import java.awt.*;
import java.util.*;
import java.awt.geom.*;
import java.io.*;
import java.util.*;
import java.util.List;



/**
 * Make a diagram editor that allows for the drawing of hosts, routers,
 * and network connections.
 *
 * @author Eric Lemar
 */
public class NetworkDiagram extends Graph
{
   public NetworkDiagram() {
      super();
   }

   public Node[] getNodePrototypes()
   {
      Node[] nodeTypes = {
         new RouterNode(),
         new HostNode()
      };
      return nodeTypes;
   }

   public Edge[] getEdgePrototypes()
   {
      Edge[] edgeTypes = {
         new NetworkEdge()
      };
      return edgeTypes;
   }

   /**
    * Connect two nodes together.
    *
    * Returns false if there isn't a node at one of the two points or
    * if the edge is of type NetworkEdge and  violates one of the constraints
    * of how network nodes can be connected to each other.  These constraints
    * are defined in the NetworkEdge and NetworkNode classes.
    *
    * @param e The new edge
    * @param p1 The location to look for the first node
    * @param p2 The location to look for the second node
    * @return <code>true</code> if added, <code>false</code> otherwise.
    */
   public boolean connect(Edge e, Point2D p1, Point2D p2)
   {
      Node n1 = findNode(p1);
      Node n2 = findNode(p2);
      if (n1 != null && n2 != null) {
         if (e instanceof NetworkEdge) {
            NetworkEdge me=(NetworkEdge)e;
           
            if (me.approvedConnect(n1,n2)) {
               super.connect(e,p1,p2);
               return true;
            }
            return false;
         } else {
            super.connect(e,p1,p2);
            return true;
         }
      }
      return false;
   }

   /**
    * Remove an edge. 
    *
    * This method also signals the edge if a NetworkEdge to tell inform it that
    * it's being removed.
    *
    * @param e The edge to remove
    */
   public void removeEdge(Edge e){
      if (e instanceof NetworkEdge) {
         NetworkEdge ne=(NetworkEdge)e;
         ne.signalRemove();
      }
      super.removeEdge(e);
   }

   /**
    * Remove an node. 
    *
    * This method also signals all of the connected edges to tell them
    * they are being removed
    *
    * @param e The edge to remove
    */
   public void removeNode(Node n) {
      List edges  = getEdges();
      Iterator it = edges.iterator();

      while (it.hasNext()) {
         Edge e = (Edge)it.next();
         if (e.getStart() == n || e.getEnd() == n) {
            if (e instanceof NetworkEdge) {
               NetworkEdge ne=(NetworkEdge)e;
               ne.signalRemove();
            }
         }
      }
      super.removeNode(n);
   }

}