// SPDX-License-Identifier: LGPL-3.0-or-later

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* nymea-zigbee
* Zigbee integration module for nymea
*
* Copyright (C) 2013 - 2024, nymea GmbH
* Copyright (C) 2024 - 2025, chargebyte austria GmbH
*
* This file is part of nymea-zigbee.
*
* nymea-zigbee 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.
*
* nymea-zigbee 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 nymea-zigbee. If not, see <https://www.gnu.org/licenses/>.
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#ifndef ZIGBEEINTERFACE_H
#define ZIGBEEINTERFACE_H

#include <QObject>
#include <QTimer>
#include <QSerialPort>

#include "zigbee.h"
#include "zigbeeinterfacemessage.h"

class ZigbeeInterface : public QObject
{
    Q_OBJECT
public:
    enum ReadingState {
        WaitForStart,
        WaitForTypeMsb,
        WaitForTypeLsb,
        WaitForLenghtMsb,
        WaitForLengthLsb,
        WaitForCrc,
        WaitForData
    };
    Q_ENUM(ReadingState)

    explicit ZigbeeInterface(QObject *parent = nullptr);
    ~ZigbeeInterface();

    bool available() const;
    QString serialPort() const;

private:
    QTimer *m_reconnectTimer = nullptr;
    QSerialPort *m_serialPort = nullptr;
    QByteArray m_messageBuffer;
    QByteArray m_unhandledBuffer;
    bool m_available = false;

    // Message parsing
    ReadingState m_readingState = WaitForStart;
    quint8 m_crcValue;
    quint8 m_currentValue;
    quint16 m_messageTypeValue;
    quint16 m_lengthValue;
    QByteArray m_data;
    bool m_escapeDetected;

    quint8 calculateCrc(const quint16 &messageTypeValue, const quint16 &lenghtValue, const QByteArray &data);

    void streamByte(quint8 byte, bool specialCharacter = false);
    void setAvailable(bool available);
    void setReadingState(const ReadingState & state);

signals:
    void availableChanged(bool available);
    void messageReceived(const ZigbeeInterfaceMessage &message);

private slots:
    void onReconnectTimeout();
    void onReadyRead();
    void onError(const QSerialPort::SerialPortError &error);

public slots:
    bool enable(const QString &serialPort = "/dev/ttyS0", qint32 baudrate = 115200);
    void disable();

    void sendMessage(const ZigbeeInterfaceMessage &message);

};

#endif // ZIGBEEINTERFACE_H