/*************************************************************************/
/*  file_access.cpp                                                      */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2017 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.h"
#include "globals.h"
#include "os/os.h"
#include "core/io/marshalls.h"
#include "io/md5.h"
#include "io/sha256.h"
#include "core/io/file_access_pack.h"

FileAccess::CreateFunc FileAccess::create_func[ACCESS_MAX]={0,0};

FileAccess::FileCloseFailNotify FileAccess::close_fail_notify=NULL;


bool FileAccess::backup_save=false;

FileAccess *FileAccess::create(AccessType p_access){

	ERR_FAIL_COND_V( !create_func, 0 );
	ERR_FAIL_INDEX_V( p_access,ACCESS_MAX, 0 );

	FileAccess *ret = create_func[p_access]();
	ret->_set_access_type(p_access);
	return ret;
}

bool FileAccess::exists(const String& p_name) {

	if (PackedData::get_singleton()->has_path(p_name))
		return true;

	FileAccess *f=open(p_name,READ);
	if (!f)
		return false;
	memdelete(f);
	return true;


}

void FileAccess::_set_access_type(AccessType p_access) {

	_access_type = p_access;
};

FileAccess *FileAccess::create_for_path(const String& p_path) {

	FileAccess *ret=NULL;
	if (p_path.begins_with("res://")) {

		ret = create(ACCESS_RESOURCES);
	} else if (p_path.begins_with("user://")) {

		ret = create(ACCESS_USERDATA);

	} else {

		ret = create(ACCESS_FILESYSTEM);
	}

	return ret;


}

Error FileAccess::reopen(const String& p_path, int p_mode_flags) {

	return _open(p_path, p_mode_flags);
};


FileAccess *FileAccess::open(const String& p_path, int p_mode_flags, Error *r_error) {

	//try packed data first

	FileAccess *ret=NULL;
	if (!(p_mode_flags&WRITE) && PackedData::get_singleton() && !PackedData::get_singleton()->is_disabled()) {
		ret = PackedData::get_singleton()->try_open_path(p_path);
		if (ret) {
			if (r_error)
				*r_error=OK;
			return ret;
		}
	}

	ret=create_for_path(p_path);
	Error err = ret->_open(p_path,p_mode_flags);

	if (r_error)
		*r_error=err;
	if (err!=OK) {

		memdelete(ret);
		ret=NULL;
	}

	return ret;
}


FileAccess::CreateFunc FileAccess::get_create_func(AccessType p_access) {

	return create_func[p_access];
};

String FileAccess::fix_path(const String& p_path) const {
	//helper used by file accesses that use a single filesystem

	String r_path = p_path.replace("\\", "/");

	switch(_access_type) {

		case ACCESS_RESOURCES: {

			if (GlobalConfig::get_singleton()) {
				if (r_path.begins_with("res://")) {

					String resource_path = GlobalConfig::get_singleton()->get_resource_path();
					if (resource_path != "") {

						return r_path.replace("res:/",resource_path);
					};
					return r_path.replace("res://", "");
				}
			}


		} break;
		case ACCESS_USERDATA: {


			if (r_path.begins_with("user://")) {

				String data_dir=OS::get_singleton()->get_data_dir();
				if (data_dir != "") {

					return r_path.replace("user:/",data_dir);
				};
				return r_path.replace("user://", "");
			}

		} break;
		case ACCESS_FILESYSTEM: {

			return r_path;
		} break;
	}

	return r_path;
}

/* these are all implemented for ease of porting, then can later be optimized */

uint16_t FileAccess::get_16()const {

	uint16_t res;
	uint8_t a,b;

	a=get_8();
	b=get_8();

	if (endian_swap) {

		SWAP( a,b );
	}

	res=b;
	res<<=8;
	res|=a;

	return res;
}
uint32_t FileAccess::get_32() const{

	uint32_t res;
	uint16_t a,b;

	a=get_16();
	b=get_16();

	if (endian_swap) {

		SWAP( a,b );
	}

	res=b;
	res<<=16;
	res|=a;

	return res;
}
uint64_t FileAccess::get_64()const {

	uint64_t res;
	uint32_t a,b;

	a=get_32();
	b=get_32();

	if (endian_swap) {

		SWAP( a,b );
	}

	res=b;
	res<<=32;
	res|=a;

	return res;

}

float FileAccess::get_float() const {

	MarshallFloat m;
	m.i = get_32();
	return m.f;
};

real_t FileAccess::get_real() const {

	if (real_is_double)
		return get_double();
	else
		return get_float();

}

double FileAccess::get_double() const {

	MarshallDouble m;
	m.l = get_64();
	return m.d;
};

String FileAccess::get_line() const {

	CharString line;

	CharType c=get_8();

	while(!eof_reached()) {

		if (c=='\n' || c=='\0') {
			line.push_back(0);
			return String::utf8(line.get_data());
		} else if (c!='\r')
			line.push_back(c);

		c=get_8();
	}
	line.push_back(0);
	return String::utf8(line.get_data());
}

Vector<String> FileAccess::get_csv_line(String delim) const {

	ERR_FAIL_COND_V(delim.length()!=1,Vector<String>());

	String l;
	int qc=0;
	do {
		l+=get_line()+"\n";
		qc=0;
		for(int i=0;i<l.length();i++) {

			if (l[i]=='"')
				qc++;
		}


	} while (qc%2);

	l=l.substr(0, l.length()-1);

	Vector<String> strings;

	bool in_quote=false;
	String current;
	for(int i=0;i<l.length();i++) {

		CharType c = l[i];
		CharType s[2]={0,0};


		if (!in_quote && c==delim[0]) {
			strings.push_back(current);
			current=String();
		} else if (c=='"') {
			if (l[i+1]=='"') {
				s[0]='"';
				current+=s;
				i++;
			} else {

				in_quote=!in_quote;
			}
		} else {
			s[0]=c;
			current+=s;
		}

	}

	strings.push_back(current);

	return strings;
}


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

	int i=0;
	for (i=0; i<p_length && !eof_reached(); i++)
		p_dst[i]=get_8();

	return i;
}

void FileAccess::store_16(uint16_t p_dest) {

	uint8_t a,b;

	a=p_dest&0xFF;
	b=p_dest>>8;

	if (endian_swap) {

		SWAP( a,b );
	}

	store_8(a);
	store_8(b);

}
void FileAccess::store_32(uint32_t p_dest) {


	uint16_t a,b;

	a=p_dest&0xFFFF;
	b=p_dest>>16;

	if (endian_swap) {

		SWAP( a,b );
	}

	store_16(a);
	store_16(b);

}
void FileAccess::store_64(uint64_t p_dest) {

	uint32_t a,b;

	a=p_dest&0xFFFFFFFF;
	b=p_dest>>32;

	if (endian_swap) {

		SWAP( a,b );
	}

	store_32(a);
	store_32(b);

}

void FileAccess::store_real(real_t p_real) {

	if (sizeof(real_t)==4)
		store_float(p_real);
	else
		store_double(p_real);

}

void FileAccess::store_float(float p_dest) {

	MarshallFloat m;
	m.f = p_dest;
	store_32(m.i);
};

void FileAccess::store_double(double p_dest) {

	MarshallDouble m;
	m.d = p_dest;
	store_64(m.l);
};

uint64_t FileAccess::get_modified_time(const String& p_file) {

	FileAccess *fa = create_for_path(p_file);
	ERR_FAIL_COND_V(!fa,0);

	uint64_t mt = fa->_get_modified_time(p_file);
	memdelete(fa);
	return mt;
}

void FileAccess::store_string(const String& p_string) {

	if (p_string.length()==0)
		return;

	CharString cs=p_string.utf8();
	store_buffer((uint8_t*)&cs[0],cs.length());

}

void FileAccess::store_pascal_string(const String& p_string) {

	CharString cs = p_string.utf8();
	store_32(cs.length());
	store_buffer((uint8_t*)&cs[0], cs.length());
};

String FileAccess::get_pascal_string() {

	uint32_t sl = get_32();
	CharString cs;
	cs.resize(sl+1);
	get_buffer((uint8_t*)cs.ptr(),sl);
	cs[sl]=0;

	String ret;
	ret.parse_utf8(cs.ptr());

	return ret;
};


void FileAccess::store_line(const String& p_line) {

	store_string(p_line);
	store_8('\n');
}

void FileAccess::store_buffer(const uint8_t *p_src,int p_length) {

	for (int i=0;i<p_length;i++)
		store_8(p_src[i]);
}

Vector<uint8_t> FileAccess::get_file_as_array(const String& p_file) {

	FileAccess *f=FileAccess::open(p_file,READ);
	ERR_FAIL_COND_V(!f,Vector<uint8_t>());
	Vector<uint8_t> data;
	data.resize(f->get_len());
	f->get_buffer(data.ptr(),data.size());
	memdelete(f);
	return data;


}

String FileAccess::get_md5(const String& p_file) {

	FileAccess *f=FileAccess::open(p_file,READ);
	if (!f)
		return String();

	MD5_CTX md5;
	MD5Init(&md5);

	unsigned char step[32768];

	while(true) {

		int br = f->get_buffer(step,32768);
		if (br>0) {

			MD5Update(&md5,step,br);
		}
		if (br < 4096)
			break;

	}

	MD5Final(&md5);

	String ret = String::md5(md5.digest);



	memdelete(f);
	return ret;

}

String FileAccess::get_sha256(const String& p_file) {

	FileAccess *f=FileAccess::open(p_file,READ);
	if (!f)
		return String();

	sha256_context sha256;
	sha256_init(&sha256);

	unsigned char step[32768];

	while(true) {

		int br = f->get_buffer(step,32768);
		if (br>0) {

			sha256_hash(&sha256,step,br);
		}
		if (br < 4096)
			break;

	}

	unsigned char hash[32];

	sha256_done(&sha256, hash);

	memdelete(f);
	return String::hex_encode_buffer(hash, 32);

}

FileAccess::FileAccess() {

	endian_swap=false;
	real_is_double=false;
	_access_type=ACCESS_FILESYSTEM;
};
