import BarkDetector from './barkDetector';

export default class AudioRecorder {
  constructor(options = {}) {
    this.recorder = wx.getRecorderManager();
    this.detector = new BarkDetector(options);
    this.isRecording = false;
    this.sampleRate = options.sampleRate || 16000;
    this.frameSize = options.frameSize || 8192;
    this.onUpdate = options.onUpdate || null;
    this.onError = options.onError || null;

    this._bindEvents();
  }

  _bindEvents() {
    this.recorder.onStart(() => {
      this.isRecording = true;
    });

    this.recorder.onStop(() => {
      this.isRecording = false;
    });

    this.recorder.onError((err) => {
      this.isRecording = false;
      if (this.onError) this.onError(err);
    });

    this.recorder.onFrameRecorded((res) => {
      if (!res.frameBuffer || res.frameBuffer.byteLength === 0) return;

      const pcm = new Int16Array(res.frameBuffer);
      this.detector.feed(pcm, this.sampleRate);

      const status = this.detector.getStatus();
      if (this.onUpdate) {
        this.onUpdate(status);
      }
    });
  }

  start() {
    if (this.isRecording) return;

    // 先检查并请求麦克风权限
    this._checkAndRequestPermission()
      .then(() => this._doStart())
      .catch((err) => {
        console.error('mic permission error', err);
        if (this.onError) this.onError(err);
      });
  }

  _checkAndRequestPermission() {
    return new Promise((resolve, reject) => {
      wx.getSetting({
        success: (res) => {
          const auth = res.authSetting['scope.record'];

          if (auth === true) {
            // 已授权
            resolve();
            return;
          }

          if (auth === false) {
            // 之前拒绝过，需要引导去设置页
            this._showOpenSettings(reject);
            return;
          }

          // 未请求过权限，发起授权请求
          wx.authorize({
            scope: 'scope.record',
            success: () => resolve(),
            fail: (err) => {
              // 用户点击拒绝
              if (err.errCode === 12001 || (err.errMsg && err.errMsg.includes('auth deny'))) {
                this._showOpenSettings(reject);
              } else {
                reject(err);
              }
            }
          });
        },
        fail: reject
      });
    });
  }

  _showOpenSettings(reject) {
    wx.showModal({
      title: '需要麦克风权限',
      content: '汪汪大作战需要麦克风来检测你的狗叫声，请在设置中打开麦克风权限。',
      confirmText: '去设置',
      cancelText: '取消',
      success: (res) => {
        if (res.confirm) {
          wx.openSetting({
            success: (settingRes) => {
              if (settingRes.authSetting['scope.record']) {
                this._doStart();
              } else {
                reject(new Error('用户未在设置中开启麦克风权限'));
              }
            },
            fail: reject
          });
        } else {
          reject(new Error('用户取消授权'));
        }
      },
      fail: reject
    });
  }

  _doStart() {
    try {
      // 微信小游戏 onFrameRecorded 在部分环境（尤其是开发者工具模拟器）下不会实时触发，
      // 在真机上通常正常。这里用 1KB 帧大小（约 64ms）尝试获得较频繁的回调。
      this.recorder.start({
        duration: 600000,
        sampleRate: 16000,
        numberOfChannels: 1,
        format: 'PCM',
        frameSize: 1
      });
      // recorder started
    } catch (err) {
      console.error('[AudioRecorder] recorder.start() error', err);
      if (this.onError) this.onError(err);
    }
  }

  stop() {
    if (!this.isRecording) return;
    this.recorder.stop();
  }

  reset() {
    this.detector.reset();
  }

  getStatus() {
    return this.detector.getStatus();
  }
}