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#include "qmouselinuxtp_qws.h"

#ifndef QT_NO_QWS_MOUSE_LINUXTP
#include "qwindowsystem_qws.h"
#include "qsocketnotifier.h"
#include "qtimer.h"
#include "qapplication.h"
#include "qscreen_qws.h"
#include <private/qcore_unix_p.h> // overrides QT_OPEN

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <termios.h>

QT_BEGIN_NAMESPACE

#if defined(QT_QWS_IPAQ)
 #define QT_QWS_IPAQ_RAW
 #define QT_QWS_SCREEN_COORDINATES
 typedef struct {
        unsigned short pressure;
        unsigned short x;
        unsigned short y;
        unsigned short pad;
 } TS_EVENT;
#elif defined(QT_QWS_EBX)
 #define QT_QWS_EBX_RAW
 #define QT_QWS_SCREEN_COORDINATES
#ifndef QT_QWS_SHARP
  typedef struct {
        unsigned short pressure;
        unsigned short x;
        unsigned short y;
        unsigned short pad;
  } TS_EVENT;
 #else
  typedef struct {
       long y;
       long x;
       long pressure;
       long long millisecs;
  } TS_EVENT;
  #define QT_QWS_TP_SAMPLE_SIZE 10
  #define QT_QWS_TP_MINIMUM_SAMPLES 4
  #define QT_QWS_TP_PRESSURE_THRESHOLD 500
  #define QT_QWS_TP_MOVE_LIMIT 50
  #define QT_QWS_TP_JITTER_LIMIT 2
 #endif
#else // not IPAQ, not SHARP
  typedef struct {
    unsigned short pressure;
    unsigned short x;
    unsigned short y;
    unsigned short pad;
  } TS_EVENT;
#endif

#ifndef QT_QWS_TP_SAMPLE_SIZE
#define QT_QWS_TP_SAMPLE_SIZE 5
#endif

#ifndef QT_QWS_TP_MINIMUM_SAMPLES
#define QT_QWS_TP_MINIMUM_SAMPLES 5
#endif

#ifndef QT_QWS_TP_PRESSURE_THRESHOLD
#define QT_QWS_TP_PRESSURE_THRESHOLD 1
#endif

#ifndef QT_QWS_TP_MOVE_LIMIT
#define QT_QWS_TP_MOVE_LIMIT 100
#endif

#ifndef QT_QWS_TP_JITTER_LIMIT
#define QT_QWS_TP_JITTER_LIMIT 2
#endif

class QWSLinuxTPMouseHandlerPrivate : public QObject
{
    Q_OBJECT
public:
    QWSLinuxTPMouseHandlerPrivate(QWSLinuxTPMouseHandler *h, const QString &);
    ~QWSLinuxTPMouseHandlerPrivate();

    void suspend();
    void resume();
private:
    static const int mouseBufSize = 2048;
    int mouseFD;
    QPoint oldmouse;
    QPoint oldTotalMousePos;
    bool waspressed;
    QPolygon samples;
    int currSample;
    int lastSample;
    int numSamples;
    int skipCount;
    int mouseIdx;
    uchar mouseBuf[mouseBufSize];
    QWSLinuxTPMouseHandler *handler;
    QSocketNotifier *mouseNotifier;

private slots:
    void readMouseData();
};

QWSLinuxTPMouseHandler::QWSLinuxTPMouseHandler(const QString &driver, const QString &device)
    : QWSCalibratedMouseHandler(driver, device)
{
    d = new QWSLinuxTPMouseHandlerPrivate(this, device);
}

QWSLinuxTPMouseHandler::~QWSLinuxTPMouseHandler()
{
    delete d;
}

void QWSLinuxTPMouseHandler::suspend()
{
    d->suspend();
}

void QWSLinuxTPMouseHandler::resume()
{
    d->resume();
}

QWSLinuxTPMouseHandlerPrivate::QWSLinuxTPMouseHandlerPrivate(QWSLinuxTPMouseHandler *h,
        const QString &device)
    : samples(QT_QWS_TP_SAMPLE_SIZE), currSample(0), lastSample(0),
    numSamples(0), skipCount(0), handler(h)
{
    QString mousedev;
    if (device.isEmpty()) {
#if defined(QT_QWS_IPAQ)
# ifdef QT_QWS_IPAQ_RAW
        mousedev = QLatin1String("/dev/h3600_tsraw");
# else
        mousedev = QLatin1String("/dev/h3600_ts");
# endif
#else
        mousedev = QLatin1String("/dev/ts");
#endif
    } else {
        mousedev = device;
    }
    if ((mouseFD = QT_OPEN(mousedev.toLatin1().constData(), O_RDONLY | O_NDELAY)) < 0) {
        qWarning("Cannot open %s (%s)", qPrintable(mousedev), strerror(errno));
        return;
    }

    mouseNotifier = new QSocketNotifier(mouseFD, QSocketNotifier::Read,
                                         this);
    connect(mouseNotifier, SIGNAL(activated(int)),this, SLOT(readMouseData()));
    waspressed=false;
    mouseIdx = 0;
}

QWSLinuxTPMouseHandlerPrivate::~QWSLinuxTPMouseHandlerPrivate()
{
    if (mouseFD >= 0)
        QT_CLOSE(mouseFD);
}

void QWSLinuxTPMouseHandlerPrivate::suspend()
{
    if (mouseNotifier)
        mouseNotifier->setEnabled(false);
}

void QWSLinuxTPMouseHandlerPrivate::resume()
{
    mouseIdx=0;
    currSample=0;
    lastSample=0;
    numSamples=0;
    skipCount=0;
    if (mouseNotifier)
        mouseNotifier->setEnabled(true);
}


void QWSLinuxTPMouseHandlerPrivate::readMouseData()
{
    if(!qt_screen)
        return;

    int n;
    do {
        n = QT_READ(mouseFD, mouseBuf+mouseIdx, mouseBufSize-mouseIdx);
        if (n > 0)
            mouseIdx += n;
    } while (n > 0 && mouseIdx < mouseBufSize);

    //qDebug("readMouseData()");

    TS_EVENT *data;
    int idx = 0;

    // perhaps we shouldn't be reading EVERY SAMPLE.
    while (mouseIdx-idx >= (int)sizeof(TS_EVENT)) {
        uchar *mb = mouseBuf+idx;
        data = (TS_EVENT *) mb;

        if(data->pressure >= QT_QWS_TP_PRESSURE_THRESHOLD) {
#ifdef QT_QWS_SHARP
            samples[currSample] = QPoint(1000 - data->x, data->y);
#else
            samples[currSample] = QPoint(data->x, data->y);
#endif
            numSamples++;
            if (numSamples >= QT_QWS_TP_MINIMUM_SAMPLES) {
                int sampleCount = qMin(numSamples + 1,samples.count());

                // average the rest
                QPoint mousePos = QPoint(0, 0);
                QPoint totalMousePos = oldTotalMousePos;
                totalMousePos += samples[currSample];
                if(numSamples >= samples.count())
                    totalMousePos -= samples[lastSample];

                mousePos = totalMousePos / (sampleCount - 1);
#if defined(QT_QWS_SCREEN_COORDINATES)
                mousePos = handler->transform(mousePos);
#endif
                if(!waspressed)
                    oldmouse = mousePos;
                QPoint dp = mousePos - oldmouse;
                int dxSqr = dp.x() * dp.x();
                int dySqr = dp.y() * dp.y();
                if (dxSqr + dySqr < (QT_QWS_TP_MOVE_LIMIT * QT_QWS_TP_MOVE_LIMIT)) {
                    if (waspressed) {
                        if ((dxSqr + dySqr > (QT_QWS_TP_JITTER_LIMIT * QT_QWS_TP_JITTER_LIMIT)) || skipCount > 2) {
                            handler->mouseChanged(mousePos,Qt::LeftButton);
                            oldmouse = mousePos;
                            skipCount = 0;
                        } else {
                            skipCount++;
                        }
                    } else {
                        handler->mouseChanged(mousePos,Qt::LeftButton);
                        oldmouse=mousePos;
                        waspressed=true;
                    }

                    // save recuring information
                    currSample++;
                    if (numSamples >= samples.count())
                        lastSample++;
                    oldTotalMousePos = totalMousePos;
                } else {
                    numSamples--; // don't use this sample, it was bad.
                }
            } else {
                // build up the average
                oldTotalMousePos += samples[currSample];
                currSample++;
            }
            if (currSample >= samples.count())
                currSample = 0;
            if (lastSample >= samples.count())
                lastSample = 0;
        } else {
            currSample = 0;
            lastSample = 0;
            numSamples = 0;
            skipCount = 0;
            oldTotalMousePos = QPoint(0,0);
            if (waspressed) {
                handler->mouseChanged(oldmouse,0);
                oldmouse = QPoint(-100, -100);
                waspressed=false;
            }
        }
        idx += sizeof(TS_EVENT);
    }

    int surplus = mouseIdx - idx;
    for (int i = 0; i < surplus; i++)
        mouseBuf[i] = mouseBuf[idx+i];
    mouseIdx = surplus;
}

QT_END_NAMESPACE

#include "qmouselinuxtp_qws.moc"

#endif //QT_NO_QWS_MOUSE_LINUXTP
