'use client';

import { useState } from 'react';
import { useRouter } from 'next/navigation';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Alert, AlertDescription } from '@/components/ui/alert';
import Loader2 from 'lucide-react/dist/esm/icons/loader-2';
import Eye from 'lucide-react/dist/esm/icons/eye';
import EyeOff from 'lucide-react/dist/esm/icons/eye-off';
import { signInWithEmail } from '@/lib/supabase';

export function SignInForm() {
  const [email, setEmail] = useState('');
  const [password, setPassword] = useState('');
  const [showPassword, setShowPassword] = useState(false);
  const [isLoading, setIsLoading] = useState(false);
  const [error, setError] = useState('');
  const router = useRouter();

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

    try {
      const { data, error } = await signInWithEmail(email, password);
      
      if (error) {
        if (error.message.includes('Invalid login credentials')) {
          setError('Invalid email or password. Please try again.');
        } else if (error.message.includes('Email not confirmed')) {
          setError('Please check your email and click the confirmation link before signing in.');
        } else {
          setError(error.message);
        }
        return;
      }

      if (data.user) {
        const role = data.user.app_metadata?.role === 'admin' ? 'admin' : 'user';
        router.push(role === 'admin' ? '/admin' : '/user');
        router.refresh();
      }
    } catch {
      setError('An unexpected error occurred. Please try again.');
    } finally {
      setIsLoading(false);
    }
  };

  return (
    <Card className="w-full max-w-md mx-auto border-futuristic">
      <CardHeader className="space-y-1">
        <CardTitle className="text-2xl font-bold text-center">Welcome back</CardTitle>
        <CardDescription className="text-center text-muted-foreground">
          Sign in to your account to continue
        </CardDescription>
      </CardHeader>
      <CardContent>
        <p className="mb-4 rounded-md border border-border/60 bg-muted/40 px-3 py-2 text-center text-xs text-muted-foreground">
          Admins are redirected to <span className="font-medium text-foreground">/admin</span>, users to{' '}
          <span className="font-medium text-foreground">/user</span>. Promote a user by setting{' '}
          <code className="rounded bg-muted px-1 py-0.5">app_metadata.role = &quot;admin&quot;</code> in Supabase,
          then sign in again.
        </p>
        <form onSubmit={handleSubmit} className="space-y-4">
          {error && (
            <Alert variant="destructive">
              <AlertDescription>{error}</AlertDescription>
            </Alert>
          )}
          
          <div className="space-y-2">
            <Label htmlFor="email">Email</Label>
            <Input
              id="email"
              type="email"
              placeholder="Enter your email"
              value={email}
              onChange={(e) => setEmail(e.target.value)}
              required
              disabled={isLoading}
              className="border-futuristic"
            />
          </div>
          
          <div className="space-y-2">
            <Label htmlFor="password">Password</Label>
            <div className="relative">
              <Input
                id="password"
                type={showPassword ? 'text' : 'password'}
                placeholder="Enter your password"
                value={password}
                onChange={(e) => setPassword(e.target.value)}
                required
                disabled={isLoading}
                className="border-futuristic pr-10"
              />
              <Button
                type="button"
                variant="ghost"
                size="sm"
                className="absolute right-0 top-0 h-full px-3 py-2 hover:bg-transparent"
                onClick={() => setShowPassword(!showPassword)}
                disabled={isLoading}
              >
                {showPassword ? (
                  <EyeOff className="h-4 w-4 text-muted-foreground" />
                ) : (
                  <Eye className="h-4 w-4 text-muted-foreground" />
                )}
              </Button>
            </div>
          </div>
          
          <Button
            type="submit"
            className="w-full border-futuristic"
            variant="futuristic"
            disabled={isLoading}
          >
            {isLoading ? (
              <>
                <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                Signing in...
              </>
            ) : (
              'Sign In'
            )}
          </Button>
        </form>
        
        <div className="mt-6 text-center text-sm">
          <span className="text-muted-foreground">Don't have an account? </span>
          <Button
            variant="link"
            className="p-0 h-auto text-futuristic hover:text-futuristic/80"
            onClick={() => router.push('/sign-up')}
          >
            Sign up
          </Button>
        </div>
      </CardContent>
    </Card>
  );
}