add custom prompt to open AI translation

config/translator.php

@@ -31,6 +31,14 @@
             'model' => env('OPENAI_MODEL', 'gpt-4o'),
             'api_key' => env('OPENAI_API_KEY'),
             'organization_id' => env('OPENAI_ORGANIZATION'),
+
+            /**
+             * Custom prompt to enhance translation quality.
+             * 
+             * Example:
+             * 'custom_prompt' => 'This application translates medical terms consistently throughout.'
+             */
+            'custom_prompt' => ''
         ],
         'deepl' => [
             'driver' => Bottelet\TranslationChecker\Translator\DeeplTranslator::class,

src/Translator/OpenAiTranslator.php

@@ -17,9 +17,13 @@ public function translate(string $text, string $targetLanguage, string $sourceLa
 Instructions:
 1. Translate the entire string from {$sourceLanguage} to {$targetLanguage}.
 2. Words prefixed with a colon (:) are special tokens. Do not translate these tokens, keep them as is.
-3. Maintain the original structure and formatting of the input string.
+3. Maintain the original structure and formatting of the input string.";
 
-Input format: A single string in {$sourceLanguage}, potentially containing words prefixed with colons.
+if (config('translator.translators.openai.custom_prompt')) {
+    $systemPrompt .= $this->CustomPrompt();
+}
+
+$systemPrompt .= "\nInput format: A single string in {$sourceLanguage}, potentially containing words prefixed with colons.
 
 Output format: respond with a single string in {$targetLanguage}, potentially containing words prefixed with colons.";
 
@@ -53,9 +57,13 @@ public function translateBatch(array $texts, string $targetLanguage, string $sou
 Instructions:
 1. Translate each string from {$sourceLanguage} to {$targetLanguage}.
 2. Words prefixed with a colon (:) are special tokens. Do not translate these tokens, keep them as is.
-3. Maintain the original structure and formatting of each input string.
+3. Maintain the original structure and formatting of each input string.\n";
+
+if (config('translator.translators.openai.custom_prompt')) {
+    $systemPrompt .= $this->CustomPrompt();
+}
 
-Input format: An array of strings in {$sourceLanguage}, potentially containing words prefixed with colons.
+$systemPrompt .="\nInput format: An array of strings in {$sourceLanguage}, potentially containing words prefixed with colons.
 
 Output format: Respond with a single JSON object. Each key-value pair in this object should represent one translation:
 - Key: The original string in {$sourceLanguage}
@@ -114,4 +122,9 @@ public function isConfigured(): bool
 
         return $openAiConfig['api_key'] && $openAiConfig['model'];
     }
+
+    private function CustomPrompt(): string
+    {
+        return "4. " . config('translator.translators.openai.custom_prompt') . "\n";   
+    }
 }