feat 1.增加 建议词 机制 2.对话生图实现

src/routers/chat.py

@@ -4,7 +4,7 @@ from fastapi import APIRouter
 from fastapi.responses import StreamingResponse
 from src.schemas.chat import ChatRequest, HistoryResponse, HistoryItem
 from src.server.agent.graph import app  # 导入已经 compile 好的 graph
-from langchain_core.messages import HumanMessage
+from langchain_core.messages import HumanMessage, SystemMessage
 
 router = APIRouter(prefix="/chat", tags=["Furniture Design Chat"])
 
@@ -57,38 +57,114 @@ async def chat_stream(request: ChatRequest):
     # 如果是回溯操作，我们生成一个新的 ID，或者由前端传入一个新的 target_thread_id
     is_branching = source_thread_id and checkpoint_id
     target_thread_id = str(uuid.uuid4())[:8] if is_branching else (source_thread_id or str(uuid.uuid4())[:8])
+    # 2. 获取配置参数
+    temp = request.config_params.temperature if request.config_params else 0.7
 
-    # 2. 如果是分叉请求，我们需要先“搬家”状态
+    # 构建基础 Config
+    current_config = {
+        "configurable": {
+            "thread_id": target_thread_id,
+            "llm_temperature": temp
+        }
+    }
+    # 3. 处理状态初始化与分支
+    initial_messages = []
+
+    # 如果是全新的对话（没有 source_thread_id），或者明确要求分叉
+    if not source_thread_id or is_branching:
+        # 如果用户传了标签，构造 SystemMessage 注入上下文
+        if request.config_params:
+            cp = request.config_params
+            system_prompt = (
+                f"Current furniture design background settings：\n"
+                f"- type: {cp.type}\n"
+                f"- space/region: {cp.region}\n"
+                f"- style tendency: {cp.style}\n"
+                f"Please strictly follow the above settings in subsequent conversations。"
+            )
+            initial_messages.append(SystemMessage(content=system_prompt))
+
+    # 4. 执行分叉逻辑（搬运旧数据）
     if is_branching:
-        # 获取旧状态
-        source_config = {"configurable": {"thread_id": source_thread_id, "checkpoint_id": checkpoint_id}}
+        source_config = {
+            "configurable": {
+                "thread_id": source_thread_id,
+                "checkpoint_id": checkpoint_id
+            }
+        }
         older_state = await app.aget_state(source_config)
 
-        # 将旧状态的消息，作为新 thread 的初始值注入
-        # 注意：这里我们手动把旧消息塞给新 thread
-        new_config = {"configurable": {"thread_id": target_thread_id}}
-        await app.aupdate_state(new_config, older_state.values)
+        # 将旧消息和我们新定义的 SystemMessage 合并
+        # update_state 会将这些消息推送到新 thread 的存储中
+        combined_values = older_state.values.copy()
+        if initial_messages:
+            combined_values["messages"] = list(combined_values["messages"]) + initial_messages
 
-        # 现在的 config 指向新 Thread
-        current_config = new_config
-    else:
-        current_config = {"configurable": {"thread_id": target_thread_id}}
+        await app.aupdate_state(current_config, combined_values)
 
     async def event_generator():
-        # 告诉前端：现在是在哪个 Thread 上工作（如果是分叉，前端需要更新本地存储的 ID）
-        yield f"data: {json.dumps({'thread_id': target_thread_id, 'is_branch': is_branching}, ensure_ascii=False)}\n\n"
+        # 初始推送状态信息
+        yield f"data: {json.dumps({'thread_id': target_thread_id, 'is_branch': is_branching, 'status': 'start'}, ensure_ascii=False)}\n\n"
+
+        # 构造本次请求的输入
+        # 如果是第一次开始，且有 initial_messages，则连同 user message 一起发送
+        # --- 核心逻辑：构造本次请求的消息列表 ---
+        new_messages = []
+        if not source_thread_id and initial_messages:
+            new_messages.extend(initial_messages)
+            # 添加用户消息
+        new_messages.append(HumanMessage(content=request.message))
+
+        # --- 新增：强制绘图指令注入 ---
+        # if request.force_sketch:
+        #     force_instruction = HumanMessage(
+        #         content="[SYSTEM_DIRECTIVE]: 用户点击了强制生成按钮。请立即根据当前上下文调用 generate_furniture_sketch 工具生成草图，无需确认。"
+        #     )
+        #     new_messages.append(force_instruction)
+
+        input_data = {"messages": new_messages}
 
         async for event in app.astream(
-                {"messages": [HumanMessage(content=request.message)]},
+                input_data,
                 current_config,
                 stream_mode="updates"
         ):
-            # ... 发送流式内容的逻辑保持不变 ...
             for node_name, output in event.items():
                 if "messages" in output:
-                    msg = output["messages"][-1]
+                    # 获取最新 state 以获取 checkpoint_id
                     state = await app.aget_state(current_config)
-                    yield f"data: {json.dumps({'node': node_name, 'content': msg.content, 'checkpoint_id': state.config['configurable']['checkpoint_id']}, ensure_ascii=False)}\n\n"
+                    current_cp_id = state.config["configurable"].get("checkpoint_id")
+
+                    # 遍历本次 update 产生的所有消息
+                    for msg in output["messages"]:
+                        payload = {
+                            "node": node_name,
+                            "content": "",
+                            "image_url": None,
+                            "checkpoint_id": current_cp_id,
+                            "suggestions": []
+                        }
+
+                        # --- 核心改动：提取建议按钮 ---
+                        # 无论是不是 Suggester 节点，只要消息里带了建议就提取
+                        if hasattr(msg, "additional_kwargs") and "suggestions" in msg.additional_kwargs:
+                            payload["suggestions"] = msg.additional_kwargs["suggestions"]
+
+                        content = msg.content
+                        # 逻辑判断：MinIO 图片处理
+                        if node_name == "Visualizer" and str(content).endswith("png") and "furniture/sketches" in str(content):
+                            payload["image_url"] = content
+                            payload["content"] = "已为您生成设计草图"
+                        else:
+                            payload["content"] = content
+
+                        # 如果消息既没有文本、也没有图片、也没有建议（比如中间的 ToolCall 消息），则跳过
+                        if not payload["content"] and not payload["image_url"] and not payload["suggestions"]:
+                            continue
+
+                        yield f"data: {json.dumps(payload, ensure_ascii=False)}\n\n"
+
+        yield f"data: {json.dumps({'status': 'end'}, ensure_ascii=False)}\n\n"
 
     return StreamingResponse(event_generator(), media_type="text/event-stream")
 
@@ -147,11 +223,11 @@ async def get_chat_history(thread_id: str):
                 last_msg = msgs[-1]
                 # 获取内容并做摘要截断
                 content = getattr(last_msg, "content", str(last_msg))
-                msg_content = content[:50] + ("..." if len(content) > 50 else "")
+                msg_content = content
 
         history_data.append(HistoryItem(
             checkpoint_id=state.config["configurable"]["checkpoint_id"],
-            last_message=msg_content[:50],
+            last_message=msg_content,
             node=state.metadata.get("source"),
             timestamp=state.metadata.get("step")
         ))