"use client";

import { useState, useEffect, Suspense } from "react";
import { useSearchParams, 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 { api } from "@/lib/api";

function VerifyEmailForm() {
  const router = useRouter();
  const searchParams = useSearchParams();
  const email = searchParams.get("email") || "";

  const [code, setCode] = useState("");
  const [error, setError] = useState("");
  const [loading, setLoading] = useState(false);
  const [success, setSuccess] = useState(false);
  const [resendCountdown, setResendCountdown] = useState(0);

  useEffect(() => {
    if (resendCountdown > 0) {
      const timer = setTimeout(() => setResendCountdown((c) => c - 1), 1000);
      return () => clearTimeout(timer);
    }
  }, [resendCountdown]);

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!email) {
      setError("邮箱地址无效");
      return;
    }
    setLoading(true);
    setError("");
    try {
      await api.auth.verifyEmail(email, code);
      setSuccess(true);
      setTimeout(() => {
        router.push("/login");
      }, 1500);
    } catch (err: unknown) {
      const message = err instanceof Error ? err.message : "验证失败";
      setError(message);
    } finally {
      setLoading(false);
    }
  };

  const handleResend = async () => {
    if (!email || resendCountdown > 0) return;
    setError("");
    try {
      await api.auth.resendVerification(email);
      setResendCountdown(60);
    } catch (err: unknown) {
      const message = err instanceof Error ? err.message : "发送失败";
      setError(message);
    }
  };

  if (success) {
    return (
      <Card className="w-full max-w-md">
        <CardHeader className="space-y-1">
          <CardTitle className="text-2xl">验证成功</CardTitle>
          <CardDescription>邮箱验证成功，正在跳转到登录页...</CardDescription>
        </CardHeader>
        <CardFooter>
          <Link href="/login" className="text-sm text-primary hover:underline">
            立即登录
          </Link>
        </CardFooter>
      </Card>
    );
  }

  return (
    <Card className="w-full max-w-md">
      <CardHeader className="space-y-1">
        <CardTitle className="text-2xl">验证邮箱</CardTitle>
        <CardDescription>
          我们已向 <span className="font-medium">{email || "您的邮箱"}</span> 发送了验证码
        </CardDescription>
      </CardHeader>
      <form onSubmit={handleSubmit}>
        <CardContent className="space-y-4">
          {error && (
            <p className="text-sm text-destructive">{error}</p>
          )}
          <div className="space-y-2">
            <Label htmlFor="code">验证码</Label>
            <Input
              id="code"
              type="text"
              placeholder="请输入6位验证码"
              maxLength={6}
              value={code}
              onChange={(e) => setCode(e.target.value)}
              required
            />
          </div>
          <div className="flex items-center justify-between">
            <Button
              type="button"
              variant="outline"
              size="sm"
              onClick={handleResend}
              disabled={resendCountdown > 0 || !email}
            >
              {resendCountdown > 0
                ? `${resendCountdown} 秒后重新发送`
                : "重新发送验证码"}
            </Button>
          </div>
        </CardContent>
        <CardFooter className="flex flex-col space-y-4">
          <Button type="submit" className="w-full" disabled={loading}>
            {loading ? "验证中..." : "验证"}
          </Button>
          <Link href="/login" className="text-sm text-primary hover:underline">
            返回登录
          </Link>
        </CardFooter>
      </form>
    </Card>
  );
}

export default function VerifyEmailPage() {
  return (
    <Suspense
      fallback={
        <Card className="w-full max-w-md">
          <CardHeader className="space-y-1">
            <CardTitle className="text-2xl">验证邮箱</CardTitle>
            <CardDescription>加载中...</CardDescription>
          </CardHeader>
        </Card>
      }
    >
      <VerifyEmailForm />
    </Suspense>
  );
}