app.rb

require_relative 'app/repositories/meal_repository'
require_relative 'app/controllers/meals_controller'
require_relative 'router'

csv_file = 'data/meals.csv'
meal_repository = MealRepository.new(csv_file)
meals_controller = MealsController.new(meal_repository)


router = Router.new(meals_controller)
router.run

meal.rb

class Meal
  attr_reader :name, :price
  attr_accessor :id
  def initialize(attributes = {})
    @id = attributes[:id]
    @name = attributes[:name]
    @price = attributes[:price]
  end
end

meal_repository.rb

require 'csv'
require_relative '../models/meal'

class MealRepository
  def initialize(csv_file)
    @csv_file = csv_file
    @meals = []
    @next_id = 1
    # only run load csv if the file exists
    load_csv if File.exist?(@csv_file)
  end

  def all
    return @meals
  end

  def add(meal)
    # attr_accessor gives us meal.id & meal.id=
    meal.id = @next_id
    @next_id += 1
    @meals << meal
    save_csv
  end

  def find(id)
    @meals.find { |meal| meal.id == id }
  end

  private

  def load_csv
    csv_options = { headers: :first_row, header_converters: :symbol }

    CSV.foreach(@csv_file, csv_options) do |row|
      row[:id] = row[:id].to_i
      row[:price] = row[:price].to_i

      @meals << Meal.new(row)
    end
    # If there are no meals - id is 1
    @next_id = @meals.empty? ? 1 : @meals.last.id + 1
  end

  def save_csv
    CSV.open(@csv_file, 'wb') do |csv|
      csv << ['id', 'name', 'price']
      @meals.each do |meal|
        csv << [meal.id, meal.name, meal.price]
      end
    end
  end
end

meals_controller.rb

require_relative '../views/meals_view'

class MealsController
  def initialize(meal_repository)
    @meal_repository = meal_repository
    @meals_view = MealsView.new
  end

  def list
    # Gets the meals from the repo
    meals = @meal_repository.all
    # Ask the view to print the meals
    @meals_view.display_meals(meals)
  end

  def add
    # Ask the user for a name
    name = @meals_view.ask_user_for('name')
    # Ask the user for a price
    price = @meals_view.ask_user_for('price').to_i
    # Create a meal
    meal = Meal.new(name: name, price: price)
    # Add it to the repo
    @meal_repository.add(meal)
  end
end

meals_view.rb

class MealsView
  def display_meals(meals)
    meals.each_with_index do |meal, index|
      puts "#{index + 1} #{meal.name}, $#{meal.price}"
    end
  end

  def ask_user_for(attribute)
    puts "Please enter your #{attribute}"
    return gets.chomp
  end
end

router.rb

class Router
  def initialize(meals_controller)
    @meals_controller = meals_controller
    @running = true
  end

  def run
    while @running do
      list_options
      choice = gets.chomp.to_i
      dispatch(choice)
    end
  end

  private

  def stop
    @running = false
  end

  def list_options
    puts "What would you like to do?"
    puts "1. Keep going"
    puts "2. List meals"
    puts "3. Add meal"
    puts "9. Stop"
  end

  def dispatch(choice)
    case choice
    when 1 then puts 'hi'
    when 2 then @meals_controller.list
    when 3 then @meals_controller.add
    when 9 then stop
    else puts 'Wrong choice'
    end
  end
end