Updates

BudgetApp/Services/ToastService.cs

@@ -0,0 +1,8 @@
+namespace BudgetApp.Services;
+
+public sealed class ToastService
+{
+    public event Action<string>? OnShow;
+
+    public void Show(string message) => OnShow?.Invoke(message);
+}

BudgetApp/Services/TransactionService.cs

@@ -116,14 +116,43 @@ public class TransactionService(ApplicationDbContext db)
 
         if (transaction is null) return;
 
+        var isPartOfSeries = transaction.RecurrenceType != RecurrenceType.None
+                          || transaction.ParentTransactionId is not null;
+
         transaction.Description = description;
         transaction.Amount = amount;
         transaction.Date = date;
         transaction.Type = type;
         transaction.AccountId = accountId;
         transaction.CategoryId = categoryId;
-        transaction.RecurrenceType = recurrenceType;
-        transaction.RecurrenceEndDate = recurrenceEndDate;
+
+        if (isPartOfSeries)
+        {
+            // Cascade edits to all future occurrences in the series
+            var parentId = transaction.ParentTransactionId ?? transaction.Id;
+            var cutoffDate = transaction.Date.Date;
+
+            var futureSiblings = await _db.Transactions
+                .Where(t => (t.Id == parentId || t.ParentTransactionId == parentId)
+                            && t.Id != id
+                            && t.Date.Date >= cutoffDate)
+                .ToListAsync();
+
+            foreach (var sibling in futureSiblings)
+            {
+                sibling.Description = description;
+                sibling.Amount = amount;
+                sibling.Type = type;
+                sibling.AccountId = accountId;
+                sibling.CategoryId = categoryId;
+            }
+        }
+        else
+        {
+            // Standalone transaction — preserve existing recurrence state (None)
+            transaction.RecurrenceType = recurrenceType;
+            transaction.RecurrenceEndDate = recurrenceEndDate;
+        }
 
         await _db.SaveChangesAsync();
     }