#include "monocypher.h"
#include "seed.h"
#include <assert.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define PRINT_HEX(arr, len) print_hex(#arr, (const uint8_t *)(arr), (len))

void print_hex(const char *name, const uint8_t *data, size_t len) {
    printf("%s (%zu bytes):\n", name, len);

    for (size_t i = 0; i < len; i++) {
        if (i % 16 == 0)
            printf("  %04zx: ", i);

        printf("%02X ", data[i]);

        if ((i + 1) % 16 == 0 || i + 1 == len)
            printf("\n");
    }
}

int main(void) {
    /* These can be used if not on bare metal */
    // uint8_t seed[32];
    // arc4random_buf(seed, 32);

    uint8_t seckey[64]; /* secret key          */
    uint8_t pubkey[32]; /* Matching public key */
    PRINT_HEX(seed, seed_len);

    /* The seed is wiped automatically here */
    crypto_eddsa_key_pair(seckey, pubkey, seed);

    PRINT_HEX(pubkey, 32);
    PRINT_HEX(seckey, 64);

    uint8_t message[4];

    /* Generate a random message */
    arc4random_buf(message, 4);
    PRINT_HEX(message, sizeof(message));

    uint8_t signature[64];

    /* Sign it and store the signature in sig[] */
    crypto_eddsa_sign(signature, seckey, (const uint8_t *)message, sizeof(message));
    PRINT_HEX(signature, 64);

    /* Assert valid */
    assert(!crypto_eddsa_check(signature, pubkey, (const uint8_t *)message, sizeof(message)));

    /* Tamper with payload to invalidate the signature */
    arc4random_buf(message, 4);
    PRINT_HEX(message, sizeof(message));

    /* Assert invalid */
    assert(crypto_eddsa_check(signature, pubkey, (const uint8_t *)message, sizeof(message)));

    /* Wipe the secret key if it is no longer needed */
    crypto_wipe(seckey, 32);

    printf("Program finished: Ok!\n");
}