Javascript: Text-to-Speech (TTS) in Browser

tts.js

class TextToSpeech {
  constructor({ volume = 1, rate = 1, pitch = 1, lang = "en" } = {}) {
    if (typeof window === 'undefined' || !"speechSynthesis" in window) {
      throw new Error("Text to speech is not supported in your browser.");
    }

    this.engine = new SpeechSynthesisUtterance();
    this.setLanguage(lang)
      .setPitch(pitch)
      .setRate(rate)
      .setVolume(volume)
  }

  speak(text) {
    this.setText(text);
    window.speechSynthesis.speak(this.engine);
  }

  mute() {
    return this.setVolume(0);
  }

  unmute() {
    return this.setVolume(1);
  }

  setLanguage(lang) {
    this.engine.lang = lang;
    return this;
  }

  setPitch(pitch) {
    this.engine.pitch = pitch;
    return this;
  }

  setRate(rate) {
    this.engine.rate = rate;
    return this;
  }

  setVolume(volume) {
    this.engine.volume = volume;
    return this;
  }

  setText(text) {
    this.engine.text = text;
    return this;
  }
}

const tts = new TextToSpeech();
tts.speak(
  "Lemon lime minty coconut açai spiced pumpkin chili bananas dragon fruit red lentil curry shallots plums tabasco"
);