MonoRail/Castle.MonoRail.ActiveRecordSupport/Pagination/ARPagination.cs

   1  // Copyright 2004-2008 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.MonoRail.ActiveRecordSupport.Pagination
  16 {
  17         using System;
  18         using System.Collections;
  19         using System.Text.RegularExpressions;
  20
  21         using Castle.ActiveRecord.Queries;
  22         using Castle.MonoRail.Framework;
  23         using Castle.MonoRail.Framework.Helpers;
  24
  25         using NHibernate.Criterion;
  26
  27         /// <summary>
  28         /// Pendent
  29         /// </summary>
  30         public class ARPaginationHelper : AbstractHelper
  31         {
  32                 /// <summary>
  33                 /// Paginates using an <see cref="ARPaginableSimpleQuery"/>
  34                 /// </summary>
  35                 public static IPaginatedPage CreatePagination(int pageSize, Type targetType, string hql, params object[] parameters)
  36                 {
  37                         IARPaginableDataSource criteria = new ARPaginableSimpleQuery(targetType, hql, parameters);
  38                         return CreatePagination(pageSize, criteria);
  39                 }
  40
  41                 /// <summary>
  42                 /// Paginates using an <see cref="ARPaginableCriteria"/>
  43                 /// </summary>
  44                 public static IPaginatedPage CreatePagination(int pageSize, Type targetType, params Order[] orders)
  45                 {
  46                         return CreatePagination(pageSize, targetType, orders, null);
  47                 }
  48
  49                 /// <summary>
  50                 /// Paginates using an <see cref="ARPaginableCriteria"/>
  51                 /// </summary>
  52                 public static IPaginatedPage CreatePagination(int pageSize, Type targetType, Order[] orders, params ICriterion[] criterions)
  53                 {
  54                         IARPaginableDataSource criteria = new ARPaginableCriteria(targetType, orders, criterions);
  55                         return CreatePagination(pageSize, criteria);
  56                 }
  57
  58                 /// <summary>
  59                 /// Paginates using an <see cref="ARPaginableCriteria"/>
  60                 /// </summary>
  61                 public static IPaginatedPage CreatePagination(int pageSize, Type targetType, DetachedCriteria detachedCriteria)
  62                 {
  63                         IARPaginableDataSource criteria = new ARPaginableCriteria(targetType, detachedCriteria);
  64                         return CreatePagination(pageSize, criteria);
  65                 }
  66
  67                 /// <summary>
  68                 /// Paginates using the specified <see cref="IARPaginableDataSource"/>.
  69                 /// </summary>
  70                 public static IPaginatedPage CreatePagination(int pageSize, IARPaginableDataSource criteria)
  71                 {
  72                         return new ARPager(pageSize, criteria, ObtainCurrentPage());
  73                 }
  74
  75                 private static int ObtainCurrentPage()
  76                 {
  77                         // Tight coupling that makes difficult to test. Review this!
  78                         String page = MonoRailHttpHandlerFactory.CurrentEngineContext.Request.Params["page"];
  79                         return page == null || Regex.IsMatch(page, "\\D")
  80                                 ? 1 : Convert.ToInt32(page);
  81                 }
  82         }
  83
  84         /// <summary>
  85         /// Pendent
  86         /// </summary>
  87         public class ARPager : AbstractPage
  88         {
  89                 private IEnumerable enumerable;
  90
  91                 public ARPager(int pageSize, IARPaginableDataSource source, int currentPage)
  92                 {
  93                         int count = source.ObtainCount();
  94                         int startIndex = (pageSize * currentPage) - pageSize;
  95                         int endIndex = Math.Min(startIndex + pageSize, count);
  96
  97                         enumerable = source.Paginate(pageSize, currentPage);
  98
  99                         CalculatePaginationInfo(startIndex, endIndex, count, pageSize, currentPage);
 100                 }
 101
 102                 public override IEnumerator GetEnumerator()
 103                 {
 104                         return enumerable.GetEnumerator();
 105                 }
 106         }
 107 }