/*

* 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:

*

*/

#ifndef QSTMGESTUREENGINE_H_

#define QSTMGESTUREENGINE_H_

#include "qstmgestureengine_if.h"

#include "qstmuievent_if.h"

#include "qstmgesturedefs.h"

namespace qstmGesture

{

/*!

 * QStm_GestureEngine handles the processing of the UI events.

 * It acts as a stmUiEventEngine::MUiEventObserver to receive the UI events.

 * The gesture recognisers are stored in a list, and at each HandleUiEventL the

 * list of gesture recognisers is processed.  The first one to return EGestureActive

 * from the recognise method "owns" the gesture.  If some other recogniser owned it

 * previously, its release method is called. Gesture recogniser can also lock the gesture

 * by returning ELockToThisGesture. Then only that gesture recogniser will be called

 * until release is detected or the recogniser returns something else than ELockToThisGesture.

 */

class QStm_GestureEngine : public QObject, 

                           public QStm_GestureEngineIf, 

                           public qstmUiEventEngine::QStm_UiEventObserverIf

{

public:

    QStm_GestureEngine();

    virtual ~QStm_GestureEngine();

    /*!

     *  add gesture to the end of the list of gestures

     */

    virtual bool addGesture(const QStm_GestureRecogniserIf* newGesture) ;

    /*!

     * inset a gesture to the specific position

     */

    virtual bool insertGesture(const QStm_GestureRecogniserIf* newGesture, int position = 0);

    virtual int findGesture(const QStm_GestureRecogniserIf* newGesture, int startPos = 0) const;

    virtual int findGestureReverse(const QStm_GestureRecogniserIf* gesture, int startPos) const;

    virtual int findGesture(QStm_GestureUid uid, int startPos = 0) const;

    virtual int findGestureReverse(QStm_GestureUid aUid, int startPos) const;

    virtual int gestureCount() const;

    /*!

     * remove a gesture from the list

     */

    virtual bool removeGesture(const QStm_GestureRecogniserIf* oldGesture) ;

    /*!

     * get the number of non-empty event streams.

     * Event streams correspond UI events generated by one touch pointer (=finger).

     * The low level state machine handles the necessary filtering etc.

     * so that it is safe to remove the event stream after UI Release event has been processed.

     */

    virtual int activeStreamCount() const ;

    /*!

     * get the UI events of stream X

     * \param indexOfActiveStream defines which active stream is used.

     * Note that QStm_UiEventIf contains all the events from down up to the current event.

     * Assumption: the UI events contain the target "window handle", i.e.

     * the gesture recognition needs to be aware of all possible windows of the application.

     */

    virtual const qstmUiEventEngine::QStm_UiEventIf* getUiEvents(int indexOfActiveStream) const ;

    /*!

     * enable/disable logging

     */

    virtual void enableLogging(bool loggingEnabled) {m_loggingEnabled = loggingEnabled;} ;

    /*!

     * The qstmUiEventEngine::QStm_UiEventObserverIf interface

     */

    virtual void handleUiEvent( const qstmUiEventEngine::QStm_UiEventIf& event ) ;

    QStm_GestureRecogniserIf* gestureAt(int idx) { return m_gestures[idx] ; }

private:

    /*!

     * The list of available gesture recognisers

     */

    QList<QStm_GestureRecogniserIf*>  m_gestures;

    /*!

     * Is 5 UI event streams enough?  Jos tulee Torvisen voittaja?

     * We need to store only the latest event since the interface has

     * methods to walk trough the events. The current (sept 2009) 9.2 seems to have dual-touch support

     */

    const qstmUiEventEngine::QStm_UiEventIf* m_uiEventStream[qstmUiEventEngine::KMaxNumberOfPointers] ;

    void storeUiEvent(const qstmUiEventEngine::QStm_UiEventIf& event) ;

    void walkTroughGestures() ;

    void updateUiEvents() ;

    int m_numOfActiveStreams ;

    int m_currentGestureOwner ;

    int m_currentLockedGesture ;

    bool m_loggingEnabled ;

};

}

#endif /* QSTMGESTUREENGINE_H_ */