A javascritpt based class to catalog Media objects.

library-catalog.js

class Media {
  constructor(title) {
    this._title = title;
    this._isCheckedOut = false;
    this._ratings = [];
  }
  get title(){
    return this._title;
  }
  get isCheckedOut(){
    return this._isCheckedOut;
  }
  get ratings(){
    return this._ratings;
  }
  set isCheckedOut(checked){
    this._isCheckedOut = checked;
  }
  toggleCheckOutStatus(){
    this.isCheckedOut = this.isCheckedOut !== false ? false : true;
  }
  getAverageRating(){
    let rating = this.ratings.reduce((currentSum, rating) => currentSum + rating, 0);
    return rating / this.ratings.length;
  }
  addRating(rating){
    if(typeof rating == 'number' && rating >= 1 && rating <= 5){
      this._ratings.push(rating);
    } else {
      console.log('It\'s not a valid rating');
    }
    
  }
}
class Book extends Media {
  constructor(author, title, pages){
    super(title);
    this._author = author;
    this._pages = pages;
  }
  get author(){
    return this._author;
  }
  get pages(){
    return this._pages;
  }
}
class Movie extends Media {
  constructor(director, title, runTime){
    super(title);
    this._director = director;
    this._runTime = runTime;
  }
  get director(){
    return this._director;
  }
  get runTime(){
    return this._runTime;
  }
}

const historyOffEverything = new Book('Bill Bryson', 'A Short History of Nearly Everything', 544);
const speed = new Movie('Jan de Bont', 'Speed', 116);