chore: directory migration - gateway→server, web→client/electron

client/electron/src/api/sse.ts

@@ -0,0 +1,109 @@
+import { API_BASE, withToken } from './config';
+
+export type SSEEventHandler = (eventType: string, data: Record<string, unknown>) => void;
+export type SSEStatus = 'connecting' | 'connected' | 'disconnected' | 'reconnecting';
+
+const EVENTS = [
+  'new_mail',
+  'permission_decision',
+  'session_update',
+  'session_archived',
+  'agent_online'
+] as const;
+
+let es: EventSource | null = null;
+let handlers: SSEEventHandler[] = [];
+let retryTimer: ReturnType<typeof setTimeout> | null = null;
+let backoff = 1000;
+let _status: SSEStatus = 'disconnected';
+let statusHandlers: Array<(s: SSEStatus) => void> = [];
+
+/** 监听 SSE 连接状态变化 */
+export function onSSEStatus(handler: (s: SSEStatus) => void): () => void {
+  statusHandlers.push(handler);
+  return () => {
+    statusHandlers = statusHandlers.filter(h => h !== handler);
+  };
+}
+
+/** 当前 SSE 连接状态 */
+export function getSSEStatus(): SSEStatus {
+  return _status;
+}
+
+function setStatus(s: SSEStatus) {
+  if (_status === s) return;
+  _status = s;
+  statusHandlers.forEach(h => h(s));
+}
+
+export function connectSSE(onEvent: SSEEventHandler): () => void {
+  handlers.push(onEvent);
+  if (!es) open();
+
+  return () => {
+    handlers = handlers.filter(h => h !== onEvent);
+    if (handlers.length === 0) close();
+  };
+}
+
+function open() {
+  close(false);
+  setStatus('connecting');
+  // EventSource 无法设置请求头：Cookie 模式靠同源 Cookie，
+  // 密钥模式只能把令牌放进 query（服务端仅此端点与附件下载接受 ?access_token=）。
+  es = new EventSource(withToken(`${API_BASE}/events/stream`), { withCredentials: true });
+
+  // EventSource 会自动重连，但它的 readyState 在网络断开时
+  // 不一定及时反映状态。用 onopen 判断实际连上了。
+  es.onopen = () => {
+    backoff = 1000;
+    setStatus('connected');
+  };
+
+  es.addEventListener('connected', () => {
+    backoff = 1000;
+    setStatus('connected');
+  });
+
+  for (const name of EVENTS) {
+    es.addEventListener(name, (e: MessageEvent) => {
+      let data: Record<string, unknown> = {};
+      try {
+        data = JSON.parse(e.data);
+      } catch {
+        /* 忽略非 JSON 负载 */
+      }
+      handlers.forEach(h => h(name, data));
+    });
+  }
+
+  es.onerror = () => {
+    close(false);
+    if (handlers.length === 0) return;
+    if (retryTimer) return;
+    setStatus('reconnecting');
+    retryTimer = setTimeout(() => {
+      retryTimer = null;
+      backoff = Math.min(backoff * 2, 15000);
+      open();
+    }, backoff);
+  };
+}
+
+function close(clearHandlers = true) {
+  if (retryTimer) {
+    clearTimeout(retryTimer);
+    retryTimer = null;
+  }
+  if (es) {
+    es.close();
+    es = null;
+  }
+  if (clearHandlers) handlers = [];
+  setStatus('disconnected');
+}
+
+export function disconnectSSE() {
+  close();
+}