MultiCriteriaSortingOptions implemented

src/Framework/Core/Controls/GenericGridViewDataSet.cs

@@ -92,5 +92,26 @@ public void RequestRefresh()
         {
             IsRefreshRequired = true;
         }
+
+        /// <summary>
+        /// Applies the options from the specified <see cref="GridViewDataSetOptions{TFilteringOptions, TSortingOptions, TPagingOptions}" /> to this instance.
+        /// </summary>
+        public void ApplyOptions(GridViewDataSetOptions<TFilteringOptions, TSortingOptions, TPagingOptions> options)
+        {
+            if (options.FilteringOptions != null)
+            {
+                FilteringOptions = options.FilteringOptions;
+            }
+
+            if (options.SortingOptions != null)
+            {
+                SortingOptions = options.SortingOptions;
+            }
+
+            if (options.PagingOptions != null)
+            {
+                PagingOptions = options.PagingOptions;
+            }
+        }
     }
 }

src/Framework/Core/Controls/GridViewDataSetExtensions.cs

@@ -26,9 +26,9 @@ public static void LoadFromQueryable<T>(this IGridViewDataSet<T> dataSet, IQuery
             var paged = pagingOptions.ApplyToQueryable(sorted);
             dataSet.Items = paged.ToList();
 
-            if (pagingOptions is IPagingTotalItemsCountCapability pagingTotalItemsCount)
+            if (pagingOptions is IPagingOptionsLoadingPostProcessor pagingOptionsLoadingPostProcessor)
             {
-                pagingTotalItemsCount.TotalItemsCount = filtered.Count();
+                pagingOptionsLoadingPostProcessor.ProcessLoadedItems(filtered, dataSet.Items);
             }
 
             dataSet.IsRefreshRequired = false;
@@ -63,5 +63,6 @@ public static void GoToPageAndRefresh(this IPageableGridViewDataSet<IPagingPageI
             dataSet.PagingOptions.GoToPage(pageIndex);
             (dataSet as IRefreshableGridViewDataSet)?.RequestRefresh();
         }
+
     }
 }

src/Framework/Core/Controls/IFilterableGridViewDataSet.cs

@@ -19,4 +19,4 @@ public interface IFilterableGridViewDataSet : IBaseGridViewDataSet
         /// </summary>
         IFilteringOptions FilteringOptions { get; }
     }
-}
+}

src/Framework/Core/Controls/Options/GridViewDataSetOptions.cs

@@ -0,0 +1,18 @@
+namespace DotVVM.Framework.Controls
+{
+    public class GridViewDataSetOptions<TFilteringOptions, TSortingOptions, TPagingOptions>
+        where TFilteringOptions : IFilteringOptions
+        where TSortingOptions : ISortingOptions
+        where TPagingOptions : IPagingOptions
+    {
+        public TFilteringOptions? FilteringOptions { get; set; } = default;
+
+        public TSortingOptions? SortingOptions { get; set; } = default;
+
+        public TPagingOptions? PagingOptions { get; set; } = default;
+    }
+
+    public class GridViewDataSetOptions : GridViewDataSetOptions<NoFilteringOptions, SortingOptions, PagingOptions>
+    {
+    }
+}

src/Framework/Core/Controls/Options/IPagingOptionsLoadingPostProcessor.cs

@@ -0,0 +1,9 @@
+using System.Collections.Generic;
+using System.Linq;
+
+namespace DotVVM.Framework.Controls;
+
+public interface IPagingOptionsLoadingPostProcessor
+{
+    void ProcessLoadedItems<T>(IQueryable<T> filteredQueryable, IList<T> items);
+}

src/Framework/Core/Controls/Options/MultiCriteriaSortingOptions.cs

@@ -0,0 +1,77 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace DotVVM.Framework.Controls;
+
+public class MultiCriteriaSortingOptions : SortingOptions, ISortingMultipleCriteriaCapability
+{
+    public IList<SortCriterion> Criteria { get; set; } = new List<SortCriterion>();
+
+    public int MaxSortCriteriaCount { get; set; } = 3;
+
+    public override IQueryable<T> ApplyToQueryable<T>(IQueryable<T> queryable)
+    {
+        foreach (var criterion in Criteria.Reverse())
+        {
+            queryable = SortingImplementation.ApplySortingToQueryable(queryable, criterion.SortExpression, criterion.SortDescending);
+        }
+
+        return base.ApplyToQueryable(queryable);
+    }
+
+    public override void SetSortExpression(string? sortExpression)
+    {
+        if (SortExpression == null)
+        {
+            SortExpression = sortExpression;
+            SortDescending = false;
+        }
+        else if (sortExpression == SortExpression)
+        {
+            if (!SortDescending)
+            {
+                SortDescending = true;
+            }
+            else if (Criteria.Any())
+            {
+                SortExpression = Criteria[0].SortExpression;
+                SortDescending = Criteria[0].SortDescending;
+                Criteria.RemoveAt(0);
+            }
+            else
+            {
+                SortExpression = null;
+                SortDescending = false;
+            }
+        }
+        else
+        {
+            var index = Criteria.ToList().FindIndex(c => c.SortExpression == sortExpression);
+            if (index >= 0)
+            {
+                if (!Criteria[index].SortDescending)
+                {
+                    Criteria[index].SortDescending = true;
+                }
+                else
+                {
+                    Criteria.RemoveAt(index);
+                }
+            }
+            else
+            {
+                if (Criteria.Count < MaxSortCriteriaCount - 1)
+                {
+                    Criteria.Add(new SortCriterion() { SortExpression = sortExpression });
+                }
+                else
+                {
+                    SortExpression = sortExpression;
+                    SortDescending = false;
+                    Criteria.Clear();
+                }
+            }
+        }
+    }
+}

src/Framework/Core/Controls/Options/PagingOptions.cs

@@ -8,7 +8,7 @@ namespace DotVVM.Framework.Controls
     /// <summary>
     /// Represents settings for paging.
     /// </summary>
-    public class PagingOptions : IPagingOptions, IPagingFirstPageCapability, IPagingLastPageCapability, IPagingPreviousPageCapability, IPagingNextPageCapability, IPagingPageIndexCapability, IPagingPageSizeCapability, IPagingTotalItemsCountCapability, IApplyToQueryable
+    public class PagingOptions : IPagingOptions, IPagingFirstPageCapability, IPagingLastPageCapability, IPagingPreviousPageCapability, IPagingNextPageCapability, IPagingPageIndexCapability, IPagingPageSizeCapability, IPagingTotalItemsCountCapability, IApplyToQueryable, IPagingOptionsLoadingPostProcessor
     {
         /// <summary>
         /// Gets or sets the object that provides a list of page indexes near the current page.
@@ -114,5 +114,10 @@ public IQueryable<T> ApplyToQueryable<T>(IQueryable<T> queryable)
         {
             return PagingImplementation.ApplyPagingToQueryable(queryable, this);
         }
+
+        public void ProcessLoadedItems<T>(IQueryable<T> filteredQueryable, IList<T> items)
+        {
+            TotalItemsCount = filteredQueryable.Count();
+        }
     }
 }

src/Framework/Core/Controls/Options/SortingOptions.cs

@@ -50,9 +50,9 @@ public virtual void SetSortExpression(string? sortExpression)
         /// <summary>
         /// Applies the sorting options to the specified IQueryable expression.
         /// </summary>
-        public IQueryable<T> ApplyToQueryable<T>(IQueryable<T> queryable)
+        public virtual IQueryable<T> ApplyToQueryable<T>(IQueryable<T> queryable)
         {
-            return SortingImplementation.ApplySortingToQueryable(queryable, this);
+            return SortingImplementation.ApplySortingToQueryable(queryable, SortExpression, SortDescending);
         }
     }
 }

src/Framework/Core/Controls/SortingImplementation.cs

@@ -14,16 +14,16 @@ public static class SortingImplementation
         /// of items is retrieved.
         /// </summary>
         /// <param name="queryable">The <see cref="IQueryable{T}" /> to modify.</param>
-        public static IQueryable<T> ApplySortingToQueryable<T>(IQueryable<T> queryable, ISortingSingleCriterionCapability options)
+        public static IQueryable<T> ApplySortingToQueryable<T>(IQueryable<T> queryable, string? sortExpression, bool sortDescending)
         {
-            if (options.SortExpression == null)
+            if (sortExpression == null)
             {
                 return queryable;
             }
 
             var parameterExpression = Expression.Parameter(typeof(T), "p");
             Expression sortByExpression = parameterExpression;
-            foreach (var prop in (options.SortExpression ?? "").Split(new[] { '.' }, StringSplitOptions.RemoveEmptyEntries))
+            foreach (var prop in sortExpression.Split(new[] { '.' }, StringSplitOptions.RemoveEmptyEntries))
             {
                 var property = sortByExpression.Type.GetProperty(prop);
                 if (property == null)
@@ -46,7 +46,7 @@ public static IQueryable<T> ApplySortingToQueryable<T>(IQueryable<T> queryable,
                 return queryable;
             }
             var lambdaExpression = Expression.Lambda(sortByExpression, parameterExpression);
-            var methodCallExpression = Expression.Call(typeof(Queryable), GetSortingMethodName(options.SortDescending),
+            var methodCallExpression = Expression.Call(typeof(Queryable), GetSortingMethodName(sortDescending),
                 new[] { parameterExpression.Type, sortByExpression.Type },
                 queryable.Expression,
                 Expression.Quote(lambdaExpression));