//
   //  ========================================================================
   //  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.deploy.graph;
  
  import java.util.List;
  import java.util.concurrent.CopyOnWriteArrayList;
  
  public class Path
  {
      private final List<Edge> _edges = new CopyOnWriteArrayList<Edge>();
      private final List<Node> _nodes = new CopyOnWriteArrayList<Node>();
  
      public Path()
      {
      }
  
      public void add(Edge edge)
      {
          _edges.add(edge);
          if (_nodes.size() == 0)
          {
              _nodes.add(edge.getFrom());
          }
          else
          {
              assert _nodes.get(_nodes.size() - 1).equals(edge.getFrom());
          }
          _nodes.add(edge.getTo());
      }
  
      public Path forkPath()
      {
          Path ep = new Path();
          for (Edge edge : _edges)
          {
              ep.add(edge);
          }
          return ep;
      }
  
      public List<Node> getNodes()
      {
          return _nodes;
      }
  
      public List<Node> getEdges()
      {
          return _nodes;
      }
  
      public Node getNode(int index)
      {
          return _nodes.get(index);
      }
  
      public Node firstNode()
      {
          if (_nodes.size() == 0)
          {
              return null;
          }
          return _nodes.get(0);
      }
  
      public Node lastNode()
      {
          if (_nodes.size() == 0)
          {
              return null;
          }
          return _nodes.get(_nodes.size() - 1);
      }
  
      public int nodes()
      {
          return _nodes.size();
      }
  
      public int edges()
      {
          return _edges.size();
      }
  
     public boolean isEmpty()
     {
         return _edges.isEmpty();
     }
 
     public Edge firstEdge()
     {
         if (_edges.size() == 0)
         {
             return null;
         }
         return _edges.get(0);
     }
 
     public Edge lastEdge()
     {
         if (_edges.size() == 0)
         {
             return null;
         }
         return _edges.get(_edges.size() - 1);
     }
 
     public Edge getEdge(int index)
     {
         return _edges.get(index);
     }
 
     @Override
     public String toString()
     {
         return super.toString() + _nodes.toString();
     }
 }