/* Copyright 2004, 2005 Acegi Technology Pty Limited
    *
    * 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 org.acegisecurity.intercept.web;
  
  import org.acegisecurity.ConfigAttributeDefinition;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.springframework.util.PathMatcher;
  import org.springframework.util.AntPathMatcher;
  
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Set;
  import java.util.Vector;
  
  
  /***
   * Maintains a <Code>List</code> of <code>ConfigAttributeDefinition</code>s
   * associated with different HTTP request URL Apache Ant path-based patterns.
   * 
   * <P>
   * Apache Ant path expressions are used to match a HTTP request URL against a
   * <code>ConfigAttributeDefinition</code>.
   * </p>
   * 
   * <p>
   * The order of registering the Ant paths using the {@link
   * #addSecureUrl(String, ConfigAttributeDefinition)} is very important. The
   * system will identify the <b>first</b>  matching path for a given HTTP URL.
   * It will not proceed to evaluate later paths if a match has already been
   * found. Accordingly, the most specific paths should be registered first,
   * with the most general paths registered last.
   * </p>
   * 
   * <P>
   * If no registered paths match the HTTP URL, <code>null</code> is returned.
   * </p>
   */
  public class PathBasedFilterInvocationDefinitionMap
      extends AbstractFilterInvocationDefinitionSource
      implements FilterInvocationDefinitionMap {
      //~ Static fields/initializers =============================================
  
      private static final Log logger = LogFactory.getLog(PathBasedFilterInvocationDefinitionMap.class);
  
      //~ Instance fields ========================================================
  
      private List requestMap = new Vector();
      private boolean convertUrlToLowercaseBeforeComparison = false;
      private PathMatcher pathMatcher = new AntPathMatcher();
  
      //~ Methods ================================================================
  
      public Iterator getConfigAttributeDefinitions() {
          Set set = new HashSet();
          Iterator iter = requestMap.iterator();
  
          while (iter.hasNext()) {
              EntryHolder entryHolder = (EntryHolder) iter.next();
              set.add(entryHolder.getConfigAttributeDefinition());
          }
  
          return set.iterator();
      }
  
      public void setConvertUrlToLowercaseBeforeComparison(
          boolean convertUrlToLowercaseBeforeComparison) {
          this.convertUrlToLowercaseBeforeComparison = convertUrlToLowercaseBeforeComparison;
      }
  
      public boolean isConvertUrlToLowercaseBeforeComparison() {
          return convertUrlToLowercaseBeforeComparison;
      }
  
      public int getMapSize() {
          return this.requestMap.size();
      }
  
      public void addSecureUrl(String antPath, ConfigAttributeDefinition attr) {
          requestMap.add(new EntryHolder(antPath, attr));
  
          if (logger.isDebugEnabled()) {
              logger.debug("Added Ant path: " + antPath + "; attributes: " + attr);
         }
     }
 
     public ConfigAttributeDefinition lookupAttributes(String url) {
         Iterator iter = requestMap.iterator();
 
         if (convertUrlToLowercaseBeforeComparison) {
             url = url.toLowerCase();
 
             if (logger.isDebugEnabled()) {
                 logger.debug("Converted URL to lowercase, from: '" + url
                     + "'; to: '" + url + "'");
             }
         }
 
         while (iter.hasNext()) {
             EntryHolder entryHolder = (EntryHolder) iter.next();
 
             boolean matched = pathMatcher.match(entryHolder.getAntPath(), url);
 
             if (logger.isDebugEnabled()) {
                 logger.debug("Candidate is: '" + url + "'; pattern is "
                     + entryHolder.getAntPath() + "; matched=" + matched);
             }
 
             if (matched) {
                 return entryHolder.getConfigAttributeDefinition();
             }
         }
 
         return null;
     }
 
     //~ Inner Classes ==========================================================
 
     protected class EntryHolder {
         private ConfigAttributeDefinition configAttributeDefinition;
         private String antPath;
 
         public EntryHolder(String antPath, ConfigAttributeDefinition attr) {
             this.antPath = antPath;
             this.configAttributeDefinition = attr;
         }
 
         protected EntryHolder() {
             throw new IllegalArgumentException("Cannot use default constructor");
         }
 
         public String getAntPath() {
             return antPath;
         }
 
         public ConfigAttributeDefinition getConfigAttributeDefinition() {
             return configAttributeDefinition;
         }
     }
 }