/*
   Android Touch Pointer view

   Copyright 2013 Thincast Technologies GmbH, Author: Martin Fleisz

   This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
   If a copy of the MPL was not distributed with this file, You can obtain one at
   http://mozilla.org/MPL/2.0/.
*/

package com.freerdp.freerdpcore.presentation;

import android.content.Context;
import android.graphics.Matrix;
import android.graphics.RectF;
import android.os.Handler;
import android.os.Looper;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ImageView;

import com.freerdp.freerdpcore.R;
import com.freerdp.freerdpcore.utils.GestureDetector;

public class TouchPointerView extends ImageView
{

	private static final int POINTER_ACTION_CURSOR = 0;
	private static final int POINTER_ACTION_CLOSE = 3;

	// the touch pointer consists of 9 quadrants with the following functionality:
	//
	// -------------
	// | 0 | 1 | 2 |
	// -------------
	// | 3 | 4 | 5 |
	// -------------
	// | 6 | 7 | 8 |
	// -------------
	//
	// 0 ... contains the actual pointer (the tip must be centered in the quadrant)
	// 1 ... is left empty
	// 2, 3, 5, 6, 7, 8 ... function quadrants that issue a callback
	// 4 ... pointer center used for left clicks and to drag the pointer
	private static final int POINTER_ACTION_RCLICK = 2;
	private static final int POINTER_ACTION_LCLICK = 4;
	private static final int POINTER_ACTION_MOVE = 4;
	private static final int POINTER_ACTION_SCROLL = 5;
	private static final int POINTER_ACTION_RESET = 6;
	private static final int POINTER_ACTION_KEYBOARD = 7;
	private static final int POINTER_ACTION_EXTKEYBOARD = 8;
	private static final float SCROLL_DELTA = 10.0f;
	private static final int DEFAULT_TOUCH_POINTER_RESTORE_DELAY = 150;
	private RectF pointerRect;
	private final RectF[] pointerAreaRects = new RectF[9];
	private Matrix translationMatrix;
	private boolean pointerMoving = false;
	private boolean pointerScrolling = false;
	private TouchPointerListener listener = null;
	private final Handler uiHandler = new Handler(Looper.getMainLooper());
	private final Runnable restorePointerImage =
	    () -> setPointerImage(R.drawable.touch_pointer_default);
	// gesture detection
	private GestureDetector gestureDetector;
	public TouchPointerView(Context context)
	{
		super(context);
		initTouchPointer(context);
	}

	public TouchPointerView(Context context, AttributeSet attrs)
	{
		super(context, attrs);
		initTouchPointer(context);
	}

	public TouchPointerView(Context context, AttributeSet attrs, int defStyle)
	{
		super(context, attrs, defStyle);
		initTouchPointer(context);
	}

	private void initTouchPointer(Context context)
	{
		gestureDetector =
		    new GestureDetector(context, new TouchPointerGestureListener(), null, true);
		gestureDetector.setLongPressTimeout(500);
		translationMatrix = new Matrix();
		setScaleType(ScaleType.MATRIX);
		setImageMatrix(translationMatrix);

		// init rects
		final float rectSizeWidth = (float)getDrawable().getIntrinsicWidth() / 3.0f;
		final float rectSizeHeight = (float)getDrawable().getIntrinsicWidth() / 3.0f;
		for (int i = 0; i < 3; i++)
		{
			for (int j = 0; j < 3; j++)
			{
				int left = (int)(j * rectSizeWidth);
				int top = (int)(i * rectSizeHeight);
				int right = left + (int)rectSizeWidth;
				int bottom = top + (int)rectSizeHeight;
				pointerAreaRects[i * 3 + j] = new RectF(left, top, right, bottom);
			}
		}
		pointerRect =
		    new RectF(0, 0, getDrawable().getIntrinsicWidth(), getDrawable().getIntrinsicHeight());
	}

	public void setTouchPointerListener(TouchPointerListener listener)
	{
		this.listener = listener;
	}

	public int getPointerWidth()
	{
		return getDrawable().getIntrinsicWidth();
	}

	public int getPointerHeight()
	{
		return getDrawable().getIntrinsicHeight();
	}

	public float[] getPointerPosition()
	{
		float[] curPos = new float[2];
		translationMatrix.mapPoints(curPos);
		return curPos;
	}

	private void movePointer(float deltaX, float deltaY)
	{
		translationMatrix.postTranslate(deltaX, deltaY);
		setImageMatrix(translationMatrix);
	}

	private void ensureVisibility(int screen_width, int screen_height)
	{
		float[] curPos = new float[2];
		translationMatrix.mapPoints(curPos);

		if (curPos[0] > (screen_width - pointerRect.width()))
			curPos[0] = screen_width - pointerRect.width();
		if (curPos[0] < 0)
			curPos[0] = 0;
		if (curPos[1] > (screen_height - pointerRect.height()))
			curPos[1] = screen_height - pointerRect.height();
		if (curPos[1] < 0)
			curPos[1] = 0;

		translationMatrix.setTranslate(curPos[0], curPos[1]);
		setImageMatrix(translationMatrix);
	}

	private void displayPointerImageAction(int resId)
	{
		setPointerImage(resId);
		uiHandler.removeCallbacks(restorePointerImage);
		uiHandler.postDelayed(restorePointerImage, DEFAULT_TOUCH_POINTER_RESTORE_DELAY);
	}

	private void setPointerImage(int resId)
	{
		setImageResource(resId);
	}

	// returns the pointer area with the current translation matrix applied
	private RectF getCurrentPointerArea(int area)
	{
		RectF transRect = new RectF(pointerAreaRects[area]);
		translationMatrix.mapRect(transRect);
		return transRect;
	}

	private boolean pointerAreaTouched(MotionEvent event, int area)
	{
		RectF transRect = new RectF(pointerAreaRects[area]);
		translationMatrix.mapRect(transRect);
		return transRect.contains(event.getX(), event.getY());
	}

	private boolean pointerTouched(MotionEvent event)
	{
		RectF transRect = new RectF(pointerRect);
		translationMatrix.mapRect(transRect);
		return transRect.contains(event.getX(), event.getY());
	}

	@Override public boolean onTouchEvent(MotionEvent event)
	{
		// check if pointer is being moved or if we are in scroll mode or if the pointer is touched
		if (!pointerMoving && !pointerScrolling && !pointerTouched(event))
			return false;
		return gestureDetector.onTouchEvent(event);
	}

	@Override protected void onLayout(boolean changed, int left, int top, int right, int bottom)
	{
		// ensure touch pointer is visible
		if (changed)
			ensureVisibility(right - left, bottom - top);
	}

	// touch pointer listener - is triggered if an action field is
	public interface TouchPointerListener {
		void onTouchPointerClose();

		void onTouchPointerLeftClick(int x, int y, boolean down);

		void onTouchPointerRightClick(int x, int y, boolean down);

		void onTouchPointerMove(int x, int y);

		void onTouchPointerScroll(boolean down);

		void onTouchPointerToggleKeyboard();

		void onTouchPointerToggleExtKeyboard();

		void onTouchPointerResetScrollZoom();
	}

	private class TouchPointerGestureListener extends GestureDetector.SimpleOnGestureListener
	{

		private MotionEvent prevEvent = null;

		public boolean onDown(MotionEvent e)
		{
			if (pointerAreaTouched(e, POINTER_ACTION_MOVE))
			{
				prevEvent = MotionEvent.obtain(e);
				pointerMoving = true;
			}
			else if (pointerAreaTouched(e, POINTER_ACTION_SCROLL))
			{
				prevEvent = MotionEvent.obtain(e);
				pointerScrolling = true;
				setPointerImage(R.drawable.touch_pointer_scroll);
			}

			return true;
		}

		public boolean onUp(MotionEvent e)
		{
			if (prevEvent != null)
			{
				prevEvent.recycle();
				prevEvent = null;
			}

			if (pointerScrolling)
				setPointerImage(R.drawable.touch_pointer_default);

			pointerMoving = false;
			pointerScrolling = false;
			return true;
		}

		public void onLongPress(MotionEvent e)
		{
			if (pointerAreaTouched(e, POINTER_ACTION_LCLICK))
			{
				setPointerImage(R.drawable.touch_pointer_active);
				pointerMoving = true;
				RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
				listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), true);
			}
		}

		public void onLongPressUp(MotionEvent e)
		{
			if (pointerMoving)
			{
				setPointerImage(R.drawable.touch_pointer_default);
				pointerMoving = false;
				RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
				listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), false);
			}
		}

		public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)
		{
			if (pointerMoving)
			{
				// move pointer graphics
				movePointer((int)(e2.getX() - prevEvent.getX()),
				            (int)(e2.getY() - prevEvent.getY()));
				prevEvent.recycle();
				prevEvent = MotionEvent.obtain(e2);

				// send move notification
				RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
				listener.onTouchPointerMove((int)rect.centerX(), (int)rect.centerY());
				return true;
			}
			else if (pointerScrolling)
			{
				// calc if user scrolled up or down (or if any scrolling happened at all)
				float deltaY = e2.getY() - prevEvent.getY();
				if (deltaY > SCROLL_DELTA)
				{
					listener.onTouchPointerScroll(true);
					prevEvent.recycle();
					prevEvent = MotionEvent.obtain(e2);
				}
				else if (deltaY < -SCROLL_DELTA)
				{
					listener.onTouchPointerScroll(false);
					prevEvent.recycle();
					prevEvent = MotionEvent.obtain(e2);
				}
				return true;
			}
			return false;
		}

		public boolean onSingleTapUp(MotionEvent e)
		{
			// look what area got touched and fire actions accordingly
			if (pointerAreaTouched(e, POINTER_ACTION_CLOSE))
				listener.onTouchPointerClose();
			else if (pointerAreaTouched(e, POINTER_ACTION_LCLICK))
			{
				displayPointerImageAction(R.drawable.touch_pointer_lclick);
				RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
				listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), true);
				listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), false);
			}
			else if (pointerAreaTouched(e, POINTER_ACTION_RCLICK))
			{
				displayPointerImageAction(R.drawable.touch_pointer_rclick);
				RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
				listener.onTouchPointerRightClick((int)rect.centerX(), (int)rect.centerY(), true);
				listener.onTouchPointerRightClick((int)rect.centerX(), (int)rect.centerY(), false);
			}
			else if (pointerAreaTouched(e, POINTER_ACTION_KEYBOARD))
			{
				displayPointerImageAction(R.drawable.touch_pointer_keyboard);
				listener.onTouchPointerToggleKeyboard();
			}
			else if (pointerAreaTouched(e, POINTER_ACTION_EXTKEYBOARD))
			{
				displayPointerImageAction(R.drawable.touch_pointer_extkeyboard);
				listener.onTouchPointerToggleExtKeyboard();
			}
			else if (pointerAreaTouched(e, POINTER_ACTION_RESET))
			{
				displayPointerImageAction(R.drawable.touch_pointer_reset);
				listener.onTouchPointerResetScrollZoom();
			}

			return true;
		}

		public boolean onDoubleTap(MotionEvent e)
		{
			// issue a double click notification if performed in center quadrant
			if (pointerAreaTouched(e, POINTER_ACTION_LCLICK))
			{
				RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
				listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), true);
				listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), false);
			}
			return true;
		}
	}
}
