/*
    * $Id$
    *
    * 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.tiles.request.portlet;
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.io.Writer;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  
  import javax.portlet.PortletContext;
  import javax.portlet.PortletException;
  import javax.portlet.PortletRequestDispatcher;
  import javax.portlet.PortletResponse;
  import javax.portlet.PortletSession;
  
  import org.apache.tiles.request.AbstractClientRequest;
  import org.apache.tiles.request.ApplicationContext;
  import org.apache.tiles.request.attribute.Addable;
  import org.apache.tiles.request.collection.HeaderValuesMap;
  import org.apache.tiles.request.collection.ReadOnlyEnumerationMap;
  import org.apache.tiles.request.collection.ScopeMap;
  import org.apache.tiles.request.portlet.delegate.RequestDelegate;
  import org.apache.tiles.request.portlet.delegate.ResponseDelegate;
  import org.apache.tiles.request.portlet.extractor.HeaderExtractor;
  import org.apache.tiles.request.portlet.extractor.RequestScopeExtractor;
  import org.apache.tiles.request.portlet.extractor.SessionScopeExtractor;
  
  /**
   * Portlet-based TilesApplicationContext implementation.
   *
   * @version $Rev$ $Date$
   */
  public class PortletRequest extends AbstractClientRequest {
  
      /**
       * The native available scopes.
       */
      private static final List<String> SCOPES
              = Collections.unmodifiableList(Arrays.asList(REQUEST_SCOPE, "portletSession", "session", APPLICATION_SCOPE));
  
      /**
       * <p>The lazily instantiated <code>Map</code> of header name-value
       * combinations (immutable).</p>
       */
      private Map<String, String> header = null;
  
  
      /**
       * <p>The lazily instantiated <code>Map</code> of header name-value
       * combinations (write-only).</p>
       */
      private Addable<String> responseHeaders = null;
  
  
      /**
       * <p>The lazily instantitated <code>Map</code> of header name-values
       * combinations (immutable).</p>
       */
      private Map<String, String[]> headerValues = null;
  
      /**
       * The <code>PortletContext</code> for this application.
       */
      protected PortletContext context = null;
  
      /**
       * <p>The <code>PortletRequest</code> for this request.</p>
       */
      protected javax.portlet.PortletRequest request = null;
  
      /**
       * The delegate to get information about parameters.
       */
      protected RequestDelegate requestDelegate;
  
  
     /**
      * <p>The lazily instantiated <code>Map</code> of request scope
      * attributes.</p>
      */
     private Map<String, Object> requestScope = null;
 
 
     /**
      * <p>The <code>PortletResponse</code> for this request.</p>
      */
     protected PortletResponse response = null;
 
     /**
      * The delegate to get information from a response (output stream, writer, etc.).
      */
     protected ResponseDelegate responseDelegate;
 
 
     /**
      * <p>The lazily instantiated <code>Map</code> of session scope
      * attributes.</p>
      */
     private Map<String, Object> sessionScope = null;
 
     /**
      * <p>The lazily instantiated <code>Map</code> of portlet session scope
      * attributes.</p>
      */
     private Map<String, Object> portletSessionScope = null;
 
 
     /**
      * Creates a new instance of PortletTilesRequestContext.
      *
      * @param applicationContext The Tiles application context.
      * @param context The portlet context to use.
      * @param request The request object to use.
      * @param response The response object to use.
      * @param requestDelegate The request delegate.
      * @param responseDelegate The response delegate.
      */
     public PortletRequest(ApplicationContext applicationContext,
             PortletContext context, javax.portlet.PortletRequest request,
             PortletResponse response, RequestDelegate requestDelegate, ResponseDelegate responseDelegate) {
         super(applicationContext);
 
         // Save the specified Portlet API object references
         this.context = context;
         this.request = request;
         this.response = response;
         this.requestDelegate = requestDelegate;
         this.responseDelegate = responseDelegate;
     }
 
     /**
      * <p>Return the {@link PortletRequest} for this context.</p>
      *
      * @return The used portlet request.
      */
     public javax.portlet.PortletRequest getRequest() {
         return (this.request);
     }
 
     /**
      * <p>Return the {@link PortletResponse} for this context.</p>
      *
      * @return The used portlet response.
      */
     public PortletResponse getResponse() {
         return (this.response);
     }
 
     /**
      * Returns the portlet context.
      *
      * @return The portlet context.
      */
     public PortletContext getPortletContext() {
         return context;
     }
 
     /** {@inheritDoc} */
     public Map<String, String> getHeader() {
         if ((header == null) && (request != null)) {
             header = new ReadOnlyEnumerationMap<String>(new HeaderExtractor(request, null));
         }
         return (header);
     }
 
     /** {@inheritDoc} */
     public Addable<String> getResponseHeaders() {
         if ((responseHeaders == null) && (request != null)) {
             responseHeaders = new HeaderExtractor(null, response);
         }
         return (responseHeaders);
     }
 
     /** {@inheritDoc} */
     public Map<String, String[]> getHeaderValues() {
         if ((headerValues == null) && (request != null)) {
             headerValues = new HeaderValuesMap(new HeaderExtractor(request, response));
         }
         return (headerValues);
     }
 
     /** {@inheritDoc} */
     public Map<String, Object> getRequestScope() {
         if ((requestScope == null) && (request != null)) {
             requestScope = new ScopeMap(new RequestScopeExtractor(request));
         }
         return (requestScope);
     }
 
     /** {@inheritDoc} */
     public Map<String, Object> getSessionScope() {
         if ((sessionScope == null) && (request != null)) {
             sessionScope = new ScopeMap(new SessionScopeExtractor(request,
                     PortletSession.APPLICATION_SCOPE));
         }
         return (sessionScope);
     }
 
     /** {@inheritDoc} */
     public Map<String, Object> getPortletSessionScope() {
         if ((portletSessionScope == null) && (request != null)) {
             portletSessionScope = new ScopeMap(new SessionScopeExtractor(
                     request, PortletSession.APPLICATION_SCOPE));
         }
         return (portletSessionScope);
     }
 
     @Override
     public List<String> getAvailableScopes() {
         return SCOPES;
     }
 
     /** {@inheritDoc} */
     public Locale getRequestLocale() {
         return request.getLocale();
     }
 
     @Override
     public Map<String, String> getParam() {
         return requestDelegate.getParam();
     }
 
     @Override
     public Map<String, String[]> getParamValues() {
         return requestDelegate.getParamValues();
     }
 
     /** {@inheritDoc} */
     public boolean isUserInRole(String role) {
         return request.isUserInRole(role);
     }
 
     @Override
     public OutputStream getOutputStream() throws IOException {
         return responseDelegate.getOutputStream();
     }
 
     @Override
     public PrintWriter getPrintWriter() throws IOException {
         return responseDelegate.getPrintWriter();
     }
 
     @Override
     public Writer getWriter() throws IOException {
         return responseDelegate.getWriter();
     }
 
     @Override
     public boolean isResponseCommitted() {
         return responseDelegate.isResponseCommitted();
     }
 
     @Override
     public void setContentType(String contentType) {
         responseDelegate.setContentType(contentType);
     }
 
     /** {@inheritDoc} */
     public void doForward(String path) throws IOException {
         if (responseDelegate.isResponseCommitted()) {
             doInclude(path);
             return;
         }
 
         try {
             PortletRequestDispatcher rd = getPortletContext()
                     .getRequestDispatcher(path);
 
             if (rd == null) {
                 throw new IOException(
                         "No portlet request dispatcher returned for path '"
                                 + path + "'");
             }
 
             rd.forward(request, response);
         } catch (PortletException e) {
             throw new IOException("PortletException while including path '"
                     + path + "'.", e);
         }
     }
 
     /** {@inheritDoc} */
     public void doInclude(String path) throws IOException {
         try {
             PortletRequestDispatcher rd = getPortletContext()
                     .getRequestDispatcher(path);
 
             if (rd == null) {
                 throw new IOException(
                         "No portlet request dispatcher returned for path '"
                                 + path + "'");
             }
 
             rd.include(request, response);
         } catch (PortletException e) {
             throw new IOException("PortletException while including path '"
                     + path + "'.", e);
         }
     }
 
     @Override
     public Map<String, Object> getContext(String scope) {
         if(REQUEST_SCOPE.equals(scope)){
             return getRequestScope();
         }else if("session".equals(scope)){
             return getSessionScope();
         }else if("portletSession".equals(scope)){
             return getPortletSessionScope();
         }else if(APPLICATION_SCOPE.equals(scope)){
             return getApplicationScope();
         }
         throw new IllegalArgumentException(scope + " does not exist. Call getAvailableScopes() first to check.");
     }
 }