/*************************************************************************/
/*  file_access_unix.cpp                                                 */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2016 Juan Linietsky, Ariel Manzur.                 */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/
#include "file_access_unix.h"

#if defined(UNIX_ENABLED) || defined(LIBC_FILEIO_ENABLED)

#include <sys/types.h>
#include <sys/stat.h>
#include "print_string.h"
#include "core/os/os.h"

#ifndef ANDROID_ENABLED
#include <sys/statvfs.h>
#endif

#ifdef MSVC
 #define S_ISREG(m) ((m)&_S_IFREG)
#endif
#ifndef S_ISREG
 #define S_ISREG(m) ((m) & S_IFREG)
#endif

void FileAccessUnix::check_errors() const {

	ERR_FAIL_COND(!f);

	if (feof(f)) {

		last_error=ERR_FILE_EOF;
	}

}

Error FileAccessUnix::_open(const String& p_path, int p_mode_flags) {

	if (f)
		fclose(f);
	f=NULL;

	path=fix_path(p_path);
	//printf("opening %ls, %i\n", path.c_str(), Memory::get_static_mem_usage());

	ERR_FAIL_COND_V(f,ERR_ALREADY_IN_USE);
	const char* mode_string;

	if (p_mode_flags==READ)
		mode_string="rb";
	else if (p_mode_flags==WRITE)
		mode_string="wb";
	else if (p_mode_flags==READ_WRITE)
		mode_string="rb+";
	else if (p_mode_flags==WRITE_READ)
		mode_string="wb+";
	else
		return ERR_INVALID_PARAMETER;

	/* pretty much every implementation that uses fopen as primary
	   backend (unix-compatible mostly) supports utf8 encoding */

	//printf("opening %s as %s\n", p_path.utf8().get_data(), path.utf8().get_data());
	struct stat st;
	if (stat(path.utf8().get_data(),&st) == 0) {

		if (!S_ISREG(st.st_mode))
			return ERR_FILE_CANT_OPEN;

	};

	if (is_backup_save_enabled() && p_mode_flags&WRITE && !(p_mode_flags&READ)) {
		save_path=path;
		path=path+".tmp";
		//print_line("saving instead to "+path);
	}

	f=fopen(path.utf8().get_data(),mode_string);

	if (f==NULL) {
		last_error=ERR_FILE_CANT_OPEN;
		return ERR_FILE_CANT_OPEN;
	} else {
		last_error=OK;
		flags=p_mode_flags;
		return OK;
	}

}
void FileAccessUnix::close() {

	if (!f)
		return;
	fclose(f);
	f = NULL;
	if (close_notification_func) {
		close_notification_func(path,flags);
	}
	if (save_path!="") {

		//unlink(save_path.utf8().get_data());
		//print_line("renaming..");
		int rename_error = rename((save_path+".tmp").utf8().get_data(),save_path.utf8().get_data());
		save_path="";
		ERR_FAIL_COND( rename_error != 0);
	}


}
bool FileAccessUnix::is_open() const{

	return (f!=NULL);
}
void FileAccessUnix::seek(size_t p_position) {

	ERR_FAIL_COND(!f);

	last_error=OK;
	if ( fseek(f,p_position,SEEK_SET) )
		check_errors();
}
void FileAccessUnix::seek_end(int64_t p_position)  {

	ERR_FAIL_COND(!f);
	if ( fseek(f,p_position,SEEK_END) )
		check_errors();
}
size_t FileAccessUnix::get_pos() const{


	size_t aux_position=0;
	if ( !(aux_position = ftell(f)) ) {
		check_errors();
	};
	return aux_position;
}
size_t FileAccessUnix::get_len() const{


	ERR_FAIL_COND_V(!f,0);

	FileAccessUnix *fau = const_cast<FileAccessUnix*>(this);
	int pos = fau->get_pos();
	fau->seek_end();
	int size = fau->get_pos();
	fau->seek(pos);

	return size;
}

bool FileAccessUnix::eof_reached() const{

	return last_error==ERR_FILE_EOF;
}

uint8_t FileAccessUnix::get_8() const{

	ERR_FAIL_COND_V(!f,0);
	uint8_t b;
	if (fread(&b,1,1,f) == 0) {
		check_errors();
	};

	return b;
}

int FileAccessUnix::get_buffer(uint8_t *p_dst, int p_length) const {

	ERR_FAIL_COND_V(!f,-1);
	int read = fread(p_dst, 1, p_length, f);
	check_errors();
	return read;
};

Error FileAccessUnix::get_error() const{

	return last_error;
}

void FileAccessUnix::store_8(uint8_t p_dest) {

	ERR_FAIL_COND(!f);
	fwrite(&p_dest,1,1,f);

}


bool FileAccessUnix::file_exists(const String &p_path) {

	FILE *g;
	//printf("opening file %s\n", p_fname.c_str());
	String filename=fix_path(p_path);
	g=fopen(filename.utf8().get_data(),"rb");
	if (g==NULL) {

		return false;
	} else {

		fclose(g);
		return true;
	}
}

uint64_t FileAccessUnix::_get_modified_time(const String &p_file) {

	String file=fix_path(p_file);
	struct stat flags;
	bool success = 	(stat(file.utf8().get_data(),&flags)==0);

	if (success) {
		return flags.st_mtime;
	} else {
		print_line("ERROR IN: "+p_file);

		ERR_FAIL_V(0);
	};

}

FileAccess * FileAccessUnix::create_libc() {

	return memnew( FileAccessUnix );
}

CloseNotificationFunc FileAccessUnix::close_notification_func=NULL;

FileAccessUnix::FileAccessUnix() {

	f=NULL;
	flags=0;
	last_error=OK;

}
FileAccessUnix::~FileAccessUnix() {

	close();

}

#endif