/*
	PIP - Platform Independent Primitives
	Class for write binary data to logfile, and read or playback this data
	Copyright (C) 2014  Andrey Bychkov work.a.b@yandex.ru

	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 "pibinarylog.h"


/*! \class PIBinaryLog
 * \brief Class for read and write binary data to logfile, and playback this data in realtime
 *
 * \section PIBinaryLog_sec0 Synopsis
 * Binary Log is a file with simle header, where you can read and write some binary data.
 * Any written data include special header with ID, size and timestamp.
 * This header provides separation different messages from the one file by choosing different IDs.
 * With \a filterID or special functions, like \a readBinLog() you can choose IDs what you want to read.
 * With function \a writeBinLog() or \a setDefaultID() you can choose ID that mark you data.
 * By default ID = 1, and \a filterID is empty, that mean you read any ID without filtering.
 * ThreadedRead provide you playback data, with delay that you write data.
 * You can choose realtime playbak or variable speed play back by set \a PlayMode.
 *
 * \section PIBinaryLog_sec1 Basic usage
 * This class provide all functions of \a PIIODevice, such \a open(), \a close(),
 * \a read() ,\a write(), and threaded read/write.
 * function \a setLogDir() need to set directory for BinLog files
 * function \a createNewFile() need to create new binlog file
 * function \a restart() need start from the begining of binlog file
 *
 */

REGISTER_DEVICE(PIBinaryLog);


PIBinaryLog::PIBinaryLog() {
	binlog_sig[0] = 'B';
	binlog_sig[1] = 'I';
	binlog_sig[2] = 'N';
	binlog_sig[3] = 'L';
	binlog_sig[4] = 'O';
	binlog_sig[5] = 'G';
	setThreadedReadBufferSize(65536);
	is_started = false;
	setPlaySpeed(1.f);
	setDefaultID(1);
	setPlayMode(PlayVariableSpeed);
	setLogDir(PIString());
	setFilePrefix(PIString());
	setRapidStart(false);
}


bool PIBinaryLog::openDevice() {
	lastrecord.timestamp = PISystemTime();
	lastrecord.id = 0;
	is_started = false;
	is_thread_ok = true;
	if (mode_ == ReadWrite) {
		piCoutObj << "Error: ReadWrite mode not supported, use WriteOnly or ReadOnly";
		return false;
	}
	if (!file.open(path(), mode_))
		return false;
	setName(path());
	if (mode_ == WriteOnly) {
		file.resize(0);
		if (!writeFileHeader()) {
			piCoutObj << "Error: Can't write binlog file header";
			return false;
		}
		is_started = true;
	}
	if (mode_ == ReadOnly) {
		if (file.isEmpty()) {
			piCoutObj << "Error: File is null";
			fileError();
			return false;
		}
		if (!checkFileHeader()) {
			fileError();
			return false;
		}
		if (isEmpty()) piCoutObj << "Error: Empty BinLog file";
		//		startlogtime = PISystemTime::current();
		play_time = 0;
		//		nextrecord = readsRecord();
		if (!rapidStart()) is_started = true;
	}
	startlogtime = PISystemTime::current();
	return true;
}


bool PIBinaryLog::closeDevice() {
	if (canWrite() && isEmpty()) {
		file.remove();
		return true;
	}
    return file.close();
}


bool PIBinaryLog::threadedRead(uchar *readed, int size) {
	is_thread_ok = false;
	PISystemTime pt;
	double delay;
	switch (playMode()) {
	case PlayRealTime:
		pt = PISystemTime::current() - startlogtime;
//		if (real_speedX > 0)
//			for (int i=0; i<real_speedX-1; i++) pt +=  pt;
//		piCout << pt << lastrecord.timestamp << lastrecord.timestamp - pt;
		if (is_started) {
			if (lastrecord.timestamp > pt)
				(lastrecord.timestamp - pt).sleep();
		} else {
			startlogtime = PISystemTime::current() - lastrecord.timestamp;
			is_started = true;
		}
		//	int delay = piRoundd(lastread_timestamp.toMilliseconds() - (PISystemTime::current() - startlogtime).toMilliseconds());
		break;
	case PlayVariableSpeed:
		delay = lastrecord.timestamp.toMilliseconds() - play_time;
		delay /= playSpeed();
		if (is_started) {
			if (delay > 0)
				PISystemTime::fromMilliseconds(delay).sleep();
		} else is_started = true;
		play_time = lastrecord.timestamp.toMilliseconds();
		break;
	default:
		return false;
	}
	bool res = PIIODevice::threadedRead(readed, size);
	is_thread_ok = true;
	return res;
}


PIString PIBinaryLog::createNewFile() {
	if (!file.close()) return PIString();
	if (open(logDir() + "/" + filePrefix() + PIDateTime::current().toString("yyyy_MM_dd__hh_mm_ss.binlog"), PIIODevice::WriteOnly))
		return file.path();
	piCoutObj << "Can't create new file, maybe LogDir is invalid.";
	return PIString();
}


int PIBinaryLog::writeBinLog(int id, const void *data, int size) {
	if (size <= 0 || !canWrite()) return -1;
	PIByteArray logdata;
	logdata << id << size << (PISystemTime::current() - startlogtime) << PIByteArray::RawData(data, size);
	int res = file.write(logdata.data(), logdata.size());
	file.flush();
	if (res > 0) return size;
	else return res;
}


PIByteArray PIBinaryLog::readBinLog(int id) {
	if (!canRead()) return PIByteArray();
	BinLogRecord br = readRecord();
	if (br.id == -1) {
		piCoutObj << "End of BinLog file";
		fileEnd();
		return PIByteArray();
	}
	if (id == 0 && br.id > 0) return br.data;
	while (br.id != id && !isEnd()) br = readRecord();
	if (br.id == -1) {
		piCoutObj << "End of BinLog file";
		fileEnd();
		return PIByteArray();
	}
	if (br.id == id) return br.data;
	piCoutObj << "Can't find record with id =" << id;
	return PIByteArray();
}


int PIBinaryLog::readBinLog(int id, void *read_to, int max_size) {
	if (max_size <= 0 || read_to == 0) return -1;
	PIByteArray ba = readBinLog(id);
	if (ba.isEmpty()) return -1;
	int sz = piMini(max_size, ba.size());
	memcpy(read_to, ba.data(), sz);
	return sz;
}



int PIBinaryLog::read(void *read_to, int max_size) {
	//	piCoutObj << "read";
	if (lastrecord.id == -1 || isEnd()) return 0;
	if(!is_thread_ok && lastrecord.id > 0) return lastrecord.data.size();
	if (!canRead()) return -1;
	if (max_size <= 0 || read_to == 0) return -1;
	BinLogRecord br;
	br.id = 0;
	if (filterID.isEmpty()) br = readRecord();
	else {
		while (!filterID.contains(br.id) && !isEnd()) br = readRecord();
	}
	if (br.id == -1) {
		fileEnd();
		piCoutObj << "End of BinLog file";
		//stopThreadedRead();
		return 0;
	}
	if (br.id <= 0) {
		piCoutObj << "Read record error";
		return -1;
	}
	int sz = piMini(max_size, br.data.size());
	memcpy(read_to, br.data.data(), sz);
	return sz;
}


void PIBinaryLog::restart() {
	bool th = isRunning();
	if (th) stopThreadedRead();
	if (!canRead()) return;
	lastrecord.timestamp = PISystemTime();
	lastrecord.id = 0;
	is_thread_ok = true;
	if (rapidStart()) is_started = false;
	else is_started = true;
	play_time = 0;
	file.seekToBegin();
	checkFileHeader();
	startlogtime = PISystemTime::current();
	if (th) startThreadedRead();
}


bool PIBinaryLog::writeFileHeader() {
	if (file.write(&binlog_sig, PIBINARYLOG_SIGNATURE_SIZE) <= 0) return false;
	uchar version = PIBINARYLOG_VERSION;
	if (file.write(&version, 1) <= 0) return false;
	file.flush();
	return true;
}


bool PIBinaryLog::checkFileHeader() {
	uchar read_sig[PIBINARYLOG_SIGNATURE_SIZE];
	for (int i=0; i<PIBINARYLOG_SIGNATURE_SIZE; i++) read_sig[i] = 0;
	if (file.read(read_sig, PIBINARYLOG_SIGNATURE_SIZE) < 0) return false;
	bool correct = true;
	for (int i=0; i<PIBINARYLOG_SIGNATURE_SIZE; i++)
		if (read_sig[i] != binlog_sig[i]) correct = false;
	if (!correct) {
		piCoutObj << "BinLogFile signature is corrupted or invalid file";
		return false;
	}
	uchar read_version = 0;
	if (file.read(&read_version, 1) < 0) return false;
	if (read_version == PIBINARYLOG_VERSION) return true;
	if (read_version == 0)
		piCoutObj << "BinLogFile has invalid version";
	if (read_version < PIBINARYLOG_VERSION)
		piCoutObj << "BinLogFile has too old verion";
	if (read_version > PIBINARYLOG_VERSION)
		piCoutObj << "BinLogFile has too newest version";
	return false;
}


PIBinaryLog::BinLogRecord PIBinaryLog::readRecord() {
	//	piCoutObj << "readRecord";
	PIByteArray ba;
	BinLogRecord br;
	lastrecord.id = 0;
	lastrecord.data.clear();
	lastrecord.timestamp = PISystemTime();
	ba.resize(sizeof(BinLogRecord) - sizeof(PIByteArray));
	if(file.read(ba.data(), ba.size_s()) > 0) {
		ba >> br.id >> br.size >> br.timestamp;
		//		piCoutObj << "read" << br.id << br.size << br.timestamp;
	} else {
		br.id = -1;
		return br;
	}
	if (br.id > 0 && br.size > 0) {
		ba.resize(br.size);
		if(file.read(ba.data(), ba.size_s()) > 0) br.data = ba;
		else br.id = 0;
	} else br.id = 0;
	lastrecord = br;
	if (br.id == 0) fileError();
	return br;
}


PIString PIBinaryLog::constructFullPath() const {
	PIString ret(fullPathPrefix() + "://");
	ret << logDir() << ":" << filePrefix() << ":" << defaultID();
	return ret;
}


void PIBinaryLog::configureFromFullPath(const PIString & full_path) {
	PIStringList pl = full_path.split(":");
	for (int i = 0; i < pl.size_s(); ++i) {
		PIString p(pl[i]);
		switch (i) {
		case 0: setLogDir(p); break;
		case 1: setFilePrefix(p); break;
		case 2: setDefaultID(p.toInt()); break;
		}
	}
}