factory_method.rb

# frozen_string_literal: true

# This pattern is often useful in situations where a class cannot anticipate the type of objects it
# will need to create, or in situations where a class wants to delegate the responsibility of
# creating objects to one of its expert subclasses.

# Base class that defines the interface of the object to be created
class Car
  def drive
    raise NotImplementedError, 'This is an abstract class check one if its subclasses'
  end
end

# Subclass that specifies a car model
class AmgGt53 < Car
  def drive
    puts 'Now we\'re talking... Driving it!'
  end
end

# Subclass that specifies a car model
class Gle < Car
  def drive
    puts 'But why?'
  end
end

# The actual car factory class
class MercedesBenzFactory
  def self.create_car(car_type)
    case car_type
    when :amg_gt_53
      AmgGt53.new
    when :gle
      Gle.new
    else
      puts "#{car_type.to_s.capitalize} isn't from Mercedes. " \
        "And if my grandmother had wheels, she would have been a bike"
    end
  end
end

# Criando um objeto de carro usando a fábrica
MercedesBenzFactory.create_car(:gle).drive

MercedesBenzFactory.create_car(:amg_gt_53).drive

MercedesBenzFactory.create_car(:testarossa)