Class: EnigmaEngine::Engine

Inherits:
Object
  • Object
show all
Includes:
DateKeyHelpers, FileHelpers, Offsets, Rotors
Defined in:
lib/enigma_engine/engine.rb

Direct Known Subclasses

Crack

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from DateKeyHelpers

#blue, #colorize, #date_valid?, #fields_empty?, #files_valid?, #green, #key_valid?, #red, #today, #yellow

Methods included from FileHelpers

#create_write_file, #open_file, #show_msg, #text_to_array

Methods included from Offsets

#a_offset, #b_offset, #c_offset, #d_offset, #get_date

Methods included from Rotors

#a_rotation, #b_rotation, #c_rotation, #d_rotation, #key, #put_key

Instance Attribute Details

#date ⇒ Object

Returns the value of attribute date.



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# File 'lib/enigma_engine/engine.rb', line 14

def date
  @date
end

#key=(value) ⇒ Object (writeonly)

Sets the attribute key

Parameters:

  • value —

    the value to set the attribute key to.



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# File 'lib/enigma_engine/engine.rb', line 13

def key=(value)
  @key = value
end

Instance Method Details

#characters ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 23

def characters
  ('a'..'z').to_a + ('0'..'9').to_a + [32.chr, 46.chr, 44.chr]
end

#decrypt(file, new_file, key, date) ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 69

def decrypt(file, new_file, key, date)
  @key = key
  @date = date
  message = text_to_array(open_file(file))
  decrypted_chars = []
  message.each do |row|
    row.each_with_index do |item, index|
      reversed = handle_rotation(index, item, method(:decrypt_char))
      decrypted_chars.push(reversed)
    end
  end
  create_write_file(decrypted_chars.join(''), new_file, key, date)
end

#decrypt_char(char, pos) ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 34

def decrypt_char(char, pos)
  char.downcase!
  pos *= -1
  char_map_hash = Hash[characters.zip(characters.rotate(pos))]
  res = char.chars.map { |c| char_map_hash.fetch(c) }
  res.join('')
end

#encrypt(file, new_file) ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 55

def encrypt(file, new_file)
  @key = rand_key
  @date = today
  message = text_to_array(open_file(file))
  encrypted_chars = []
  message.each do |row|
    row.each_with_index do |item, index|
      rotated = handle_rotation(index, item, method(:encrypt_char))
      encrypted_chars.push(rotated)
    end
  end
  create_write_file(encrypted_chars.join(''), new_file, @key, date, true)
end

#encrypt_char(char, pos) ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 27

def encrypt_char(char, pos)
  char.downcase!
  char_map_hash = Hash[characters.zip(characters.rotate(pos))]
  res = char.chars.map { |c| char_map_hash.fetch(c) }
  res.join('')
end

#handle_rotation(index, item, func) ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 42

def handle_rotation(index, item, func)
  case index
  when 0 then func.call(item, a_rotation + a_offset)
  when 1 then func.call(item, b_rotation + b_offset)
  when 2 then func.call(item, c_rotation + c_offset)
  when 3 then func.call(item, d_rotation + d_offset)
  end
end

#rand_key ⇒ Object 



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# File 'lib/enigma_engine/engine.rb', line 51

def rand_key
  rand(999_99).to_s.center(5, rand(9).to_s)
end