#define _XOPEN_SOURCE 500
#define _GNU_SOURCE
#define _FILE_OFFSET_BITS 64
#define _LARGEFILE_SOURCE
#define _LARGEFILE64_SOURCE

#include <ftw.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <getopt.h>
#include <time.h>
#include <sys/time.h>

#include "store.h"

static unsigned long long	min_size = 0;
static unsigned short		verbose = 0;
static unsigned short		debug = 0;
static unsigned int		zero = 0;
static char			*out_file;

static struct option options[] =
{
	{"zero",	no_argument,		NULL,	'z'},
	{"min-size",	required_argument,	NULL,	'i'},
	{"out",		required_argument,	NULL,	'o'},
	{"verbose",	no_argument,		NULL,	'v'},
	{"debug",	no_argument,		NULL,	'd'},
	{NULL,		0,			NULL,	0}
};

static void usage(void)
{
	fprintf(stderr, "Usage: dupdump [options] <dir1> [<dir2>] ...\n"
		"	--zero		-z	Use \\0 to separate columns\n"
		"	--min-size	-i	Ignore files under this size (default 1)\n"
		"	--out		-o	Where to store results (default stdout)\n"
		"	--verbose	-v	Be more verbose (can be specified multiple times)\n"
		"	--debug		-d	Print debug information (can be specified multiple times)\n"
		);
}

/*
 * Callback for nftw function
 */
static int callback(const char *fpath, const struct stat *s, int tflag,
	struct FTW *ftwbuf)
{
	int err;

	if (verbose >= 2)
		fprintf(stderr, "%08x %s size=%jd base=%d level=%d dev=%lu ino=%lu\n",
			tflag, fpath,
			s->st_size,
			ftwbuf->base, ftwbuf->level,
			s->st_dev,
			s->st_ino);

	/* Allow only normal files and dirs */
	if ((!S_ISREG(s->st_mode)) && (!S_ISDIR(s->st_mode)))
		return 0;

	/* Add dir */
	if (tflag == FTW_D) {
		err = dir_add(fpath, s, ftwbuf->level);
		if (err) {
			fprintf(stderr, "ERROR: Probably out of memory!\n");
			return FTW_STOP;
		}

		return FTW_CONTINUE;
	}

	err = file_add(fpath, s, ftwbuf->level);
	if (err) {
		fprintf(stderr, "ERROR: Cannot add file!\n");
		return FTW_STOP;
	}

	return FTW_CONTINUE;
}

int main(int argc, char *argv[])
{
	int flags = 0;
	int err;
	int options_index = 0;
	int c;
	FILE *out;
	struct timeval start, end;

	while ((c = getopt_long(argc, argv, "zi:o:vdh", options, &options_index)) != -1) {
		switch (c) {
		case 'z': zero = 1; break;
		case 'i': min_size = strtoull(optarg, NULL, 10); break;
		case 'o': out_file = optarg; break;
		case 'v': verbose++; break;
		case 'd': debug++; break;
		default:
			usage();
			return 1;
		}
	}

	if (out_file == NULL) {
		out = stdout;
	} else {
		out = fopen(out_file, "w");
		if (out == NULL) {
			fprintf(stderr, "Cannot open results file (%s)!\n",
				strerror(errno));
			return 1;
		}
	}

	flags |= FTW_PHYS; /* Do not follow symlinks */
	flags |= FTW_ACTIONRETVAL; /* To skip hierarchies */

	if (optind >= argc) {
		usage();
		fprintf(stderr, "Error: no dirs to scan specified!\n");
		fclose(out);
		return 1;
	}

	set_debug(debug);
	set_out(out);

	if (verbose)
		fprintf(stderr, "Scanning for duplicates, min-size %llu\n",
			min_size);

	gettimeofday(&start, NULL);
	while (optind < argc) {
		if (verbose)
			fprintf(stderr, "Processing dir %s...\n", argv[optind]);

		err = nftw(argv[optind], callback, 100, flags);
		if (err == -1) {
			fprintf(stderr, "Error: cannot search dir [%s] [%d] (%s)\n",
				argv[optind], err, strerror(errno));
			return 1;
		}

		optind++;
	}

	if (debug > 2)
		dump_files();

	if (verbose)
		fprintf(stderr, "Finding duplicate files...\n");
	err = file_find_dups();
	if (err != 0) {
		fprintf(stderr, "Error comparing files!\n");
		return 1;
	}

	if (verbose)
		fprintf(stderr, "Finding duplicate dirs...\n");
	err = dir_find_dups();
	if (err != 0) {
		fprintf(stderr, "Error in finding dups procedure!\n");
		return 1;
	}

	if (debug > 2)
		dump_dirs();

	dump_duplicates(min_size, zero);

	gettimeofday(&end, NULL);

	if (verbose) {
		time_t diff;

		dump_stats();

		diff = end.tv_sec - start.tv_sec;
		fprintf(stderr, "[*] Time: %luh%lum%lus.\n",
			diff / 3600, (diff % 3600) / 60, diff % 60);
	}

	dev_ino_seen_clean();

	return 0;
}