🐾 Callback Patterns in JavaScript Classes

✅ Option A: onDone = callback (Single Callback)

class Animal {
  constructor(name) {
    this.name = name;
    // A single callback property (can be assigned later)
    this.onDone = null;
  }

  performAction() {
    console.log(`${this.name} is running...`);

    // If the callback exists, call it
    if (this.onDone) {
      this.onDone(`${this.name} finished the action.`);
    }
  }
}

// Create instance
const dog = new Animal("Milo");

// Assign a callback function to be called when action is done
dog.onDone = (message) => {
  console.log("Callback received:", message);
};

dog.performAction();

✅ Option B: onDone(callback) (Multiple Callbacks)

class Animal {
  constructor(name) {
    this.name = name;
    // A list of callbacks to notify when done
    this._onDoneCallbacks = [];
  }

  // Method for registering a callback
  onDone(callback) {
    this._onDoneCallbacks.push(callback);
  }

  performAction() {
    console.log(`${this.name} is running...`);

    // Call all registered callbacks
    for (const cb of this._onDoneCallbacks) {
      cb(`${this.name} finished the action.`);
    }
  }
}

// Create instance
const dog = new Animal("Luna");

// Register multiple callbacks
dog.onDone((message) => console.log("Logger 1:", message));
dog.onDone((message) => console.log("Logger 2:", message));

dog.performAction();

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