package org.djutils.draw.bounds;
   
   import java.awt.geom.Rectangle2D;
   import java.util.Arrays;
   import java.util.Collection;
   import java.util.Iterator;
   import java.util.Locale;
   
   import org.djutils.draw.Drawable2d;
  import org.djutils.draw.point.Point2d;
  import org.djutils.exceptions.Throw;
  
  /**
   * A Bounds2d stores the rectangular 2D bounds of a 2d object, or a collection of 2d objects. The Bounds2d is an immutable
   * object.
   * <p>
   * Copyright (c) 2020-2022 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
   * BSD-style license. See <a href="https://djutils.org/docs/current/djutils/licenses.html">DJUTILS License</a>.
   * </p>
   * @author <a href="https://www.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   * @author <a href="https://www.tudelft.nl/pknoppers">Peter Knoppers</a>
   */
  public class Bounds2d implements Drawable2d, Bounds<Bounds2d, Point2d, Drawable2d>
  {
      /** */
      private static final long serialVersionUID = 20200829L;
  
      /** The lower bound for x. */
      private final double minX;
  
      /** The lower bound for y. */
      private final double minY;
  
      /** The upper bound for x. */
      private final double maxX;
  
      /** The upper bound for y. */
      private final double maxY;
  
      /**
       * Construct a Bounds2d by providing its lower and upper bounds in both dimensions.
       * @param minX double; the lower bound for x
       * @param maxX double; the upper bound for x
       * @param minY double; the lower bound for y
       * @param maxY double; the upper bound for y
       * @throws IllegalArgumentException when a lower bound is larger than the corresponding upper bound, or any of the bounds is
       *             NaN
       */
      public Bounds2d(final double minX, final double maxX, final double minY, final double maxY) throws IllegalArgumentException
      {
          Throw.when(Double.isNaN(minX) || Double.isNaN(maxX) || Double.isNaN(minY) || Double.isNaN(maxY),
                  IllegalArgumentException.class, "bounds must be numbers (not NaN)");
          Throw.when(minX > maxX || minY > maxY, IllegalArgumentException.class,
                  "lower bound for each dimension should be less than or equal to its upper bound");
          this.minX = minX;
          this.minY = minY;
          this.maxX = maxX;
          this.maxY = maxY;
      }
  
      /**
       * Constructs a new Bounds2d around the origin (0, 0).
       * @param deltaX double; the deltaX value around the origin
       * @param deltaY double; the deltaY value around the origin
       * @throws IllegalArgumentException when one of the delta values is less than zero
       */
      public Bounds2d(final double deltaX, final double deltaY)
      {
          this(-0.5 * deltaX, 0.5 * deltaX, -0.5 * deltaY, 0.5 * deltaY);
      }
  
      /**
       * Construct a Bounds2d from some collection of points, finding the lowest and highest x and y coordinates.
       * @param points Iterator&lt;? extends Point2d&gt;; Iterator that will generate all the points for which to construct a
       *            Bounds2d
       * @throws NullPointerException when points is null
       * @throws IllegalArgumentException when the iterator provides zero points
       */
      public Bounds2d(final Iterator<? extends Point2d> points)
      {
          Throw.whenNull(points, "points may not be null");
          Throw.when(!points.hasNext(), IllegalArgumentException.class, "need at least one point");
          Point2d point = points.next();
          double tempMinX = point.x;
          double tempMaxX = point.x;
          double tempMinY = point.y;
          double tempMaxY = point.y;
          while (points.hasNext())
          {
              point = points.next();
              tempMinX = Math.min(tempMinX, point.x);
              tempMaxX = Math.max(tempMaxX, point.x);
              tempMinY = Math.min(tempMinY, point.y);
              tempMaxY = Math.max(tempMaxY, point.y);
          }
          this.minX = tempMinX;
          this.maxX = tempMaxX;
          this.minY = tempMinY;
          this.maxY = tempMaxY;
     }
 
     /**
      * Construct a Bounds2d from an array of Point2d, finding the lowest and highest x and y coordinates.
      * @param points Point2d[]; the points to construct a Bounds2d from
      * @throws NullPointerException when points is null
      * @throws IllegalArgumentException when zero points are provided
      */
     public Bounds2d(final Point2d[] points) throws NullPointerException, IllegalArgumentException
     {
         this(Arrays.stream(Throw.whenNull(points, "points may not be null")).iterator());
     }
 
     /**
      * Construct a Bounds2d for a Drawable2d.
      * @param drawable2d Drawable2d; any object that implements the Drawable2d interface
      * @throws NullPointerException when drawable2d is null
      */
     public Bounds2d(final Drawable2d drawable2d) throws NullPointerException
     {
         this(Throw.whenNull(drawable2d, "drawable2d may not be null").getPoints());
     }
 
     /**
      * Construct a Bounds2d for several Drawable2d objects.
      * @param drawable2d Drawable2d...; the Drawable2d objects
      * @throws NullPointerException when the array is null, or contains a null value
      * @throws IllegalArgumentException when the length of the array is 0
      */
     public Bounds2d(final Drawable2d... drawable2d) throws NullPointerException, IllegalArgumentException
     {
         this(pointsOf(drawable2d));
     }
 
     /**
      * Verify that the array contains at least one entry.
      * @param drawable2dArray Drawable2d[]; array of Drawable2d objects
      * @return Drawable2d[]; the array
      * @throws NullPointerException when the array is null
      * @throws IllegalArgumentException when the array contains 0 elements
      */
     static Drawable2d[] ensureHasOne(final Drawable2d[] drawable2dArray) throws NullPointerException, IllegalArgumentException
     {
         Throw.whenNull(drawable2dArray, "Array may not be null");
         Throw.when(drawable2dArray.length == 0, IllegalArgumentException.class, "Array must contain at least one value");
         return drawable2dArray;
     }
 
     /**
      * Return an iterator that will return all points of one or more Drawable objects.
      * @param drawable2d Drawable2d...; the Drawable objects
      * @return Iterator&lt;P&gt;; iterator that will return all points of the Drawable objects
      * @throws NullPointerException when drawable is null, or contains a null value
      * @throws IllegalArgumentException when drawable is empty
      */
     public static Iterator<Point2d> pointsOf(final Drawable2d... drawable2d)
     {
         return new Iterator<Point2d>()
         {
             /** Index in the argument array. */
             private int nextArgument = 0;
 
             /** Iterator over the Point2d objects in the current Drawable2d. */
             private Iterator<? extends Point2d> currentIterator = ensureHasOne(drawable2d)[0].getPoints();
 
             @Override
             public boolean hasNext()
             {
                 return this.nextArgument < drawable2d.length - 1 || this.currentIterator.hasNext();
             }
 
             @Override
             public Point2d next()
             {
                 if (this.currentIterator.hasNext())
                 {
                     return this.currentIterator.next();
                 }
                 // Move to next Drawable2d
                 this.nextArgument++;
                 this.currentIterator = drawable2d[this.nextArgument].getPoints();
                 return this.currentIterator.next(); // Cannot fail because every Drawable has at least one point
             }
         };
     }
 
     /**
      * Construct a Bounds2d for a Collection of Drawable2d objects.
      * @param drawableCollection Collection&lt;Drawable2d&gt;; the collection
      * @throws NullPointerException when the collection is null, or contains null values
      * @throws IllegalArgumentException when the collection is empty
      */
     public Bounds2d(final Collection<Drawable2d> drawableCollection) throws NullPointerException, IllegalArgumentException
     {
         this(pointsOf(drawableCollection));
     }
 
     /**
      * Return an iterator that will return all points of one or more Drawable2d objects.
      * @param drawableCollection Collection&lt;Drawable2d&gt;; the collection of Drawable2d objects
      * @return Iterator&lt;P&gt;; iterator that will return all points of the Drawable objects
      * @throws NullPointerException when drawableCollection is null, or contains a null value
      * @throws IllegalArgumentException when drawableCollection is empty
      */
     public static Iterator<Point2d> pointsOf(final Collection<Drawable2d> drawableCollection)
             throws NullPointerException, IllegalArgumentException
     {
         return new Iterator<Point2d>()
         {
             /** Iterator that iterates over the collection. */
             private Iterator<Drawable2d> collectionIterator = ensureHasOne(drawableCollection.iterator());
 
             /** Iterator that generates Point2d objects for the currently selected element of the collection. */
             private Iterator<? extends Point2d> currentIterator = this.collectionIterator.next().getPoints();
 
             @Override
             public boolean hasNext()
             {
                 if (this.currentIterator == null)
                 {
                     return false;
                 }
                 return this.currentIterator.hasNext();
             }
 
             @Override
             public Point2d next()
             {
                 Point2d result = this.currentIterator.next();
                 if (!this.currentIterator.hasNext())
                 {
                     if (this.collectionIterator.hasNext())
                     {
                         this.currentIterator = this.collectionIterator.next().getPoints();
                     }
                     else
                     {
                         this.currentIterator = null;
                     }
                 }
                 return result;
             }
         };
     }
 
     /**
      * Verify that the iterator has something to return.
      * @param iterator Iterator&lt;Drawable2d&gt;; the iterator
      * @return Iterator&lt;Drawable2d&gt;; the iterator
      * @throws NullPointerException when the iterator is null
      * @throws IllegalArgumentException when the hasNext method of the iterator returns false
      */
     public static Iterator<Drawable2d> ensureHasOne(final Iterator<Drawable2d> iterator)
             throws NullPointerException, IllegalArgumentException
     {
         Throw.when(!iterator.hasNext(), IllegalArgumentException.class, "Collection may not be empty");
         return iterator;
     }
 
     /** {@inheritDoc} */
     @Override
     public Iterator<Point2d> getPoints()
     {
         Point2d[] array = new Point2d[] { new Point2d(this.minX, this.minY), new Point2d(this.minX, this.maxY),
                 new Point2d(this.maxX, this.minY), new Point2d(this.maxX, this.maxY) };
         return Arrays.stream(array).iterator();
     }
 
     /** {@inheritDoc} */
     @Override
     public int size()
     {
         return 4;
     }
 
     /**
      * Check if this Bounds2d contains a point. Contains considers a point <b>on</b> the border of this Bounds2d to be outside.
      * @param x double; the x-coordinate of the point
      * @param y double; the y-coordinate of the point
      * @return boolean; whether this Bounds2d contains the point
      * @throws IllegalArgumentException when any of the coordinates is NaN
      */
     public boolean contains(final double x, final double y) throws IllegalArgumentException
     {
         Throw.when(Double.isNaN(x) || Double.isNaN(y), IllegalArgumentException.class, "coordinates must be numbers (not NaN)");
         return x > this.minX && x < this.maxX && y > this.minY && y < this.maxY;
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean contains(final Point2d point)
     {
         Throw.whenNull(point, "point cannot be null");
         return contains(point.x, point.y);
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean contains(final Drawable2d drawable) throws NullPointerException
     {
         Throw.whenNull(drawable, "drawable cannot be null");
         Bounds2d bounds = drawable.getBounds();
         return contains(bounds.minX, bounds.minY) && contains(bounds.maxX, bounds.maxY);
     }
 
     /**
      * Check if this Bounds2d covers a point. Covers returns true when the point is on, or inside this Bounds2d.
      * @param x double; the x-coordinate of the point
      * @param y double; the y-coordinate of the point
      * @return boolean; whether this Bounds2d, including its borders, contains the point
      */
     public boolean covers(final double x, final double y)
     {
         Throw.when(Double.isNaN(x) || Double.isNaN(y), IllegalArgumentException.class, "coordinates must be numbers (not NaN)");
         return x >= this.minX && x <= this.maxX && y >= this.minY && y <= this.maxY;
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean covers(final Point2d point)
     {
         Throw.whenNull(point, "point cannot be null");
         return covers(point.x, point.y);
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean covers(final Drawable2d drawable) throws NullPointerException
     {
         Throw.whenNull(drawable, "drawable cannot be null");
         Bounds2d bounds = drawable.getBounds();
         return covers(bounds.minX, bounds.minY) && covers(bounds.maxX, bounds.maxY);
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean disjoint(final Drawable2d drawable) throws NullPointerException
     {
         Throw.whenNull(drawable, "drawable cannot be null");
         Bounds2d bounds = drawable.getBounds();
         return bounds.minX >= this.maxX || bounds.maxX <= this.minX || bounds.minY >= this.maxY || bounds.maxY <= this.minY;
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean intersects(final Bounds2d otherBounds2d) throws NullPointerException
     {
         return !disjoint(otherBounds2d);
     }
 
     /** {@inheritDoc} */
     @Override
     public Bounds2d intersection(final Bounds2d otherBounds2d)
     {
         Throw.whenNull(otherBounds2d, "otherBounds2d cannot be null");
         if (disjoint(otherBounds2d))
         {
             return null;
         }
         return new Bounds2d(Math.max(this.minX, otherBounds2d.minX), Math.min(this.maxX, otherBounds2d.maxX),
                 Math.max(this.minY, otherBounds2d.minY), Math.min(this.maxY, otherBounds2d.maxY));
     }
 
     /**
      * Return an AWT Rectangle2D that covers the same area as this Bounds2d.
      * @return Rectangle2D; the rectangle that covers the same area as this Bounds2d
      */
     public Rectangle2D toRectangle2D()
     {
         return new Rectangle2D.Double(this.minX, this.minY, this.maxX - this.minX, this.maxY - this.minY);
     }
 
     /** {@inheritDoc} */
     @Override
     public double getMinX()
     {
         return this.minX;
     }
 
     /** {@inheritDoc} */
     @Override
     public double getMaxX()
     {
         return this.maxX;
     }
 
     /** {@inheritDoc} */
     @Override
     public double getMinY()
     {
         return this.minY;
     }
 
     /** {@inheritDoc} */
     @Override
     public double getMaxY()
     {
         return this.maxY;
     }
 
     /** {@inheritDoc} */
     @Override
     public Point2d midPoint()
     {
         return new Point2d((this.minX + this.maxX) / 2, (this.minY + this.maxY) / 2);
     }
 
     /**
      * Return the area of this Bounds2d.
      * @return double; the area of this Bounds2d
      */
     public double getArea()
     {
         return getDeltaX() * getDeltaY();
     }
 
     /** {@inheritDoc} */
     @Override
     public Bounds2d getBounds()
     {
         return this;
     }
 
     /** {@inheritDoc} */
     @Override
     public String toString()
     {
         return toString("%f");
     }
 
     /** {@inheritDoc} */
     @Override
     public String toString(final String doubleFormat, final boolean doNotIncludeClassName)
     {
         String format =
                 String.format("%1$s[x[%2$s : %2$s], y[%2$s : %2$s]]", doNotIncludeClassName ? "" : "Bounds2d ", doubleFormat);
         return String.format(Locale.US, format, this.minX, this.maxX, this.minY, this.maxY);
     }
 
     /** {@inheritDoc} */
     @Override
     public int hashCode()
     {
         final int prime = 31;
         int result = 1;
         long temp;
         temp = Double.doubleToLongBits(this.maxX);
         result = prime * result + (int) (temp ^ (temp >>> 32));
         temp = Double.doubleToLongBits(this.maxY);
         result = prime * result + (int) (temp ^ (temp >>> 32));
         temp = Double.doubleToLongBits(this.minX);
         result = prime * result + (int) (temp ^ (temp >>> 32));
         temp = Double.doubleToLongBits(this.minY);
         result = prime * result + (int) (temp ^ (temp >>> 32));
         return result;
     }
 
     /** {@inheritDoc} */
     @SuppressWarnings("checkstyle:needbraces")
     @Override
     public boolean equals(final Object obj)
     {
         if (this == obj)
             return true;
         if (obj == null)
             return false;
         if (getClass() != obj.getClass())
             return false;
         Bounds2d other = (Bounds2d) obj;
         if (Double.doubleToLongBits(this.maxX) != Double.doubleToLongBits(other.maxX))
             return false;
         if (Double.doubleToLongBits(this.maxY) != Double.doubleToLongBits(other.maxY))
             return false;
         if (Double.doubleToLongBits(this.minX) != Double.doubleToLongBits(other.minX))
             return false;
         if (Double.doubleToLongBits(this.minY) != Double.doubleToLongBits(other.minY))
             return false;
         return true;
     }
 
 }