/**
    * Copyright 2011-2012 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.maven.plugins.graph.dot;
  
  import java.util.ArrayList;
  
  import org.kuali.maven.plugins.graph.pojo.Edge;
  import org.kuali.maven.plugins.graph.pojo.GraphNode;
  import org.kuali.maven.plugins.graph.pojo.MavenContext;
  import org.kuali.maven.plugins.graph.pojo.Scope;
  import org.kuali.maven.plugins.graph.pojo.State;
  import org.kuali.maven.plugins.graph.pojo.Style;
  import org.kuali.maven.plugins.graph.processor.StyleProcessor;
  import org.kuali.maven.plugins.graph.tree.Node;
  import org.kuali.maven.plugins.graph.tree.TreeHelper;
  import org.kuali.maven.plugins.graph.util.Counter;
  
  /**
   * <p>
   * Draw one parent->child edge for each node in the graph.
   * </p>
   */
  public class EdgeGenerator {
      StyleProcessor sp = new StyleProcessor();
      Counter counter = new Counter(1);
  
      /**
       * <p>
       * Add this edge to the GraphNode contained in this node. If there are no edges on the GraphNode yet, create a
       * <code>List<Edge></code> and store it on the GraphNode
       * </p>
       */
      public void addEdge(Node<MavenContext> node, Edge edge) {
          MavenContext context = node.getObject();
          GraphNode graphNode = context.getGraphNode();
          if (graphNode.getEdges() == null) {
              graphNode.setEdges(new ArrayList<Edge>());
          }
          graphNode.getEdges().add(edge);
      }
  
      /**
       * <p>
       * Create an edge running from this node's parent to itself
       * </p>
       */
      public Edge getParentChildEdge(Node<MavenContext> node) {
          GraphNode parent = node.getParent().getObject().getGraphNode();
          MavenContext context = node.getObject();
          GraphNode child = context.getGraphNode();
          boolean optional = context.isOptional();
          State state = context.getState();
          Scope scope = Scope.getScope(context.getArtifact().getScope());
          return getStyledEdge(parent, child, optional, scope, state);
      }
  
      /**
       * <p>
       * Create an edge running from this node's parent to the replacement node
       * </p>
       */
      public Edge getParentChildEdge(Node<MavenContext> node, Node<MavenContext> replacement, State state) {
          GraphNode parent = node.getParent().getObject().getGraphNode();
          MavenContext context = node.getObject();
          GraphNode child = replacement.getObject().getGraphNode();
          boolean optional = context.isOptional();
          Scope scope = Scope.getScope(context.getArtifact().getScope());
          return getStyledEdge(parent, child, optional, scope, state);
      }
  
      /**
       * <p>
       * Create an edge running from this node's parent to the replacement node
       * </p>
       */
      public Edge getParentChildEdge(Node<MavenContext> node, Node<MavenContext> replacement) {
          return getParentChildEdge(node, replacement, node.getObject().getState());
      }
  
      /**
       * <p>
       * Create an edge between the indicated parent and child using styling for the indicated scope, state, and optional
       * settings
       * </p>
       */
      public Edge getStyledEdge(GraphNode parent, GraphNode child, boolean optional, Scope scope, State state) {
         Style style = sp.getStyle(scope, optional, state);
         int id = counter.increment();
         String label = TreeHelper.getRelationshipLabel(scope, optional, state);
         Edge edge = new Edge(parent, child);
         edge.setId(id);
         sp.copyStyleProperties(edge, style);
         edge.setLabel(label);
         return edge;
     }
 }