package tsp.solutionAlgorithms.simha;

import edu.gwu.champAlg.*;
import tsp.*;
import java.util.*;

public class NearestNeighbor implements SolutionAlgorithm {

    Pointd[] points;

    public String getName ()
    {
	return "Simha-TSP-NearestNeighbor";
    }

    public String toString ()
    {
	return "SimhaTSPNN";
    }

    public void setPropertyExtractor (int algID, PropertyExtractor prop)
    {
    }

    public Solution solve (Problem problem)
    {
	TSPProblem tProblem = (TSPProblem) problem;
	this.points = tProblem.points;

	int[] tour = new int [points.length];

        // INSERT YOUR CODE HERE

	TSPSolution tSolution = new TSPSolution ();
	tSolution.tour = tour;
	return tSolution;
    }



    double cost (int[] tour)
    {
	double c = 0;
	for (int i=0; i<tour.length-1; i++) {
	    c += distance (points[tour[i]], points[tour[i+1]]);
	}
	c += distance (points[tour[tour.length-1]], points[tour[0]]);
	return c;
    }

    double distance (Pointd p, Pointd q)
    {
	return Math.sqrt ((p.x-q.x)*(p.x-q.x) + (p.y-q.y)*(p.y-q.y));
    }


    public void invalidSolution (Problem problem, Solution solution)
    {
	// Print error message in TSPSolution.
	TSPSolution tSolution = (TSPSolution) solution;
	System.out.println (tSolution.getErrorMessage());
    }

}