say.js/platform/linux.js

const SayPlatformBase = require('./base.js')

const BASE_SPEED = 100
const COMMAND = 'festival'

class SayPlatformLinux extends SayPlatformBase {
  constructor () {
    super()
    this.baseSpeed = BASE_SPEED
  }

  buildSpeakCommand ({ text, voice, speed }) {
    let args = []
    let pipedData = ''
    let options = {}

    args.push('--pipe')

    if (speed) {
      pipedData += `(Parameter.set 'Audio_Command "aplay -q -c 1 -t raw -f s16 -r $(($SR*${this.convertSpeed(speed)}/100)) $FILE") `
    }

    if (voice) {
      pipedData += `(${voice}) `
    }

    pipedData += `(SayText "${text}")`

    return { command: COMMAND, args, pipedData, options }
  }

  buildExportCommand ({ text, voice, speed, filename }) {
    throw new Error(`say.export(): does not support platform ${this.platform}`)
  }

  runStopCommand () {
    // TODO: Need to ensure the following is true for all users, not just me. Danger Zone!
    // On my machine, original childD.pid process is completely gone. Instead there is now a
    // childD.pid + 1 sh process. Kill it and nothing happens. There's also a childD.pid + 2
    // aplay process. Kill that and the audio actually stops.
    process.kill(this.child.pid + 2)
  }

  getVoices () {
    throw new Error(`say.export(): does not support platform ${this.platform}`)
  }
}

module.exports = SayPlatformLinux