feat(chat): implement WebSocket message sending and integrate with chat state machine

src/stores/chat/chat-machine.actors.ts

@@ -17,7 +17,7 @@
 
 import { fromPromise, fromCallback } from "xstate";
 
-import { createChatWebSocket } from "@/core/net/chat-websocket";
+import { createChatWebSocket, ChatWebSocket } from "@/core/net/chat-websocket";
 import { Result } from "@/utils/result";
 
 import {
@@ -30,6 +30,28 @@ import {
 } from "./chat-machine.helpers";
 import type { ChatEvent } from "./chat-events";
 
+// ============================================================
+// 共享 WS 引用（chatWebSocketActor ↔ sendMessageWsActor）
+// ============================================================
+/**
+ * 活跃 ChatWebSocket 单例引用（module-level）。
+ * - `chatWebSocketActor` 在 connect 后写入、cleanup 时清空
+ * - `sendMessageWsActor` 读取并调 `ws.sendMessage(content)`
+ *
+ * 为什么用 module-level 而非 context.wsRef：
+ *   1) `ChatWebSocket` 是带回调 + 重连 timer 的非可序列化对象，放进
+ *      XState context 会污染快照、警告 non-serializable
+ *   2) userSession 同一时间只可能有一个活跃 WS（parent-level invoke），
+ *      module 单例的语义和"userSession 内一个活跃连接"一一对应
+ *   3) 不需要重构 ChatWebSocket 类的对外 API
+ */
+let activeChatWebSocket: ChatWebSocket | null = null;
+
+/** 暴露给 `sendMessageWsActor` 读取（测试也可 import） */
+export function getActiveChatWebSocket(): ChatWebSocket | null {
+  return activeChatWebSocket;
+}
+
 // ============================================================
 // Init 任务 1：拉游客配额（fromPromise，纯 local）
 // ============================================================
@@ -196,6 +218,13 @@ export const chatWebSocketActor = fromCallback<ChatEvent, { token: string }>(
     console.log("[chat-machine] chatWebSocketActor createChatWebSocket DONE", {
       wsType: ws.constructor.name,
     });
+
+    // 写入 module-level 共享引用 —— sendMessageWsActor 借此调 ws.sendMessage()
+    activeChatWebSocket = ws;
+    console.log("[chat-machine] chatWebSocketActor activeChatWebSocket SET", {
+      isConnected: ws.isConnected,
+    });
+
     ws.onConnected = (userId) => {
       console.log("[chat-machine] WS onConnected", {
         userId,
@@ -234,10 +263,62 @@ export const chatWebSocketActor = fromCallback<ChatEvent, { token: string }>(
       console.log(
         "[chat-machine] chatWebSocketActor CLEANUP (parent state exit / logout / cross-transition / unmount)",
       );
+      // 清空 module-level 引用 —— 严格用 `=== ws` 判等，避免覆盖更新的实例
+      if (activeChatWebSocket === ws) {
+        activeChatWebSocket = null;
+        console.log("[chat-machine] chatWebSocketActor activeChatWebSocket CLEARED");
+      }
       ws.disconnect();
     };
   },
 );
 
+// ============================================================
+// WebSocket: per-send callback
+// ============================================================
+/**
+ * WS 发送消息（userSession.sendingViaWs 期间 invoke）
+ * - 走 `activeChatWebSocket.sendMessage(content)`
+ * - 成功后 AI 回复通过 `chatWebSocketActor` 的 `onSentence` → `ChatAISentenceReceived` 流回
+ * - 失败抛错 → state machine 的 `onError` 兜底（清 isReplyingAI、回 ready）
+ *
+ * 与 sendMessageHttpActor 的区别：
+ *   - sendMessageHttpActor: 一次发送 = 一次返回（HTTP response = AI reply）
+ *   - sendMessageWsActor: 一次发送 = 0 次直接返回（WS 异步流式回 reply，actor 本身不返 reply）
+ *
+ * 选 fromPromise 而非 fromCallback：
+ *   - 本 actor 是 fire-and-forget —— sync 内同步执行 ws.sendMessage，立即 resolve
+ *   - actor 本身没有"完成"语义（done 来自 WS 事件流，不来自这个 actor）
+ *   - 抛错走 onError 通道
+ *   - fromPromise 的 input type 推断比 fromCallback<void, ...> 稳定（XState v5 已知坑）
+ */
+export const sendMessageWsActor = fromPromise<void, { content: string }>(
+  async ({ input }) => {
+    console.log("[chat-machine] sendMessageWsActor ENTRY", {
+      contentLength: input.content.length,
+      contentPreview: input.content.slice(0, 50),
+    });
+    const ws = getActiveChatWebSocket();
+    if (!ws) {
+      console.error("[chat-machine] sendMessageWsActor no activeChatWebSocket");
+      throw new Error("[chat-machine] sendMessageWs: no active WebSocket (actor not running)");
+    }
+    console.log("[chat-machine] sendMessageWsActor calling ws.sendMessage", {
+      isConnected: ws.isConnected,
+    });
+    const ok = ws.sendMessage(input.content);
+    if (!ok) {
+      console.error(
+        "[chat-machine] sendMessageWsActor ws.sendMessage returned false (not OPEN)",
+      );
+      throw new Error("[chat-machine] sendMessageWs: WebSocket not OPEN");
+    }
+    console.log(
+      "[chat-machine] sendMessageWsActor ws.sendMessage OK, awaiting AI sentence stream",
+    );
+    // resolve 不返值 —— AI reply 由 chatWebSocketActor 的 ChatAISentenceReceived 流回
+  },
+);
+
 // Re-export `UiMessage` type for the chat-machine.ts public API
 type UiMessage = import("@/models/chat/ui-message").UiMessage;