package algs32.kdtree;
import algs12.Point2D;
import stdlib.*;
/* ***********************************************************************
 *  Compilation:  javac NearestNeighborVisualizer.java
 *  Execution:    java NearestNeighborVisualizer input.txt
 *  Dependencies: PointSET.java KdTree.java Point2D.java In.java StdDraw.java
 *
 *  Read points from a file (specified as a command-line argument) and
 *  draw to standard draw. Highlight the closest point to the mouse.
 *
 *  The nearest neighbor according to the brute-force algorithm is drawn
 *  in red; the nearest neighbor using the kd-tree algorithm is drawn in blue.
 *
 *************************************************************************/

public class NearestNeighborVisualizer {

  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" };

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

    StdDraw.show(0);

    // initialize the two data structures with point 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);
    }

    while (true) {

      // the location (x, y) of the mouse
      double x = StdDraw.mouseX();
      double y = StdDraw.mouseY();
      Point2D query = new Point2D(x, y);
      // query = new Point2D(.5, .5);
      Point2D b = brute.nearest(query);
      Point2D k = kdtree.nearest (query);
      double diff = query.distanceTo(b) - query.distanceTo (k);
      if (diff != 0.0) StdOut.format ("diff = %f\n", diff);

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

      // draw in red the nearest neighbor according to the brute-force algorithm
      StdDraw.setPenRadius(.03);
      StdDraw.setPenColor(StdDraw.RED);
      b.draw();

      // draw in blue the nearest neighbor according to the kd-tree algorithm
      StdDraw.setPenRadius(.02);
      StdDraw.setPenColor(StdDraw.BLUE);
      k.draw();

      StdDraw.show(0);
      StdDraw.show(40);
    }
  }
}