feat: Add Cancelled status for Order and ServiceOrder, return type as number

- Add Cancelled status to OrderStatus enum (4=Cancelled)
- Add Cancel() method to Order entity with proper validation
- Update Order UpdateStatus method to handle Cancelled status
- Add IsCancelled computed property to Order entity
- Update ServiceOrder DTOs to return Type as number instead of string
- Update GetServiceOrdersQueryHandler to map Type as (int)so.Type
- Update OrdersController status mapping to include Cancelled (4)
- Update Order status handler business logic:
  * Order Cancelled -> Vehicle Available (release reserved vehicle)
- Update ServiceOrder status handler to handle Cancelled status
- ServiceOrder Type now returns: 1=PreDelivery, 2=Maintenance, 3=Repair
- ServiceOrder Status now returns: 1=Scheduled, 2=InProgress, 3=Completed, 4=Cancelled

Author: Dang

VehicleShowroomManagement/src/Application/Features/Orders/Commands/UpdateOrderStatus/UpdateOrderStatusCommandHandler.cs

@@ -40,6 +40,12 @@ public async Task<Unit> Handle(UpdateOrderStatusCommand request, CancellationTok
                         vehicle.Sell();
                         await vehicleRepository.UpdateAsync(vehicle, cancellationToken);
                     }
+                    else if (request.Status == OrderStatus.Cancelled)
+                    {
+                        // When order is cancelled, make vehicle available again
+                        vehicle.UpdateStatus(VehicleStatus.Available);
+                        await vehicleRepository.UpdateAsync(vehicle, cancellationToken);
+                    }
                 }
             }
 

VehicleShowroomManagement/src/Application/Features/ServiceOrders/Commands/UpdateStatus/UpdateServiceOrderStatusCommandHandler.cs

@@ -29,8 +29,13 @@ public async Task<UpdateServiceOrderStatusResult> Handle(UpdateServiceOrderStatu
                 Message = "Service order status updated successfully"
             };
 
-            // Business Logic: Only PreDelivery service orders affect Order/Vehicle status
-            if (request.Status == ServiceOrderStatus.Completed && serviceOrder.Type == ServiceType.PreDelivery)
+            // Business Logic: Handle different status updates
+            if (request.Status == ServiceOrderStatus.Cancelled)
+            {
+                // For cancelled service orders, no impact on Order/Vehicle status
+                result.Message = "Service order cancelled";
+            }
+            else if (request.Status == ServiceOrderStatus.Completed && serviceOrder.Type == ServiceType.PreDelivery)
             {
                 // Get related order
                 var order = await orderRepository.GetByIdAsync(serviceOrder.OrderId, cancellationToken) ?? throw new ArgumentException("Related order not found");

VehicleShowroomManagement/src/Application/Features/ServiceOrders/Queries/GetServiceOrders/GetServiceOrdersQueryHandler.cs

@@ -50,7 +50,7 @@ public async Task<ServiceOrdersResponse> Handle(GetServiceOrdersQuery request, C
                 AppointmentDate = so.AppointmentDate,
                 Description = so.Description,
                 Cost = so.Cost,
-                Type = so.Type.ToString(),
+                Type = (int)so.Type,
                 Status = (int)so.Status
             }).ToList();
 

VehicleShowroomManagement/src/Application/Features/ServiceOrders/Queries/GetServiceOrders/ServiceOrderDto.cs

@@ -13,7 +13,7 @@ public class ServiceOrderDto
         public DateTime? AppointmentDate { get; set; }
         public string? Description { get; set; }
         public decimal Cost { get; set; }
-        public string Type { get; set; } = string.Empty;
+        public int Type { get; set; }
         public int Status { get; set; }
     }
 

VehicleShowroomManagement/src/Domain/Entities/Order.cs

@@ -131,6 +131,18 @@ public void Complete()
         UpdatedAt = DateTime.UtcNow;
     }
 
+    public void Cancel()
+    {
+        if (Status == OrderStatus.Completed)
+            throw new InvalidOperationException("Cannot cancel a completed order");
+
+        if (Status == OrderStatus.Cancelled)
+            throw new InvalidOperationException("Order is already cancelled");
+
+        Status = OrderStatus.Cancelled;
+        UpdatedAt = DateTime.UtcNow;
+    }
+
     public void UpdateStatus(OrderStatus status)
     {
         switch (status)
@@ -148,6 +160,9 @@ public void UpdateStatus(OrderStatus status)
             case OrderStatus.Completed:
                 Complete();
                 break;
+            case OrderStatus.Cancelled:
+                Cancel();
+                break;
             default:
                 throw new InvalidOperationException("Unsupported status transition");
         }
@@ -175,6 +190,7 @@ public void SetReservationPeriod(DateTime from, DateTime to)
         public bool IsPending => Status == OrderStatus.Pending;
         public bool IsConfirmed => Status == OrderStatus.Confirmed;
         public bool IsCompleted => Status == OrderStatus.Completed;
+        public bool IsCancelled => Status == OrderStatus.Cancelled;
         public bool HasVehicle => !string.IsNullOrEmpty(VehicleId);
     }
 }

VehicleShowroomManagement/src/Domain/Enums/OrderStatus.cs

@@ -18,6 +18,11 @@ public enum OrderStatus
         /// <summary>
         /// Order has been completed
         /// </summary>
-        Completed = 3
+        Completed = 3,
+        
+        /// <summary>
+        /// Order has been cancelled
+        /// </summary>
+        Cancelled = 4
     }
 }

VehicleShowroomManagement/src/WebAPI/Controllers/OrdersController.cs

@@ -36,12 +36,13 @@ public async Task<IActionResult> GetOrders(
             OrderStatus? statusEnum = null;
             if (status.HasValue)
             {
-                // 1=Pending, 2=Confirmed, 3=Completed
+                // 1=Pending, 2=Confirmed, 3=Completed, 4=Cancelled
                 statusEnum = status.Value switch
                 {
                     1 => OrderStatus.Pending,
                     2 => OrderStatus.Confirmed,
                     3 => OrderStatus.Completed,
+                    4 => OrderStatus.Cancelled,
                     _ => null
                 };
             }