fix email login

app/auth/signin/page.tsx

@@ -1,7 +1,8 @@
 "use client"
 
-import { useState } from "react"
-import { signIn, getProviders } from "next-auth/react"
+import { useState, useEffect } from "react"
+import { signIn, getProviders, useSession } from "next-auth/react"
+import { useRouter, useSearchParams } from "next/navigation"
 import { Button } from "@/components/ui/button"
 import { Input } from "@/components/ui/input"
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card"
@@ -14,6 +15,38 @@ export default function SignInPage() {
   const [email, setEmail] = useState("")
   const [isLoading, setIsLoading] = useState(false)
   const [message, setMessage] = useState("")
+  const { data: session, status } = useSession()
+  const router = useRouter()
+  const searchParams = useSearchParams()
+
+  // 检查用户是否已登录，如果已登录则重定向
+  useEffect(() => {
+    if (status === "authenticated" && session) {
+      const callbackUrl = searchParams.get("callbackUrl") || "/"
+      router.push(callbackUrl)
+    }
+  }, [status, session, router, searchParams])
+
+  // 如果正在加载会话状态，显示loading
+  if (status === "loading") {
+    return (
+      <div className="min-h-screen flex items-center justify-center bg-gray-50">
+        <Card className="w-full max-w-md">
+          <CardContent className="flex items-center justify-center p-6">
+            <div className="text-center">
+              <div className="w-8 h-8 bg-gray-200 rounded-full animate-pulse mx-auto mb-2"></div>
+              <p className="text-sm text-muted-foreground">正在检查登录状态...</p>
+            </div>
+          </CardContent>
+        </Card>
+      </div>
+    )
+  }
+
+  // 如果已经登录，不显示登录表单（虽然会重定向，但防止闪烁）
+  if (status === "authenticated") {
+    return null
+  }
 
   const handleEmailSignIn = async (e: React.FormEvent) => {
     e.preventDefault()
@@ -41,7 +74,8 @@ export default function SignInPage() {
   const handleGoogleSignIn = async () => {
     setIsLoading(true)
     try {
-      await signIn("google", { callbackUrl: "/" })
+      const callbackUrl = searchParams.get("callbackUrl") || "/"
+      await signIn("google", { callbackUrl })
     } catch (error) {
       setMessage("Google登录失败，请重试")
       setIsLoading(false)

auth.ts

@@ -11,6 +11,7 @@ export const { auth, handlers, signIn, signOut } = NextAuth({
     Google({
       clientId: process.env.GOOGLE_CLIENT_ID!,
       clientSecret: process.env.GOOGLE_CLIENT_SECRET!,
+      allowDangerousEmailAccountLinking: true,
     }),
     Nodemailer({
       server: {
@@ -28,13 +29,77 @@ export const { auth, handlers, signIn, signOut } = NextAuth({
     signIn: "/auth/signin",
     error: "/auth/error",
   },
+  events: {
+    async linkAccount({ user, account, profile }) {
+      if (profile?.email && user.id) {
+        await db.user.update({
+          where: { id: user.id },
+          data: {
+            email: profile.email,
+            name: profile.name || user.name,
+            image: (profile as any)?.picture || user.image,
+            emailVerified: (profile as any)?.email_verified ? new Date() : null,
+          },
+        })
+      }
+    },
+  },
   callbacks: {
+    async signIn({ user, account, profile, email, credentials }) {
+      if (!user.email) return false
+
+      if (account?.provider === "nodemailer") {
+        return true
+      }
+
+      if (account?.provider === "google" && user.email) {
+        const existingUser = await db.user.findUnique({
+          where: { email: user.email },
+          include: { accounts: true },
+        })
+
+        if (existingUser) {
+          const hasGoogleAccount = existingUser.accounts.some(
+            acc => acc.provider === "google"
+          )
+
+          if (!hasGoogleAccount) {
+            await db.account.create({
+              data: {
+                userId: existingUser.id,
+                type: account.type,
+                provider: account.provider,
+                providerAccountId: account.providerAccountId,
+                refresh_token: account.refresh_token as string | null,
+                access_token: account.access_token as string | null,
+                expires_at: account.expires_at,
+                token_type: account.token_type,
+                scope: account.scope,
+                id_token: account.id_token as string | null,
+                session_state: account.session_state as string | null,
+              },
+            })
+
+            await db.user.update({
+              where: { id: existingUser.id },
+              data: {
+                name: profile?.name || existingUser.name,
+                image: (profile as any)?.picture || existingUser.image,
+                emailVerified: (profile as any)?.email_verified ? new Date() : existingUser.emailVerified,
+              },
+            })
+          }
+        }
+      }
+
+      return true
+    },
     async session({ token, session }) {
       if (token) {
-        session.user.id = token.id
-        session.user.name = token.name
-        session.user.email = token.email
-        session.user.image = token.picture
+        session.user.id = token.id as string
+        session.user.name = token.name as string
+        session.user.email = token.email as string
+        session.user.image = token.picture as string
       }
 
       return session
@@ -42,7 +107,7 @@ export const { auth, handlers, signIn, signOut } = NextAuth({
     async jwt({ user, token }) {
       const dbUser = await db.user.findFirst({
         where: {
-          email: token.email,
+          email: token.email!,
         },
       })