Enhance workflow engine and frontend components with transition speech support

- Introduce edge transition speech functionality in the WorkflowEngine to provide optional speech during node transitions.
- Update pipeline execution to utilize the new transition speech feature, enhancing user experience by masking delays during transitions.
- Modify frontend components to support transition speech in edge specifications, allowing users to define and edit transition speech for edges.
- Refactor edge handling logic in the WorkflowEditor to accommodate the new transition speech field, improving workflow management capabilities.

backend/services/pipecat/pipeline.py

@@ -346,9 +346,18 @@ async def run_pipeline(transport, cfg: AssistantConfig) -> None:
         await emit_node_active(target)
         apply_node(target)
 
-    def make_transition_handler(target: str):
+    async def speak_transition(edge: dict | None) -> None:
+        """切换瞬间播报过渡语(可选),掩盖切节点/新一轮生成的延迟。不写入上下文。"""
+        speech = engine.edge_transition_speech(edge)
+        if speech:
+            await worker.queue_frame(TTSSpeakFrame(speech, append_to_context=False))
+
+    def make_transition_handler(edge: dict):
+        target = edge.get("target")
+
         async def handler(params):
             logger.info(f"LLM 触发转移 → {engine.name(target)}")
+            await speak_transition(edge)
             await go_to_node(target)
             # 返回工具结果,pipecat 随即在新节点的提示/工具下继续生成
             await params.result_callback({"status": "ok"})
@@ -372,6 +381,7 @@ async def run_pipeline(transport, cfg: AssistantConfig) -> None:
         )
         if target and target != wf_state["current"]:
             logger.info(f"文本兜底触发转移 → {engine.name(target)}")
+            await speak_transition(engine.find_edge(wf_state["current"], target))
             # 仅切换节点提示/工具,下一轮用户输入即在新节点处理
             await go_to_node(target)
 
@@ -379,10 +389,9 @@ async def run_pipeline(transport, cfg: AssistantConfig) -> None:
     # 由各节点的 context.tools 控制当前可见哪些)。
     if workflow_active:
         for edge in engine.edges:
-            target = edge.get("target")
+            if edge.get("target"):
-            if target:
                 llm.register_function(
-                    engine.edge_fn_name(edge), make_transition_handler(target)
+                    engine.edge_fn_name(edge), make_transition_handler(edge)
                 )
         apply_node(wf_state["current"])  # 设初始节点的提示与工具
 

backend/services/workflow_engine.py

@@ -50,6 +50,18 @@ class WorkflowEngine:
     def edge_condition(self, edge: dict) -> str:
         return (edge.get("data") or {}).get("condition") or ""
 
+    def edge_transition_speech(self, edge: dict | None) -> str:
+        """命中该边、切换节点瞬间播报的过渡语(可选,掩盖延迟,不写入上下文)。"""
+        if not edge:
+            return ""
+        return (edge.get("data") or {}).get("transition_speech") or ""
+
+    def find_edge(self, source: str | None, target: str | None) -> dict | None:
+        for edge in self.edges:
+            if edge.get("source") == source and edge.get("target") == target:
+                return edge
+        return None
+
     def edge_description(self, edge: dict) -> str:
         """作为转移函数的 description 交给 LLM:满足该条件时模型应调用此函数。"""
         cond = self.edge_condition(edge)

frontend/src/components/workflow/WorkflowEditor.tsx

@@ -120,7 +120,12 @@ function fromFlow(nodes: Node[], edges: Edge[]): WorkflowGraph {
       id: e.id,
       source: e.source,
       target: e.target,
-      data: (e.data as { condition?: string; label?: string }) ?? {},
+      data:
+        (e.data as {
+          condition?: string;
+          label?: string;
+          transition_speech?: string;
+        }) ?? {},
     })),
   };
 }
@@ -238,7 +243,14 @@ function Canvas({
   );
 
   const updateEdgeData = useCallback(
-    (id: string, patch: { condition?: string; label?: string }) => {
+    (
+      id: string,
+      patch: {
+        condition?: string;
+        label?: string;
+        transition_speech?: string;
+      },
+    ) => {
       setEdges((es) =>
         es.map((e) =>
           e.id === id ? { ...e, data: { ...(e.data ?? {}), ...patch } } : e,
@@ -677,12 +689,23 @@ function EdgeForm({
   onDelete,
 }: {
   edge: Edge;
-  onSave: (patch: { condition: string; label: string }) => void;
+  onSave: (patch: {
+    condition: string;
+    label: string;
+    transition_speech: string;
+  }) => void;
   onDelete: () => void;
 }) {
-  const data = (edge.data ?? {}) as { condition?: string; label?: string };
+  const data = (edge.data ?? {}) as {
+    condition?: string;
+    label?: string;
+    transition_speech?: string;
+  };
   const [label, setLabel] = useState(data.label ?? "");
   const [condition, setCondition] = useState(data.condition ?? "");
+  const [transitionSpeech, setTransitionSpeech] = useState(
+    data.transition_speech ?? "",
+  );
 
   return (
     <>
@@ -718,6 +741,22 @@ function EdgeForm({
             className="resize-none border-hairline-strong bg-background text-foreground placeholder:text-muted-soft"
           />
         </div>
+
+        <div className="flex flex-col gap-2">
+          <label className="text-sm font-medium text-foreground">
+            过渡语(可选)
+          </label>
+          <Textarea
+            rows={2}
+            value={transitionSpeech}
+            placeholder="切换到下一节点前先说的一句过渡语,用于掩盖延迟,例如:好的,我帮你转接。"
+            onChange={(e) => setTransitionSpeech(e.target.value)}
+            className="resize-none border-hairline-strong bg-background text-foreground placeholder:text-muted-soft"
+          />
+          <span className="text-xs text-muted-soft">
+            命中该条件、切换节点的瞬间播报,不写入对话上下文。
+          </span>
+        </div>
       </div>
 
       <DialogFooter className="flex-row justify-between sm:justify-between">
@@ -729,7 +768,13 @@ function EdgeForm({
           <Trash2 size={15} />
           删除连线
         </Button>
-        <Button onClick={() => onSave({ condition, label })}>保存条件</Button>
+        <Button
+          onClick={() =>
+            onSave({ condition, label, transition_speech: transitionSpeech })
+          }
+        >
+          保存条件
+        </Button>
       </DialogFooter>
     </>
   );

frontend/src/components/workflow/specs.ts

@@ -99,7 +99,7 @@ export type WorkflowGraph = {
     id: string;
     source: string;
     target: string;
-    data?: { condition?: string; label?: string };
+    data?: { condition?: string; label?: string; transition_speech?: string };
   }>;
   viewport?: { x: number; y: number; zoom: number };
 };