Migliorata sincronizzazione dei dati

salesbook.Shared/Core/Services/PreloadService.cs

@@ -0,0 +1,55 @@
+using salesbook.Shared.Core.Dto;
+using salesbook.Shared.Core.Dto.Contact;
+using salesbook.Shared.Core.Dto.PageState;
+using salesbook.Shared.Core.Dto.Users;
+using salesbook.Shared.Core.Interface;
+
+namespace salesbook.Shared.Core.Services;
+
+public class PreloadService(IManageDataService manageData, UserListState userState)
+{
+    public async Task PreloadUsersAsync()
+    {
+        if (userState.IsLoaded || userState.IsLoading)
+            return;
+
+        userState.IsLoading = true;
+
+        var users = await manageData.GetContact(new WhereCondContact { FlagStato = "A" });
+
+        var sorted = users
+            .Where(u => !string.IsNullOrWhiteSpace(u.RagSoc))
+            .OrderBy(u => char.IsLetter(char.ToUpper(u.RagSoc[0])) ? char.ToUpper(u.RagSoc[0]).ToString() : "ZZZ")
+            .ThenBy(u => u.RagSoc)
+            .ToList();
+
+        userState.GroupedUserList = BuildGroupedList(sorted);
+        userState.FilteredGroupedUserList = userState.GroupedUserList;
+
+        userState.NotifyUsersLoaded();
+    }
+
+    private static List<UserDisplayItem> BuildGroupedList(List<ContactDTO> users)
+    {
+        var grouped = new List<UserDisplayItem>();
+        string? lastHeader = null;
+
+        foreach (var user in users)
+        {
+            var firstChar = char.ToUpper(user.RagSoc[0]);
+            var currentLetter = char.IsLetter(firstChar) ? firstChar.ToString() : "#";
+
+            var showHeader = currentLetter != lastHeader;
+            lastHeader = currentLetter;
+
+            grouped.Add(new UserDisplayItem
+            {
+                User = user,
+                ShowHeader = showHeader,
+                HeaderLetter = currentLetter
+            });
+        }
+
+        return grouped;
+    }
+}