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package algs32.kdtree;
import java.util.TreeSet;
import algs12.Point2D;
import stdlib.*;
/* ***********************************************************************
 *  Compilation:  javac RangeSearchVisualizer.java
 *  Execution:    java RangeSearchVisualizer input.txt
 *  Dependencies: PointSET.java KdTree.java Point2D.java RectHV.java
 *                StdDraw.java In.java
 *
 *  Read points from a file (specified as a command-line arugment) and
 *  draw to standard draw. Also draw all of the points in the rectangle
 *  the user selects by dragging the mouse.
 *
 *  The range search results using the brute-force algorithm are drawn
 *  in red; the results using the kd-tree algorithms are drawn in blue.
 *
 *************************************************************************/

public class RangeSearchVisualizer {

  public static void main(String[] args) {
    //args = new String [] { "src/algs32/kdtree/kdtree-input10K.txt" };
    //args = new String [] { "src/algs32/kdtree/kdtree-circle4.txt" };
    //args = new String [] { "src/algs32/kdtree/kdtree-circle10.txt" };
    //args = new String [] { "src/algs32/kdtree/kdtree-circle100.txt" };
    //args = new String [] { "src/algs32/kdtree/kdtree-horizontal8.txt" };
    //args = new String [] { "src/algs32/kdtree/kdtree-vertical7.txt" };
    args = new String [] { "src/algs32/kdtree/kdtree-random500.txt" };

    String filename = args[0];
    In in = new In(filename);


    StdDraw.show(0);

    // initialize the data structures with N points from standard input
    PointSET brute = new PointSET();
    KdTree kdtree = new KdTree();
    while (!in.isEmpty()) {
      double x = in.readDouble();
      double y = in.readDouble();
      Point2D p = new Point2D(x, y);
      kdtree.insert(p);
      brute.insert(p);
    }

    double x0 = 0.0, y0 = 0.0;      // initial endpoint of rectangle
    double x1 = 0.0, y1 = 0.0;      // current location of mouse
    boolean isDragging = false;     // is the user dragging a rectangle

    // draw the points
    StdDraw.clear();
    StdDraw.setPenColor(StdDraw.BLACK);
    StdDraw.setPenRadius(.01);
    brute.draw();

    while (true) {
      StdDraw.show(40);

      // user starts to drag a rectangle
      if (StdDraw.mousePressed() && !isDragging) {
        x0 = StdDraw.mouseX();
        y0 = StdDraw.mouseY();
        isDragging = true;
        continue;
      }

      // user is dragging a rectangle
      else if (StdDraw.mousePressed() && isDragging) {
        x1 = StdDraw.mouseX();
        y1 = StdDraw.mouseY();
        continue;
      }

      // mouse no longer pressed
      else if (!StdDraw.mousePressed() && isDragging) {
        isDragging = false;
      }


      RectHV rect = new RectHV(Math.min(x0, x1), Math.min(y0, y1),
          Math.max(x0, x1), Math.max(y0, y1));
      // draw the points
      StdDraw.clear();
      StdDraw.setPenColor(StdDraw.BLACK);
      StdDraw.setPenRadius(.01);
      brute.draw();

      // draw the rectangle
      StdDraw.setPenColor(StdDraw.BLACK);
      StdDraw.setPenRadius();
      rect.draw();

      // draw the range search results for brute-force data structure in red
      StdDraw.setPenRadius(.03);
      StdDraw.setPenColor(StdDraw.RED);
      for (Point2D p : brute.range(rect))
        p.draw();

      // draw the range search results for kd-tree in blue
      StdDraw.setPenRadius(.02);
      StdDraw.setPenColor(StdDraw.BLUE);
      for (Point2D p : kdtree.range(rect))
        p.draw();

      StdDraw.show(40);

      // check to see that the results are the same
      TreeSet<Point2D> set = new TreeSet<> ();
      for (Point2D p : brute.range(rect))
        set.add (p);
      for (Point2D p : kdtree.range(rect))
        if (! set.remove (p)) StdOut.format ("KdTree has extra %s\n", p);
      for (Point2D p : set)
        StdOut.format ("KdTree missed %s\n", p);
    }
  }
}