#include "prand.h"
#include <stdint.h>
#include <stdio.h>
#include <time.h>

#define BUILD_SEED                                                             \
    ((uint64_t)(__TIME__[0]) * (uint64_t)(__TIME__[1]) *                       \
     (uint64_t)(__TIME__[3]) * (uint64_t)(__TIME__[4]) *                       \
     (uint64_t)(__TIME__[6]) * (uint64_t)(__TIME__[7]))

#define PRNG_SAVE_INTERVAL 50 // Save every 1000 calls to prand()

static uint64_t seed = BUILD_SEED;

uint64_t prand() {
    seed = seed * 6364136223846793005ULL + 1;
    return seed;
}

inline uint64_t prand_range(uint64_t min, uint64_t max) {
    return min + (prand() % (max - min + 1));
}

void sprand(uint64_t s) {
    if (s) {
        seed = s;
    } else {
        rand_reseed();
    }
}

void rand_reseed() { seed = BUILD_SEED; }

#define PRAND_MAIN
#ifdef PRAND_MAIN
int main() {
    // time(NULL) provides a somewhat unique seed at runtime
    sprand(time(NULL));


    uint64_t rn1 = prand();
    uint64_t rn2 = prand();

    printf("rn1 = %lu\n", rn1);
    printf("rn2 = %lu\n", rn2);
}
#endif