// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only

#ifndef QMODBUSCLIENT_P_H
#define QMODBUSCLIENT_P_H

#include <QtCore/qtimer.h>
#include <QtSerialBus/qmodbusclient.h>
#include <QtSerialBus/qmodbuspdu.h>

#include <private/qmodbusdevice_p.h>

#include <QtCore/qpointer.h>

#include <limits.h>

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

QT_BEGIN_NAMESPACE

class Q_AUTOTEST_EXPORT QModbusClientPrivate : public QModbusDevicePrivate
{
    Q_DECLARE_PUBLIC(QModbusClient)

public:
    QModbusReply *sendRequest(const QModbusRequest &request, int serverAddress,
                              const QModbusDataUnit *const unit);
    QModbusRequest createReadRequest(const QModbusDataUnit &data) const;
    QModbusRequest createWriteRequest(const QModbusDataUnit &data) const;
    QModbusRequest createRWRequest(const QModbusDataUnit &read, const QModbusDataUnit &write) const;

    bool processResponse(const QModbusResponse &response, QModbusDataUnit *data);

    bool processReadCoilsResponse(const QModbusResponse &response, QModbusDataUnit *data);
    bool processReadDiscreteInputsResponse(const QModbusResponse &response, QModbusDataUnit *data);
    bool collateBits(const QModbusPdu &pdu, QModbusDataUnit::RegisterType type, QModbusDataUnit *data);

    bool processReadHoldingRegistersResponse(const QModbusResponse &response, QModbusDataUnit *data);
    bool processReadInputRegistersResponse(const QModbusResponse &response, QModbusDataUnit *data);
    bool collateBytes(const QModbusPdu &pdu, QModbusDataUnit::RegisterType type, QModbusDataUnit *data);

    bool processWriteSingleCoilResponse(const QModbusResponse &response, QModbusDataUnit *data);
    bool processWriteSingleRegisterResponse(const QModbusResponse &response,
                                            QModbusDataUnit *data);
    bool collateSingleValue(const QModbusPdu &pdu, QModbusDataUnit::RegisterType type,
                         QModbusDataUnit *data);

    bool processWriteMultipleCoilsResponse(const QModbusResponse &response, QModbusDataUnit *data);
    bool processWriteMultipleRegistersResponse(const QModbusResponse &response,
                                               QModbusDataUnit *data);
    bool collateMultipleValues(const QModbusPdu &pdu, QModbusDataUnit::RegisterType type,
                          QModbusDataUnit *data);

    bool processReadWriteMultipleRegistersResponse(const QModbusResponse &response,
                                                  QModbusDataUnit *data);

    virtual QModbusReply *enqueueRequest(const QModbusRequest &, int, const QModbusDataUnit &,
                                         QModbusReply::ReplyType) {
        return nullptr;
    }
    // TODO: Review once we have a transport layer in place.
    virtual bool isOpen() const { return false; }

    int m_numberOfRetries = 3;
    int m_responseTimeoutDuration = 1000;

    struct QueueElement {
        QueueElement() = default;
        QueueElement(QModbusReply *r, const QModbusRequest &req, const QModbusDataUnit &u, int num,
                int timeout = -1)
            : reply(r), requestPdu(req), unit(u), numberOfRetries(num)
        {
            if (timeout >= 0) {
                // always the case for TCP
                timer = QSharedPointer<QTimer>::create();
                timer->setSingleShot(true);
                timer->setInterval(timeout);
            }
        }
        bool operator==(const QueueElement &other) const {
            return reply == other.reply;
        }

        QPointer<QModbusReply> reply;
        QModbusRequest requestPdu;
        QModbusDataUnit unit;
        int numberOfRetries;
        QSharedPointer<QTimer> timer;
        QByteArray adu;
        qint64 bytesWritten = 0;
        qint32 m_timerId = INT_MIN;
    };
    void processQueueElement(const QModbusResponse &pdu, const QueueElement &element);
};

QT_END_NAMESPACE

#endif // QMODBUSCLIENT_P_H

