require 'rubygems'
require 'facets'


class BrainyiffDoggy
  
  def initialize
    #
    @memory = 30_000.of { 0 }
    # Position in memory.
    @pos = 0
    # nil is regular state.
    @state = nil
  end
  
  def perform(program_on_tape)
    #
    return if @state == :sleeping
    # Load the tape...
    @tape = program_on_tape
    # Go!
    @state = :yiffing
    until @state == :orgasm
      self.send @tape.instr
      @tape.advance
    end
    # Finish.
    @state = nil
  end
  
  def oh_my_god!
    tell "Oh my god!"
    if @memory[@pos] == 0
      @tape.advance until @tape.instr == :i_love_you!
    else
      @tape.remember_pos
    end
  end
  
  def i_love_you!
    tell "I love you!"
    @tape.restore_pos
    oh_my_god!
  end
  
  def yah!
    tell "Yah!"
    @pos += 1
    if @pos >= @memory.length then @pos = 0; end
  end
  
  def oh!
    tell "Oh!"
    @pos -= 1
    if @pos < 0 then @pos = @memory.length - 1; end
  end
  
  def yiff!
    tell "Yiff!"
    @memory[@pos] += 1
    if @memory[@pos] > 255 then @memory[@pos] = 0; end
  end
  
  def nngh!
    tell "Nngh!"
    @memory[@pos] -= 1
    if @memory[@pos] < 0 then @memory[@pos] = 0; end
  end
  
  def ah!
    tell "Ah!"
    putc @memory[@pos]
  end
  
  def more!
    tell "More!"
    @memory[@pos] = getc
  end
  
  def aaargh!
    tell "AAAAAAAARGH! ^o^"
    @state = :orgasm
  end
  
  def method_missing(method_id, *args, &block;)
    tell "What? #{method_id}?"
    super(method_id, *args, &block;)
  end
  
  private
  
  def tell(msg)
    STDERR.print(msg + " ")
  end
  
end


class TapeWithProgram
  
  def initialize(program)
    @program = program
    @pos = 0
    @stored_positions = []
  end
  
  def TapeWithProgram.compile(source_code)
    TapeWithProgram.new(
      source_code.
        downcase.
        split(/\!+/).
        map { |x| (x + "!").strip }.
        map { |x| if /aaa+rgh!/ === x then 'aaargh!' else x; end }.
        map { |x| x.gsub(/[^a-z!]/, '_').to_sym }
    )
  end
  
  # Symbol which can be sent to BrainyiffDoggy
  def current_instruction
    @program[@pos]
  end
  
  alias instr current_instruction
  
  def can_advance?
    @pos < (@program.length - 1)
  end
  
  def advance
    raise "Can not advance tape" unless can_advance?
    @pos += 1
  end
  
  def remember_pos
    @stored_positions.push @pos
  end
  
  def can_restore_pos?
    not @stored_positions.empty?
  end
  
  def restore_pos
    raise "Can not restore position in tape" unless can_restore_pos?
    @pos = @stored_positions.pop
  end
  
end


BrainyiffDoggy.new.perform(TapeWithProgram.compile((ARGV[0] or abort "Source file is not specified").file.read))