package org.gcd.test;

import android.app.Activity;
import android.os.Bundle;
import android.view.SurfaceView;
import android.view.SurfaceHolder;
import android.view.MotionEvent;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Color;
import java.util.Hashtable;
import java.util.Set;
import java.util.Iterator;

public class MultiTouch extends Activity {
    private TestView view;
    final int Pitch = 30;

    class TouchPoint {
	public float x;
	public float y;
	public float p;
    }
    Hashtable<Integer, TouchPoint> points;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
	view = new TestView(this);
	points = new Hashtable<Integer, TouchPoint>();
	setContentView(view);
    }

    class TestView extends SurfaceView {
	public TestView(Context context) {
	    super(context);
	}

	@Override
	public void onDraw(Canvas canvas) {
	    canvas.drawColor(Color.WHITE);
	    Paint paint = new Paint();
	    Set keys = points.keySet();
	    for (Iterator i = keys.iterator(); i.hasNext();) {
		Integer id = (Integer)i.next();
		switch (id) {
		case 0:  paint.setColor(Color.RED);   break;
		case 1:  paint.setColor(Color.GREEN); break;
		case 2:  paint.setColor(Color.BLUE);  break;
		default: paint.setColor(Color.BLACK); break;
		}
		paint.setAlpha(128);
		TouchPoint p = points.get(id);
		canvas.drawCircle(p.x, p.y, 10+p.p*200, paint);
	    }
	}

	void put_points(MotionEvent ev) {
	    int count = ev.getPointerCount();
	    for (int i=0; i < count; i++) {
		int id = ev.getPointerId(i);
		TouchPoint p = new TouchPoint();
		p.x = ev.getX(i);
		p.y = ev.getY(i);
		p.p = ev.getPressure(i);
		points.put(id, p);
	    }
	}

	public boolean onTouchEvent(MotionEvent ev) {
	    int action = ev.getAction();
	    switch (action & MotionEvent.ACTION_MASK) {
	    case MotionEvent.ACTION_DOWN:
	    case MotionEvent.ACTION_POINTER_DOWN:
	    case MotionEvent.ACTION_MOVE:
		put_points(ev);
		break;
	    case MotionEvent.ACTION_UP:
		points.remove(ev.getPointerId(0));
		break;
	    case MotionEvent.ACTION_POINTER_UP:
		put_points(ev);
		int index = (action & MotionEvent.ACTION_POINTER_INDEX_MASK)
		    >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;
		points.remove(ev.getPointerId(index));
		break;
	    }
	    Canvas canvas = getHolder().lockCanvas();
	    if (canvas != null) {
		onDraw(canvas);
		getHolder().unlockCanvasAndPost(canvas);
	    }
	    return true;
	}
    }
}