rental_statement.rb

class Movie
  CHILDRENS = 2
  REGULAR = 0
  NEW_RELEASE = 1

  attr_reader :title
  attr_accessor :price_code

  def initialize(title, price_code)
    @title = title
    @price_code = price_code
  end
end

class Rental
  attr_reader :movie, :days_rented

  def initialize(movie, days_rented)
    @movie = movie
    @days_rented = days_rented
  end
end

class Customer
  attr_reader :name, :rentals

  def initialize(name)
    @name = name
    @rentals = []
  end

  def add_rental(rental)
    @rentals << rental
  end

  def statement
    total_amount = 0
    frequent_renter_points = 0
    result = "Rental Record for #{name}\n"
    rentals.each do |rental|
      this_amount = 0
      # determine amounts for each line
      case rental.movie.price_code
      when Movie::REGULAR
        this_amount += 2;
        if rental.days_rented > 2
          this_amount += (rental.days_rented - 2) * 1.5
        end
      when Movie::NEW_RELEASE
        this_amount += rental.days_rented * 3
      when Movie::CHILDRENS
        this_amount += 1.5
        if (rental.days_rented > 3)
          this_amount += (rental.days_rented - 3) * 1.5
        end
      end

      # add frequent renter points
      frequent_renter_points += 1

      # add bonus for a two day new release rental
      if rental.movie.price_code == Movie::NEW_RELEASE && rental.days_rented > 1
        frequent_renter_points += 1
      end
      # show figures for this rental
      result << "\t#{rental.movie.title}\t#{this_amount}\n"
      total_amount += this_amount
    end
    # add footer lines
    result << "Amount owed is #{total_amount}\n"
    result << "You earned #{frequent_renter_points} frequent renter points"
    result
  end
end

movies = [["Jaws", Movie::REGULAR], ["Frozen", Movie::CHILDRENS], ["Spectre", Movie::NEW_RELEASE], ["Ghost Busters", Movie::REGULAR]].map do |title, price_code|
  Movie.new(title, price_code)
end
customer = Customer.new("George")

customer.add_rental(Rental.new(movies[0], 3))
customer.add_rental(Rental.new(movies[1], 2))
customer.add_rental(Rental.new(movies[2], 5))

puts customer.statement