/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.dialer.callcomposer.camera.camerafocus;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.FrameLayout;
import java.util.ArrayList;
import java.util.List;

/** Focusing overlay. */
public class RenderOverlay extends FrameLayout {

  /** Render interface. */
  interface Renderer {
    boolean handlesTouch();

    boolean onTouchEvent(MotionEvent evt);

    void setOverlay(RenderOverlay overlay);

    void layout(int left, int top, int right, int bottom);

    void draw(Canvas canvas);
  }

  private RenderView renderView;
  private List<Renderer> clients;

  // reverse list of touch clients
  private List<Renderer> touchClients;
  private int[] position = new int[2];

  public RenderOverlay(Context context, AttributeSet attrs) {
    super(context, attrs);
    renderView = new RenderView(context);
    addView(renderView, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
    clients = new ArrayList<>(10);
    touchClients = new ArrayList<>(10);
    setWillNotDraw(false);

    addRenderer(new PieRenderer(context));
  }

  public PieRenderer getPieRenderer() {
    for (Renderer renderer : clients) {
      if (renderer instanceof PieRenderer) {
        return (PieRenderer) renderer;
      }
    }
    return null;
  }

  public void addRenderer(Renderer renderer) {
    clients.add(renderer);
    renderer.setOverlay(this);
    if (renderer.handlesTouch()) {
      touchClients.add(0, renderer);
    }
    renderer.layout(getLeft(), getTop(), getRight(), getBottom());
  }

  public void addRenderer(int pos, Renderer renderer) {
    clients.add(pos, renderer);
    renderer.setOverlay(this);
    renderer.layout(getLeft(), getTop(), getRight(), getBottom());
  }

  public void remove(Renderer renderer) {
    clients.remove(renderer);
    renderer.setOverlay(null);
  }

  @Override
  public boolean dispatchTouchEvent(MotionEvent m) {
    return false;
  }

  private void adjustPosition() {
    getLocationInWindow(position);
  }

  public void update() {
    renderView.invalidate();
  }

  @SuppressLint("ClickableViewAccessibility")
  private class RenderView extends View {

    public RenderView(Context context) {
      super(context);
      setWillNotDraw(false);
    }

    @Override
    public boolean onTouchEvent(MotionEvent evt) {
      if (touchClients != null) {
        boolean res = false;
        for (Renderer client : touchClients) {
          res |= client.onTouchEvent(evt);
        }
        return res;
      }
      return false;
    }

    @Override
    public void onLayout(boolean changed, int left, int top, int right, int bottom) {
      adjustPosition();
      super.onLayout(changed, left, top, right, bottom);
      if (clients == null) {
        return;
      }
      for (Renderer renderer : clients) {
        renderer.layout(left, top, right, bottom);
      }
    }

    @Override
    public void draw(Canvas canvas) {
      super.draw(canvas);
      if (clients == null) {
        return;
      }
      boolean redraw = false;
      for (Renderer renderer : clients) {
        renderer.draw(canvas);
        redraw = redraw || ((OverlayRenderer) renderer).isVisible();
      }
      if (redraw) {
        invalidate();
      }
    }
  }
}