content: /*
   * Copyright (C) 2014 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 android.hardware.camera2.params;
  
  import android.util.Size;
  import static com.android.internal.util.Preconditions.*;
  
  import android.graphics.Point;
  import android.graphics.Rect;
  import android.hardware.camera2.CameraCharacteristics;
  import android.hardware.camera2.CaptureRequest;
  import android.hardware.camera2.utils.HashCodeHelpers;
  
  /**
   * An immutable class to represent a rectangle {@code (x, y, width, height)} with an additional
   * weight component.
   * <p>
   * The rectangle is defined to be inclusive of the specified coordinates.
   * </p>
   * <p>
   * When used with a {@link CaptureRequest}, the coordinate system is based on the active pixel
   * array, with {@code (0,0)} being the top-left pixel in the
   * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE active pixel array}, and
   * {@code (android.sensor.info.activeArraySize.width - 1,
   * android.sensor.info.activeArraySize.height - 1)} being the bottom-right pixel in the active pixel
   * array.
   * </p>
   * <p>
   * The weight must range from {@value #METERING_WEIGHT_MIN} to {@value #METERING_WEIGHT_MAX}
   * inclusively, and represents a weight for every pixel in the area. This means that a large
   * metering area with the same weight as a smaller area will have more effect in the metering
   * result. Metering areas can partially overlap and the camera device will add the weights in the
   * overlap rectangle.
   * </p>
   * <p>
   * If all rectangles have 0 weight, then no specific metering area needs to be used by the camera
   * device. If the metering rectangle is outside the used android.scaler.cropRegion returned in
   * capture result metadata, the camera device will ignore the sections outside the rectangle and
   * output the used sections in the result metadata.
   * </p>
   */
  public final class MeteringRectangle {
      /**
       * The minimum value of valid metering weight.
       */
      public static final int METERING_WEIGHT_MIN = 0;
  
      /**
       * The maximum value of valid metering weight.
       */
      public static final int METERING_WEIGHT_MAX = 1000;
  
      /**
       * Weights set to this value will cause the camera device to ignore this rectangle.
       * If all metering rectangles are weighed with 0, the camera device will choose its own metering
       * rectangles.
       */
      public static final int METERING_WEIGHT_DONT_CARE = 0;
  
      private final int mX;
      private final int mY;
      private final int mWidth;
      private final int mHeight;
      private final int mWeight;
  
      /**
       * Create a new metering rectangle.
       *
       * @param x coordinate >= 0
       * @param y coordinate >= 0
       * @param width width >= 0
       * @param height height >= 0
       * @param meteringWeight weight between {@value #METERING_WEIGHT_MIN} and
       *        {@value #METERING_WEIGHT_MAX} inclusively
       * @throws IllegalArgumentException if any of the parameters were negative
       */
      public MeteringRectangle(int x, int y, int width, int height, int meteringWeight) {
          mX = checkArgumentNonnegative(x, "x must be nonnegative");
          mY = checkArgumentNonnegative(y, "y must be nonnegative");
          mWidth = checkArgumentNonnegative(width, "width must be nonnegative");
          mHeight = checkArgumentNonnegative(height, "height must be nonnegative");
          mWeight = checkArgumentInRange(
                  meteringWeight, METERING_WEIGHT_MIN, METERING_WEIGHT_MAX, "meteringWeight");
      }
  
      /**
       * Create a new metering rectangle.
       *
       * <p>The point {@code xy}'s data is copied; the reference is not retained.</p>
       *
       * @param xy a non-{@code null} {@link Point} with both x,y >= 0
       * @param dimensions a non-{@code null} {@link android.util.Size Size} with width, height >= 0
       * @param meteringWeight weight >= 0
       *
       * @throws IllegalArgumentException if any of the parameters were negative
       * @throws NullPointerException if any of the arguments were null
       */
      public MeteringRectangle(Point xy, Size dimensions, int meteringWeight) {
          checkNotNull(xy, "xy must not be null");
          checkNotNull(dimensions, "dimensions must not be null");
  
          mX = checkArgumentNonnegative(xy.x, "x must be nonnegative");
          mY = checkArgumentNonnegative(xy.y, "y must be nonnegative");
          mWidth = checkArgumentNonnegative(dimensions.getWidth(), "width must be nonnegative");
          mHeight = checkArgumentNonnegative(dimensions.getHeight(), "height must be nonnegative");
          mWeight = checkArgumentNonnegative(meteringWeight, "meteringWeight must be nonnegative");
      }
  
      /**
       * Create a new metering rectangle.
       *
       * <p>The rectangle data is copied; the reference is not retained.</p>
       *
       * @param rect a non-{@code null} rectangle with all x,y,w,h dimensions >= 0
       * @param meteringWeight weight >= 0
       *
       * @throws IllegalArgumentException if any of the parameters were negative
       * @throws NullPointerException if any of the arguments were null
       */
      public MeteringRectangle(Rect rect, int meteringWeight) {
          checkNotNull(rect, "rect must not be null");
  
          mX = checkArgumentNonnegative(rect.left, "rect.left must be nonnegative");
          mY = checkArgumentNonnegative(rect.top, "rect.top must be nonnegative");
          mWidth = checkArgumentNonnegative(rect.width(), "rect.width must be nonnegative");
          mHeight = checkArgumentNonnegative(rect.height(), "rect.height must be nonnegative");
          mWeight = checkArgumentNonnegative(meteringWeight, "meteringWeight must be nonnegative");
      }
  
      /**
       * Return the X coordinate of the left side of the rectangle.
       *
       * @return x coordinate >= 0
       */
      public int getX() {
          return mX;
      }
  
      /**
       * Return the Y coordinate of the upper side of the rectangle.
       *
       * @return y coordinate >= 0
       */
      public int getY() {
          return mY;
      }
  
      /**
       * Return the width of the rectangle.
       *
       * @return width >= 0
       */
      public int getWidth() {
          return mWidth;
      }
  
      /**
       * Return the height of the rectangle.
       *
       * @return height >= 0
       */
      public int getHeight() {
          return mHeight;
      }
  
      /**
       * Return the metering weight of the rectangle.
       *
       * @return weight >= 0
       */
      public int getMeteringWeight() {
          return mWeight;
      }
  
      /**
       * Convenience method to create the upper-left (X,Y) coordinate as a {@link Point}.
       *
       * @return a new {@code (x,y)} {@link Point} with both x,y >= 0
       */
      public Point getUpperLeftPoint() {
          return new Point(mX, mY);
      }
  
      /**
       * Convenience method to create the size from this metering rectangle.
       *
       * <p>This strips away the X,Y,weight from the rectangle.</p>
       *
       * @return a new {@link Size} with non-negative width and height
       */
      public Size getSize() {
          return new Size(mWidth, mHeight);
      }
  
      /**
       * Convenience method to create a {@link Rect} from this metering rectangle.
       *
       * <p>This strips away the weight from the rectangle.</p>
       *
       * @return a new {@link Rect} with non-negative x1, y1, x2, y2
       */
      public Rect getRect() {
          return new Rect(mX, mY, mX + mWidth, mY + mHeight);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public boolean equals(final Object other) {
          return other instanceof MeteringRectangle && equals((MeteringRectangle)other);
      }
  
      /**
       * Compare two metering rectangles to see if they are equal.
       *
       * Two weighted rectangles are only considered equal if each of their components
       * (x, y, width, height, weight) is respectively equal.
       *
       * @param other Another MeteringRectangle
       *
       * @return {@code true} if the metering rectangles are equal, {@code false} otherwise
       */
      public boolean equals(final MeteringRectangle other) {
          if (other == null) {
              return false;
          }
  
          return (mX == other.mX
                  && mY == other.mY
                  && mWidth == other.mWidth
                  && mHeight == other.mHeight
                  && mWeight == other.mWeight);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public int hashCode() {
          return HashCodeHelpers.hashCode(mX, mY, mWidth, mHeight, mWeight);
      }
  
      /**
       * Return the metering rectangle as a string representation
       * {@code "(x:%d, y:%d, w:%d, h:%d, wt:%d)"} where each {@code %d} respectively represents
       * the x, y, width, height, and weight points.
       *
       * @return string representation of the metering rectangle
       */
      @Override
      public String toString() {
          return String.format("(x:%d, y:%d, w:%d, h:%d, wt:%d)", mX, mY, mWidth, mHeight, mWeight);
      }
  }
  