/*

* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

*

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU Lesser General Public License as published by

* the Free Software Foundation, version 2.1 of the License.

* 

* This program 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 Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser General Public License

* along with this program.  If not, 

* see "http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html/".

*

* Description:

*

*/

#include <qstmuievent_if.h>

#include <qstmfilelogger.h>

#include "qstmzoomgesturerecogniser.h"

#include "qstmgenericsimplegesture.h"

#include "qstmutils.h"

using namespace qstmGesture ;

using namespace qstmUiEventEngine;

QStm_ZoomGestureRecogniser::QStm_ZoomGestureRecogniser(QStm_GestureListenerIf* listener) :

                             QStm_GestureRecogniser(listener), m_area(QRect())

{

    m_rangesizeInPixels = 20 ;  // by default 20 pixels from the edges is the area

    m_zooming = false ;

}

QStm_ZoomGestureRecogniser::~QStm_ZoomGestureRecogniser()

{

}

QStm_GestureRecognitionState QStm_ZoomGestureRecogniser::recognise(int numOfActiveStreams,

                                            QStm_GestureEngineIf* pge)

{

    QStm_GestureRecognitionState state = m_state = ENotMyGesture;

    // Check if we are enabled or not

    if (!m_gestureEnabled) return state ;

    // Look at the events to see if it looks like zoom with one pointer

    if (numOfActiveStreams == 1) {

        const qstmUiEventEngine::QStm_UiEventIf* puie = pge->getUiEvents(0);

        int countOfEvents = puie->countOfEvents();

        qstmUiEventEngine::QStm_UiEventCode eventCode = puie->code();

        if (m_loggingenabled) {

            LOGARG("QStm_ZoomGestureRecogniser: %d num %d code %d", eventCode, countOfEvents, eventCode);

        }

        if (!m_zooming) {

            // We are not yet zoomin, check if we should start, i.e. whether we are

            // inside the zoom trigger areas near the corners when touch is done...

            if (eventCode == qstmUiEventEngine::ETouch) { // It must be ETouch inside the corner

                if (m_loggingenabled)  {

                    LOGARG("QStm_ZoomGestureRecogniser: 0x%x ETouch: num %d code %d, %d", 

                    		this, countOfEvents, puie->currentXY().x(), puie->currentXY().y());

                    LOGARG("QStm_ZoomGestureRecogniser: area, %d,%d %d,%d, range: %d", 

                    		m_area.x(), m_area.y(), m_area.x() + m_area.width(), m_area.y() + m_area.height(), 

                    		m_rangesizeInPixels);

                }

                // the lower left rectangle is m_rangesizeIPixels from the corner

                QRect lowerleft(m_area.x(), m_area.y() + m_area.height() - m_rangesizeInPixels,

                                m_area.x() + m_rangesizeInPixels, m_area.y() + m_area.height()) ;

                QRect upperright(m_area.x() + m_area.width() - m_rangesizeInPixels, m_area.y(),

                                 m_area.x() + m_area.width(), m_area.y() + m_rangesizeInPixels) ;

                m_previoustouch = m_startingtouch = puie->currentXY() ;

                m_delta = 0 ;

                if (lowerleft.contains(m_startingtouch) || upperright.contains(m_startingtouch)) {

                    if (m_loggingenabled) {

                        LOGARG("QStm_ZoomGestureRecogniser: ZOOM IN/OUT, (%d,%d) in %d,%d %d,%d, range: %d",

                            m_startingtouch.x(), m_startingtouch.y(),

                            m_area.x(), m_area.y(), m_area.x() + m_area.width(), m_area.y() + m_area.height(),

                            m_rangesizeInPixels);

                    }

                    m_zooming = true ;

                    if (lowerleft.contains(m_startingtouch)) {

                        m_zoomtype = EZoomIn ;

                    }

                    else {

                        m_zoomtype = EZoomOut ;

                    }

                    state = ELockToThisGesture ;    // keep zooming until release

                    pgest.setLogging(m_loggingenabled) ;

                    pgest.setDetails(&m_delta) ;

                    pgest.setName(m_zoomtype == EZoomIn ? QString("ZoomIn") : QString("ZoomOut")) ;

                    pgest.setType(m_zoomtype);

                    pgest.setTarget(puie->target());

                    // Call the listener to inform that a gesture has happened

                    m_listener->gestureEnter(pgest) ;

                }

                else {

                    // It is not our gesture so do nothing...

                }

            }

            else {

                // It is not touch, so not our initiating UI event.. do nothing

            }

        }

        else {

            // We are already zooming, calculate the changes in zooming factor if it looks we are still zooming

            if (eventCode == qstmUiEventEngine::ERelease) { // ERelease stops zooming

                // We were zooming, but if there are multiple touches we are not any more

            	const qstmUiEventEngine::QStm_UiEventIf* puie = pge->getUiEvents(0);

                m_listener->gestureExit(pgest) ; // should we call this or not?

            }

            else {   // all other UI events will keep on zooming

                state = ELockToThisGesture ;    // Keep the gesture

                const QPoint& p = puie->currentXY() ;

                float newdist = calculateDistance(p) ;

                float olddist = calculateDistance(m_previoustouch) ;

                m_previoustouch = p ;

                m_delta = adjustZoom(olddist, newdist) ;

                state = EGestureActive ;

                // Inform listener only if there is something to say

                if (m_delta != 0) {

                    pgest.setLogging(m_loggingenabled) ;

                    pgest.setDetails(&m_delta) ;

                    pgest.setName(m_zoomtype == EZoomIn ? QString("ZoomIn") : QString("ZoomOut")) ;

                    pgest.setType(m_zoomtype);

                    pgest.setTarget(puie->target());

                    // Call the listener to inform that a gesture has happened

                    m_listener->gestureEnter(pgest) ;

                }

            }

        }

    }

    else {

        if (m_zooming) {

            // We were zooming, but if there are multiple touches we are not any more

        	const qstmUiEventEngine::QStm_UiEventIf* puie = pge->getUiEvents(0);

        	pgest.setTarget(puie->target());

            m_listener->gestureExit(pgest) ; // should we call this or not?

        }

        m_zooming = false ;

    }

    m_state = state;

    return state;

}

void QStm_ZoomGestureRecogniser::release(QStm_GestureEngineIf* pge)

{

    if (m_zooming) {

        m_zooming = false ;

    	const qstmUiEventEngine::QStm_UiEventIf* puie = pge->getUiEvents(0);

    	pgest.setTarget(puie->target());

        m_listener->gestureExit(pgest) ; // should we call this or not?

    }

    if (m_loggingenabled) {

        LOGARG("QStm_ZoomGestureRecogniser: 0x%x release", this);

    }

    m_state = ENotMyGesture;

}

void QStm_ZoomGestureRecogniser::setRange(int rangeInMm)

{

    m_rangesizeInPixels = QStm_Utils::mm2Pixels(rangeInMm) ;

}

void QStm_ZoomGestureRecogniser::setArea(const QRect& theArea)

{

    m_area = theArea ;

    if (m_loggingenabled) {

        LOGARG("QStm_ZoomGestureRecogniser: set area, %d,%d %d,%d", 

        	   m_area.x(), m_area.y(), m_area.x() + m_area.width(), m_area.y() + m_area.height());

    }

}

/*!

 * calculate the distance, return as as float

 */

float QStm_ZoomGestureRecogniser::calculateDistance(const QPoint& tp)

{

	const QPoint p = m_startingtouch;

	return QStm_Utils::distanceF(p, tp);

    /*

	double x = ((m_startingtouch.iX-tp.iX)*(m_startingtouch.iX-tp.iX))+((m_startingtouch.iY-tp.iY)*(m_startingtouch.iY-tp.iY)) ;

    double ddist ;

    Math::Sqrt(ddist, x) ;

    return ddist ;

    */

}

int QStm_ZoomGestureRecogniser::adjustZoom(float& previousDistance, float newDistance)

{

    float diff = newDistance - previousDistance ;

    float logdiff = diff ;

    if (diff < 0) diff = -diff ;

    float changePercentage = (diff/previousDistance)*100.f ;

    if (changePercentage > 10.f)

    {

        // change more than 10%, make at most 10%

        float newdiff = previousDistance*0.1f;

        if (previousDistance > newDistance) newdiff = -newdiff ;

        if (m_loggingenabled) {

            LOGARG("QStm_ZoomGestureRecogniser: adjust zoom from %f to %f : was, now %f %f",

                double(logdiff), double(newdiff), double(previousDistance), double(newDistance));

        }

        previousDistance = previousDistance + newdiff ;

        diff = newdiff ;

    }

    else {

        if (m_loggingenabled)  {

            LOGARG("QStm_ZoomGestureRecogniser: adjust zoom from %f to %f : was, now %f %f",

                double(logdiff), double(diff), double(previousDistance), double(newDistance));

        }

        previousDistance = newDistance ;  // accept the new value and update the new length

        diff = logdiff ;    // put the original back

    }

    return (int)diff ;

}