//*************************************//
//******** created by mamo139 *********//
//*** http://mamo139.altervista.org ***//
//*************************************//

#include <stdio.h>
#include <windows.h>

unsigned char* dammibit(unsigned char numero);
unsigned char dammichar(unsigned char *bits);
/*
    char *bits;
   bits = new char [8];
   bits = dammibit(154);
*/

int main (void){
   
   char nomefileb[20];
    printf("nome del file base:");
    scanf("%s",nomefileb);
    printf("%s!\n",nomefileb);
    //peso supportabile dal file base con steganografia 3-3-2bit
    FILE * pFile;
    long lSize;
    pFile = fopen ( nomefileb , "rb" );
    fseek (pFile , 0 , SEEK_END);
    lSize = ftell (pFile);
    fclose (pFile);
    printf("massimo peso sostenibile: %d kb!\n",(lSize/(3*1024)));
   
   char nomefiles[20];
    printf("nome del file da steganografare:");
    scanf("%s",nomefiles);
    printf("%s!\n",nomefiles);   
    //peso del file da steganografare
    FILE * pFile2;
    long lSize2;
    pFile2 = fopen ( nomefiles , "rb" );
    fseek (pFile2 , 0 , SEEK_END);
    lSize2 = ftell (pFile2);
    fclose (pFile2);
    printf(" peso file da steganografare: %d kb... operazione ",(lSize2/1024));
    if((lSize2/1024)<(lSize/(3*1024))) printf("FATTIBILE \n\n");
    else {printf("NON FATTIBILE \n\n");return 0; }
   
    //******************** inizio operazioni di steganografia ***************************//
    long lbuffer = 3; //byte letti alla volta nella base
    long lbuffer2 = lbuffer/3; //byte letti nel file
    printf("buffer impostato a %d bytes\n",lbuffer);

    unsigned char *buf, *buf2; //buffer di lettura
    buf = new unsigned char [(lbuffer+54)]; //grandezza del buffer della base
    buf2 = new unsigned char [(lbuffer2+54)]; //grandezza del buffer del file
    FILE *base, *file, *f_out;
    if ((file = fopen(nomefiles, "rb")) &&(base = fopen(nomefileb, "rb")) && (f_out = fopen("cript.bmp", "wb"))){
             
        printf("files aperti con successo!!\n"); 
           
        size_t b,c; //byte letti
        long x=0; //variabile per il ciclo
        b = fread( buf, 1, 54, base);
        fwrite( buf, 1, b, f_out);
       
        while( c = fread( buf2, 1, lbuffer2, file) ) {
               b = fread( buf, 1, lbuffer, base);
               
               /* ciclo di steganografia */
               x=x+lbuffer; // x = numero di byte letti dalla base


                     unsigned char *bits_f;
                    bits_f = new unsigned char [8];
                    bits_f = dammibit(buf2[0]);
                    
                     unsigned char *bits_b1;
                    bits_b1 = new unsigned char [8];
                    bits_b1 = dammibit(buf[0]);
                    unsigned char *bits_b2;
                    bits_b2 = new unsigned char [8];
                    bits_b2 = dammibit(buf[1]);
                    unsigned char *bits_b3;
                    bits_b3 = new unsigned char [8];
                    bits_b3 = dammibit(buf[2]);

                    bits_b1[5] = bits_f[0];
                    bits_b1[6] = bits_f[1];
                    bits_b1[7] = bits_f[2];
                    bits_b2[5] = bits_f[3];                    
                    bits_b2[6] = bits_f[4];
                    bits_b2[7] = bits_f[5];
                    bits_b3[6] = bits_f[6];
                    bits_b3[7] = bits_f[7];
                    
                    buf[0] = dammichar(bits_b1);
                    buf[1] = dammichar(bits_b2);
                    buf[2] = dammichar(bits_b3);
                    
               if(x%1048575==0)
               printf("%d Mb\n",(x/1048576));
               
               fwrite( buf, 1, b, f_out);

               
        }
       
        //lbuffer = 120000;
        printf("buffer reimpostato a %d bytes\n",lbuffer);
        while( b = fread( buf, 1, lbuffer, base) ){
               fwrite( buf, 1, b, f_out);
               if(x%1048575==0)
               printf("%d Mb\n",(x/1048576));               
        }
       
    }

       fclose(file);
       fclose(base);
       fclose(f_out);
      
    system("PAUSE");
    return 1;
}


unsigned char* dammibit(unsigned char numero){

   unsigned char *bits;
   bits = new unsigned char [8];

   if(numero<128) bits[0] = 0; // cifra 1
   else { bits[0] = 1; numero = numero - 128; }

   if(numero<64) bits[1] = 0; // cifra 2
   else { bits[1] = 1; numero = numero - 64; }

   if(numero<32) bits[2] = 0; // cifra 3
   else { bits[2] = 1; numero = numero - 32; }

   if(numero<16) bits[3] = 0; // cifra 4
   else { bits[3] = 1; numero = numero - 16; }

   if(numero<8) bits[4] = 0; // cifra 5
   else { bits[4] = 1; numero = numero - 8; }

   if(numero<4) bits[5] = 0; // cifra 6
   else { bits[5] = 1; numero = numero - 4; }

   if(numero<2) bits[6] = 0; // cifra 7
   else { bits[6] = 1; numero = numero - 2; }

   if(numero<1) bits[7] = 0; // cifra 8
   else { bits[7] = 1; numero = numero - 1; }
/*
   FILE *prova = fopen("output.txt","wb");
   fwrite( bits, 1, 8, prova);
   fclose(prova);
*/
    return bits;

}

unsigned char dammichar(unsigned char *bits){

   unsigned char numero;

    numero = bits[0]*128 + bits[1]*64 + bits[2]*32 + bits[3]*16 + bits[4]*8 + bits[5]*4 + bits[6]*2 + bits[7]*1;
   
    return numero;

}