import java.io.*;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
import java.util.StringTokenizer;

import Jcg.viewer.old.Fenetre;
import Jcg.geometry.GeometricOperations_2;
import Jcg.geometry.kernel.*;
import Jcg.geometry.Point_2;
import Jcg.geometry.Ray_2;
import Jcg.geometry.Segment_2;
import Jcg.geometry.Vector_2;
import Jcg.triangulations2D.Delaunay_2;
import Jcg.triangulations2D.HalfedgeHandle;
import Jcg.triangulations2D.TriangulationDSFace_2;

public class RayCast {

	// public parameters
	public Point_2 position;  // viewer's position
	public int orientation;  // viewer's orientation (in degrees compared to abcissa unit vector)
	public int viewAngle;  // viewing angle (in degrees)
	public int viewSize;  // size of the view window, in pixels
	public double [] distancesToObstacles;  // output of raycast 
	public double [] distancesToObstaclesBound;  // output of raycast 
	
	// private data structures
	Delaunay_2 del;  // data structure for ray casting amongst obstacles
	private Map map;
	
	public RayCast (String filename, int viewAngle, int viewSize, 
			Point_2 initialPosition, int initialOrientation) throws IOException {
		this.viewAngle = viewAngle;
		this.viewSize = viewSize;
		this.position = initialPosition;
		this.orientation = initialOrientation;
		distancesToObstacles = new double [viewSize];
		distancesToObstaclesBound = new double [viewSize];
		
		del = new Delaunay_2();
		readConstraints(filename);
	}

	private void readConstraints(String filename) throws IOException {
    	File file;
    	FileReader readfic;
    	BufferedReader input;
    	String line;
    	System.out.print(" --- Reading obstacles file " + filename + "...");
    	file = new File(filename);
    	readfic = new FileReader(file);
    	input = new BufferedReader(readfic);
            
    	while ((line=input.readLine()) != null) {
//    		System.out.println ("line=" + line);
    		StringTokenizer tok = new StringTokenizer(line);
    		double px=Double.parseDouble(tok.nextToken());
    		double py=Double.parseDouble(tok.nextToken());            
    		Point_2 p = new Point_2(px, py);
    		double qx=Double.parseDouble(tok.nextToken());
    		double qy=Double.parseDouble(tok.nextToken());            
    		Point_2 q = new Point_2(qx, qy);
//   		System.out.print("Inserting constraint edge [" + p + ";" + q + "]...");
    		del.insert(p, q);
//    		System.out.println(" done");
    	}
    	input.close();
    	System.out.println(" done");
	}	
  		
	
	
	/*
	 * Returns first constrained HalfedgeHandle that intersects the ray. 
	 * Returns null if no such intersection exists.
	 * Initial assumption: the input HalfedgeHandle e belongs to a face containing the origin of the ray
	 */ 
	public HalfedgeHandle<Point_2> castRay (Ray_2 r, HalfedgeHandle<Point_2> e) {
	    ///////////////////////////////////////////////////////
		// throw new Error ("a completer");
		///////////////////////////////////////////////////////
		return null;
	}
	
	/*
	 *  Casts all rays from viewer and records corresponding distances to viewer 
	 *  in the field distancesToObstacles
	 */
	public void castRays () {
	    ///////////////////////////////////////////////////////
		// throw new Error ("a completer");
		///////////////////////////////////////////////////////
	}
	

	/**
	 * @param args
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException {
		if (args.length != 1) {
			System.out.println("Usage : java RayCast <filename>");
			return;
		}

		final int viewAngle = 45;
		final int viewSize = 600;
		RayCast r = new RayCast(args[0], viewAngle, viewSize, new Point_2(-1.5,1.2), -45);
		r.castRays();
		// RayCastWindow f = new RayCastWindow (r);
		Map map = new Map(r);
		Collection<TriangulationDSFace_2<Point_2>> facesDel = r.del.finiteFaces();
		LinkedList<Point_2[]> trianglesDel = new LinkedList<Point_2[]>();
		for (TriangulationDSFace_2<Point_2> f : facesDel)
			trianglesDel.add(new Point_2[]{f.vertex(0).getPoint(), f.vertex(1).getPoint(), f.vertex(2).getPoint()});
		Collection<HalfedgeHandle<Point_2>> cEdgesDel = r.del.constraintEdges();
		LinkedList<Point_2[]> cSegmentsDel = new LinkedList<Point_2[]> ();
		for (HalfedgeHandle<Point_2> e : cEdgesDel)
			cSegmentsDel.add(new Point_2[]{e.getVertex(0).getPoint(), e.getVertex(1).getPoint()});
		map.addTriangles(trianglesDel);
		map.addFatSegments(cSegmentsDel);	
		}

}