isSwitchingTrack = true;

    // 直接切换资源，避免 stop 导致投播会话被终止
    try {
      await this.setCastResource(0, videoUrl, duration);
     console.info( TAG, 'playNext: prepare 和 start 完成');
    } finally {
      this.isSwitchingTrack = false;
    }
  }

  /**
   * 播放上一首
   * @param songList 最新的歌曲列表
   * @param musicIndex 最新的歌曲索引
   * @param videoUrl 最新的视频URL
   */
  public async playPrevious(songList: VideoItem[], musicIndex: number, videoUrl: string, duration?: number): Promise<void> {
   console.info( TAG, `playPrevious: 传入索引=${musicIndex}, 当前内部索引=${this.musicIndex}`);

    // 更新内部状态
    this.songList = songList;
    this.musicIndex = musicIndex;
    this.isSwitchingTrack = true;

    // 直接切换资源，避免 stop 导致投播会话被终止
    try {
      await this.setCastResource(0, videoUrl, duration);
     console.info( TAG, 'playPrevious: prepare 和 start 完成');
    } finally {
      this.isSwitchingTrack = false;
    }
  }

  /**
   * 获取当前索引
   */
  public getCurrentIndex(): number {
    return this.musicIndex;
  }

  /**
   * 获取是否正在投播
   */
  public getIsCastPlaying(): boolean {
    return this.isCastPlaying;
  }

  private shouldAutoPlayNextOnStop(): boolean {
    if (this.isSwitchingTrack || this.hasHandledEnd) {
      return false;
    }
    if (this.duration <= 0 || this.elapsedTime <= 0) {
      return false;
    }
    return (this.duration - this.elapsedTime) <= 1500;
  }

  /**
   * 释放投播控制器资源
   */
  public async releaseAVCast(): Promise<void> {
    try {
      await this.avCastController?.release();
     console.info( TAG, '释放投播控制器成功');
    } catch (error) {
      console.error( TAG, `释放投播控制器失败: ${JSON.stringify(error)}`);
    }

    // 关闭文件描述符
    if (this.castFile) {
      try {
        fileIo.closeSync(this.castFile);
        this.castFile = undefined;
       console.info( TAG, '关闭文件描述符成功');
      } catch (error) {
        console.error( TAG, `关闭文件描述符失败: ${error}`);
      }
    }

    this.isCastPlaying = false;
    this.unregisterCastListener();
  }

  /**
   * 移除所有监听器
   */
  public unregisterCastListener(): void {
    try {
      this.avCastController?.off('playbackStateChange');
      this.avCastController?.off('seekDone');
      this.avCastController?.off('playNext');
      this.avCastController?.off('playPrevious');
      this.avCastController?.off('endOfStream');
      this.avCastController?.off('error');
     console.info( TAG, '移除监听器成功');
    } catch (error) {
      console.error( TAG, `移除监听器失败: ${JSON.stringify(error)}`);
    }
  }
}