Class: EnigmaRuby::Rotor

Inherits:
Object
  • Object
show all
Defined in:
lib/enigma_ruby/rotor.rb

Instance Method Summary collapse

Constructor Details

#initialize(wiring, position = 0) ⇒ Rotor

Returns a new instance of Rotor.



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# File 'lib/enigma_ruby/rotor.rb', line 3

def initialize(wiring, position = 0)
  @wiring = wiring.chars
  @position = @notch = position
end

Instance Method Details

#advance ⇒ Object 



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# File 'lib/enigma_ruby/rotor.rb', line 18

def advance
  @position = (@position + 1) % wiring_size
end

#at_notch? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/enigma_ruby/rotor.rb', line 22

def at_notch?
  @position == @notch
end

#encode_backward(char) ⇒ Object 



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# File 'lib/enigma_ruby/rotor.rb', line 13

def encode_backward(char)
  index = @wiring.index(char)
  ((index - @position) % wiring_size + 'A'.ord).chr
end

#encode_forward(char) ⇒ Object 



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# File 'lib/enigma_ruby/rotor.rb', line 8

def encode_forward(char)
  index = (char.ord - 'A'.ord + @position) % wiring_size
  @wiring[index]
end