"use client"

import { useState } from "react"
import { signIn, signOut } from "next-auth/react"
import { useRouter } from "next/navigation"
import Link from "next/link"
import { Button } from "@/components/ui/button"
import { Input } from "@/components/ui/input"
import { Label } from "@/components/ui/label"
import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card"
import { Alert, AlertDescription } from "@/components/ui/alert"
import { BookOpen } from "lucide-react"

export default function SignInPage() {
  const router = useRouter()
  const [email, setEmail] = useState("")
  const [password, setPassword] = useState("")
  const [error, setError] = useState("")
  const [loading, setLoading] = useState(false)

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()
    setError("")
    setLoading(true)

    try {
      // 先退出登录，清除旧的 session
      await signOut({ redirect: false })
      
      // 等待一小段时间确保 session 被清除
      await new Promise(resolve => setTimeout(resolve, 500))
      
      // 清除所有 localStorage 和 sessionStorage
      localStorage.clear()
      sessionStorage.clear()
      
      // 然后重新登录
      const result = await signIn("credentials", {
        email,
        password,
        redirect: false,
      })

      if (result?.error) {
        setError("邮箱或密码错误")
        setLoading(false)
      } else {
        // 强制完全刷新页面，清除所有缓存
        window.location.replace("/")
      }
    } catch (err) {
      setError("登录失败，请稍后重试")
      setLoading(false)
    }
  }

  return (
    <div className="min-h-screen flex items-center justify-center bg-gradient-to-br from-primary/5 via-background to-secondary/5 p-4">
      <Card className="w-full max-w-md">
        <CardHeader className="space-y-1 text-center">
          <div className="flex justify-center mb-4">
            <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-primary text-primary-foreground">
              <BookOpen className="h-7 w-7" />
            </div>
          </div>
          <CardTitle className="text-2xl font-serif">登录</CardTitle>
          <CardDescription>
            登录到华夏谱家族树系统
          </CardDescription>
        </CardHeader>
        <form onSubmit={handleSubmit}>
          <CardContent className="space-y-4">
            {error && (
              <Alert variant="destructive">
                <AlertDescription>{error}</AlertDescription>
              </Alert>
            )}
            
            <div className="space-y-2">
              <Label htmlFor="email">邮箱</Label>
              <Input
                id="email"
                type="email"
                placeholder="请输入邮箱"
                value={email}
                onChange={(e) => setEmail(e.target.value)}
                required
                disabled={loading}
                autoComplete="off"
              />
            </div>
            
            <div className="space-y-2">
              <Label htmlFor="password">密码</Label>
              <Input
                id="password"
                type="password"
                placeholder="••••••••"
                value={password}
                onChange={(e) => setPassword(e.target.value)}
                required
                disabled={loading}
                autoComplete="new-password"
              />
            </div>
          </CardContent>
          
          <CardFooter className="flex flex-col space-y-4 pt-6">
            <Button 
              type="submit" 
              className="w-full"
              disabled={loading}
            >
              {loading ? "登录中..." : "登录"}
            </Button>
            
            <div className="text-sm text-center text-muted-foreground">
              还没有账号？{" "}
              <Link href="/auth/register" className="text-primary hover:underline">
                立即注册
              </Link>
            </div>
          </CardFooter>
        </form>
      </Card>
    </div>
  )
}