feat: auto-start feishu login in client

web/app/login/page.tsx

@@ -1,7 +1,7 @@
 "use client"
 
 import type { FormEvent } from "react"
-import { useEffect, useMemo, useState } from "react"
+import { useEffect, useMemo, useRef, useState } from "react"
 import {
   ArrowRight,
   Building2,
@@ -21,8 +21,26 @@ type AuthConfig = {
   feishu_enabled?: boolean
 }
 
+function normalizeNextPath(value: string | null | undefined) {
+  const next = (value || "/").trim() || "/"
+  if (!next.startsWith("/") || next.startsWith("//")) return "/"
+  return next
+}
+
+function loginNextPath() {
+  if (typeof window === "undefined") return "/"
+  return normalizeNextPath(new URLSearchParams(window.location.search).get("next"))
+}
+
+function isFeishuClient() {
+  if (typeof window === "undefined") return false
+  const ua = window.navigator.userAgent.toLowerCase()
+  return ua.includes("feishu") || ua.includes("lark")
+}
+
 export default function LoginPage() {
   const [authConfig, setAuthConfig] = useState<AuthConfig | null>(null)
+  const [nextPath] = useState(loginNextPath)
   const [username, setUsername] = useState("")
   const [password, setPassword] = useState("")
   const [remember, setRemember] = useState(true)
@@ -31,6 +49,7 @@ export default function LoginPage() {
   const [hasError, setHasError] = useState(false)
   const [status, setStatus] = useState<LoginStatus>("idle")
   const [eyeOffset, setEyeOffset] = useState({ x: 0, y: 0 })
+  const autoFeishuAttemptedRef = useRef(false)
 
   useEffect(() => {
     let cancelled = false
@@ -63,6 +82,16 @@ export default function LoginPage() {
   const feishuEnabled = Boolean(authConfig?.feishu_enabled)
   const passwordEnabled = authConfig?.password_enabled ?? true
 
+  useEffect(() => {
+    if (!feishuEnabled || status !== "idle" || autoFeishuAttemptedRef.current || !isFeishuClient()) return
+    const attemptKey = `skg-feishu-auto-login:${nextPath}`
+    if (window.sessionStorage.getItem(attemptKey) === "1") return
+    window.sessionStorage.setItem(attemptKey, "1")
+    autoFeishuAttemptedRef.current = true
+    setStatus("loading")
+    window.location.href = `/api/auth/feishu/start?next=${encodeURIComponent(nextPath)}`
+  }, [feishuEnabled, nextPath, status])
+
   const mood: LoginCharacterMood = useMemo(() => {
     if (status === "success") return "success"
     if (hasError) return "error"
@@ -92,7 +121,7 @@ export default function LoginPage() {
       }
       setStatus("success")
       window.setTimeout(() => {
-        window.location.href = "/"
+        window.location.href = nextPath
       }, 420)
     } catch {
       setStatus("idle")
@@ -102,7 +131,7 @@ export default function LoginPage() {
 
   function onFeishuLogin() {
     setStatus("loading")
-    window.location.href = "/api/auth/feishu/start?next=/"
+    window.location.href = `/api/auth/feishu/start?next=${encodeURIComponent(nextPath)}`
   }
 
   return (