Timer class in js

timer.js

class Timer {
  constructor(duration, callback) {
    this.duration = duration;
    this.callback = callback;
    this.remainingTime = duration;
    this.timerId = null;
    this.paused = false;
  }

  async start() {
    try {
      console.log('Countdown started.');
      this.timerId = setInterval(() => {
        if (!this.paused) {
          this.remainingTime -= 1000;
          console.log(`${this.remainingTime / 1000}s remaining.`);
          if (this.remainingTime <= 0) {
            clearInterval(this.timerId);
            console.log('Countdown completed.');
            this.callback();
          }
        }
      }, 1000);
    } catch (error) {
      console.error('Error during countdown:', error);
    }
  }

  async pause() {
    console.log('Countdown paused.');
    this.paused = true;
  }

  async resume() {
    console.log('Countdown resumed.');
    this.paused = false;
  }

  async cancel() {
    clearInterval(this.timerId);
    console.log('Countdown canceled.');
  }
}

// Example usage:
const countdown = new Timer(5000, async () => {
  console.log('Simulated async process completed.');
});

countdown.start();

// Pause after 2 seconds
setTimeout(() => countdown.pause(), 2000);

// Resume after 1 second
setTimeout(() => countdown.resume(), 3000);

// Cancel after 4 seconds
setTimeout(() => countdown.cancel(), 4000);