/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */

#include "ultima/nuvie/core/nuvie_defs.h"
#include "ultima/nuvie/files/nuvie_io_file.h"
#include "engines/metaengine.h"
#include "common/system.h"
#include "common/config-manager.h"
#include "engines/engine.h"

namespace Ultima {
namespace Nuvie {

NuvieIOFileRead::~NuvieIOFileRead() {
	close();
}

bool NuvieIOFileRead::open(const Common::Path &filename) {
	if (isOpen())
		// We already have a file open, lets bail.
		return false;

	// Handle any relative files under the game path, such as for FM-Towns sound. Though path
	// delimiters can also be used for resources in ultima.dat

        Common::StringArray components = filename.splitComponents();
        if (components.empty()) {
                return false;
        }

	if (components.size() >= 2) {
		Common::FSNode node(ConfMan.getPath("path"));
		for(const auto &c : components) {
			node = node.getChild(c);
			if (!node.exists())
				break;
		}
		if (node.exists())
			_srcFile.open(node);
	}

	if (!_srcFile.isOpen())
		_srcFile.open(filename);

	if (!_srcFile.isOpen()) {
		DEBUG(0, LEVEL_ERROR, "Failed opening '%s'\n", filename.toString().c_str());
		return false;
	}

	_file = &_srcFile;
	size = _srcFile.size();
	pos = 0;

	return true;
}

bool NuvieIOFileRead::open(Common::InSaveFile *saveFile) {
	assert(saveFile);
	_file = saveFile;

	size = _file->size();
	pos = 0;

	return true;
}

void NuvieIOFileRead::close() {
	if (_srcFile.isOpen())
		_srcFile.close();
	_file = nullptr;

	NuvieIO::close();
}

void NuvieIOFileRead::seek(uint32 new_pos) {
	if (isOpen() && new_pos <= size) {
		_file->seek(new_pos);
		pos = new_pos;
	}
}

uint8 NuvieIOFileRead::read1() {
	if (pos > size - 1)
		return 0;

	pos++;

	return _file->readByte();
}

uint16 NuvieIOFileRead::read2() {
	if (pos > size - 2)
		return 0;

	pos += 2;
	return _file->readUint16LE();
}

uint32 NuvieIOFileRead::read4() {
	if (pos > size - 4)
		return 0;

	pos += 4;
	return _file->readUint32LE();
}

bool NuvieIOFileRead::readToBuf(unsigned char *buf, uint32 buf_size) {
	if (pos + buf_size > size)
		return false;

	_file->read(buf, buf_size);
	pos += buf_size;
	return true;
}


// NuvieIOFileWrite
//

NuvieIOFileWrite::NuvieIOFileWrite() : _saveFileData(DisposeAfterUse::YES),
		_file(nullptr), _saveFile(nullptr), _isAutosave(false) {
}

NuvieIOFileWrite::~NuvieIOFileWrite() {
	close();
}

bool NuvieIOFileWrite::open(const Common::Path &filename) {
	if (isOpen())
		// We already have an open file
		return false;

	// Ensure it's a relative path, that we can open for writing using a DumpFile
	assert(!filename.getParent().empty());

	if (!_dumpFile.open(filename, true)) {
		DEBUG(0, LEVEL_ERROR, "Failed opening '%s'\n", filename.toString().c_str());
		return false;
	}

	_file = &_dumpFile;
	return true;
}

bool NuvieIOFileWrite::open(const Common::String &filename, bool isAutosave) {
	if (isOpen())
		// We already have an open file
		return false;

	// Singular file, so open it as a save file
	_saveFile = g_system->getSavefileManager()->openForSaving(filename, false);
	assert(_saveFile);

	// Point _file to the _saveFileData member for initial writing,
	// since save files don't allow seeking
	_file = &_saveFileData;
	_isAutosave = isAutosave;

	size = 0;
	pos = 0;

	return true;
}

void NuvieIOFileWrite::close() {
	if (!isOpen()) {
		// Nothing needed
	} else if (_saveFile) {
		// Writing using savefile interface, so flush out data
		_saveFile->write(_saveFileData.getData(), _saveFileData.size());
		g_engine->getMetaEngine()->appendExtendedSave(_saveFile, g_engine->getTotalPlayTime(), _description, _isAutosave);

		_saveFile->finalize();
		delete _saveFile;
		_saveFile = nullptr;
	} else {
		// Writing to a dump file, so simply close it
		_dumpFile.close();
	}

	_file = nullptr;
}

void NuvieIOFileWrite::seek(uint32 new_pos) {
	if (isOpen() && new_pos <= size) {
		_file->seek(new_pos);
		pos = new_pos;
	}
}

bool NuvieIOFileWrite::write1(uint8 src) {
	if (!isOpen())
		return false;

	_file->writeByte(src);
	++pos;

	if (pos > size)
		size = pos;

	return true;
}

bool NuvieIOFileWrite::write2(uint16 src) {
	if (!isOpen())
		return false;

	_file->writeUint16LE(src);
	pos += 2;

	if (pos > size)
		size = pos;

	return true;
}

bool NuvieIOFileWrite::write4(uint32 src) {
	if (!isOpen())
		return false;

	_file->writeUint32LE(src);
	pos += 4;

	if (pos > size)
		size = pos;

	return true;
}

uint32 NuvieIOFileWrite::writeBuf(const unsigned char *src, uint32 src_size) {
	if (!isOpen())
		return false;

	pos += src_size;
	if (pos > size)
		size = pos;

	return (_file->write(src, src_size));
}

uint32 NuvieIOFileWrite::write(NuvieIO *src) {
	return 0;
}

} // End of namespace Nuvie
} // End of namespace Ultima