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

int make_temp_dir(char *tmp) {
	if (!mkdtemp(tmp)) {
		if (errno == EINVAL)
			fprintf(stderr, "mktemp: template does not end in exactly 'XXXXX': %s\n", tmp);

		else
			fprintf(stderr, "mktemp: %s\n", strerror(errno));

		return 1;
	}

	return 0;
}

int get_suffix(const char *str) {
	size_t len = strlen(str);
	for (size_t i = len - 1; i > 0; i--)
		if (str[i] == 'X')
			return len - i - 1;

	return 0;
}

int make_temp_file(char *tmp) {
	if (!strstr(tmp, "XXXXXX")) {
		fprintf(stderr, "mktemp: too few X's in template: %s\n", tmp);
		return 1;
	}

	int fd = mkstemps(tmp, get_suffix(tmp));
	if (fd < 0) {
		fprintf(stderr, "mktemp: %s\n", strerror(errno));
		return 1;
	}

	close(fd);
	return 0;
}

int main(int argc, char **argv) {
	unsigned int d_flag = 0;
	char *path = NULL;

	int opt;
	while ((opt = getopt(argc, argv, "dp:")) != -1) {
		switch (opt) {
			case 'd':
				d_flag = 1;
				break;

			case 'p':
				path = optarg;
				break;

			default:
				printf("mktemp [file]\n\t[-d Dir] [-p Base dir]\n");
				return 0;
		}
	}

	argv += optind;
	argc -= optind;

	if (argc == 0) {
		fprintf(stderr, "mktemp: missing operand\n");
		return 1;
	}

	if (argc > 1) {
		fprintf(stderr, "mktemp: extra operands\n");
		return 1;
	}


	if (path == NULL) {
		path = getenv("TMPDIR");
		if (!path || path[0] == '\0')
			path = "/tmp";
	}

	if (chdir(path)) {
		fprintf(stderr, "mktemp: %s\n", strerror(errno));
		return 1;
	}

	if (d_flag) {
		if (make_temp_dir(argv[0]))
			return 1;
	}

	else {
		if (make_temp_file(argv[0]))
			return 1;
	}

	printf("%s/%s\n", path, argv[0]);
	return 0;
}