@minto-ai/huoshan-tts/src/tts-controller.ts

借助“火山引擎在线语音合成API”实现浏览器端“文本转语音

import type { InterfaceHandler } from './handler/core'
import type { BusinessParams, PrivateCustomEventName, PublicCustomEventName } from './types'
import { AudioActuator, ByteBuffer, DecodeData, TextSplit, TtsRequest } from './process'

import { SystemStatus } from './types'

import { createEventBus } from './utils/event-bus'

const $bus = createEventBus<PublicCustomEventName | PrivateCustomEventName>()

class TtsController {
  private textSplitInstance: TextSplit = new TextSplit()

  private audioActuatorInstance: AudioActuator = new AudioActuator()

  private ttsRequestInstance: TtsRequest = new TtsRequest()

  private byteBufferInstance: ByteBuffer = new ByteBuffer()

  private decodeDataInstance: DecodeData = new DecodeData()

  public systemStatus: SystemStatus = SystemStatus.OFFLINE

  constructor(businessParams: Partial<BusinessParams> = {}) {
    this.ttsRequestInstance.initProperty(businessParams)

    this.textSplitInstance.setExecuteController(this)
    this.ttsRequestInstance.setExecuteController(this)
    this.byteBufferInstance.setExecuteController(this)
    this.decodeDataInstance.setExecuteController(this)
    this.audioActuatorInstance.setExecuteController(this)

    this.textSplitInstance.linkHandler(this.ttsRequestInstance as unknown as InterfaceHandler)
    this.ttsRequestInstance.linkHandler(this.byteBufferInstance as unknown as InterfaceHandler)
    this.byteBufferInstance.linkHandler(this.decodeDataInstance as unknown as InterfaceHandler)
    this.decodeDataInstance.linkHandler(this.audioActuatorInstance as unknown as InterfaceHandler)

    this.bindEvent()
  }

  private bindEvent(): void {
    /**
     * 音频首次播放
     */
    $bus.on('_audioActuatorBeforeFirstExecute', () => {
      this.emit('audioFirstStart')
    })

    $bus.on('_appError', (error) => {
      this.finish()
      this.emit('appError', error)
    })

    $bus.on('_appFinish', () => {
      this.finish()
    })
  }

  /**
   *  进入待机状态，等待传入文本数据
   */
  public start(): TtsController {
    if (this.systemStatus === SystemStatus.EXECUTE) {
      return this
    }

    this.textSplitInstance.triggerHandlerActive()
    this.ttsRequestInstance.triggerHandlerActive()
    this.byteBufferInstance.triggerHandlerActive()
    this.decodeDataInstance.triggerHandlerActive()
    this.audioActuatorInstance.triggerHandlerActive()
    this.systemStatus = SystemStatus.EXECUTE

    return this
  }

  /**
   * 传入文本数据
   *
   * @param  text 待转换的文本
   */
  public send(text: string): TtsController {
    if (this.systemStatus !== SystemStatus.EXECUTE) {
      return this
    }

    this.textSplitInstance.handle(text)

    return this
  }

  /**
   * 应用停止处理传入的文本，但是并不会停止音频播放
   */
  public end(): TtsController {
    if (this.systemStatus !== SystemStatus.EXECUTE) {
      return this
    }

    this.textSplitInstance.handle(null)
    this.textSplitInstance.isHandleDataAcceptedComplete = true

    return this
  }

  /**
   * 停止所有处理器，并且重置状态，触发 appFinish 事件
   */
  public finish(): void {
    if (this.systemStatus === SystemStatus.OFFLINE) {
      return
    }

    this.textSplitInstance.triggerHandlerFinish()
    this.ttsRequestInstance.triggerHandlerFinish()
    this.byteBufferInstance.triggerHandlerFinish()
    this.decodeDataInstance.triggerHandlerFinish()
    this.audioActuatorInstance.triggerHandlerFinish()
    this.systemStatus = SystemStatus.OFFLINE

    this.emit('appFinish')
  }

  private emit<T>(eventName: PublicCustomEventName, data?: T): void {
    $bus.emit(eventName, data)
  }

  public on(eventName: PublicCustomEventName, callback: (data?: any) => void): TtsController {
    $bus.on(eventName, callback)
    return this
  }

  /**
   * 设置音量
   * @param {number} volume 音量 0-1
   */
  public setVolume(volume: number): void {
    this.audioActuatorInstance.setVolume(volume)
  }
}

export default TtsController