Added validation for process order with item code

app/Filament/Resources/ProcessOrderResource.php

@@ -144,6 +144,34 @@ class ProcessOrderResource extends Resource
                             $set('sfgNumberError', null);
                         }
                     })
+                    ->rule(function (callable $get) {
+                        return function (string $attribute, $value, \Closure $fail) use ($get) {
+
+                            $plantId = $get('plant_id');
+                            $itemId = $get('item_id');
+                            $processOrder = $value;
+                            //$currentId = $get('id'); // current editing record id
+
+                            if (! $plantId || ! $processOrder) {
+                                return;
+                            }
+
+                           $existing = ProcessOrder::where('plant_id', $plantId)
+                            ->where('process_order', $processOrder)
+                            ->where('item_id', '!=', $itemId)
+                            ->first();
+
+                            if ($existing) {
+
+                                Notification::make()
+                                    ->title('Duplicate Process Order!')
+                                    ->body("Process Order '{$value}' is already exist with item code '{$existing->item->code}'.")
+                                    ->danger()
+                                    ->send();
+                                $fail("process order already exists for this plant and item code '{$existing->item->code}'.");
+                            }
+                        };
+                    })
                     ->required(),
                 Forms\Components\TextInput::make('coil_number')
                     ->label('Coil Number')