/* Translated into C from Turbo Pascal, 23 Jan 2007 */

/********************************
   MAKE_ID System PIN Encoder
       Beta Version 2.1
     Arthur O'Dwyer, 6/2000

      10^10 possible PINs
  over 10^77 (possible) codes
********************************/

#include "ImageFmtc.h"
#include <stdlib.h>
#include <math.h>

#define SIZE (31) /* no more than 2^sqr(SIZE) keys */
#define KEYS (14) /* number of possibilities for each PIN digit */

unsigned char Image[SIZE*SIZE];

void GetNextStage(void)
{
    int i, j;
    int tmp[SIZE*SIZE];
    for (j=0; j < SIZE; ++j) {
        for (i=0; i < SIZE; ++i) {
            int x = (j > 0) && Image[(j-1)*SIZE+i];
            x ^= (j < SIZE-1) && Image[(j+1)*SIZE+i];
            x ^= (i > 0) && Image[j*SIZE+(i-1)];
            x ^= (i < SIZE-1) && Image[j*SIZE+(i+1)];
            tmp[j*SIZE+i] = x;
        }
    }

    for (j=0; j < SIZE; ++j) {
        for (i=0; i < SIZE; ++i) {
            if (tmp[j*SIZE+i])
              Image[j*SIZE+i] += (Image[j*SIZE+i] < 3);
            else Image[j*SIZE+i] = 0;
        }
    }
}


double MakeSeed(const char *idnum)
{
    int i;
    double m = 1.;
    double seed = 0.;
    for (i=0; i < 10; ++i) {
        m *= 2.5;
        if (*idnum) {
            seed += (*idnum % KEYS) * m;
            ++idnum;
        }
    }
    return seed;
}

void SaveImage(const char *fname)
{
#define N (1)
    int i, j;
    int a, b;
    unsigned char tmp[N*SIZE * N*SIZE];
    for (j=0; j < SIZE; ++j) {
        for (i=0; i < SIZE; ++i) {
            int t = Image[j*SIZE+i] + 1;
            if (t == 4) t = 3;
            t *= 60;
            for (a=0; a < N; ++a)
              for (b=0; b < N; ++b)
                tmp[(N*j+b)*(N*SIZE)+(N*i+a)] = t;
        }
    }
    WritePGM5(fname, tmp, N*SIZE, N*SIZE);
#undef N
}

static int Randomizer(int n) {
    return (unsigned int)(52.*log((double)n)) % 4;
}

int main(int argc, char **argv)
{
    char *id;
    double seed;
    int i, j;

    if (argc < 2) {
        puts("Usage: make_id password [output.pgm]");
        return 0;
    }
    id = argv[1];
    if (strlen(id) > 10) {
        puts("Password must be at most 10 characters");
        return 0;
    }

    seed = MakeSeed(id);
    for (i=0; i < SIZE; ++i)
      for (j=0; j < SIZE; ++j)
        Image[j*SIZE+i] = Randomizer(seed + (i+1)+(j+1)*16);

    for (i=0; i < SIZE; ++i) {
        char buf[100];
        sprintf(buf, "im%02d.pgm", i);
        SaveImage(buf);
        GetNextStage();
    }

    SaveImage("output.pgm");
    return 0;
}