/*
 * Copyright (c) 2005-2007, ASTcentric group, All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * 
 * - Redistributions of source code must retain the above copyright notice, 
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice, 
 *   this list of conditions and the following disclaimer in the documentation 
 *   and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */
/*
 * Created on 02.06.2007
 */
package astcentric.example.properties;

import java.util.List;
import java.util.Properties;

import astcentric.structure.basic.AST;
import astcentric.structure.basic.Node;
import astcentric.structure.basic.NodeException;
import astcentric.structure.basic.NodeHandler;
import astcentric.structure.basic.NodeTool;
import astcentric.structure.basic.id.ASTID;

public class PropertiesGenerator
{
  private static class PropertiesDeclaration
  {
    private static final ASTID PROPERTIES_DECLARATION_AST_ID 
                           = new ASTID("astcentric.sf.net", "fjelmer", 1);

    private final Node plainValueNode;
    private final Node valueReferenceNode;
    private final Node propertyNode;

    PropertiesDeclaration(AST ast)
    {
      if (ast.getInfo().getID().equals(PROPERTIES_DECLARATION_AST_ID) == false)
      {
        throw new IllegalArgumentException(
                "Properties Declaration AST expected instead of: " + ast);
      }
      List<Node> visibleNodes = NodeTool.collectNodesVisibleFor(ast, ast);
      plainValueNode = visibleNodes.get(1);
      valueReferenceNode = visibleNodes.get(2);
      propertyNode = visibleNodes.get(3);
    }
  }
  
  public static Properties generate(Node propertiesNode)
  {
    Node reference = propertiesNode.getReference();
    if (reference == null)
    {
      throw new NodeException(propertiesNode,
                              "Reference to Properties Declaration missing");
    }
    AST ast = reference.getAST();
    PropertiesDeclaration declaration = new PropertiesDeclaration(ast);
    Properties properties = new Properties();
    List<Node> propNodes = NodeTool.getNodesOf(propertiesNode);
    for (Node propNode : propNodes)
    {
      String name = propNode.getName();
      if (name == null)
      {
        throw new NodeException(propNode, "Nameless property node.");
      }
      properties.setProperty(name, getValue(propNode, declaration));
    }
    return properties;
  }
  
  private static String getValue(Node node, 
                                 final PropertiesDeclaration declaration)
  {
    Node reference = node.getReference();
    if (reference == null)
    {
      throw new NodeException(node, "Missing reference.");
    }
    if (NodeTool.same(reference, declaration.plainValueNode))
    {
      return node.getValue().toString();
    } 
    if (NodeTool.same(reference, declaration.valueReferenceNode))
    {
      Node ref = NodeTool.getNodesOf(node).get(0).getReference();
      return getValue(ref, declaration);
    }
    if (NodeTool.same(reference, declaration.propertyNode))
    {
      final StringBuilder builder = new StringBuilder();
      node.traverseNodes(new NodeHandler()
        {
          public boolean handle(Node child)
          {
            builder.append(getValue(child, declaration));
            return false;
          }
        });
      return new String(builder);
    }
    throw new NodeException(node, "Isn't declared correctly: " + reference);
  }

  private PropertiesGenerator() {}
}