/*! \file pibasetransfer.h
 * \ingroup IO
 * \~\brief
 * \~english Base class for reliable send and receive data in fixed packets with error correction, pause and resume
 * \~russian Базовый класс для надежного обмена данными с помощью фиксированных пакетов с коррекцией ошибок и паузой
 */
/*
    PIP - Platform Independent Primitives
    Base class for reliable send and receive data in fixed packets with error correction, pause and resume
    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 Lesser 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 Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef PIBASETRANSFER_H
#define PIBASETRANSFER_H

#include "picrc.h"
#include "pidiagnostics.h"

//! \~english Base class for reliable send and receive data in fixed packets with error correction, pause and resume
//! \~russian Базовый класс для надежного обмена данными с помощью фиксированных пакетов с коррекцией ошибок и паузой
class PIP_EXPORT PIBaseTransfer: public PIObject {
	PIOBJECT_SUBCLASS(PIBaseTransfer, PIObject);

public:
	//! \~english Constructs empty transfer
	//! \~russian Создает пустой transfer
	PIBaseTransfer();

	//! \~english Destructor
	//! \~russian Деструктор
	~PIBaseTransfer();

#pragma pack(push, 1)
	//! \~english Packet header structure
	//! \~russian Структура заголовка пакета
	struct PIP_EXPORT PacketHeader {
		uint sig;
		int type; // PacketType
		int session_id;
		uint id;
		uint crc;
		//! \~english Check if signature is valid
		//! \~russian Проверка валидности подписи
		bool check_sig() { return (sig == signature); }
	};

	//! \~english Part information structure
	//! \~russian Структура информации о части
	struct PIP_EXPORT Part {
		//! \~english Constructor
		//! \~russian Конструктор
		Part(uint id_ = 0, ullong size_ = 0, ullong start_ = 0): id(id_), size(size_), start(start_) {}
		uint id;
		ullong size;
		ullong start;
	};
#pragma pack(pop)

	//! \~english Stop sending data
	//! \~russian Остановить отправку данных
	void stopSend();

	//! \~english Stop receiving data
	//! \~russian Остановить прием данных
	void stopReceive();

	//! \~english Check if currently sending
	//! \~russian Проверка, идет ли отправка
	bool isSending() const { return is_sending; }

	//! \~english Check if currently receiving
	//! \~russian Проверка, идет ли прием
	bool isReceiving() const { return is_receiving; }

	//! \~english Check if paused
	//! \~russian Проверка, на паузе ли
	bool isPause() const { return is_pause; }

	//! \~english Set pause state
	//! \~russian Установить состояние паузы
	void setPause(bool pause_);

	//! \~english Set packet size
	//! \~russian Установить размер пакета
	void setPacketSize(int size) { packet_size = size; }

	//! \~english Get packet size
	//! \~russian Получить размер пакета
	int packetSize() const { return packet_size; }

	//! \~english Set timeout in seconds
	//! \~russian Установить таймаут в секундах
	void setTimeout(double sec);

	//! \~english Get timeout in seconds
	//! \~russian Получить таймаут в секундах
	double timeout() const { return timeout_; }

	//! \~english Enable/disable CRC check
	//! \~russian Включить/выключить проверку CRC
	void setCRCEnabled(bool en = true) { crc_enabled = en; }

	//! \~english Check if CRC is enabled
	//! \~russian Проверка, включен ли CRC
	bool isCRCEnabled() const { return crc_enabled; }

	//! \~english Get state as string
	//! \~russian Получить состояние в виде строки
	PIString stateString() const { return state_string; }

	//! \~english Get packet map as string
	//! \~russian Получить карту пакетов в виде строки
	PIString packetMap() const { return pm_string; }

	//! \~english Get total bytes count
	//! \~russian Получить общее количество байт
	llong bytesAll() const { return bytes_all; }

	//! \~english Get current bytes count
	//! \~russian Получить текущее количество байт
	llong bytesCur() const { return bytes_cur; }

	//! \~english Get diagnostics object
	//! \~russian Получить объект диагностики
	const PIDiagnostics & diagnostic() { return diag; }

	//! \~english Get packet signature
	//! \~russian Получить подпись пакета
	static uint packetSignature() { return signature; }

	EVENT_HANDLER1(void, received, PIByteArray, data);
	EVENT_HANDLER(void, stop) {
		stopSend();
		stopReceive();
	}
	EVENT_HANDLER(void, pause) { setPause(true); }
	EVENT_HANDLER(void, resume) { setPause(false); }

	EVENT(receiveStarted);
	EVENT(paused);
	EVENT(resumed);
	EVENT1(receiveFinished, bool, ok);
	EVENT(sendStarted);
	EVENT1(sendFinished, bool, ok);
	EVENT1(sendRequest, PIByteArray &, data);

protected:
	void buildSession(PIVector<Part> parts);
	virtual PIByteArray buildPacket(Part fi)                               = 0;
	virtual void receivePart(Part fi, PIByteArray ba, PIByteArray pheader) = 0;
	virtual void beginReceive() { ; }
	virtual PIByteArray customHeader() { return PIByteArray(); }
	bool send_process();

	uint packet_header_size, part_header_size;
	bool break_, is_sending, is_receiving, is_pause;
	PIString state_string;
	llong bytes_all, bytes_cur;

private:
	enum PacketType {
		pt_Unknown,
		pt_Data,
		pt_ReplySuccess,
		pt_ReplyInvalid,
		pt_Break,
		pt_Start,
		pt_Pause
	};

#pragma pack(push, 1)
	struct PIP_EXPORT StartRequest {
		uint packets;
		ullong size;
	};
#pragma pack(pop)

	BINARY_STREAM_FRIEND(PIBaseTransfer::StartRequest);

	void processData(int id, PIByteArray & data);
	PIByteArray build_packet(int id);
	int checkSession();
	void sendBreak(int session_id);
	void sendReply(PacketType reply);
	bool getStartRequest();
	bool finish_send(bool ok);
	void finish_receive(bool ok, bool quet = false);

	static const uint signature;
	int packet_size, packets_count;
	double timeout_;
	PIVector<PIVector<Part>> session;
	PIVector<PacketType> replies;
	PITimeMeasurer send_tm, pause_tm;
	PacketHeader header;
	CRC_16 crc;
	int send_queue;
	int send_up;
	PIDiagnostics diag;
	PIMutex mutex_session;
	PIMutex mutex_send;
	PIMutex mutex_header;
	bool crc_enabled;
	PIString pm_string;
};


BINARY_STREAM_WRITE(PIBaseTransfer::PacketHeader) {
	s << v.sig << v.type << v.session_id << v.id << v.crc;
	return s;
}
BINARY_STREAM_READ(PIBaseTransfer::PacketHeader) {
	s >> v.sig >> v.type >> v.session_id >> v.id >> v.crc;
	return s;
}

BINARY_STREAM_WRITE(PIBaseTransfer::Part) {
	s << v.id << v.size << v.start;
	return s;
}
BINARY_STREAM_READ(PIBaseTransfer::Part) {
	s >> v.id >> v.size >> v.start;
	return s;
}

BINARY_STREAM_WRITE(PIBaseTransfer::StartRequest) {
	s << v.packets << v.size;
	return s;
}
BINARY_STREAM_READ(PIBaseTransfer::StartRequest) {
	s >> v.packets >> v.size;
	return s;
}

inline PICout operator<<(PICout s, const PIBaseTransfer::Part & v) {
	s.saveAndSetControls(0);
	s << "Part(\"" << v.id << "\", " << PIString::readableSize(v.start) << " b | " << PIString::readableSize(v.size) << " b)";
	s.restoreControls();
	return s;
}


#endif // PIBASETRANSFER_H