import { useState, type FormEvent, type ReactElement } from 'react';
import { Link, useNavigate } from 'react-router-dom';
import { signUp } from '@/lib/auth-client';

export function RegisterPage(): ReactElement {
  const navigate = useNavigate();
  const [error, setError] = useState<string | null>(null);
  const [loading, setLoading] = useState(false);

  async function handleSubmit(event: FormEvent<HTMLFormElement>): Promise<void> {
    event.preventDefault();
    setError(null);
    setLoading(true);

    const form = new FormData(event.currentTarget);
    const name = String(form.get('name') ?? '');
    const email = String(form.get('email') ?? '');
    const password = String(form.get('password') ?? '');

    try {
      const result = await signUp.email({ name, email, password });

      if (result.error) {
        setError(result.error.message ?? 'Registration failed');
        return;
      }

      navigate('/chat', { replace: true });
    } catch (caught: unknown) {
      setError(caught instanceof Error ? caught.message : 'Registration failed');
    } finally {
      setLoading(false);
    }
  }

  return (
    <div>
      <h1 className="text-2xl font-semibold">Create account</h1>
      <p className="mt-1 text-sm text-text-secondary">Get started with Mosaic</p>

      {error ? (
        <div
          role="alert"
          className="mt-4 rounded-lg border border-error/30 bg-error/10 px-4 py-3 text-sm text-error"
        >
          {error}
        </div>
      ) : null}

      <form className="mt-6 space-y-4" onSubmit={handleSubmit}>
        <div>
          <label htmlFor="name" className="block text-sm font-medium text-text-secondary">
            Name
          </label>
          <input
            id="name"
            name="name"
            type="text"
            autoComplete="name"
            required
            disabled={loading}
            className="mt-1 block w-full rounded-lg border border-surface-border bg-surface-elevated px-3 py-2 text-sm text-text-primary placeholder:text-text-muted focus:border-blue-500 focus:outline-none focus:ring-1 focus:ring-blue-500 disabled:opacity-50"
            placeholder="Your name"
          />
        </div>

        <div>
          <label htmlFor="email" className="block text-sm font-medium text-text-secondary">
            Email
          </label>
          <input
            id="email"
            name="email"
            type="email"
            autoComplete="email"
            required
            disabled={loading}
            className="mt-1 block w-full rounded-lg border border-surface-border bg-surface-elevated px-3 py-2 text-sm text-text-primary placeholder:text-text-muted focus:border-blue-500 focus:outline-none focus:ring-1 focus:ring-blue-500 disabled:opacity-50"
            placeholder="you@example.com"
          />
        </div>

        <div>
          <label htmlFor="password" className="block text-sm font-medium text-text-secondary">
            Password
          </label>
          <input
            id="password"
            name="password"
            type="password"
            autoComplete="new-password"
            required
            disabled={loading}
            className="mt-1 block w-full rounded-lg border border-surface-border bg-surface-elevated px-3 py-2 text-sm text-text-primary placeholder:text-text-muted focus:border-blue-500 focus:outline-none focus:ring-1 focus:ring-blue-500 disabled:opacity-50"
            placeholder="••••••••"
          />
        </div>

        <button
          type="submit"
          disabled={loading}
          className="w-full rounded-lg bg-blue-600 px-4 py-2.5 text-sm font-medium text-white transition-colors hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-blue-500 focus:ring-offset-2 focus:ring-offset-surface-card disabled:opacity-50"
        >
          {loading ? 'Creating account...' : 'Create account'}
        </button>
      </form>

      <p className="mt-4 text-center text-sm text-text-muted">
        Already have an account?{' '}
        <Link to="/login" className="text-blue-400 hover:text-blue-300">
          Sign in
        </Link>
      </p>
    </div>
  );
}