/*!
 *
 * Copyright (c) 2020-2024 Diality Inc. - All Rights Reserved.
 * \copyright
 * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 *
 * \file    FrameInterface.cpp
 * \author  (last)      Behrouz NematiPour
 * \date    (last)      30-Jul-2023
 * \author  (original)  Behrouz NematiPour
 * \date    (original)  26-Aug-2020
 *
 */
#include "FrameInterface.h"

// Qt
#include <QThread>
#include <QApplication>
#include <QTime>

// Project
#include "Logger.h"
#include "MessageDispatcher.h"
#include "CanInterface.h"

// namespace
using namespace Can;

/*!
 * \brief FrameInterface::FrameInterface
 * \details Constructor
 * \param   parent - QObject parent owner object.
 *          Qt handles the children destruction by their parent objects life-cycle.
 */
FrameInterface::FrameInterface(QObject *parent) : QObject(parent) { }

/*!
 * \brief Message Handler initializer
 */
bool FrameInterface::init()
{
    if ( _init ) return false;
    _init = true;

    initConnections();

    startTimer(1, Qt::PreciseTimer);

    LOG_DEBUG(QString("%1 Initialized").arg(metaObject()->className()));

    return true;
}

/*!
 * \brief   FrameInterface::init
 * \details Initialized the Class by calling the init() method first
 *          And initializes the thread vThread by calling initThread
 *          on success init().
 * \param   vThread - the thread
 * \return  returns the return value of the init() method
 */
bool FrameInterface::init(QThread &vThread)
{
    if ( ! init() ) return false;
    initThread(vThread);
    return true;
}

/*!
 * \brief   FrameInterface::quit
 * \details quits the class
 *          Calls quitThread
 */
void FrameInterface::quit()
{
    quitThread(); // validated
}

/*!
 * \brief   FrameInterface connections definition
 * \details Initializes the required signal/slot connection between this class and other objects
 *          to be able to communicate.
 */
void FrameInterface::initConnections()
{
    // From GUI
    connect(&_MessageDispatcher, SIGNAL(didFrameTransmit(Can_Id, const QByteArray   &)),
            this               ,   SLOT( onFrameTransmit(Can_Id, const QByteArray   &)));

    // From CAN
    connect(&_CanInterface     , SIGNAL( didFrameReceive(        const QCanBusFrame &)),
            this               ,   SLOT(  onFrameReceive(        const QCanBusFrame &)));
    connect(&_CanInterface     , SIGNAL( didFrameWritten(qint64                      )),
            this               ,   SLOT(  onFrameWritten(qint64                      )));
}

/*!
 * \brief   ApplicationController::initThread
 * \details Moves this object into the thread vThread.
 *          And checks that this method is called from main thread.
 *          Also connects quitThread to application aboutToQuit.
 * \param   vThread - the thread
 */
void FrameInterface::initThread(QThread &vThread)
{
    // runs in main thread
    Q_ASSERT_X(QThread::currentThread() == qApp->thread() , __func__, "The Class initialization must be done in Main Thread" );
    _thread = &vThread;
    _thread->setObjectName(QString("%1_Thread").arg(metaObject()->className()));
    connect(qApp, SIGNAL(aboutToQuit()), this, SLOT(quit()));
    moveToThread(_thread);
    _thread->start();
}

/*!
 * \brief   FrameInterface::quitThread
 * \details Moves this object to main thread to be handled by QApplication
 *          And to be destroyed there.
 */
void FrameInterface::quitThread()
{
    if ( ! _thread ) return;

    // runs in thread
    moveToThread(qApp->thread()); // validated
}

/*!
 * \brief   FrameInterface::transmitFrame
 * \details Prepares a frame to be transmitted
 *          and emit signal didFrameTransmit with the frame as its argument
 * \param   vFrameId - Channel id of the CANBus frame
 * \param   vData    - The Data this frame is going to carry
 * \note    This frame is created by MessageBuilder
 *          and it can be one of the frames of a message
 *          which has been chopped into frames.
 */
void FrameInterface::transmitFrame(Can_Id vCan_Id, const QByteArray &vData)
{
    QCanBusFrame mFrame;
    mFrame.setFrameId(vCan_Id);
    if (vData.length() > Can::eLenCanFrame) {
        LOG_DEBUG(QString("Payload cannot be larger than %1 bytes").arg(Can::eLenCanFrame));
        return;
    }
    mFrame.setPayload(vData);
    emit didFrameTransmit(mFrame);
}

/*!
 * \brief   FrameInterface::checkChannel
 * \details Checks for the channel id of the received frame
 *          which needs to be handled or ignored.
 * \param   vFrameId - Channel id of the frame
 * \param   vOK      - will be set to true if the channel
 *          is valid and a variable has been passed to
 * \return  The Category if the channels from the UI
 *          perspective FrameInterface::ChannelGroup
 */
FrameInterface::ChannelGroup FrameInterface::checkChannel(quint32 vFrameId, bool *vOK, bool *vDebugChanngel)
{
    bool ok = true;
    bool debugChannel = false;

    FrameInterface::ChannelGroup channelGroup = ChannelGroup::eChannel_Unknown;
    switch (vFrameId) {
    case eDialin_TD         :
    case eTD_Dialin         :
    case eDialin_DD         :
    case eDD_Dialin         :
    case eDialin_UI         :
    case eUI_Dialin         :
        if ( gDisableDialinUnhandled ) {
            channelGroup = ChannelGroup::eChannel_Ignores;
        } else {
            channelGroup = ChannelGroup::eChannel_Listens;
        }
        debugChannel =   gDisableDialinUnhandled; // if debug channel is true, the raw can message in logged in the service log.
        ok           = ! gDisableDialinUnhandled; // if ok is true then it will be interpreted as unhandled messages.
        break;

    // these channels will be used for testing for now.
    case eChlid_TD_DD       :
    case eChlid_DD_TD       :
    case eChlid_DD_FP       :
    case eChlid_FP_DD       :
        //channelGroup = ChannelGroup::eChannel_Ignores;
        //break;

    case eChlid_TD_UI       :
    case eChlid_TD_Alarm    :
    case eChlid_TD_Sync     :
  //case eChlid_DD_UI       : // has duplicate value as eChlid_DD_Sync
    case eChlid_DD_Alarm    :
    case eChlid_DD_Sync     :
  //case eChlid_FP_UI       : // has duplicate value as eChlid_FP_Sync, Only in α, will be removed in ꞵ
    case eChlid_FP_Alarm    : // Only in α, will be removed in ꞵ
    case eChlid_FP_Sync     : // Only in α, will be removed in ꞵ
        channelGroup = ChannelGroup::eChannel_Listens;
        break;

    case eChlid_UI_Alarm    :
    case eChlid_UI_Sync     :
    case eChlid_UI_TD       :
  //case eChlid_UI_DD       : // has duplicate value as eChlid_UI_Sync
        channelGroup = ChannelGroup::eChannel_Outputs;
        break;

    default:
        ok = false;
        break;

    }
    if (vOK) *vOK = ok;
    if (vDebugChanngel) *vDebugChanngel = debugChannel;

    return channelGroup;
}

/*!
 * \brief   FrameInterface::onFrameReceive
 * \details This the slot connected to the CanInterface didFrameReceive signal.
 *          When a frame received over the CANBus,
 *          this slot will be called to check the channel if should be listened to.
 *          and will emit didFrameReceive if should be handled and ignored otherwise.
 * \param   vFrame - The frame has to be sent
 */
void FrameInterface::onFrameReceive(const QCanBusFrame &vFrame)
{
    bool ok = false;
    bool debugChannel = false;

    quint32 mFrameId = vFrame.frameId();

    ChannelGroup channelGroup = checkChannel(mFrameId, &ok, &debugChannel);

    QString logMessage;
    if ( debugChannel ) {
        logMessage = "Debug Channel\r\n" +
                Format::toHexString(mFrameId, false, eLenChannelDigits) + " -- " + vFrame.payload().toHex(' ');
        LOG_DEBUG(logMessage);
    }
    if ( ! ok         ) {
        logMessage = "Unexpected Channel\r\n" +
                Format::toHexString(mFrameId, false, eLenChannelDigits) + " -- " + vFrame.payload().toHex(' ');
        LOG_DEBUG(logMessage);
        return;
    }

    if ( channelGroup != ChannelGroup::eChannel_Listens) {
        return;
    }

    Can_Id mCan_Id = static_cast<Can_Id>(mFrameId);
    emit didFrameReceive(mCan_Id, vFrame.payload());
}

/*!
 * \brief   FrameInterface::onFrameTransmit
 * \details This the slot connected to the MessageDispatcher didFrameTransmit signal.
 *          When a frame needs to be send to CANBus,
 *          this slot will call transmitFrame method to do the job.
 * \param   vCan_Id - CANBus Can Id target of the frame.
 * \param   vData   - The data which this frame will carry.
 */
void FrameInterface::onFrameTransmit(Can_Id vCan_Id, const QByteArray &vData)
{
    appendHead(vCan_Id, vData);
    // DEBUG: qDebug() << _timestamp << "apnd #" << _txFrameList.count();
}

/*!
 * \brief FrameInterface::onFrameWritten
 * \param vCount
 */
void FrameInterface::onFrameWritten(qint64 /*vCount*/)
{
    _transmitted = true;
    removeHead();
    // DEBUG: qDebug() << _timestamp << "Sent #" << _txFrameList.count() << vCount;
}

/*!
 * \brief   FrameInterface::timerEvent
 * \details This event handler is re-implemented in this subclass to receive timer events for this object.
 */
void FrameInterface::timerEvent(QTimerEvent *)
{
     static quint8 count = 0;
     // TEST : _timestamp = QTime::currentTime().toString("HH:mm:ss.zzz");

     if (++count != _interval) return;
     // DEBUG: qDebug() << _timestamp;
     count = 0;
     _transmitted = false;
     trnsmtHead();
}

/*!
 * \brief   FrameInterface::trnsmtHead
 * \details Transmits the head of the transmit buffer
 *          Sends an empty frame with lowest priority if the transmit buffer is empty
 *          to keep the UI board Can-driver awake.
 */
void FrameInterface::trnsmtHead()
{
    if ( _txFrameList.isEmpty() ) {
        if ( gSendEmptyKeepAwake ) {
            transmitFrame(eChlid_LOWEST,QByteArray()); // Keep the CANBus awake.
            return;
        }
    }
    else {
        Frame frame = _txFrameList.first();
        transmitFrame(frame.can_Id, frame.data);
        // DEBUG: qDebug() << _timestamp << "Tsmt #" << _txFrameList.count();
    }
}

/*!
 * \brief   FrameInterface::removeHead
 * \details Removes the frame from the head of the transmit buffer
 *          in case transmission has been confirmed by the CANBus driver
 *          in the FrameInterface::onFrameWritten slot
 *          which is connected to CanInterface::didFrameWritten.
 */
void FrameInterface::removeHead()
{
    if ( _txFrameList.isEmpty() ) {
        return;
    }
    _txFrameList.removeFirst();
}

/*!
 * \brief   FrameInterface::appendHead
 * \details Appends the frame to the transmit buffer to be sent later
 * \param   vCan_Id - the CANBus id
 * \param   vData   - the data to be sent
 */
void FrameInterface::appendHead(Can_Id vCan_Id, const QByteArray &vData)
{
    //DEBUG qDebug() << "F " << _txFrameList.count();
    if (_txFrameList.count() >= _txFrameList_Max) {
        static quint32 i = 0;
        if ( i % 60 == 0 ) { // log only for the first time and each minute.
            LOG_DEBUG(QString("Transmit buffer overflow of %1").arg(_txFrameList_Max));
        }
        if ( i < UINT32_MAX - 1 )   i++  ;
        else                        i = 0;
        return;
    }

    Frame frame = Frame(vCan_Id, vData);
    _txFrameList.append(frame);
}