/****************************************************************************

 KHotKeys

 Copyright (C) 1999-2002 Lubos Lunak <l.lunak@kde.org>

 Distributed under the terms of the GNU General Public License version 2.

****************************************************************************/

#ifndef _GESTURES_H_
#define _GESTURES_H_

#include <QTimer>
#include <QMap>
#include <QPointer>
#include <QAbstractNativeEventFilter>
#include <qwindowdefs.h>

#include "windows_handler.h"

namespace KHotKeys {

class Gesture;
class ActionData;

Q_DECL_EXPORT extern QPointer<Gesture> gesture_handler;

/**
 * A PointQuintet represents a point in the gesture,
 * saving not only coordinates but also the relation to the successor.
 * The coordinates x and y are mainly used for drawing the stroke,
 * the rest is used by the gesture matching algoritm.
 */

class PointQuintet
    {
    public:
        // at which percentage of the stroke length does the point occur?
        // 100%=1
        qreal s;
        // relative distance to the successor (s+delta_s is s of the next point)
        qreal delta_s;
        // angle to successor in units of pi
        qreal angle;
        // coordinates scaled to a square box. each goes from 0 to 1
        qreal x, y;
    };

typedef QVector<PointQuintet> StrokePoints;

/**
 * The Stroke saves the raw data of the mouse movement. It gets sent the coordinates and
 * records them while preparing for processing them. The method processData()
 * returns the processed version of this raw data.
 */

class Q_DECL_EXPORT Stroke
    {
    public:
        // largest number of points allowed to be sampled
        enum { MAX_POINTS = 5000 };

        Stroke();
        ~Stroke();
        bool record( int x, int y );

        StrokePoints processData();
        void reset();

    protected:
        // metrics for input stroke
        int min_x, min_y;
        int max_x, max_y;
        int point_count;

        struct point
            {
            int x;
            int y;
            };

        point* points;
    };

/**
 * The Gesture class manages the mouse grabbing and sends its data to a Stroke.
 * Then it emits the Stroke's processed data so that instances of GestureTrigger
 * can handle it.
 */

class Q_DECL_EXPORT Gesture
    : public QObject
    , public QAbstractNativeEventFilter
    {
    Q_OBJECT
    public:
        Gesture( bool enabled_P, QObject* parent_P );
        virtual ~Gesture();
        void enable( bool enable_P );
        void set_mouse_button( unsigned int button_P );
        void set_timeout( int time_P );
        void set_exclude( Windowdef_list* windows_P );
        void register_handler( QObject* receiver_P, const char* slot_P );
        void unregister_handler( QObject* receiver_P, const char* slot_P );

    protected:
        bool nativeEventFilter( const QByteArray & eventType, void * message, long * ) Q_DECL_OVERRIDE;

    private Q_SLOTS:
        void stroke_timeout();
        void active_window_changed( WId window_P );
        void handleScore( ActionData* const data, const qreal score );
    Q_SIGNALS:
        void handle_gesture( const StrokePoints &gesture );
    private:
        void update_grab();
        void grab_mouse( bool grab_P );
        void mouse_replay( bool release_P );
        bool _enabled;
        Stroke stroke;
        int start_x, start_y;
        QTimer nostroke_timer;
        bool recording;
        unsigned int button;
        int timeout;

        // two variables to help determine which action belongs to
        // the best-fitting gesture.
        qreal maxScore;
        ActionData* bestFit;

        Windowdef_list* exclude;
        QMap< QObject*, bool > handlers; // bool is just a dummy
    };



} // namespace KHotKeys

#endif
