/*
    * Copyright 2004 Jeff Johnston
    *
    * Licensed 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.extremecomponents.table.model;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.extremecomponents.table.bean.TableSection;
  import org.extremecomponents.table.cell.Cell;
  import org.extremecomponents.table.cell.PageCell;
  
  
  
  /***
   * Keep track of the page information
   *
   * @author Jeff Johnston
   */
  public class PageHandler
  {
  	private static Log logger = LogFactory.getLog(PageHandler.class);
  	public final static String FIRST = "First";
  	public final static String LAST = "Last";
  	public final static String PREV = "Prev";
  	public final static String NEXT = "Next";
  	public final static String LAST_PAGE = "lastPage";
  	public final static String FIRST_PAGE = "firstPage";
  	public final static String PREV_PAGE = "prevPage";
  	public final static String NEXT_PAGE = "nextPage";
  	
  	private TableModel model;
  	
  	public PageHandler(TableModel model)
  	{
  		this.model = model;
  	}
  
  	/***
  	 * Build up the pagination cells.
  	 */
  	public List getPagination(TableModel model)
  	{
  		List pagination = new ArrayList();
  
  		if (!model.getTable().doPagination())
  		{
  			return pagination;
  		}
  
  		TableSection tableSection = model.getTableSection();
  
  		int maxRows = Integer.parseInt(model.getTable().getMaxRows());
  
  		if (maxRows == 0)
  		{
  			maxRows = tableSection.getTotalRows();
  		}
  
  		int totalRows = tableSection.getTotalRows();
  
  		int sections = 1;
  
  		if (maxRows != 0)
  		{
  			sections = totalRows / maxRows; //split the sections up
  		}
  
  		if ((maxRows != 0) && ((totalRows % maxRows) > 0)) //have a few straglers
  		{
  			sections++;
  		}
  
  		if (sections > 1)
  		{
  			buildPagination(model, pagination, tableSection, sections);
  		}
  
  		return pagination;
  	}
  
  	private void buildPagination(TableModel model, List pagination, TableSection tableSections, int sections)
  	{
  		int page = tableSections.getPage();
  
 		//FIRST
 		int startFirst = 1;
 
 		if (page == 1)
 		{
 			startFirst = -1;
 		}
 
 		pagination.add(buildPaginationCell(model, FIRST, startFirst, false));
 
 		//PREV
 		int startPrev = page - 1;
 
 		if (page == 1)
 		{
 			startPrev = -1;
 		}
 
 		pagination.add(buildPaginationCell(model, PREV, startPrev, false));
 
 		//start of body
 		int begin = 1;
 		int end = sections;
 
 		if (sections > 9)
 		{
 			end = 9;
 		}
 
 		if ((sections > 9) && (page > 5)) //put in the middle if have more than 9 sections and not in the middle
 		{
 			begin = page - 4;
 			end = page + 4;
 
 			if (end > sections)
 			{
 				begin = sections - 8;
 				end = sections;
 			}
 		}
 
 		//now go through the body
 		for (int i = begin; i <= end; i++)
 		{
 			if (i == page)
 			{
 				pagination.add(buildPaginationCell(model, "" + i, i, true));
 			}
 			else
 			{
 				pagination.add(buildPaginationCell(model, "" + i, i, false));
 			}
 		}
 
 		//end of body
 		//NEXT
 		int startNext = page + 1;
 
 		if (page == sections)
 		{
 			startNext = -1;
 		}
 
 		pagination.add(buildPaginationCell(model, NEXT, startNext, false));
 
 		//Last
 		int startLast = sections;
 
 		if (page == sections)
 		{
 			startLast = -1;
 		}
 
 		pagination.add(buildPaginationCell(model, LAST, startLast, false));
 	}
 
 	public String buildPaginationCell(TableModel model, String name, int page, boolean selected)
 	{
 		Cell cell = model.getCachedCell(PageCell.class);
 		cell.init(model, null, null);
 		((PageCell)cell).initCustom(name, page, selected); //not the normal case...
 		String html = cell.html();
 		cell.destroy();
 		return html;
 	}
 }