require 'prime'

class RSA
    def initialize(n, e, d)
        @n = n
        @e = e
        @d = d

    end

    def n
        #returns the value of 'n' passed in the initialize
        return n
    end

    def e
        #returns the value of 'e' passed in the initialize
        return e
    end

    def d
        #returns the value of 'd' passed in the initialize
        return d
    end

    def gcd (e, euler)

        if e > euler
            gcd = e
        else
            gcd = euler
        end

        while gcd != 1 do
            if(e%gcd == 0 && euler%gcd == 0)
                return gcd
            else
                gcd = gcd - 1
            end
        end
    end

    def new_key
    #generates a new 'n','e' and 'd' values following the RSA algorithm. Returns a new array of three elements where the first element is 'n', the second is 'e' and the third is 'd'. Each time it     is called a new key must be returned.
        q = Random.new
        q.rand(10...99)
        while Prime.prime(q) == true do
            q.rand(10...99)
        end

        p = Random.new
        p.rand(10...99)
        while Prime.prime(p) == true do
            p.rand(10...99)
        end
        n = p*q
        euler = (p-1).lcm(q-1)
        e.rand(2...euler)
        while gcd(e,euler) != 1 do
            e.rand(2..euler)
        end
        d = Random.new
        d.rand(1...1000)
        while d*e%euler!=1 do
            d.rand(1...1000)
        end
        array = Array.new(3)
        array.push(n)
        array.push(e)
        array.push(d)
        @n = n
        @e = e
        @d = d
        return array


    end

    def encrypt message
    #encrypts the message passed. The message is of type string. Encrypts each symbol of this string by using its ASCII number representation and returns the encrypted message.

    end

def decrypt message
#decrypts the message passed. The message is of type string. Decrypts each symbol of this string Encrypts each symbol of this string by using its ASCII number representationand returns the decrypted message.
end

end