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#include <QMetaType>

#include "qgeoinfothread_wince_p.h"

Q_DECLARE_METATYPE(GPS_POSITION);

QTM_BEGIN_NAMESPACE

// ========== QGeoInfoValidator ==========

QGeoInfoValidator::QGeoInfoValidator() {}

QGeoInfoValidator::~QGeoInfoValidator() {}

// ========== QGeoInfoThreadWinCE ==========

// This QGeoInfoThreadWinCE instance takes ownership of the validator, and must delete it before

// it is destructed.

QGeoInfoThreadWinCE::QGeoInfoThreadWinCE(QGeoInfoValidator *validator, bool timeoutsForPeriodicUpdates, QObject *parent)

        : QThread(parent),

        validator(validator),

        timeoutsForPeriodicUpdates(timeoutsForPeriodicUpdates),

        requestScheduled(false),

        requestInterval(0),

        updatesScheduled(false),

        updatesInterval(0),

        stopping(false),

        hasLastPosition(false),

        invalidDataReceived(false),

        updateTimeoutTriggered(false)

{

    qRegisterMetaType<GPS_POSITION>();

    m_newDataEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

    m_gpsStateChange = CreateEvent(NULL, FALSE, FALSE, NULL);

    m_wakeUpEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

}

QGeoInfoThreadWinCE::~QGeoInfoThreadWinCE()

{

    // Let/make the thread finish...

    mutex.lock();

    updatesScheduled = false;

    requestScheduled = false;

    stopping = true;

    mutex.unlock();

    wakeUp();

    wait();

    // ...then clean up.

    delete validator;

    CloseHandle(m_newDataEvent);

    CloseHandle(m_gpsStateChange);

    CloseHandle(m_wakeUpEvent);

}

// TODO - just need to add the WinCE line from QTime::currentTime to QDateTime::currentDateTime

// and we can scrap this method

QDateTime QGeoInfoThreadWinCE::currentDateTime()

{

    QDate d = QDate::currentDate();

    QTime t = QTime::currentTime();

    // just in case we past midnight in between the last two calls

    if (d != QDate::currentDate()) {

        d = QDate::currentDate();

        t = QTime::currentTime();

    }

    return QDateTime(d, t);

}

int QGeoInfoThreadWinCE::msecsTo(QDateTime from, QDateTime to)

{

    int MSECS_PER_DAY = 86400000;

    return (from.date().daysTo(to.date()) * MSECS_PER_DAY) + from.time().msecsTo(to.time());

}

void QGeoInfoThreadWinCE::requestUpdate(int timeout)

{

    QMutexLocker locker(&mutex);

    if (!requestScheduled) {

        requestScheduled = true;

        if (timeout == 0)

            timeout = DefaultRequestTimeout;

        requestInterval = timeout;

        requestNextTime = currentDateTime().addMSecs(requestInterval);

        locker.unlock();

        wakeUp();

    }

}

void QGeoInfoThreadWinCE::startUpdates()

{

    QMutexLocker locker(&mutex);

    if (!updatesScheduled) {

        updatesScheduled = true;

        updateTimeoutTriggered = false;

        hasLastPosition = false;

        if (updatesInterval != 0)

            updatesNextTime = currentDateTime().addMSecs(updatesInterval);

        locker.unlock();

        wakeUp();

    }

}

void QGeoInfoThreadWinCE::stopUpdates()

{

    QMutexLocker locker(&mutex);

    if (updatesScheduled) {

        updatesScheduled = false;

        locker.unlock();

        wakeUp();

    }

}

void QGeoInfoThreadWinCE::setUpdateInterval(int interval)

{

    QMutexLocker locker(&mutex);

    if (interval == updatesInterval)

        return;

    int oldInterval = updatesInterval;

    updatesInterval = interval;

    if (updatesScheduled) {

        QDateTime now = currentDateTime();

        // The periodic update interval has been changed and updates are still ocurring.

        if (oldInterval != 0) {

            if (updatesInterval != 0) {

                // If we are changing fixed intervals we update the scheduled time for the next

                // periodic update, making sure that it is scheduled in the future.

                updatesNextTime = updatesNextTime.addMSecs(updatesInterval - oldInterval);

                while (msecsTo(now, updatesNextTime) < 0)

                    updatesNextTime = updatesNextTime.addMSecs(updatesInterval);

            } else {

                // If we now want to emit updates as the data arrives we invalidate the scheduled

                // time for the next update, just to be on the safe side.

                updatesNextTime = now;

            }

        } else {

            // If we were previously emitting updates as the data arrived we set the scheduled time

            // for the next periodic update.

            updatesNextTime = now.addMSecs(updatesInterval);

        }

        locker.unlock();

        wakeUp();

    }

}

void QGeoInfoThreadWinCE::wakeUp()

{

    SetEvent(m_wakeUpEvent);

    statusUpdated.wakeAll();

}

// We try to keep the GPS turned off as much as we can to preserve battery life.

// When run() is called we turn on the GPS device and we leave it on

// until the request is satisfied or periodic updates are stopped.

// The methods requestUpdate() and startUpdates() will call start() if required.

void QGeoInfoThreadWinCE::run()

{

    mutex.lock();

    gpsReachedOnState = false;

    m_gps = NULL;

    const int handleCount = 3;

    HANDLE handles[handleCount] = { m_newDataEvent, m_gpsStateChange, m_wakeUpEvent };

    if (updatesScheduled || requestScheduled) {

        m_gps = GPSOpenDevice(m_newDataEvent, m_gpsStateChange, NULL, 0);

    }

    while (true) {

        if (stopping)

            break;

        if (!updatesScheduled && !requestScheduled) {

            if (m_gps != NULL) {

                GPSCloseDevice(m_gps);

                m_gps = NULL;

            }

            statusUpdated.wait(&mutex);

            if (updatesScheduled || requestScheduled) {

                gpsReachedOnState = false;

                m_gps = GPSOpenDevice(m_newDataEvent, m_gpsStateChange, NULL, 0);

            }

        }

        // If the periodic update is 0 then updates are returned as available.

        // If this is not the case then the next timeout will be set for whichever of

        // the request and periodic updates that is due next.

        // We cap the amount of time we spend waiting for updates.

        DWORD timeout = MaximumMainLoopWaitTime;

        QDateTime now = currentDateTime();

        if (requestScheduled) {

            if (!updatesScheduled || (updatesInterval == 0)

                    || (msecsTo(requestNextTime, updatesNextTime) >= 0)) {

                timeout = msecsTo(now, requestNextTime) + 100;

            } else {

                if (updatesInterval != 0)

                    timeout = msecsTo(now, updatesNextTime) + 100;

            }

        } else {

            // updatesScheduled has to be true or we wouldn't still be in the larger while loop.

            if (updatesInterval != 0)

                timeout = msecsTo(now, updatesNextTime) + 100;

        }

        if (timeout > MaximumMainLoopWaitTime)

            timeout = MaximumMainLoopWaitTime;

        mutex.unlock();

        DWORD dwRet = WaitForMultipleObjects(handleCount, handles, FALSE, timeout);

        mutex.lock();

        // The GPS data has been updated.

        if (dwRet == WAIT_OBJECT_0) {

            // The other options are:

            // dwRet == WAIT_OBJECT_0 + 1

            //   => The GPS state has been updated.

            // dwRet == WAIT_OBJECT_0 + 2

            //   => We called QGeoInfoThreadWinCE::wakeUp().

            // dwRet == WAIT_TIMEOUT

            //   => WaitForMultipleObjects() timed out.

            GPS_POSITION posn;

            posn.dwVersion = GPS_VERSION_1;

            posn.dwSize = sizeof(posn);

            dwRet = GPSGetPosition(m_gps, &posn, timeout, 0);

            if (dwRet == ERROR_SUCCESS) {

                if (!validator->valid(posn)) {

                    invalidDataReceived = true;

                } else {

                    m_lastPosition = posn;

                    hasLastPosition = true;

                    updateTimeoutTriggered = false;

                    // A request and a periodic update could both be satisfied at once.

                    // We use this flag to prevent a double update.

                    bool emitDataUpdated = false;

                    // If a request is in process we emit the dataUpdated signal.

                    if (requestScheduled) {

                        emitDataUpdated = true;

                        requestScheduled = false;

                    }

                    // If we are updating as data becomes available or if the update period has elapsed

                    // we emit the dataUpdated signal.

                    if (updatesScheduled) {

                        QDateTime now = currentDateTime();

                        if (updatesInterval == 0) {

                            emitDataUpdated = true;

                        } else if (msecsTo(now, updatesNextTime) < 0) {

                            while (msecsTo(now, updatesNextTime) < 0)

                                updatesNextTime = updatesNextTime.addMSecs(updatesInterval);

                            emitDataUpdated = true;

                        }

                    }

                    if (emitDataUpdated) {

                        hasLastPosition = false;

                        mutex.unlock();

                        emit dataUpdated(m_lastPosition);

                        mutex.lock();

                    }

                }

            }

        }

        if (dwRet != WAIT_OBJECT_0 || invalidDataReceived) {

            invalidDataReceived = false;

            // Third party apps may have the ability to turn off the gps hardware independently of

            // the Microsoft GPS API.

            // This checks for an unexpected power down and turns the hardware back on.

            // The GPS state has been updated.

            if (dwRet == WAIT_OBJECT_0 + 1) {

                GPS_DEVICE device;

                device.dwVersion = GPS_VERSION_1;

                device.dwSize = sizeof(device);

                dwRet = GPSGetDeviceState(&device);

                if (device.dwDeviceState == SERVICE_STATE_ON) {

                    gpsReachedOnState = true;

                } else if ((device.dwDeviceState == SERVICE_STATE_OFF) && gpsReachedOnState) {

                    // We do not want to mess with devices that are slow starting up, so we only

                    // turn on devices that have previously reached the "On" state.

                    gpsReachedOnState = false;

                    m_gps = GPSOpenDevice(m_newDataEvent, m_gpsStateChange, NULL, 0);

                }

            }

            // We reach this point if the gps state has changed, if the wake up event has been

            // triggered, if we received data we were not interested in from the GPS,

            // or if a timeout occurred while waiting for gps data.

            //

            // In all of these cases we should check for request and periodic update timeouts.

            QDateTime now = currentDateTime();

            bool emitUpdateTimeout = false;

            // Check for request timeouts.

            if (requestScheduled && msecsTo(now, requestNextTime) < 0) {

                requestScheduled = false;

                emitUpdateTimeout = true;

            }

            // Check to see if a periodic update is due.

            if (updatesScheduled && updatesInterval != 0 && (msecsTo(now, updatesNextTime) < 0)) {

                while (msecsTo(now, updatesNextTime) < 0)

                    updatesNextTime = updatesNextTime.addMSecs(updatesInterval);

                if (hasLastPosition) {

                    hasLastPosition = false;

                    mutex.unlock();

                    emit dataUpdated(m_lastPosition);

                    mutex.lock();

                } else {

                    if (timeoutsForPeriodicUpdates && !updateTimeoutTriggered) {

                        updateTimeoutTriggered = true;

                        emitUpdateTimeout = true;

                    }

                }

            }

            if (emitUpdateTimeout) {

                mutex.unlock();

                emit updateTimeout();

                mutex.lock();

            }

        }

    }

    if (m_gps != NULL)

        GPSCloseDevice(m_gps);

    mutex.unlock();

}

#include "moc_qgeoinfothread_wince_p.cpp"

QTM_END_NAMESPACE