gistfile1.rb

puts "Enter Password: "

password = gets

if password.chomp != "password"
  abort("WRONG PASSWORD")
end

class Encryptor

  def cipher(rotation)
    characters = (' '..'z').to_a
    rotated_characters = characters.rotate(rotation)
    Hash[characters.zip(rotated_characters)]
  end

  def encrypt_letter(letter,rotation)
    cipher_for_rotation = cipher(rotation)
    cipher_for_rotation[letter]
  end

  def encrypt(string,rotation)
    letters = string.split("")
    
    encrypted_letter = letters.collect do |letter|
      encrypted_letter = encrypt_letter(letter,rotation)
    end
    encrypted_letter.join
  end

  def decrypt_letter(letter,rotation)
    cipher_for_rotation = cipher(rotation)
    cipher_for_rotation[letter]
  end

  def decrypt(string,rotation)
    letters = string.split("")
    decrypted_letter = letters.collect do |letter|
      decrypted_letter = decrypt_letter(letter,-rotation)
    end
    decrypted_letter.join
  end

  def encrypt_file(filename, rotation)
    input = File.open(filename, "r")
    read_file = input.read
    encrypted_file = encrypt(read_file, rotation)
    encrypted_file_name = filename+".encrypted"
    out = File.open(encrypted_file_name, "w")
    out.write(encrypted_file)
    out.close
  end

  def decrypt_file(filename, rotation)
    input = File.open(filename, "r")
    read_file = input.read
    decrypted_file = decrypt(read_file, rotation)
    decrypted_file_name = filename.gsub("encrypted", "decrypted")
    out = File.open(decrypted_file_name, "w")
    out.write(decrypted_file)
    out.close
  end

  def supported_characters
    (' '..'z').to_a
  end

  def crack(message)
    supported_characters.count.times.collect do |attempt|
      decrypt(message,attempt)
    end
  end

  def e_chat(rotation)
    puts "Begin Real-Time Encryption Chat\n"
    begin
      puts "Input: "
      msg = gets
      e_msg = encrypt(msg,rotation)
      puts "Encrypted Message: #{e_msg}" 
    end until msg.chomp.eql? "Quit"
  end

  def d_chat(rotation)
    puts "Begin Real-Time Decryption Chat\n"
    begin
      puts "Input: "
      msg = gets
      d_msg = decrypt(msg,rotation)
      puts "Decrypted Message: #{d_msg}"
    end until msg.chomp.eql? "Quit"
  end

end