add validation topic on send prompt if not relevan

app/Services/OpenAIService.php

@@ -27,6 +27,11 @@ class OpenAIService
             return "Template prompt tidak ditemukan.";
         }
 
+        $validationResponse = $this->validatePromptTopic($prompt);
+        if ($validationResponse !== 'VALID') {
+            return "Prompt yang Anda masukkan tidak relevan dengan data PUPR/SIMBG/DPUTR atau pekerjaan sejenis.";
+        }
+
         // Ambil template berdasarkan kategori
         $promptTemplate = $jsonData[$mainContent]['prompt'];
 
@@ -273,4 +278,26 @@ class OpenAIService
     
     //     return trim($response['choices'][0]['message']['content'] ?? 'No response');
     // }
+
+    public function validatePromptTopic($prompt)
+    {
+        $messages = [
+            [
+                'role' => 'system',
+                'content' => "You are a classification expert. Determine if the user's request is related to the Indonesian Ministry of Public Works and Public Housing (PUPR), DPUTR, SIMBG, or construction-related tasks managed by these institutions. 
+            
+    Only respond with:
+    - VALID → if it's relevant to those topics
+    - INVALID → if not related at all"
+            ],
+            ['role' => 'user', 'content' => $prompt],
+        ];
+
+        $response = $this->client->chat()->create([
+            'model' => 'gpt-4o-mini',
+            'messages' => $messages,
+        ]);
+
+        return trim($response['choices'][0]['message']['content'] ?? 'INVALID');
+    }
 }