'use client';

import { useState, useEffect, Suspense } from 'react';
import Link from 'next/link';
import { useRouter, useSearchParams } from 'next/navigation';
import { Video, Loader2 } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { signIn } from 'next-auth/react';

function getSafeCallbackUrl(value: string | null): string {
  if (!value) return '/dashboard';
  try {
    const baseOrigin = typeof window === 'undefined' ? 'http://localhost' : window.location.origin;
    const parsed = new URL(value, baseOrigin);
    if (parsed.origin !== baseOrigin) return '/dashboard';
    return `${parsed.pathname}${parsed.search}${parsed.hash}`;
  } catch {
    return '/dashboard';
  }
}

function LoginForm() {
  const router = useRouter();
  const searchParams = useSearchParams();
  const [isLoading, setIsLoading] = useState(false);
  const [error, setError] = useState('');
  const [email, setEmail] = useState('');
  const [password, setPassword] = useState('');
  const [showSuccess, setShowSuccess] = useState(false);
  const callbackUrl = getSafeCallbackUrl(searchParams.get('callbackUrl'));

  useEffect(() => {
    if (searchParams.get('registered') === 'true') {
      setShowSuccess(true);
    }
  }, [searchParams]);

  const handleEmailLogin = async (e: React.FormEvent) => {
    e.preventDefault();
    setIsLoading(true);
    setError('');

    try {
      const result = await signIn('credentials', {
        email,
        password,
        redirect: false,
        callbackUrl,
      });

      if (result?.error) {
        setError('Invalid email or password');
        return;
      }

      const destination = getSafeCallbackUrl(result?.url || callbackUrl);
      router.push(destination);
      router.refresh();
    } catch {
      setError('Something went wrong. Please try again.');
    } finally {
      setIsLoading(false);
    }
  };

  return (
    <Card>
      <CardHeader className="text-center">
        <CardTitle>Welcome back</CardTitle>
        <CardDescription>
          Sign in to your account to continue
        </CardDescription>
      </CardHeader>
      <CardContent>
        {showSuccess && (
          <div className="p-3 rounded-md bg-green-500/10 text-green-600 text-sm mb-4">
            Account created successfully! Please sign in.
          </div>
        )}

        {/* Email Form */}
        <form onSubmit={handleEmailLogin} className="space-y-4">
          <div className="space-y-2">
            <Label htmlFor="email">Email</Label>
            <Input
              id="email"
              type="email"
              placeholder="you@example.com"
              value={email}
              onChange={(e) => {
                setEmail(e.target.value);
                setError('');
              }}
              required
              disabled={isLoading}
            />
          </div>
          <div className="space-y-2">
            <Label htmlFor="password">Password</Label>
            <Input
              id="password"
              type="password"
              placeholder="••••••••"
              value={password}
              onChange={(e) => {
                setPassword(e.target.value);
                setError('');
              }}
              required
              disabled={isLoading}
            />
          </div>

          {error && (
            <div className="p-3 rounded-md bg-destructive/10 text-destructive text-sm">
              {error}
            </div>
          )}

          <Button type="submit" className="w-full" disabled={isLoading}>
            {isLoading && <Loader2 className="h-4 w-4 mr-2 animate-spin" />}
            Sign in
          </Button>
        </form>

        <p className="text-center text-sm text-muted-foreground mt-6">
          Don&apos;t have an account?{' '}
          <Link href="/register" className="text-primary hover:underline">
            Sign up
          </Link>
        </p>
      </CardContent>
    </Card>
  );
}

function LoginFormSkeleton() {
  return (
    <Card>
      <CardHeader className="text-center">
        <CardTitle>Welcome back</CardTitle>
        <CardDescription>
          Sign in to your account to continue
        </CardDescription>
      </CardHeader>
      <CardContent className="space-y-4">
        <div className="h-10 bg-muted animate-pulse rounded-md" />
        <div className="h-10 bg-muted animate-pulse rounded-md" />
        <div className="h-10 bg-primary/20 animate-pulse rounded-md" />
      </CardContent>
    </Card>
  );
}

export default function LoginPage() {
  return (
    <div className="min-h-screen flex items-center justify-center p-4 bg-background">
      <div className="w-full max-w-md">
        {/* Logo */}
        <Link href="/" className="flex items-center justify-center gap-2 mb-8">
          <Video className="h-8 w-8 text-primary" />
          <span className="font-bold text-2xl">OpenFrame</span>
        </Link>

        <Suspense fallback={<LoginFormSkeleton />}>
          <LoginForm />
        </Suspense>

        <p className="text-center text-xs text-muted-foreground mt-4">
          By continuing, you agree to our Terms of Service and Privacy Policy
        </p>
      </div>
    </div>
  );
}