/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.apache.chemistry.opencmis.server.shared;
  
  import org.apache.chemistry.opencmis.commons.exceptions.CmisBaseException;
  import org.apache.chemistry.opencmis.commons.exceptions.CmisRuntimeException;
  import org.apache.chemistry.opencmis.commons.server.CallContext;
  import org.apache.chemistry.opencmis.commons.server.CmisService;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import java.io.Serializable;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  
  import java.util.HashMap;
  import java.util.Map;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  
  /**
   * Dispatcher for the AtomPub and Browser binding servlet.
   */
  public class Dispatcher implements Serializable
  {
      private static final long serialVersionUID = 1L;
      public static final String METHOD_GET = "GET";
      public static final String METHOD_POST = "POST";
      public static final String METHOD_PUT = "PUT";
      public static final String METHOD_DELETE = "DELETE";
      private static final Log LOG = LogFactory.getLog( Dispatcher.class.getName(  ) );
      private final boolean caseSensitive;
      private Map<String, Method> methodMap = new HashMap<String, Method>(  );
  
      public Dispatcher(  )
      {
          this( true );
      }
  
      public Dispatcher( boolean caseSensitive )
      {
          this.caseSensitive = caseSensitive;
      }
  
      /**
       * Connects a resource and HTTP method with a class and a class method.
       */
      public synchronized void addResource( String resource, String httpMethod, Class<?> clazz, String classmethod )
          throws NoSuchMethodException
      {
          Method m = clazz.getMethod( classmethod, CallContext.class, CmisService.class, String.class,
                  HttpServletRequest.class, HttpServletResponse.class );
  
          methodMap.put( getKey( resource, httpMethod ), m );
      }
  
      /**
       * Find the appropriate method an call it.
       *
       * @return
       * <code>true</code> if the method was found,
       * <code>false</code> otherwise.
       */
      public boolean dispatch( String resource, String httpMethod, CallContext context, CmisService service,
          String repositoryId, HttpServletRequest request, HttpServletResponse response )
      {
          Method m = methodMap.get( getKey( resource, httpMethod ) );
  
          if ( m == null )
          {
              return false;
          }
  
          if ( LOG.isDebugEnabled(  ) )
          {
              LOG.debug( repositoryId + " / " + resource + ", " + httpMethod + " -> " + m.getName(  ) );
          }
  
          try
         {
             m.invoke( null, context, service, repositoryId, request, response );
         }
         catch ( IllegalAccessException e )
         {
             throw new CmisRuntimeException( "Internal error!", e );
         }
         catch ( InvocationTargetException e )
         {
             if ( e.getCause(  ) instanceof CmisBaseException )
             {
                 throw (CmisBaseException) e.getCause(  );
             }
             else
             {
                 throw new CmisRuntimeException( e.getMessage(  ), e );
             }
         }
 
         return true;
     }
 
     /**
      * Generates a map key from a resource and an HTTP method.
      */
     private String getKey( String resource, String httpMethod )
     {
         String s = resource + "/" + httpMethod;
 
         return ( caseSensitive ? s : s.toUpperCase(  ) );
     }
 }