Fix opener not trigger when tts disabled

engine/core/duplex_pipeline.py

@@ -408,14 +408,20 @@ class DuplexPipeline:
             return None
 
         prompt_hint = (self._runtime_greeting or "").strip()
+        system_context = (self.conversation.system_prompt or self._runtime_system_prompt or "").strip()
+        # Keep context concise to avoid overloading greeting generation.
+        if len(system_context) > 1200:
+            system_context = system_context[:1200]
         system_prompt = (
             "你是语音通话助手的开场白生成器。"
             "请只输出一句自然、简洁、友好的中文开场白。"
             "不要使用引号，不要使用 markdown，不要加解释。"
         )
         user_prompt = "请生成一句中文开场白（不超过25个汉字）。"
+        if system_context:
+            user_prompt += f"\n\n以下是该助手的系统提示词，请据此决定语气、角色和边界：\n{system_context}"
         if prompt_hint:
-            user_prompt += f" 风格提示：{prompt_hint}"
+            user_prompt += f"\n\n额外风格提示：{prompt_hint}"
 
         try:
             generated = await self.llm_service.generate(
@@ -532,23 +538,24 @@ class DuplexPipeline:
             if not self._outbound_task or self._outbound_task.done():
                 self._outbound_task = asyncio.create_task(self._outbound_loop())
 
-            # Speak greeting if configured
-            if tts_output_enabled:
-                greeting_to_speak = self.conversation.greeting
-                if self._generated_opener_enabled():
-                    generated_greeting = await self._generate_runtime_greeting()
-                    if generated_greeting:
-                        greeting_to_speak = generated_greeting
-                        self.conversation.greeting = generated_greeting
-                if greeting_to_speak:
-                    await self._send_event(
-                        ev(
-                            "assistant.response.final",
-                            text=greeting_to_speak,
-                            trackId=self.session_id,
-                        ),
-                        priority=20,
-                    )
+            # Resolve greeting once per session start.
+            # Always emit text opener event so text-only sessions can display it.
+            greeting_to_speak = self.conversation.greeting
+            if self._generated_opener_enabled():
+                generated_greeting = await self._generate_runtime_greeting()
+                if generated_greeting:
+                    greeting_to_speak = generated_greeting
+                    self.conversation.greeting = generated_greeting
+            if greeting_to_speak:
+                await self._send_event(
+                    ev(
+                        "assistant.response.final",
+                        text=greeting_to_speak,
+                        trackId=self.session_id,
+                    ),
+                    priority=20,
+                )
+                if tts_output_enabled:
                     await self._speak(greeting_to_speak)
 
         except Exception as e: