feat: replace CategoryMultiSelectCombo with MudSelect for category selection; implement category loading and flattening logic

src/BackOffice/Pages/DiscountShop/Components/ProductFormDialog.razor

@@ -3,7 +3,6 @@
 @using Microsoft.AspNetCore.Components.Forms
 @using Tizzani.MudBlazor.HtmlEditor
 @using BackOffice.Common.BaseComponents
-@using BackOffice.Pages.AutoComplete
 @inject ISnackbar Snackbar
 
 <MudDialog>
@@ -112,13 +111,22 @@
 
                 <MudStack Spacing="1">
                     <MudText Typo="Typo.subtitle2">دسته‌بندی‌ها</MudText>
-                    <CategoryMultiSelectCombo @bind-SelectedIds="_selectedCategoryIds"
+                    <MudSelect @bind-SelectedValues="_selectedCategoryIds" 
-                                              Label="انتخاب دسته‌بندی‌ها"
+                               Label="انتخاب دسته‌بندی‌ها" 
-                                              Disabled="_loading" />
+                               Variant="Variant.Outlined"
-                    @if (_selectedCategoryIds?.Count > 0)
+                               Margin="Margin.Dense"
+                               MultiSelection="true"
+                               Disabled="_loading"
+                               T="long">
+                        @foreach (var category in _categories)
+                        {
+                            <MudSelectItem Value="@category.Id">@category.Title</MudSelectItem>
+                        }
+                    </MudSelect>
+                    @if (_selectedCategoryIds?.Any() == true)
                     {
                         <MudText Typo="Typo.caption">
-                            تعداد دسته‌بندی‌های انتخاب‌شده: @_selectedCategoryIds.Count
+                            تعداد دسته‌بندی‌های انتخاب‌شده: @_selectedCategoryIds.Count()
                         </MudText>
                     }
                 </MudStack>
@@ -166,16 +174,58 @@
     private IBrowserFile? _thumbnailImageFile;
     private readonly long _maxAllowedSize = (1024 * 1024) * 5;
     private string? _mainImagePreview;
-    private List<long> _selectedCategoryIds = new();
+    private IEnumerable<long> _selectedCategoryIds = new List<long>();
+    private List<DiscountCategoryDto> _categories = new();
 
     protected override async Task OnInitializedAsync()
     {
+        await LoadCategories();
+        
         if (Model.CategoryIds?.Any() == true)
         {
             _selectedCategoryIds = Model.CategoryIds;
         }
     }
 
+    private async Task LoadCategories()
+    {
+        try
+        {
+            var tree = await CategoryService.GetCategoriesAsync(isActive: true);
+            _categories = FlattenCategories(tree);
+        }
+        catch (Exception ex)
+        {
+            Snackbar.Add($"خطا در بارگذاری دسته‌بندی‌ها: {ex.Message}", Severity.Error);
+        }
+    }
+
+    private List<DiscountCategoryDto> FlattenCategories(List<DiscountCategoryDto> categories, string prefix = "")
+    {
+        var result = new List<DiscountCategoryDto>();
+        foreach (var category in categories)
+        {
+            var catCopy = new DiscountCategoryDto
+            {
+                Id = category.Id,
+                Title = prefix + category.Title,
+                ParentCategoryId = category.ParentCategoryId
+            };
+            result.Add(catCopy);
+            
+            if (category.Children.Any())
+            {
+                result.AddRange(FlattenCategories(category.Children.ToList(), prefix + "  "));
+            }
+        }
+        return result;
+    }
+
+    private string GetCategoryPath(DiscountCategoryDto category)
+    {
+        return category.Title;
+    }
+
     private async Task OnMainImageSelected(IBrowserFile? file)
     {
         _mainImageFile = file;