desktop/chat: fallback de polling se WS falhar

apps/desktop/src/chat/convexMachineClient.ts

@@ -34,6 +34,11 @@ type MachineUpdatePayload = {
   totalUnread: number
 }
 
+type MessagesPayload = {
+  messages: ChatMessage[]
+  hasSession: boolean
+}
+
 const FN_CHECK_UPDATES = "liveChat.checkMachineUpdates" as const
 const FN_LIST_MESSAGES = "liveChat.listMachineMessages" as const
 const FN_POST_MESSAGE = "liveChat.postMachineMessage" as const
@@ -92,13 +97,71 @@ export async function subscribeMachineUpdates(
   onError?: (error: Error) => void
 ): Promise<() => void> {
   const { client, token } = await ensureClient()
+  let stopped = false
+  let pollTimer: ReturnType<typeof setInterval> | null = null
+
+  const stopPoll = () => {
+    if (pollTimer) {
+      clearInterval(pollTimer)
+      pollTimer = null
+    }
+  }
+
+  const startPoll = async () => {
+    stopPoll()
+    try {
+      const { apiBaseUrl } = await getMachineStoreConfig()
+      const poll = async () => {
+        try {
+          const res = await fetch(`${apiBaseUrl}/api/machines/chat/poll`, {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify({ machineToken: token }),
+          })
+          if (!res.ok) throw new Error(`poll failed: ${res.status}`)
+          const data = (await res.json()) as MachineUpdatePayload
+          if (!stopped) callback(data)
+        } catch (err) {
+          if (!stopped) onError?.(err as Error)
+        }
+      }
+      await poll()
+      pollTimer = setInterval(poll, 4000)
+    } catch (err) {
+      onError?.(err as Error)
+    }
+  }
+
   const sub = client.onUpdate(
     FN_CHECK_UPDATES as unknown as FunctionReference<"query">,
     { machineToken: token },
-    (value) => callback(value),
-    onError
+    (value) => {
+      stopPoll()
+      callback(value)
+    },
+    (err) => {
+      onError?.(err)
+      startPoll().catch(() => {
+        // erro já reportado via onError
+      })
+    }
   )
-  return () => sub.unsubscribe()
+
+  // fallback caso a inscrição falhe imediatamente
+  setTimeout(() => {
+    if (stopped) return
+    // Se não houver mensagens recebidas pelo WS em 3s, inicia polling
+    // (o callback do WS encerra o polling caso volte a funcionar)
+    startPoll().catch(() => {
+      // erro já reportado via onError
+    })
+  }, 3000)
+
+  return () => {
+    stopped = true
+    stopPoll()
+    sub.unsubscribe()
+  }
 }
 
 export async function subscribeMachineMessages(
@@ -107,16 +170,83 @@ export async function subscribeMachineMessages(
   onError?: (error: Error) => void
 ): Promise<() => void> {
   const { client, token } = await ensureClient()
+  let stopped = false
+  let pollTimer: ReturnType<typeof setInterval> | null = null
+  let lastSince = 0
+
+  const stopPoll = () => {
+    if (pollTimer) {
+      clearInterval(pollTimer)
+      pollTimer = null
+    }
+  }
+
+  const startPoll = async () => {
+    stopPoll()
+    try {
+      const { apiBaseUrl } = await getMachineStoreConfig()
+      const poll = async () => {
+        try {
+          const res = await fetch(`${apiBaseUrl}/api/machines/chat/messages`, {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify({
+              action: "list",
+              machineToken: token,
+              ticketId,
+              since: lastSince || undefined,
+            }),
+          })
+          if (!res.ok) throw new Error(`messages poll failed: ${res.status}`)
+          const data = (await res.json()) as MessagesPayload
+          if (!stopped) {
+            callback(data)
+            const newest = data.messages.reduce((max, msg) => Math.max(max, msg.createdAt), lastSince)
+            lastSince = newest
+          }
+        } catch (err) {
+          if (!stopped) onError?.(err as Error)
+        }
+      }
+      await poll()
+      pollTimer = setInterval(poll, 4000)
+    } catch (err) {
+      onError?.(err as Error)
+    }
+  }
+
   const sub = client.onUpdate(
     FN_LIST_MESSAGES as unknown as FunctionReference<"query">,
     {
       machineToken: token,
       ticketId,
     },
-    (value) => callback(value),
-    onError
+    (value) => {
+      stopPoll()
+      callback(value)
+      const newest = value.messages.reduce((max, msg) => Math.max(max, msg.createdAt), lastSince)
+      lastSince = newest
+    },
+    (err) => {
+      onError?.(err)
+      startPoll().catch(() => {
+        // erro já reportado via onError
+      })
+    }
   )
-  return () => sub.unsubscribe()
+
+  setTimeout(() => {
+    if (stopped) return
+    startPoll().catch(() => {
+      // erro já reportado via onError
+    })
+  }, 3000)
+
+  return () => {
+    stopped = true
+    stopPoll()
+    sub.unsubscribe()
+  }
 }
 
 export async function sendMachineMessage(input: {