#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <dirent.h>
#include <sys/stat.h>
#include "make_path.h"
#include "get_stat.h"
#include "parse_mode.h"

int (*get_stat)(const char *prog_name, const char *path, struct stat *stat_path);
unsigned int r_flag;
unsigned int s_flag;

int change(const char *file, const char *mode_arg) {
	struct stat old_file;
	if (get_stat("chmod", file, &old_file))
		return 1;

	mode_t mode = mu_parse_mode(mode_arg, old_file.st_mode);
	if (chmod(file, mode) != 0) {
		if (!s_flag)
			fprintf(stderr, "chmod: unable to chown %s: %s\n", file, strerror(errno));

		return 1;
	}

	return 0;
}

int chtree(const char *dst, const char *mode_arg) {
	int ret = change(dst, mode_arg);

	struct stat stat_path;
	if (get_stat("chmod", dst, &stat_path))
		return 1;

	if (!S_ISDIR(stat_path.st_mode) || !r_flag)
		return ret;

	DIR *dir = opendir(dst);
	if (dir == NULL) {
		if (!s_flag)
			fprintf(stderr, "chown: %s: Can`t open directory\n", dst);

		return 1;
	}

	struct dirent *ep;
	while ((ep = readdir(dir)) != NULL) {
		if (!strcmp(ep->d_name, ".") || !strcmp(ep->d_name, ".."))
			continue;

		char *full_path = mu_make_path("chmod", dst, ep->d_name);
		if (full_path == NULL)
			continue;

		if (chtree(full_path, mode_arg))
			ret = 1;

		free(full_path);
	}

	closedir(dir);
	return ret;
}

int main(int argc, char **argv) {
	get_stat = mu_get_lstat;

	/* Arg hacking */
	char *arg, **argp;
	argp = argv;
	while ((arg = *++argp)) {
		if (arg[0] != '-') {
			arg = NULL;
			break;
		}

		if (arg[1] && (!strchr("-x", arg[1]) || !strchr("-r", arg[1]) || !strchr("-w", arg[1]))) {
			arg[0] = 'a';
			break;
		}
	}

	int opt;
	while ((opt = getopt(argc, argv, "RfH") != -1)) {
		switch (opt) {
			case 'R':
				r_flag = 1;
				break;

			case 'f':
				s_flag = 1;
				break;

			case 'H':
				get_stat = mu_get_stat;
				break;

			default:
				printf("chmod [ugoa]{+|-}[rwxXst] / [0 - 777] [file1 file2...]\n\t[-H If a command line argument is a symbolic link]\n\t[-R Recursive] [-s Silent]\n");
				return 0;
		}
	}

	if (argv[optind] == NULL) {
		fprintf(stderr, "chmod: missing operand\n");
		return 0;
	}

	/* Fix arg */
	if (arg)
		arg[0] = '-';

	char *mode_arg = argv[optind];
	argv += optind;
	argc -= optind;

	int ret = 0;
	for (int i = 1; i < argc; i++)
		if (chtree(argv[i], mode_arg))
			ret = 1;

	return ret;
}