#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "sha256.h"

void print_long_hex_str(uint8_t* bytes, size_t len) {
    for(size_t i = 0; i < len; i  ) {
        if(i > 0 && (i % 4) == 0) {
            printf(" ");
        }
        printf("%x%x", bytes[i] >> 4, bytes[i] & 0xf);
    }
    printf("\n");
}

int main(int argc, char* argv[]) {
    uint8_t hash[32];

    printf("SHA-256 of \"\"\n");
    sha256("", 0, hash, 32);
    print_long_hex_str(hash, 32);

    printf("\nSHA-256 of \"abc\"\n");
    sha256("abc", 3, hash, 32);
    print_long_hex_str(hash, 32);

    printf("\nSHA-256 of \"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq\"\n");
    sha256("abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56, hash, 32);
    print_long_hex_str(hash, 32);

    // SHA-256 of a million a's.
    uint8_t* mill_a = malloc(1000000);
    if(mill_a == NULL) {
        printf("Sadly, malloc has failed.\n");
        return 0;
    }
    memset(mill_a, 'a', 1000000);
    sha256(mill_a, 1000000, hash, 32);
    printf("\nSHA-256 of \"a\" repeated one million times\n");
    print_long_hex_str(hash, 32);
    free(mill_a);

    sha256_hmac(
        "key", 3,
        "The quick brown fox jumps over the lazy dog", 43,
        hash, 32
    );
    printf("\nHMAC SHA-256 of \"The quick brown fox jumps over the lazy dog\"\n");
    printf("Using key: \"key\"\n");
    print_long_hex_str(hash, 32);

    // From https://tools.ietf.org/html/rfc4231
    uint8_t key[] = {
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa
    };
    sha256_hmac(
        key, sizeof(key),
        "Test Using Larger Than Block-Size Key - Hash Key First", 54,
        hash, 32
    );
    printf("\nHMAC SHA-256 of \"Test Using Larger Than Block-Size Key - Hash Key First\"\n");
    printf("Key is 131 bytes of 0xaa\n");
    print_long_hex_str(hash, 32);
    return 0;
}