content: /*
   * Copyright (C) 2018 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.server.wm.utils;
  
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.graphics.Rect;
  import android.view.Surface;
  
  
  /**
   * Utility methods to handle insets represented as rects.
   */
  public class InsetUtils {
  
      private InsetUtils() {
      }
  
      /**
       * Transforms insets given in one rotation into insets in a different rotation.
       *
       * @param inOutInsets the insets to transform, is set to the transformed insets
       * @param rotationDelta the delta between the new and old rotation.
       *                      Must be one of Surface.ROTATION_0/90/180/270.
       */
      public static void rotateInsets(Rect inOutInsets, int rotationDelta) {
          final Rect r = inOutInsets;
          switch (rotationDelta) {
              case Surface.ROTATION_0:
                  return;
              case Surface.ROTATION_90:
                  r.set(r.top, r.right, r.bottom, r.left);
                  break;
              case Surface.ROTATION_180:
                  r.set(r.right, r.bottom, r.left, r.top);
                  break;
              case Surface.ROTATION_270:
                  r.set(r.bottom, r.left, r.top, r.right);
                  break;
              default:
                  throw new IllegalArgumentException("Unknown rotation: " + rotationDelta);
          }
      }
  
      /**
       * Adds {@code insetsToAdd} to {@code inOutInsets}.
       */
      public static void addInsets(Rect inOutInsets, Rect insetsToAdd) {
          inOutInsets.left += insetsToAdd.left;
          inOutInsets.top += insetsToAdd.top;
          inOutInsets.right += insetsToAdd.right;
          inOutInsets.bottom += insetsToAdd.bottom;
      }
  
      /**
       * Calculates the insets from the {@code outerFrame} to the {@code innerFrame}.
       *
       * Note that if a side of the outer frame is not actually on the outside, the inset for that
       * side will be clamped to zero.
       *
       * @param outerFrame the reference frame from which the insets are calculated
       * @param innerFrame the inset frame, to which the insets are calculated,
       *                   or null to clear the insets.
       * @param outInsets is set to the result of the inset calculation.
       */
      public static void insetsBetweenFrames(@NonNull Rect outerFrame, @Nullable Rect innerFrame,
              @NonNull Rect outInsets) {
          if (innerFrame == null) {
              outInsets.setEmpty();
              return;
          }
          final int w = outerFrame.width();
          final int h = outerFrame.height();
          outInsets.set(
                  Math.min(w, Math.max(0, innerFrame.left - outerFrame.left)),
                  Math.min(h, Math.max(0, innerFrame.top - outerFrame.top)),
                  Math.min(w, Math.max(0, outerFrame.right - innerFrame.right)),
                  Math.min(h, Math.max(0, outerFrame.bottom - innerFrame.bottom)));
      }
  }
  