content: /*
   * Copyright (C) 2015 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.launcher3.dragndrop;
  
  import android.content.Context;
  import android.view.DragEvent;
  import android.view.MotionEvent;
  import com.android.launcher3.DropTarget.DragObject;
  import com.android.launcher3.Utilities;
  
  /**
   * Base class for driving a drag/drop operation.
   */
  public abstract class DragDriver {
      protected final EventListener mEventListener;
  
      public interface EventListener {
          void onDriverDragMove(float x, float y);
          void onDriverDragExitWindow();
          void onDriverDragEnd(float x, float y);
          void onDriverDragCancel();
      }
  
      public DragDriver(EventListener eventListener) {
          mEventListener = eventListener;
      }
  
      /**
       * Handles ending of the DragView animation.
       */
      public void onDragViewAnimationEnd() { }
  
      public boolean onTouchEvent(MotionEvent ev) {
          final int action = ev.getAction();
  
          switch (action) {
              case MotionEvent.ACTION_MOVE:
                  mEventListener.onDriverDragMove(ev.getX(), ev.getY());
                  break;
              case MotionEvent.ACTION_UP:
                  mEventListener.onDriverDragMove(ev.getX(), ev.getY());
                  mEventListener.onDriverDragEnd(ev.getX(), ev.getY());
                  break;
              case MotionEvent.ACTION_CANCEL:
                  mEventListener.onDriverDragCancel();
                  break;
          }
  
          return true;
      }
  
      public abstract boolean onDragEvent (DragEvent event);
  
  
      public boolean onInterceptTouchEvent(MotionEvent ev) {
          final int action = ev.getAction();
  
          switch (action) {
              case MotionEvent.ACTION_UP:
                  mEventListener.onDriverDragEnd(ev.getX(), ev.getY());
                  break;
              case MotionEvent.ACTION_CANCEL:
                  mEventListener.onDriverDragCancel();
                  break;
          }
  
          return true;
      }
  
      public static DragDriver create(Context context, DragController dragController,
              DragObject dragObject, DragOptions options) {
          if (Utilities.ATLEAST_NOUGAT && options.systemDndStartPoint != null) {
              return new SystemDragDriver(dragController, context, dragObject);
          } else {
              return new InternalDragDriver(dragController);
          }
      }
  }
  
  /**
   * Class for driving a system (i.e. framework) drag/drop operation.
   */
  class SystemDragDriver extends DragDriver {
  
      float mLastX = 0;
      float mLastY = 0;
  
      SystemDragDriver(DragController dragController, Context context, DragObject dragObject) {
          super(dragController);
      }
  
      @Override
      public boolean onTouchEvent(MotionEvent ev) {
          return false;
      }
  
      @Override
      public boolean onInterceptTouchEvent(MotionEvent ev) {
          return false;
      }
  
      @Override
      public boolean onDragEvent (DragEvent event) {
          final int action = event.getAction();
  
          switch (action) {
              case DragEvent.ACTION_DRAG_STARTED:
                  mLastX = event.getX();
                  mLastY = event.getY();
                  return true;
  
              case DragEvent.ACTION_DRAG_ENTERED:
                  return true;
  
              case DragEvent.ACTION_DRAG_LOCATION:
                  mLastX = event.getX();
                  mLastY = event.getY();
                  mEventListener.onDriverDragMove(event.getX(), event.getY());
                  return true;
  
              case DragEvent.ACTION_DROP:
                  mLastX = event.getX();
                  mLastY = event.getY();
                  mEventListener.onDriverDragMove(event.getX(), event.getY());
                  mEventListener.onDriverDragEnd(mLastX, mLastY);
                  return true;
              case DragEvent.ACTION_DRAG_EXITED:
                  mEventListener.onDriverDragExitWindow();
                  return true;
  
              case DragEvent.ACTION_DRAG_ENDED:
                  mEventListener.onDriverDragCancel();
                  return true;
  
              default:
                  return false;
          }
      }
  }
  
  /**
   * Class for driving an internal (i.e. not using framework) drag/drop operation.
   */
  class InternalDragDriver extends DragDriver {
      InternalDragDriver(DragController dragController) {
          super(dragController);
      }
  
      @Override
      public boolean onDragEvent (DragEvent event) { return false; }
  }
  