P5: OO Inheritance.rb

class Vehicle
  def initialize(args)
    @color = args[:color]
    @wheels = args[:wheels]
  end
  
  def drive
    if crash
      @status = :crashed
    else
      @status = :driving
    end
  end
  
  def brake
    @status = :stopped
  end

  def crash
    return [true,false,false,false,false].sample
  end

  def needs_gas?
    return [true,true,false].sample
  end
end

class Car < Vehicle
  @@WHEELS = 4
  def initialize(args)
    super(args)
    @wheels = @@WHEELS
  end
end

class Bus < Vehicle
  attr_reader :passengers

  def initialize(args)
    super(args)
    @num_seats = args[:num_seats]
    @fare = args[:fare]
    @passengers=[]
  end

  def drive
    return self.brake if stop_requested?
    super
  end

  def admit_passenger(passenger,money)
    @passengers << passenger if money > @fare
  end

  def stop_requested?
    return [true,false].sample
  end

  def needs_gas?
    return [true,true,true,false].sample
  end
end
 
 
class Motorbike < Vehicle
  @@WHEELS = 2
  def initialize(args)
    super(args)
    @wheels = @@WHEELS   
  end

  def rev_engine
    return "people are impressed"
  end

  def drive
    super
    @speed = :fast
  end
   
  def needs_gas?
    return [true,false,false,false].sample
  end

  def weave_through_traffic
    @status = :driving_like_a_crazy_person
  end
end


p car = Car.new({color: "red"})
p bus = Bus.new({color: "yellow", wheels: 8, num_seats: 12, fare: 6})
p bike = Motorbike.new({color: "green"})

[car, bus, bike].each do |vehicle|
  p vehicle.drive == :driving || :crashed unless bike 
  if vehicle == bike
    p vehicle.drive == :fast
    vehicle.weave_through_traffic == :driving_like_a_crazy_person
    vehicle.rev_engine == "people_are_impressed"
  end
  if vehicle == bus
    vehicle.admit_passenger("anirudh", 4)
    p vehicle.passengers == []
    vehicle.admit_passenger("ani", 8)
    p vehicle.passengers == ["ani"]
  end 
  p vehicle.brake == :stopped
end