#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>


using namespace std;

void mapitE(string,char[]);
void mapitD(string,char[]);
void encryptdecrypt(const string,const char[],int,string&);

int main()
{
    string encrypt_decrypt[] = {"encrypt","decrypt"}, buffer, key, newbuffer = "";
    char filename[80];
    char encryptmap[128];
    char decryptmap[1280];
    char repeat;
    int i;
    int maplength;
    int choice;
    ofstream out;
    ifstream in;


    do
    {
    cout << "Enter 1 to Encrypt the file or 2 to Decrypt the file: ";
    cin >> choice;

    while (choice<1||choice>2)
    {
        cout << "Invalid choice!!!\n";
        cout << "Enter 1 to Encrypt or 2 to Decrypt: ";
        cin >> choice;
    }

    cout << "Enter the name of your file to " << encrypt_decrypt[choice-1] << ": ";
    cin >> filename;
    in.open(filename);

    if (in.fail())
    {
        cout << "The Input file could not open!!!\nCheck that the Input file is valid!!!\n\n";
        cout << "Enter the name of your file to " << encrypt_decrypt[choice-1] << ": ";
        cin >> filename;
        in.open(filename);
    }

    cout << "Enter the name that you want your Output file to be: ";
    cin >> filename;
    out.open(filename);
    cout << "Enter your Encryption Key with a max of 128 characters, all LOWER case: ";
    cin >> key;

    if (key.length()>128)
    {
        cout << "Your Encryption Key is too long!!!\n";
        cout << "Enter your Encryption Key with a max of 128 lower case characters: ";
        cin >> key;
    }

    maplength=key.length();

    if(choice==1)
    {
        mapitE(key,encryptmap);
    }
    else
    {
        mapitD(key,decryptmap);
    }
    getline(in,buffer);

    while(in)
    {
    if(choice==1)
    {
        encryptdecrypt(buffer,encryptmap,maplength,newbuffer);
    }
    else
    {
        encryptdecrypt(buffer,decryptmap,maplength,newbuffer);
    }
    out << newbuffer;
    newbuffer.erase(0);
    getline(in,buffer);
    }

    out.close();
    in.close();
    in.clear();
    out.clear();
    newbuffer.erase(0);

    cout << "Would you like to run the program again (y/n)?";
    cin >> repeat;
    }while (repeat == 'Y' || repeat == 'y');

    return 0;
}

void encryptdecrypt(const string buffer,const char map[],int len,string& newbuffer)
{
    int i=0;
    char t;
    char code;
    for (i=0;i<buffer.length();i++)
    {
        t=buffer[i];
        (t += 251 - ((i * 14) & 255));
        cout << "Buffer length: " << buffer.length() << endl;
        cout << "newbuffer length: " << newbuffer.length() << endl;
        newbuffer.push_back(t);
    }
    newbuffer.push_back('\n');
}

void mapitE(string key,char map[])
{
    int i;

    for (i=0;i<key.length();i++)
    map[i]=key[i]-'a';
}

void mapitD(string key,char map[])
{
    int i;

    for (i=0;i<key.length();i++)
        cout << endl;
}