/**
    * This file Copyright (c) 2003-2017 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.module.forum.frontend;
  
  import info.magnolia.cms.core.Content;
  import info.magnolia.cms.security.SecurityUtil;
  import info.magnolia.context.MgnlContext;
  import info.magnolia.link.LinkUtil;
  import info.magnolia.module.forum.ForumManager;
  
  import java.io.IOException;
  
  import javax.jcr.RepositoryException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.lang3.StringUtils;
  
  /**
   * Custom page handler for Forum.
   * 
   * @author gjoseph
   */
  public class ForumController {
      private final ForumManager forumManager;
      private final HttpServletRequest request;
      private final HttpServletResponse response;
  
      /** for tests and when we have ioc! */
      protected ForumController(String name, HttpServletRequest request, HttpServletResponse response, ForumManager forumManager) {
          this.request = request;
          this.response = response;
          this.forumManager = forumManager;
      }
  
      public ForumController(String name, HttpServletRequest request, HttpServletResponse response) {
          this(name, request, response, ForumManager.Factory.getInstance());
      }
  
      public String getCommand() {
          return mandatoryParam("command");
      }
  
      /**
       * executes the method named after the return value of getCommand().
       */
      public String execute(String command) {
          // TODO : maybe review, this will try to find a command in the catalog first,
          // while we'd really like to just use super.super.execute()
          throw new UnsupportedOperationException();
      }
  
      /**
       * This implementation does a redirect:
       * - to the view parameter, using it as a url.
       * - to the referer if the view argument was null. (i.e. if the command method was void or returned null explicitely)
       */
      public void renderHtml(final String view) throws IOException {
          final String targetUrl;
          if (view == null) {
              targetUrl = request.getHeader("referer");
          } else {
              targetUrl = view;
          }
  
          mandatory(targetUrl, "referer or target view");
          response.sendRedirect(targetUrl);
      }
 
     public void init() {
         throw new UnsupportedOperationException();
     }
 
     // ---------------- commands - these methods are called through reflection --------------------
     // the regular return value for these should be the name of the "view" to show, but we're reaching the limits here
     // and return an absolute url instead. renderHtml() knows about this.
     public String createThread() throws RepositoryException {
         final String forumId = mandatoryParam("forumId");
         final String threadTitle = mandatoryParam("threadTitle");
         final String messageText = mandatoryParam("messageText");
         Content newThread;
 
         if (!SecurityUtil.isAnonymous()) {
             final String userId = getUserId();
             newThread = forumManager.createThread(forumId, threadTitle, messageText, userId, false);
         } else {
             final String anonymousUsername = mandatoryParam("anonymousUsername");
             newThread = forumManager.createThread(forumId, threadTitle, messageText, anonymousUsername, true);
         }
 
         // TODO : maybe the construction of the url should be left to the user/dialog and we should just replace parameters like {0}
         // TODO : use/improve the link api to handle parameters
         final String targetPageUUID = mandatoryParam("targetPage");
         final String targetPage = LinkUtil.createAbsoluteLink("website", targetPageUUID);
         return targetPage + "?threadId=" + newThread.getUUID() + "&forumId=" + forumId;
     }
 
     public String replyToThread() throws RepositoryException {
         final String threadId = mandatoryParam("threadId");
         final String messageTitle = param("messageTitle");
         final String messageText = mandatoryParam("messageText");
         final String inReplyTo = param("inReplyTo");
 
         if (!SecurityUtil.isAnonymous()) {
             final String userId = getUserId();
             forumManager.replyToThread(threadId, inReplyTo, messageTitle, messageText, userId, false);
         } else {
             final String anonymousUsername = mandatoryParam("anonymousUsername");
             forumManager.replyToThread(threadId, inReplyTo, messageTitle, messageText, anonymousUsername, true);
         }
 
         final String targetPageUUID = param("targetPage");
         if (StringUtils.isNotEmpty(targetPageUUID)) {
             final String targetPage = LinkUtil.createAbsoluteLink("website", targetPageUUID);
             return targetPage + "?threadId=" + threadId;
         } else {
             return null;
         }
     }
 
     // TODO : use UUID ?
     protected String getUserId() {
         return MgnlContext.getUser().getName();
     }
 
     private String param(String paramName) {
         final String value = request.getParameter(paramName);
         return StringUtils.stripToNull(value);
     }
 
     private String mandatoryParam(String paramName) {
         final String value = param(paramName);
         mandatory(value, paramName);
         return value;
     }
 
     private void mandatory(String s, String desc) {
         if (StringUtils.isEmpty(s)) {
             throw new RuntimeException(desc + " is mandatory and is missing from the request.");
         }
     }
 }