#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include "zpm.h"
#include "sha256.h"
#include "blake2.h"

static int hash_file(int fd, char *hash) {
	unsigned char buf[4096];
	ssize_t bytes;
	unsigned char tmp[32];
	int j;

#if 0
	struct sha256_state md;
	sha256_init(&md);
	do {
		bytes = read(fd, buf, sizeof buf);
		if (bytes == -1) {
			return 0;
		}
		sha256_process(&md, buf, bytes);
	} while (bytes);
	sha256_done(&md, tmp);
	for (j=0;j<32;j++) {
		sprintf(hash+j*2, "%02x", (unsigned)tmp[j]);
	}
	hash[64] = 0;

#else
	struct blake2b_state__ blake;
	blake2b_init(&blake, sizeof tmp);
	do {
		bytes = read(fd, buf, sizeof buf);
		if (bytes == -1) {
			return 0;
		}
		blake2b_update(&blake, buf, bytes);
	} while (bytes);
	blake2b_final(&blake, tmp, sizeof tmp);
	for (j=0;j<32;j++) {
		sprintf(hash+j*2, "%02x", (unsigned)tmp[j]);
	}
	hash[64] = 0;
#endif
	return 1;
}

int main(int ac, char **av){
	int rv;
	char hash[65];
	int input;
	char *filename;
	int i;

	for (i=1; i < ac; i++) {
		filename = av[i];
		if (strcmp(filename, "-") == 0) {
			input = 0;
		} else {
			input = open(filename, O_RDONLY);
			if (input == -1) {
				fprintf(stderr, "%s ", filename);
				perror("zpm-hash1");
				exit(EXIT_FAILURE);
			}
		}
		rv = hash_file(input, hash);
		close(input);
		if (rv == 0) {
			perror("zpm-hash2");
			exit(EXIT_FAILURE);
		}
		printf("%s\n", hash);
	}

	if (ac < 2) {
		filename = "-";
		rv = hash_file(0, hash);
		if (rv == 0) {
			perror("zpm-hash3");
			exit(EXIT_FAILURE);
		}
		printf("%s\n", hash);
	}

	return 0;
}