/*
 * Copyright (C) 2012. Rayman Zhang <raymanzhang@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package cn.mdict;

import android.app.Activity;
import android.view.GestureDetector;
import android.view.MotionEvent;

/**
 * User: Rayman
 * Date: 11-12-20
 * Time: 下午2:33
 */
public class SimpleGestureFilter extends GestureDetector.SimpleOnGestureListener {

    public final static int SWIPE_UP = 1;
    public final static int SWIPE_DOWN = 2;
    public final static int SWIPE_LEFT = 3;
    public final static int SWIPE_RIGHT = 4;

    public final static int MODE_TRANSPARENT = 0;
    public final static int MODE_SOLID = 1;
    public final static int MODE_DYNAMIC = 2;

    private final static int ACTION_FAKE = -13; //just an unlikely number
    private int swipe_Min_Distance = 100;
    private int swipe_Max_Distance = 350;
    private int swipe_Min_Velocity = 100;

    private int mode = MODE_DYNAMIC;
    private boolean running = true;
    private boolean tapIndicator = false;

    private Activity context;
    private GestureDetector detector;
    private SimpleGestureListener listener;


    public SimpleGestureFilter(Activity context, SimpleGestureListener sgl) {

        this.context = context;
        this.detector = new GestureDetector(context, this);
        this.listener = sgl;
    }

    public void onTouchEvent(MotionEvent event) {

        if (!this.running)
            return;

        boolean result = this.detector.onTouchEvent(event);

        if (this.mode == MODE_SOLID)
            event.setAction(MotionEvent.ACTION_CANCEL);
        else if (this.mode == MODE_DYNAMIC) {

            if (event.getAction() == ACTION_FAKE)
                event.setAction(MotionEvent.ACTION_UP);
            else if (result)
                event.setAction(MotionEvent.ACTION_CANCEL);
            else if (this.tapIndicator) {
                event.setAction(MotionEvent.ACTION_DOWN);
                this.tapIndicator = false;
            }

        }
        //else just do nothing, it's Transparent
    }

    public void setMode(int m) {
        this.mode = m;
    }

    public int getMode() {
        return this.mode;
    }

    public void setEnabled(boolean status) {
        this.running = status;
    }

    public void setSwipeMaxDistance(int distance) {
        this.swipe_Max_Distance = distance;
    }

    public void setSwipeMinDistance(int distance) {
        this.swipe_Min_Distance = distance;
    }

    public void setSwipeMinVelocity(int distance) {
        this.swipe_Min_Velocity = distance;
    }

    public int getSwipeMaxDistance() {
        return this.swipe_Max_Distance;
    }

    public int getSwipeMinDistance() {
        return this.swipe_Min_Distance;
    }

    public int getSwipeMinVelocity() {
        return this.swipe_Min_Velocity;
    }


    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
                           float velocityY) {

        final float xDistance = Math.abs(e1.getX() - e2.getX());
        final float yDistance = Math.abs(e1.getY() - e2.getY());

        if (xDistance > this.swipe_Max_Distance || yDistance > this.swipe_Max_Distance)
            return false;

        velocityX = Math.abs(velocityX);
        velocityY = Math.abs(velocityY);
        boolean result = false;

        if (velocityX > this.swipe_Min_Velocity && xDistance > this.swipe_Min_Distance) {
            if (e1.getX() > e2.getX()) // right to left
                this.listener.onSwipe(SWIPE_LEFT);
            else
                this.listener.onSwipe(SWIPE_RIGHT);

            result = true;
        } else if (velocityY > this.swipe_Min_Velocity && yDistance > this.swipe_Min_Distance) {
            if (e1.getY() > e2.getY()) // bottom to up
                this.listener.onSwipe(SWIPE_UP);
            else
                this.listener.onSwipe(SWIPE_DOWN);

            result = true;
        }

        return result;
    }

    @Override
    public boolean onSingleTapUp(MotionEvent e) {
        this.tapIndicator = true;
        return false;
    }

    @Override
    public boolean onDoubleTap(MotionEvent arg0) {
        this.listener.onDoubleTap();
        return true;
    }

    @Override
    public boolean onDoubleTapEvent(MotionEvent arg0) {
        return true;
    }

    @Override
    public boolean onSingleTapConfirmed(MotionEvent arg0) {

        if (this.mode == MODE_DYNAMIC) {        // we owe an ACTION_UP, so we fake an
            arg0.setAction(ACTION_FAKE);      //action which will be converted to an ACTION_UP later.

            this.context.dispatchTouchEvent(arg0);
        }

        return false;
    }


    static interface SimpleGestureListener {
        void onSwipe(int direction);

        void onDoubleTap();
    }

}