Encryption Library

crypto.rb

module SimpleCrypt
    
    class Map
        attr_accessor :letters
        
        def initialize
            @letters = ('a'..'z').to_a
            @letters << "_"
            @letters.shuffle!
        end
        
    end
    
    class Cipher
        
        def initialize(map)
            @letters = map.letters
        end
        
        def mapping(type, character)
            matches(@letters, type, character)
        end
        
        def matches(letters, type, character)
            letters_copy = letters.dup
            encrypt = Proc.new{|letter| "#{letter}#{character}#{letters_copy.shift}" }
            decrypt = Proc.new{|letter| "#{letters_copy.shift}#{character}#{letter}" }
            if type == "encrypt"
                encrypt_map = ('a'..'z').to_a.map{ |letter|  encrypt[letter] }
                encrypt_map << "_#{character}#{letters_copy.shift}"
            else
                encrypt_map = ('a'..'z').to_a.map{ |letter|  decrypt[letter] }.sort
                encrypt_map << "#{letters_copy.shift}#{character}_"
            end
        end
    end
    
    class Encrypter < Cipher
        
        def mapping
            super('encrypt', @character)
        end
        
        def initialize(map, character = "=>")
            super(map)
            @character = character
        end
        
    end
    
    class Decrypter < Cipher
        
        def mapping
            super('decrypt', @character)
        end
        
        def initialize(map, character = "=>")
            super(map)
            @character = character
        end
        
    end
    
end

map = SimpleCrypt::Map.new
encrypter = SimpleCrypt::Encrypter.new(map)
puts encrypter.mapping
puts ""
decrypter = SimpleCrypt::Decrypter.new(map)
puts decrypter.mapping

Example Output

a=>p
b=>k
c=>z
d=>w
e=>o
f=>q
g=>s
h=>a
i=>j
j=>c
k=>l
l=>u
m=>d
n=>x
o=>b
p=>m
q=>r
r=>e
s=>t
t=>g
u=>y
v=>_
w=>f
x=>v
y=>i
z=>n
_=>h

_=>v
a=>h
b=>o
c=>j
d=>m
e=>r
f=>w
g=>t
i=>y
j=>i
k=>b
l=>k
m=>p
n=>z
o=>e
p=>a
q=>f
r=>q
s=>g
t=>s
u=>l
v=>x
w=>d
x=>n
y=>u
z=>c
h=>_