/*
 * Copyright (C) 2010 eXo Platform SAS.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.exoplatform.services.portletcache;

import java.io.IOException;
import java.io.OutputStream;
import java.util.Locale;
import java.util.Map;

import javax.portlet.ActionRequest;
import javax.portlet.ActionResponse;
import javax.portlet.EventRequest;
import javax.portlet.EventResponse;
import javax.portlet.PortletException;
import javax.portlet.PortletMode;
import javax.portlet.RenderRequest;
import javax.portlet.RenderResponse;
import javax.portlet.filter.ActionFilter;
import javax.portlet.filter.EventFilter;
import javax.portlet.filter.FilterChain;
import javax.portlet.filter.FilterConfig;
import javax.portlet.filter.PortletFilter;
import javax.portlet.filter.RenderFilter;

import org.exoplatform.container.PortalContainer;
import org.exoplatform.portal.application.PortalRequestContext;
import org.exoplatform.portal.webui.util.Util;
import org.exoplatform.portal.webui.workspace.UIPortalApplication;

/**
 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
 * @version $Revision$
 */
public class PortletCacheFilter implements PortletFilter, ActionFilter, RenderFilter, EventFilter
{

  private static final String EXO_CACHE = "exo.cache";
  private static final String TRUE = "true";
  private static final String FALSE = "false";
  private static final String SHARED_CACHE = "sharedCache";
  private static final String TURN_ON_QUICK_EDIT = "turnOnQuickEdit";
  private static final String NO_CACHE = "nocache";
  
  public PortletCacheFilter()
  {
  }

  public void init(FilterConfig cfg) throws PortletException
  {
  }

  public void destroy()
  {
  }

  public void doFilter(ActionRequest req, ActionResponse resp, FilterChain chain) throws IOException, PortletException
  {
    chain.doFilter(req, resp);
  }

  public void doFilter(EventRequest req, EventResponse resp, FilterChain chain) throws IOException, PortletException
  {
    chain.doFilter(req, resp);
  }
  /**
   * @return true if current context is PortalEditMode
   * @author vinh_nguyen
   */
  private boolean isPortalEditMode() {
    return Util.getUIPortalApplication().getModeState() != UIPortalApplication.NORMAL_MODE;
  }
  public void doFilter(RenderRequest req, RenderResponse resp, FilterChain chain) throws IOException, PortletException
  {
    String exoCacheUsageRequestParam = Util.getPortalRequestContext().getRequestParameter(EXO_CACHE);
    PortalRequestContext ctx = (PortalRequestContext)PortalRequestContext.getCurrentInstance();
    Boolean quickEdit = (Boolean) ctx.getRequest().getSession().getAttribute(TURN_ON_QUICK_EDIT);
    if (quickEdit==null) quickEdit=false;
    Boolean sharedCache = TRUE.equals(req.getPreferences().getValue(SHARED_CACHE, FALSE));
    PortletMode portletMode = req.getPortletMode();
    
    if (!NO_CACHE.equals(exoCacheUsageRequestParam) && sharedCache &&
        (req.getRemoteUser() == null || (!quickEdit && !isPortalEditMode())) &&
        !PortletMode.EDIT.equals(portletMode)) {
      Map<String, String[]> query = (Map<String, String[]>)ctx.getRequest().getParameterMap();
      //
      Locale locale = ctx.getLocale();
      //
      WindowKey key = new WindowKey(
          req.getWindowID(),
          req.getWindowState(),
          req.getPortletMode(),
          locale,
          req.getParameterMap(),
          query);

      //
      FragmentCacheService service = (FragmentCacheService)PortalContainer.getInstance().
          getComponentInstanceOfType(FragmentCacheService.class);
      MarkupFragment value = service.cache.get(new PortletRenderContext(req, resp, chain), key);
      OutputStream out = resp.getPortletOutputStream();
      out.write(value.data);
      out.close();
    }
    else
    {
      chain.doFilter(req, resp);
    }
  }
}

