// List of Edges connecting nodes in trees -
//   designed to facilitate rotation operations
//		where an edge must be re-linked to new start and end nodes

package ciips.animation.tree;

import java.awt.*;
import java.lang.*;
import java.util.*;
import ciips.animation.*;

public class TreeEdgeList extends Vector implements DrawingObj {
	
	private static final int MIN_EDGES = 10;	
	
	private static final boolean DEBUG = false;
	
	public TreeEdgeList( ) {
		super( MIN_EDGES );
		if( DEBUG ) System.out.println("TreeEdgeList - constructed");	
		}

	public void reLink( TreeNode old_start,
									TreeNode new_start, TreeNode new_end ) {
		TreeEdge t;
		int n = size();
		for( int k=0;k<n;k++ ) {
			t = (TreeEdge)(elementAt(k));
			if ( t.getStart() == (TreeNode)old_start ) {
				t.setStart( new_start );
				t.setEnd( new_end );
				return;
				}
			}
		System.out.println( "TreeEdgeList:reLink - start (" +
															old_start + ") not found" );
		}

	public void reLink( TreeNode old_start, TreeNode old_end,
									TreeNode new_start, TreeNode new_end ) {
		TreeEdge t;
		int n = size();
		if( DEBUG ) System.out.println( "TreeEdgeList:reLink - (" +
															old_start + "-" + old_end + ")" );
		for( int k=0;k<n;k++ ) {
			t = (TreeEdge)(elementAt(k));
			if ( DEBUG ) System.out.println("TEL(" + k + ") " + t );
			if ( t.equals( old_start, old_end ) ) {
				t.setStart( new_start );
				t.setEnd( new_end );
				if( DEBUG ) System.out.println( "TreeEdgeList:reLink - found -> (" +
																				new_start + "-" + new_end + ")" );
				return;
				}
			}
		System.out.println( "TreeEdgeList:reLink - start (" +
															old_start + ") not found" );
		}

	public int getY() { return 0; }
	public int getX() { return 0; }
	public void move( int x, int y ) { }
	public void setHighlight( boolean on ) {}
	public void setGrey( boolean on ) {}

	public void draw( Graphics g ) {
		int n = size();
		if ( DEBUG ) System.out.println("TreeEdgeList:draw " + n + " edges");
		for( int k=0;k<n;k++ ) {
			DrawingObj d = (DrawingObj)elementAt(k);
			if( DEBUG ) System.out.println("TEL:draw " + (TreeEdge)d );
			d.draw( g );
			}
		}

	// public String toString() {
	// 	return "TEList (" + size() + " entries)";
	// 	}
	
	}