/*

  This file is part of serialplot.

  serialplot 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.

  serialplot 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 serialplot.  If not, see <http://www.gnu.org/licenses/>.

*/

#include <QtDebug>

#include <QtEndian>

#include "floatswap.h"

#include "framedreader.h"

FramedReader::FramedReader(QIODevice* device, QObject* parent) :

    AbstractReader(device, parent)

{

    paused = false;

    // initial settings

    settingsInvalid = 0;

    _numChannels = _settingsWidget.numOfChannels();

    hasSizeByte = _settingsWidget.frameSize() == 0;

    frameSize = _settingsWidget.frameSize();

    syncWord = _settingsWidget.syncWord();

    checksumEnabled = _settingsWidget.isChecksumEnabled();

    onNumberFormatChanged(_settingsWidget.numberFormat());

    debugModeEnabled = _settingsWidget.isDebugModeEnabled();

    checkSettings();

    // init setting connections

    connect(&_settingsWidget, &FramedReaderSettings::numberFormatChanged,

            this, &FramedReader::onNumberFormatChanged);

    connect(&_settingsWidget, &FramedReaderSettings::numOfChannelsChanged,

            this, &FramedReader::onNumOfChannelsChanged);

    connect(&_settingsWidget, &FramedReaderSettings::syncWordChanged,

            this, &FramedReader::onSyncWordChanged);

}

void FramedReader::checkSettings()

{

    // sync word is invalid (empty or missing a nibble at the end)

    if (!syncWord.size())

    {

        settingsInvalid |= SYNCWORD_INVALID;

    }

    else // sync word is valid

    {

        settingsInvalid &= ~SYNCWORD_INVALID;

    }

    // check if fixed frame size is multiple of a sample set size

    if (!hasSizeByte && frameSize % (_numChannels * sampleSize) != 0)

    {

        settingsInvalid |= FRAMESIZE_INVALID;

    }

    else

    {

        settingsInvalid &= ~FRAMESIZE_INVALID;

    }

    // show an error message

    if (settingsInvalid & SYNCWORD_INVALID)

    {

        _settingsWidget.showMessage("Sync word is invalid!", true);

    }

    else if (settingsInvalid & FRAMESIZE_INVALID)

    {

        QString errorMessage =

            QString("Frame size must be multiple of %1 (#channels * sample size)!")\

            .arg(_numChannels * sampleSize);

        _settingsWidget.showMessage(errorMessage, true);

    }

    else

    {

        _settingsWidget.showMessage("All is well!");

    }

}

void FramedReader::onNumOfChannelsChanged(unsigned value)

{

    _numChannels = value;

    checkSettings();

    reset();

    emit numOfChannelsChanged(value);

}

void FramedReader::onSyncWordChanged(QByteArray word)

{

    syncWord = word;

    checkSettings();

    reset();

}

void FramedReader::onFrameSizeChanged(unsigned value)

{

    if (value == 0)

    {

        hasSizeByte = true;

    }

    else

    {

        hasSizeByte = false;

        frameSize = value;

    }

    checkSettings();

    reset();

}

unsigned FramedReader::readData()

{

    unsigned numBytesRead = 0;

    if (settingsInvalid) return numBytesRead;

    // loop until we run out of bytes or more bytes is required

    unsigned bytesAvailable;

    while ((bytesAvailable = _device->bytesAvailable()))

    {

        if (!gotSync) // read sync word

        {

            char c;

            _device->getChar(&c);

            numBytesRead++;

            if (c == syncWord[sync_i]) // correct sync byte?

            {

                sync_i++;

                if (sync_i == (unsigned) syncWord.length())

                {

                    gotSync = true;

                }

            }