紙一枚の積み重ね　：　ruby / オブジェクト指向まとめ

＃index.rb

require "./food"
require "./drink"

puts "日曜日限定100円割引セール実施中！"

food1 = Food.new(name: "ピザ", price: 800, calorie: 700)
food2 = Food.new(name: "すし", price: 1000, calorie: 600)
drink1 = Drink.new(name: "コーラ", price: 300, amount: 500)
drink2 = Drink.new(name: "お茶", price: 200, amount: 400)

menus = [food1, food2, drink1, drink2]

index = 0
menus.each do |menu|
 puts "#{index}. #{menu.info}"
 index += 1
end

puts "--------------"
puts "メニューの番号を選択してください"
order = gets.chomp.to_i

selected_menu = menus[order]
puts "選択されたメニュー: #{selected_menu.name}"

puts "個数を入力してください(3つ以上で100円割引)"
count = gets.chomp.to_i

puts "お会計は#{selected_menu.get_total_price(count)}円です"

#menu.rb

require "date"

class Menu
 attr_accessor :name
 attr_accessor :price

 def initialize(name:, price:)
   self.name = name
   self.price = price
 end
 
 def info
   return "#{self.name} #{self.price}円"
 end
 
 def get_total_price(count)
   total_price = self.price * count
   if count >= 3
     total_price -= 100
   end
   

   if count>=1 && Menu.is_discount_day?
      total_price -=100
   end
   return total_price
 end
 
 def Menu.is_discount_day?
   today = Date.today
   return today.sunday?
 end
end

#food.rb

require "./menu"

class Food < Menu
 attr_accessor :calorie
 
 def initialize(name:, price:, calorie:)
   super(name: name, price: price)
   self.calorie = calorie
 end
 
 def info
   return "#{self.name} #{self.price}円 (#{self.calorie}kcal)"
 end
 
 def calorie_info
   return "#{self.name}は#{self.calorie}kcalです"
 end
end

#drink.rb

require "./menu"

class Drink < Menu
 attr_accessor :amount
 
 def initialize(name:, price:, amount:)
   super(name: name, price: price)
   self.amount = amount
 end
 
 def info
   return "#{self.name} #{self.price}円 (#{self.amount}mL)"
 end
end