#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <functional>
#include <thread>

using namespace std;

typedef vector<char>::iterator itr;
typedef vector<char>::const_iterator citr;

vector<char> unos(string filename, unsigned int& n){
    ios_base::openmode mode = ios_base::binary;
    ifstream file (filename, mode);
   if(file.is_open())
   {
        //unsigned int n = 0;
        // read data as a block:
        file.read ((char*)&n,sizeof(unsigned int));
        cout << "Broj je = " << n << endl;

        vector<char> unos(n);
        vector<char>::iterator it;

        for(it=unos.begin(); it!=unos.end();it++){
            file.read((char*)&(*it), sizeof(char));
        }

        for(it=unos.begin(); it!=unos.end();it++){
            cout << *it << " ";
        }

        /*
        for(unsigned int i = 0; i<broj; i++){
            file.read((char*)&unos[i],sizeof(unos[i]));
        }
        */
        /*
        for(unsigned int i = 0; i<broj; i++){
            cout << unos[i] << ";";
        }
        */
        file.close();
        return unos;
   }
}

char* unosKey(string filename, unsigned int& n){

    ios_base::openmode mode = ios_base::binary;
    ifstream file (filename, mode);
    if(!file.is_open()){
            cout << "Greska pri otvaranju datoteke" << endl;
            exit(1);
    }

    file.read ((char*)&n,sizeof(unsigned int));
    cout << "Broj je = " << n << endl;

    char* key = (char*)malloc(n*sizeof(char));
    if(key==NULL){
        cout << "Nedovoljno memorije" << endl;
        exit(2);
    }
    for(unsigned int i = 0; i<n; i++)
        file.read((char*)&key[i], sizeof(char));

    for(unsigned int i = 0; i<n; i++)
        cout << key[i] << " ";

    file.close();
    return key;

}

void xorr(itr pocetak_izlaz, itr kraj_izlaz, citr poc_ulaz, char* key,int i){
    for(; pocetak_izlaz!=kraj_izlaz; pocetak_izlaz++,i++,poc_ulaz++){
        *pocetak_izlaz = (*poc_ulaz)^key[i%256];
    }
}

int main()
{

   /*std::ifstream file ("in.dat", ios_base::binary);
   if(file.is_open())
   {
        unsigned int broj = 0;
        // read data as a block:
        file.read ((char*)&broj,sizeof(unsigned int));
        cout << "Broj je = " << broj << endl;

        vector<char> unos(broj);

        for(unsigned int i = 0; i<broj; i++){
            file.read((char*)&unos[i],sizeof(unos[i]));
        }

        for(unsigned int i = 0; i<broj; i++){
            cout << unos[i] << ";";
        }

        file.close();
   }*/



   unsigned int inputN = 0;
   vector<char> input = unos("in.dat", ref(inputN));
   cout << endl;

   unsigned int keyN = 0;
   /*
   vector<char> key = unos("key.dat", keyN);
   */
   char* key = unosKey("key.dat", ref(keyN));
   cout << endl;
   //vector<char> out = unos("out.dat");

   /*
    std::ifstream file1 ("key.dat", ios_base::binary);
   //file.open("in.dat");

   if(file1.is_open())
   {
        unsigned int broj = 0;
        // read data as a block:
        file1.read ((char*)&broj,sizeof(unsigned int));
        cout << "Broj je = " << broj << endl;

        vector<char> unos(broj);

        for(unsigned int i = 0; i<broj; i++){
            file1.read((char*)&unos[i],sizeof(unos[i]));
        }

        for(unsigned int i = 0; i<broj; i++){
            cout << unos[i] << ";";
        }

        file1.close();
   }
    */

    vector<char> rez(inputN);
    vector<char>::const_iterator itinput = input.begin();
    //vector<char>::const_iterator itkey = key.begin();
    vector<char>::iterator itrez = rez.begin();

    cout << endl << endl << endl << "\t\t\t\t\tRESENJE:" << endl;

    int broj_niti;
   cout << "Unesi broj niti: ";
   cin >> broj_niti;

    int i = 0;
    int bajtova_po_niti;

    bajtova_po_niti = inputN/broj_niti;  // broj bajtova koje obradjuje 1 nit
    thread nit[broj_niti];

    int j;

    for(j = 0; j<broj_niti-1; j++){
        nit[j] = thread(xorr, rez.begin()+j*bajtova_po_niti, rez.end()+j*bajtova_po_niti+bajtova_po_niti, input.begin()+j*bajtova_po_niti, key, i);
        i = (i + bajtova_po_niti)%256;
    }

    nit[broj_niti-1] = thread(xorr, rez.begin()+j*bajtova_po_niti, rez.end(), input.begin()+j*bajtova_po_niti, key, i);

    for(j = 0; j<broj_niti;j++)
        nit[j].join();


    /*
    thread t(xorr, rez.begin(), rez.end(), input.begin(), key, i);
    t.join();
    */

    /*
    int i;
    for(itinput = input.begin(),i=0; itrez!=rez.end(); itrez++,i++,itinput++){
        *itrez = (*itinput)^key[i%256];
    }


    for(itrez=rez.begin(); itrez!=rez.end(); itrez++){
        cout << *itrez << " ";
    }

    vector<char> rez1(inputN);
    vector<char>::iterator itrez1 = rez1.begin();
    cout << endl << endl << endl << "\t\t\t\t\tRESENJE:" << endl;
    xorr(rez1.begin(), rez1.end(), input.begin(), input.end(), key);
    for(itrez1=rez1.begin(); itrez1!=rez1.end(); itrez1++){
        cout << *itrez1 << " ";
    }

    for(int i = 0; i<5; i++){
        cout << rez[i];
    }
    */

    // UPIS IZLAZA U DATOTEKU:
    std::ofstream file ("ou1.dat", ios::binary | ios::in | ios::out | ios::trunc);
    if(file.is_open())
    {
        file.write((char*)&inputN, sizeof(unsigned int));
        for(vector<char>::const_iterator it=rez.begin(); it!=rez.end(); it++)
            file.write((char*)&(*it),sizeof(char));
    }
    file.close();
    cout << endl << endl << "inputN = " << inputN << " keyN = " << keyN << endl;

    delete[] key;
    return 0;
}