book.rb

require 'json'
class Book
  attr_accessor :title, :author, :rentals

  def initialize(title, author)
    @title = title
    @author = author
    @rentals = []
  end

  def add_rental(rental)
    @rentals << rental
    rental
  end

  def self.save_books_to_json(books)
    books_data = books.map(&:to_hash)
    File.write('books.json', JSON.pretty_generate(books_data))
  end

  def self.load_books_from_json
    books_data = JSON.parse(File.read('books.json'))
    books_data.map { |data| Book.new(data['title'], data['author']) }
  rescue StandardError
    []
  end

  def to_hash
    {
      'title' => @title,
      'author' => @author,
      'rentals' => @rentals.map { |rental| { 'date' => rental.date } }
    }
  end

  def self.find_by_title(books, title)
    books.find { |book| book.title == title }
  end
end