/*
    * Copyright (C) 2003-2008 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.services.wcm.publication;
  
  import org.exoplatform.commons.exception.ExoMessageException;
  import org.exoplatform.commons.utils.PageList;
  import org.exoplatform.services.wcm.utils.WCMCoreUtils;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Created by The eXo Platform SAS
   * Author : Hoa Pham
   * hoa.phamvu@exoplatform.com
   * Oct 17, 2008
   */
  @SuppressWarnings({ "deprecation", "unchecked" })
  public class PaginatedResultIterator extends PageList {
  
    /** The nodes. */
    protected Result result;
  
    /**
     * Instantiates a new paginated node iterator.
     *
     * @param pageSize the page size
     */
    public PaginatedResultIterator(int pageSize) {
      super(pageSize);
    }
  
    public PaginatedResultIterator(Result result, int pageSize) {
       super(pageSize);
       this.result = result;
       this.setAvailablePage((int)result.getNumTotal());
       this.currentListPage_ = null;
    }
  
    /* (non-Javadoc)
     * @see org.exoplatform.commons.utils.PageList#populateCurrentPage(int)
     */
    protected void populateCurrentPage(int page) throws Exception {
      if(page == currentPage_) {
        if(currentListPage_ != null)
          return;
      }
      currentListPage_ = new ArrayList();
  
      WCMComposer composer = WCMCoreUtils.getService(WCMComposer.class);
      result.getFiltersDescriber().put(WCMComposer.FILTER_LIMIT, ""+this.getPageSize());
      result.getFiltersDescriber().put(WCMComposer.FILTER_OFFSET, ""+(this.getPageSize()*(page-1)));
      result.getFiltersDescriber().put(WCMComposer.FILTER_TOTAL, ""+this.result.getNumTotal());
      result = composer.getPaginatedContents(result.getNodeLocationDescriber(),
                                             result.getFiltersDescriber(),
                                             WCMCoreUtils.getUserSessionProvider());
  
      currentListPage_ = result.getNodes();
  
      currentPage_ = page;
    }
  
    /**
     * Retrieve the total pages.
     * 
     * @return the total pages
     */
    public int getTotalPages() { return getAvailablePage(); }  
  
    /**
     * Retrieve the nodes per page.
     * 
     * @return the nodes per page
     */
    public int getNodesPerPage() { return getPageSize(); }    
  
    /**
     * Retrieve the total nodes.
     * 
     * @return the total nodes
     */
    public long getTotalNodes() {
      return result.getNumTotal();
    }
  
   /**
    * Retrieve the nodes of current page.
    * 
    * @return the current page data
    * 
    * @throws Exception the exception
    */
   public List getCurrentPageData() throws Exception {
     return currentPage();
   }
   
   /* (non-Javadoc)
    * @see org.exoplatform.commons.utils.PageList#getPage(int)
    */
   public List getPage(int page) throws Exception {
     if (page < 1 || page > availablePage_) {
       Object[] args = { Integer.toString(page), Integer.toString(availablePage_) };
       throw new ExoMessageException("PageList.page-out-of-range", args);
     }
     populateCurrentPage(page);
     while (currentListPage_ != null && currentListPage_.size() == 0 && page > 1) {
       page--;
       result.setNumTotal(page * this.getPageSize());
       populateCurrentPage(page);
       availablePage_ = page;
     }
 
     return currentListPage_;
     
   }
 
   /**
    * Change page.
    * 
    * @param page the page
    * 
    * @throws Exception the exception
    */
   public void changePage(int page) throws Exception {
     populateCurrentPage(page);
   }
 
   /* (non-Javadoc)
    * @see org.exoplatform.commons.utils.PageList#getAll()
    */
   public List getAll() throws Exception {
     throw new UnsupportedOperationException();
   }
 }