/*
    * Copyright (C) 2003-2010 eXo Platform SAS.
    *
    * This program is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Affero General Public License
    * as published by the Free Software Foundation; either version 3
    * of the License, or (at your option) any later version.
    *
    * This program 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 General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, see<http://www.gnu.org/licenses/>.
   */
  package org.exoplatform.social.core.processor;
  
  import java.util.List;
  import java.util.Map;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.exoplatform.container.xml.InitParams;
  import org.exoplatform.portal.config.UserPortalConfigService;
  import org.exoplatform.portal.webui.util.Util;
  import org.exoplatform.social.core.BaseActivityProcessorPlugin;
  import org.exoplatform.social.core.activity.model.ExoSocialActivity;
  import org.exoplatform.social.core.identity.model.Identity;
  import org.exoplatform.social.core.identity.provider.OrganizationIdentityProvider;
  import org.exoplatform.social.core.service.LinkProvider;
  
  /**
   * A processor that substitute @username expressions by a link on the user profile
   * @author <a href="mailto:patrice.lamarque@exoplatform.com">Patrice Lamarque</a>
   * @version $Revision$
   */
  public class MentionsProcessor extends BaseActivityProcessorPlugin {
  
    private static final Pattern pattern = Pattern.compile("@([^\\s]+)|@([^\\s]+)$");
  
    private UserPortalConfigService userPortalConfigService;
  
    public MentionsProcessor(InitParams params, UserPortalConfigService userPortalConfigService) {
      super(params);
      this.userPortalConfigService = userPortalConfigService;
    }
  
    public void processActivity(ExoSocialActivity activity) {
      if (activity != null) {
        String portalOwner = null;
        try{
          portalOwner = Util.getPortalRequestContext().getPortalOwner();
        } catch (Exception e){
          //default value for testing and social
          portalOwner = userPortalConfigService.getDefaultPortal();
        }
        activity.setTitle(substituteUsernames(portalOwner, activity.getTitle()));
        activity.setBody(substituteUsernames(portalOwner, activity.getBody()));
        Map<String, String> templateParams = activity.getTemplateParams();
        List<String> templateParamKeys = getTemplateParamKeysToFilter(activity);
        for(String key : templateParamKeys){
          templateParams.put(key, substituteUsernames(portalOwner, templateParams.get(key)));
        }
      }
    }
  
    /*
     * Substitute @username expressions by full user profile link
     */
    private String substituteUsernames(String portalOwner, String message) {
      if (message == null || message.trim().isEmpty()) {
        return message;
      }
      //
      Matcher matcher = pattern.matcher(message);
  
      // Replace all occurrences of pattern in input
      StringBuffer buf = new StringBuffer();
      while (matcher.find()) {
        // Get the match result
        String username = matcher.group().substring(1);
        if (username == null || username.isEmpty()) {
          continue;
        }
        Identity identity = LinkProvider.getIdentityManager().getOrCreateIdentity(OrganizationIdentityProvider.NAME, username, false);
        if (identity == null || identity.isDeleted() || !identity.isEnable()) {
          continue;
        }
        try {
          username = LinkProvider.getProfileLink(username, portalOwner);
        } catch (Exception e) {
          continue;
        }
        // Insert replacement
        if (username != null) {
          matcher.appendReplacement(buf, username);
        }
      }
     if (buf.length() > 0) {
       matcher.appendTail(buf);
       return buf.toString();
     }
     return message;
   }
 }