/*
    * Copyright 2007-2013 smartics, Kronseder & Reiner GmbH
    *
    * Licensed under the Apache 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.apache.org/licenses/LICENSE-2.0
    *
   * 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 de.smartics.exceptions.report.renderer.html;
  
  import org.apache.commons.lang.StringUtils;
  
  import com.thoughtworks.qdox.model.DocletTag;
  import com.thoughtworks.qdox.model.JavaAnnotatedElement;
  import com.thoughtworks.qdox.model.JavaClass;
  import com.thoughtworks.qdox.model.JavaField;
  
  import de.smartics.exceptions.report.renderer.ValueTagRenderer;
  
  /**
   * Default implementation that renders the value tags as HTML.
   */
  public class HtmlValueTagRenderer implements ValueTagRenderer
  {
    // ********************************* Fields *********************************
  
    // --- constants ------------------------------------------------------------
  
    // --- members --------------------------------------------------------------
  
    // ****************************** Initializer *******************************
  
    // ****************************** Constructors ******************************
  
    // ****************************** Inner Classes *****************************
  
    // ********************************* Methods ********************************
  
    // --- init -----------------------------------------------------------------
  
    // --- get&set --------------------------------------------------------------
  
    // --- business -------------------------------------------------------------
  
    @Override
    public StringBuilder render(final StringBuilder buffer, final DocletTag tag)
    {
      final String reference = tag.getValue();
      if (StringUtils.isBlank(reference))
      {
        final JavaAnnotatedElement doc = tag.getContext();
        if (doc instanceof JavaField)
        {
          final JavaField fieldDoc = (JavaField) doc;
          appendConstantValue(buffer, fieldDoc);
        }
      }
      else
      {
        JavaAnnotatedElement doc = tag.getContext();
        if(doc instanceof JavaField)
        {
          doc = ((JavaField) doc).getDeclaringClass();
        }
  
        if (doc instanceof JavaClass)
        {
          final JavaClass classDoc = (JavaClass) doc;
          final String className = getClassName(reference);
          if (StringUtils.isNotBlank(className))
          {
            final JavaClass referencedClassDoc =
                classDoc.getJavaClassLibrary().getJavaClass(className);
            appendConstantValue(buffer, reference, referencedClassDoc);
          }
          else
          {
            appendConstantValue(buffer, reference, classDoc);
          }
        }
      }
      return buffer;
    }
  
    /**
     * Appends the constant value of the member within the given class referenced
     * by <code>reference</code>.
     *
     * @param buffer the buffer to append the constant value to (if any).
     * @param reference the reference to the member (required to be member of the
     *          given class.
     * @param classDoc the class to search for the referenced member.
    * @return the reference to the buffer for convenience.
    */
   private static StringBuilder appendConstantValue(final StringBuilder buffer,
       final String reference, final JavaClass classDoc)
   {
     final String member = getMemberName(reference);
     if (classDoc != null)
     {
       if (StringUtils.isNotBlank(member))
       {
         for (JavaField fieldDoc : classDoc.getFields())
         {
           if (member.equals(fieldDoc.getName()))
           {
             appendConstantValue(buffer, fieldDoc);
             return buffer;
           }
         }
         buffer.append("<code>").append(reference).append("</code>");
       }
     }
     else
     {
       buffer.append("<code>");
       if (StringUtils.isNotBlank(member))
       {
         buffer.append(reference.replace('#', '.'));
       }
       else
       {
         buffer.append(reference);
       }
       buffer.append("</code>");
     }
     return buffer;
   }
 
   /**
    * Appends the constant value of the field (if the field is a constant).
    *
    * @param buffer the buffer to append to.
    * @param fieldDoc the access to the constant value.
    */
   private static void appendConstantValue(final StringBuilder buffer,
       final JavaField fieldDoc)
   {
     final Object value = fieldDoc.getInitializationExpression();// constantValue();
     if (value != null)
     {
       buffer.append(value);
     }
   }
 
   /**
    * Returns the class (including package) part of the reference.
    *
    * @param reference the reference used in the value tag.
    * @return the class (including package) part of the reference.
    */
   private static String getClassName(final String reference)
   {
     final int index = reference.indexOf('#');
     if (index != -1)
     {
       final String className = reference.substring(0, index);
       return className;
     }
     return reference;
   }
 
   /**
    * Returns the member part of the reference.
    *
    * @param reference the reference used in the value tag.
    * @return the member part of the reference.
    */
   private static String getMemberName(final String reference)
   {
     final int index = reference.indexOf('#');
     if (index != -1 && index + 1 < reference.length())
     {
       final String memberName = reference.substring(index + 1);
       return memberName;
     }
     return null;
   }
 
   // --- object basics --------------------------------------------------------
 
 }