/* the Music Player Daemon (MPD)
 * (c)2003-2004 by Warren Dukes (shank@mercury.chem.pitt.edu)
 * This project's homepage is: http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "directory.h"

#include "ls.h"
#include "command.h"
#include "tables.h"
#include "utils.h"
#include "path.h"
#include "log.h"
#include "playlist.h"
#include "conf.h"
#include "stats.h"

#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>

#define DIRECTORY_DIR		"directory: "
#define DIRECTORY_MTIME		"mtime: "
#define DIRECTORY_BEGIN		"begin: "
#define DIRECTORY_END		"end: "
#define DIRECTORY_INFO_BEGIN	"info_begin"
#define DIRECTORY_INFO_END	"info_end"
#define DIRECTORY_MPD_VERSION	"mpd_version: "
#define DIRECTORY_FS_CHARSET	"fs_charset: "

#define DIRECTORY_SEARCH_ALBUM		"album"
#define DIRECTORY_SEARCH_ARTIST		"artist"
#define DIRECTORY_SEARCH_TITLE		"title"
#define DIRECTORY_SEARCH_FILENAME	"filename"

typedef List DirectoryList;

typedef struct _Directory {
	char * utf8name;
	DirectoryList * subDirectories;
	struct _Directory * parentDirectory;
	SongList * songs;
	time_t mtime; /* modification time */
} Directory;

Directory * mp3rootDirectory;

char directorydb[MAXPATHLEN+1];

DirectoryList * newDirectoryList();

int addToDirectory(Directory * directory, char * shortname, char * name);

void freeDirectoryList(DirectoryList * list);

void freeDirectory(Directory * directory);

int exploreDirectory(Directory * directory);

int updateDirectory(Directory * directory);

int addSubDirectoryToDirectory(Directory * directory, char * shortname, char * name);

Directory * newDirectory(Directory * parentDirectory, char * dirname, time_t mtime) {
	Directory * directory;

	directory = malloc(sizeof(Directory));

	if(dirname!=NULL) directory->utf8name = strdup(dirname);
	else directory->utf8name = NULL;
	directory->parentDirectory = parentDirectory;
	directory->subDirectories = newDirectoryList();
	directory->songs = newSongList();
	if(mtime<0) directory->mtime = isDir(dirname);
	else directory->mtime = mtime;

	return directory;
}

void freeDirectory(Directory * directory) {
	freeDirectoryList(directory->subDirectories);
	removeSongsFromTables(directory->songs);
	deleteSongsFromPlaylist(directory->songs);
	freeSongList(directory->songs);
	if(directory->utf8name) free(directory->utf8name);
	free(directory);
}

DirectoryList * newDirectoryList() {
	return makeList((ListFreeDataFunc *)freeDirectory);
}

void freeDirectoryList(DirectoryList * directoryList) {
	freeList(directoryList);
}

void removeSongFromDirectory(Directory * directory, char * shortname) {
	void * song;

	if(findInList(directory->songs,shortname,&song)) {
		removeASongFromTables((Song *)song);
		deleteASongFromPlaylist((Song *)song);
		deleteFromList(directory->songs,shortname);
	}
}

int updateInDirectory(Directory * directory, char * shortname, char * name) {
	time_t mtime;
	void * song;
	void * subDir;

	if((mtime = isMusic(name))) {
		if(0==findInList(directory->songs,shortname,&song)) {
			LOG("adding %s\n",name);
			addToDirectory(directory,shortname,name);
		}
		else if(mtime>((Song *)song)->mtime) {
			LOG("updating %s\n",name);
			updateSongInfo((Song *)song);
		}
	}
	else if((mtime = isDir(name))) {
		if(findInList(directory->subDirectories,shortname,(void **)&subDir)) {
			updateDirectory((Directory *)subDir);
		}
		else addSubDirectoryToDirectory(directory,shortname,name);
	}

	return 0;
}

int removeDeletedFromDirectory(Directory * directory) {
	DIR * dir;
	char cwd[2];
	struct dirent * ent;
	char * dirname = directory->utf8name;
	List * entList = makeList(free);
	void * name;
	char * s;
	char * utf8;
	ListNode * node;
	ListNode * tmpNode;

	cwd[0] = '.';
	cwd[1] = '\0';
	if(dirname==NULL) dirname=cwd;

	if((dir = opendir(rmp2amp(utf8ToFsCharset(dirname))))==NULL) return -1;

	while((ent = readdir(dir))) {
		if(ent->d_name[0]=='.') continue; /* hide hidden stuff */

		utf8 = strdup(fsCharsetToUtf8(ent->d_name));

		if(directory->utf8name) {
			s = malloc(strlen(directory->utf8name)+strlen(utf8)+2);
			sprintf(s,"%s/%s",directory->utf8name,utf8);
		}
		else s= strdup(utf8);
		insertInList(entList,fsCharsetToUtf8(ent->d_name),s);
		free(utf8);
	}

	closedir(dir);

	node = directory->subDirectories->firstNode;
	while(node) {
		tmpNode = node->nextNode;
		if(findInList(entList,node->key,&name)) {
			if(!isDir((char *)name)) {
				deleteFromList(directory->subDirectories,node->key);
			}
		}
		else {
			deleteFromList(directory->subDirectories,node->key);
		}
		node = tmpNode;
	}

	node = directory->songs->firstNode;
	while(node) {
		tmpNode = node->nextNode;
		if(findInList(entList,node->key,(void **)&name)) {
			if(!isMusic(name)) {
				removeSongFromDirectory(directory,node->key);
			}
		}
		else {
			removeSongFromDirectory(directory,node->key);
		}
		node = tmpNode;
	}

	freeList(entList);

	return 0;
}

int updateDirectory(Directory * directory) {
	DIR * dir;
	char cwd[2];
	struct dirent * ent;
	char * s;
	char * utf8;
	char * dirname = directory->utf8name;

	cwd[0] = '.';
	cwd[1] = '\0';
	if(dirname==NULL) dirname=cwd;

	removeDeletedFromDirectory(directory);

	if((dir = opendir(rmp2amp(utf8ToFsCharset(dirname))))==NULL) return -1;

	while((ent = readdir(dir))) {
		if(ent->d_name[0]=='.') continue; /* hide hidden stuff */

		utf8 = strdup(fsCharsetToUtf8(ent->d_name));

		if(directory->utf8name) {
			s = malloc(strlen(directory->utf8name)+strlen(utf8)+2);
			sprintf(s,"%s/%s",directory->utf8name,utf8);
		}
		else s = strdup(utf8);
		updateInDirectory(directory,utf8,s);
		free(utf8);
		free(s);
	}
	
	closedir(dir);

	if(directory->utf8name) directory->mtime = isDir(directory->utf8name);

	return 0;
}

int exploreDirectory(Directory * directory) {
	DIR * dir;
	char cwd[2];
	struct dirent * ent;
	char * s;
	char * utf8;
	char * dirname = directory->utf8name;

	cwd[0] = '.';
	cwd[1] = '\0';
	if(dirname==NULL) dirname=cwd;

	DEBUG("explore: attempting to opendir: %s\n",dirname);
	if((dir = opendir(rmp2amp(utf8ToFsCharset(dirname))))==NULL) return -1;

	LOG("explore: %s\n",dirname);
	while((ent = readdir(dir))) {
		if(ent->d_name[0]=='.') continue; /* hide hidden stuff */

		utf8 = strdup(fsCharsetToUtf8(ent->d_name));

		DEBUG("explore: found: %s (%s)\n",ent->d_name,utf8);

		if(directory->utf8name) {
			s = malloc(strlen(directory->utf8name)+strlen(utf8)+2);
			sprintf(s,"%s/%s",directory->utf8name,utf8);
		}
		else s = strdup(utf8);
		addToDirectory(directory,utf8,s);
		free(utf8);
		free(s);
	}
	
	closedir(dir);

	return 0;
}

int addSubDirectoryToDirectory(Directory * directory, char * shortname, 
	char * name) 
{
	Directory * subDirectory = newDirectory(directory,name,-1);
	
	insertInList(directory->subDirectories,shortname,subDirectory);
	exploreDirectory(subDirectory);

	return 0;
}

int addToDirectory(Directory * directory, char * shortname, char * name) {
	if(isDir(name)) {
		return addSubDirectoryToDirectory(directory,shortname,name);
	}
	else if(isMusic(name)) {
		Song * song;
		song = addSongToList(directory->songs,shortname,name);
		if(!song) return -1;
		addSongToTables(song);
		return 0;
	}

	DEBUG("addToDirectory: %s is not a directory or music\n",name);

	return -1;
}

void closeMp3Directory() {
	freeDirectory(mp3rootDirectory);
}

Directory * findSubDirectory(Directory * directory,char * name) {
	void * subDirectory;
	char * dup = strdup(name);
	char * key;

	key = strtok(dup,"/");
	if(!key) {
		free(dup);
		return NULL;
	}
	
	if(findInList(directory->subDirectories,key,&subDirectory)) {
		free(dup);
		return (Directory *)subDirectory;
	}

	free(dup);
	return NULL;
}

Directory * getSubDirectory(Directory * directory,char * name) {
	Directory * subDirectory;
	int len;

	if(name==NULL || name[0]=='\0' || strcmp(name,"/")==0) {
		return directory;
	}

	if((subDirectory = findSubDirectory(directory,name))==NULL) return NULL;

	len = 0;
	while(name[len]!='/' && name[len]!='\0') len++;
	while(name[len]=='/') len++;

	return getSubDirectory(subDirectory,&(name[len]));
}

Directory * getDirectory(char * name) {
	return getSubDirectory(mp3rootDirectory,name);
}

int printDirectoryList(FILE * fp, DirectoryList * directoryList) {
	ListNode * node = directoryList->firstNode;
	Directory * directory;

	while(node!=NULL) {
		directory = (Directory *)node->data;
		myfprintf(fp,"%s%s\n",DIRECTORY_DIR,directory->utf8name);
		node = node->nextNode;
	}

	return 0;
}

int printDirectoryInfo(FILE * fp, char * name) {
	Directory * directory;
	
	if((directory = getDirectory(name))==NULL) {
		myfprintf(fp,"%s: directory not found\n",COMMAND_RESPOND_ERROR);
		return -1;
	}

	printDirectoryList(fp,directory->subDirectories);
	printSongInfoFromList(fp,directory->songs);

	return 0;
}

void writeDirectoryInfo(FILE * fp, Directory * directory) {
	ListNode * node = (directory->subDirectories)->firstNode;
	Directory * subDirectory;

	if(directory->utf8name) {
		myfprintf(fp,"%s%s\n",DIRECTORY_BEGIN,directory->utf8name);
	}
			
	while(node!=NULL) {
		subDirectory = (Directory *)node->data;
		myfprintf(fp,"%s%s\n",DIRECTORY_DIR,node->key);
		myfprintf(fp,"%s%li\n",DIRECTORY_MTIME,(long)subDirectory->mtime);
		writeDirectoryInfo(fp,subDirectory);
		node = node->nextNode;
	}

	writeSongInfoFromList(fp,directory->songs);

	if(directory->utf8name) {
		myfprintf(fp,"%s%s\n",DIRECTORY_END,directory->utf8name);
	}
}

void readDirectoryInfo(FILE * fp,Directory * directory) {
	char buffer[MAXPATHLEN*2];
	int bufferSize = MAXPATHLEN*2;
	char * key;
	Directory * subDirectory;
	char * name;
	time_t mtime;

	while(myFgets(buffer,bufferSize,fp) && 0!=strncmp(DIRECTORY_END,buffer,strlen(DIRECTORY_END))) {
		if(0==strncmp(DIRECTORY_DIR,buffer,strlen(DIRECTORY_DIR))) {
			key = strdup(&(buffer[strlen(DIRECTORY_DIR)]));
			if(myFgets(buffer,bufferSize,fp)<0) {
				ERROR("Error reading db\n");
				exit(-1);
			}
			if(strncmp(DIRECTORY_MTIME,buffer,strlen(DIRECTORY_MTIME))) {
				ERROR("Error reading db\n");
				ERROR("%s\n",buffer);
				exit(-1);
			}
			mtime = atoi(&(buffer[strlen(DIRECTORY_BEGIN)]));
			if(myFgets(buffer,bufferSize,fp)<0) {
				ERROR("Error reading db\n");
				exit(-1);
			}
			if(strncmp(DIRECTORY_BEGIN,buffer,strlen(DIRECTORY_BEGIN))) {
				ERROR("Error reading db\n");
				exit(-1);
			}
			name = strdup(&(buffer[strlen(DIRECTORY_BEGIN)]));
			subDirectory = newDirectory(directory,name,mtime);
			insertInList(directory->subDirectories,key,(void *)subDirectory);
			free(key);
			free(name);
			readDirectoryInfo(fp,subDirectory);
		}
		else if(0==strncmp(SONG_BEGIN,buffer,strlen(SONG_BEGIN))) {
			readSongInfoIntoList(fp,directory->songs);
		}
		else {
			ERROR("Unknown line in db: %s\n",buffer);
			exit(-1);
		}
	}
}

void sortDirectory(Directory * directory) {
	ListNode * node = directory->subDirectories->firstNode;
	Directory * subDir;
	
	sortList(directory->subDirectories);
	sortList(directory->songs);

	while(node!=NULL) {
		subDir = (Directory *)node->data;
		sortDirectory(subDir);
		node = node->nextNode;
	}
}

int writeDirectoryDB() {
	FILE * fp;

	sortDirectory(mp3rootDirectory);
	stats.numberOfSongs = countSongsIn(stderr,NULL);

	while(!(fp=fopen(directorydb,"w")) && errno==EINTR);
	if(!fp) return -1;

	myfprintf(fp,"%s\n",DIRECTORY_INFO_BEGIN);
	myfprintf(fp,"%s%s\n",DIRECTORY_MPD_VERSION,VERSION);
	myfprintf(fp,"%s%s\n",DIRECTORY_FS_CHARSET,getFsCharset());
	myfprintf(fp,"%s\n",DIRECTORY_INFO_END);

	writeDirectoryInfo(fp,mp3rootDirectory);
	while(fclose(fp) && errno==EINTR);

	return 0;
}

int readDirectoryDB() {
	FILE * fp;

	mp3rootDirectory = newDirectory(NULL,NULL,0);
	while(!(fp=fopen(directorydb,"r")) && errno==EINTR);
	if(!fp) return -1;

	/* get initial info */
	{
		char buffer[100];
		int bufferSize = 100;
		int foundFsCharset = 0;
		int foundVersion = 0;

		if(myFgets(buffer,bufferSize,fp)<0) {
			ERROR("Error reading db\n");
			exit(-1);
		}
		if(0==strcmp(DIRECTORY_INFO_BEGIN,buffer)) {
			while(myFgets(buffer,bufferSize,fp) && 
					0!=strcmp(DIRECTORY_INFO_END,buffer)) 
			{
				if(0==strncmp(DIRECTORY_MPD_VERSION,buffer,
						strlen(DIRECTORY_MPD_VERSION)))
				{
					if(foundVersion) {
						ERROR("already found "
							"version in db\n");
						exit(-1);
					}
					foundVersion = 1;
				}
				else if(0==strncmp(DIRECTORY_FS_CHARSET,buffer,
						strlen(DIRECTORY_FS_CHARSET)))
				{
					char * fsCharset; 

					if(foundFsCharset) {
						ERROR("already found "
							"fs charset in db\n");
						exit(-1);
					}

					foundFsCharset = 1;

					fsCharset = &(buffer[strlen(
							DIRECTORY_FS_CHARSET)]);
					if(getConf()[CONF_FS_CHARSET] && 
							strcmp(fsCharset,
							getFsCharset())) 
					{
						ERROR("Using \"%s\" for the "
							"filesystem charset "
							"instead of \"%s\"\n",
							fsCharset,
							getFsCharset());
						ERROR("maybe you need to "
							"recreate the db?\n");
						setFsCharset(fsCharset);
					}
				}
				else {
					ERROR("unknown line in db info: %s\n",
						buffer);
				}
			}
		}
		else {
			ERROR("db info not found in db file\n");
			ERROR("you should recreate the db using --create-db\n");
			fseek(fp,0,SEEK_SET);
		}
	}

	readDirectoryInfo(fp,mp3rootDirectory);
	while(fclose(fp) && errno==EINTR);

	stats.numberOfSongs = countSongsIn(stderr,NULL);

	return 0;
}

int updateMp3Directory(FILE * fp) {
	if(updateDirectory(mp3rootDirectory)<0) {
		ERROR("problems updating music db\n");
		myfprintf(fp,"%s problems updating music db\n",COMMAND_RESPOND_ERROR);
		return -1;
	}

	if(writeDirectoryDB()<0) {
		ERROR("problems writing music db file, \"%s\"\n",directorydb);
		myfprintf(fp,"%s problems writing music db\n",COMMAND_RESPOND_ERROR);
		return -1;
	}
	
	return 0;
}

int traverseAllInSubDirectory(FILE * fp, Directory * directory,
                                int (*forEachSong)(FILE *, Song *, void *),
                                int (*forEachDir)(FILE *, Directory *, void *),
				void * data)
{
        ListNode * node = directory->songs->firstNode;
        Song * song;
        Directory * dir;
        int errFlag = 0;

        if(forEachDir) {
                errFlag = forEachDir(fp,directory,data);
                if(errFlag) return errFlag;
        }

        if(forEachSong) {
                while(node!=NULL && !errFlag) {
                        song = (Song *)node->data;
                        errFlag = forEachSong(fp,song,data);
                        node = node->nextNode;
                }
                if(errFlag) return errFlag;
        }

        node = directory->subDirectories->firstNode;

        while(node!=NULL && !errFlag) {
                dir = (Directory *)node->data;
                errFlag = traverseAllInSubDirectory(fp,dir,forEachSong,
                                                        forEachDir,data);
                node = node->nextNode;
        }

        return errFlag;
}

int traverseAllIn(FILE * fp, char * name, 
			int (*forEachSong)(FILE *, Song *, void *),
			int (*forEachDir)(FILE *, Directory *, void *),
			void * data) {
	Directory * directory;

	if((directory = getDirectory(name))==NULL) {
		Song * song;
		if((song = getSong(name)) && forEachSong) {
			return forEachSong(fp, song, data);
		}
		myfprintf(fp,"%s: directory or file not found\n",COMMAND_RESPOND_ERROR);
		return -1;
	}

	return traverseAllInSubDirectory(fp,directory,forEachSong,forEachDir,
			data);
}

int countSongsInDirectory(FILE * fp, Directory * directory, void * data) {
	int * count = (int *)data;

	*count+=directory->songs->numberOfNodes;
	
        return 0;
}

int printDirectoryInDirectory(FILE * fp, Directory * directory, void * data) {
        if(directory->utf8name) {
		myfprintf(fp,"directory: %s\n",directory->utf8name);
	}
        return 0;
}

int printSongInDirectory(FILE * fp, Song * song, void * data) {
        myfprintf(fp,"file: %s\n",song->utf8file);
        return 0;
}

int searchForAlbumInDirectory(FILE * fp, Song * song, void * string) {
	if(song->tag && song->tag->album) {
		char * dup = strDupToUpper(song->tag->album);
		if(strstr(dup,(char *)string)) printSongInfo(fp,song);
		free(dup);
	}
	return 0;
}

int searchForArtistInDirectory(FILE * fp, Song * song, void * string) {
	if(song->tag && song->tag->artist) {
		char * dup = strDupToUpper(song->tag->artist);
		if(strstr(dup,(char *)string)) printSongInfo(fp,song);
		free(dup);
	}
	return 0;
}

int searchForTitleInDirectory(FILE * fp, Song * song, void * string) {
	if(song->tag && song->tag->title) {
		char * dup = strDupToUpper(song->tag->title);
		if(strstr(dup,(char *)string)) printSongInfo(fp,song);
		free(dup);
	}
	return 0;
}

int searchForFilenameInDirectory(FILE * fp, Song * song, void * string) {
	char * dup = strDupToUpper(song->utf8file);
	if(strstr(dup,(char *)string)) printSongInfo(fp,song);
	free(dup);
	return 0;
}

int searchForSongsIn(FILE * fp, char * name, char * item, char * string) {
	char * dup = strDupToUpper(string);
	int ret = -1;

	if(strcmp(item,DIRECTORY_SEARCH_ALBUM)==0) {
		ret = traverseAllIn(fp,name,searchForAlbumInDirectory,NULL,
			(void *)dup);
	}
	else if(strcmp(item,DIRECTORY_SEARCH_ARTIST)==0) {
		ret = traverseAllIn(fp,name,searchForArtistInDirectory,NULL,
			(void *)dup);
	}
	else if(strcmp(item,DIRECTORY_SEARCH_TITLE)==0) {
		ret = traverseAllIn(fp,name,searchForTitleInDirectory,NULL,
			(void *)dup);
	}
	else if(strcmp(item,DIRECTORY_SEARCH_FILENAME)==0) {
		ret = traverseAllIn(fp,name,searchForFilenameInDirectory,NULL,
			(void *)dup);
	}
	else myfprintf(fp,"%s unknown table\n",COMMAND_RESPOND_ERROR);

	free(dup);

	return ret;
}

int findAlbumInDirectory(FILE * fp, Song * song, void * string) {
	if(song->tag && song->tag->album && 
			strcmp((char *)string,song->tag->album)==0) 
	{
		printSongInfo(fp,song);
	}

	return 0;
}

int findArtistInDirectory(FILE * fp, Song * song, void * string) {
	if(song->tag && song->tag->artist && 
			strcmp((char *)string,song->tag->artist)==0) 
	{
		printSongInfo(fp,song);
	}

	return 0;
}

int findSongsIn(FILE * fp, char * name, char * item, char * string) {
	if(strcmp(item,DIRECTORY_SEARCH_ALBUM)==0) {
		return traverseAllIn(fp,name,findAlbumInDirectory,NULL,
			(void *)string);
	}
	else if(strcmp(item,DIRECTORY_SEARCH_ARTIST)==0) {
		return traverseAllIn(fp,name,findArtistInDirectory,NULL,
			(void *)string);
	}

	myfprintf(fp,"%s unknown table\n",COMMAND_RESPOND_ERROR);
	return -1;
}

int printAllIn(FILE * fp, char * name) {
	return traverseAllIn(fp,name,printSongInDirectory,
				printDirectoryInDirectory,NULL);
}

int directoryAddSongToPlaylist(FILE * fp, Song * song, void * data) {
	return addSongToPlaylist(fp,song);
}

int addAllIn(FILE * fp, char * name) {
	return traverseAllIn(fp,name,directoryAddSongToPlaylist,NULL,NULL);
}

int directoryPrintSongInfo(FILE * fp, Song * song, void * data) {
	return printSongInfo(fp,song);
}

int printInfoForAllIn(FILE * fp, char * name) {
        return traverseAllIn(fp,name,directoryPrintSongInfo,NULL,NULL);
}

int countSongsIn(FILE * fp, char * name) {
	int count = 0;
	void * ptr = (void *)&count;
	
        traverseAllIn(fp,name,NULL,countSongsInDirectory,ptr);

	return count;
}

void initMp3Directory() {
	mp3rootDirectory = newDirectory(NULL,NULL,0);
	exploreDirectory(mp3rootDirectory);
}

Song * getSong(char * file) {
	void * song;
	Directory * directory;
	char * dir = NULL;
	char * dup = strdup(file);
	char * shortname = dup;
	char * c = strtok(dup,"/");

	DEBUG("get song: %s\n",file);

	while(c) {
		shortname = c;
		c = strtok(NULL,"/");
	}

	if(shortname!=dup) {
		for(c = dup; c < shortname-1; c++) {
			if(*c=='\0') *c = '/';
		}
		dir = dup;
	}

	if(!(directory = getSubDirectory(mp3rootDirectory,dir))) {
		free(dup);
		return NULL;
	}

	if(!findInList(directory->songs,shortname,&song)) {
		free(dup);
		return NULL;
	}

	free(dup);
	return (Song *)song;
}

time_t getDbModTime() {
	time_t mtime = 0;
	struct stat st;

	if(stat(directorydb,&st)==0) mtime = st.st_mtime;

	return mtime;
}