'use client';

/**
 * Password gate — shown when accessing a protected album/subpage.
 * Submits to /api/auth and refreshes on success.
 */

import { useState } from 'react';
import Link from 'next/link';
import styles from './PasswordGate.module.css';
import { useDictionary } from './I18nProvider';

interface PasswordGateProps {
  slug: string;
  title: string;
  type?: 'subpage' | 'album' | 'journal' | 'page' | 'site';
  /**
   * Links shown under the card. The site gate passes its legal pages here,
   * which a locked site still serves (proxy.ts, UNGATED_PAGES).
   */
  legalLinks?: { href: string; label: string }[];
}

/** Whole seconds from a `Retry-After` header, or null when there is none. */
function retryAfterSeconds(res: Response): number | null {
  const seconds = Number.parseInt(res.headers.get('retry-after') ?? '', 10);
  return Number.isFinite(seconds) && seconds > 0 ? seconds : null;
}

export default function PasswordGate({
  slug,
  title,
  type = 'subpage',
  legalLinks = [],
}: PasswordGateProps) {
  const t = useDictionary();
  const [password, setPassword] = useState('');
  const [error, setError] = useState('');
  const [loading, setLoading] = useState(false);

  async function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    setError('');
    setLoading(true);

    try {
      const res = await fetch('/api/auth', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ slug, password, type }),
      });

      if (res.ok) {
        window.location.reload();
      } else if (res.status === 401) {
        setError(t.password.incorrect);
        setPassword('');
      } else if (res.status === 429) {
        // The limit says nothing about the password, which may well be right:
        // keep it in the field and say when the next attempt will be heard.
        setError(t.password.tooManyAttempts(retryAfterSeconds(res)));
      } else {
        setError(t.password.failed);
      }
    } catch {
      setError(t.password.failed);
    } finally {
      setLoading(false);
    }
  }

  return (
    <div className={styles.gate}>
      <div className={styles.card}>
        <h2 className={styles.title}>{title}</h2>
        <p className={styles.subtitle}>
          {type === 'site'
            ? t.password.siteSubtitle
            : type === 'page'
              ? t.password.pageSubtitle
              : type === 'journal'
                ? t.password.journalSubtitle
                : t.password.subtitle}
        </p>

        <form onSubmit={handleSubmit} className={styles.form}>
          <input
            id="password-input"
            type="password"
            value={password}
            onChange={(e) => setPassword(e.target.value)}
            placeholder={t.password.placeholder}
            aria-label={t.password.placeholder}
            className={styles.input}
            autoFocus
            required
            disabled={loading}
            aria-invalid={!!error}
            aria-describedby={error ? 'password-error' : undefined}
          />
          <button type="submit" className={styles.button} disabled={loading}>
            {loading ? (
              <>
                <svg
                  aria-hidden="true"
                  width="16"
                  height="16"
                  viewBox="0 0 24 24"
                  fill="none"
                  stroke="currentColor"
                  strokeWidth="2"
                  strokeLinecap="round"
                  strokeLinejoin="round"
                  className={styles.spinner}
                >
                  <circle cx="12" cy="12" r="10" strokeOpacity="0.25"></circle>
                  <path d="M12 2a10 10 0 0 1 10 10"></path>
                </svg>
                {t.password.verifying}
              </>
            ) : (
              t.password.submit
            )}
          </button>
        </form>

        {error && (
          <p id="password-error" className={styles.error} role="alert" aria-live="polite">
            {error}
          </p>
        )}
      </div>
      {legalLinks.length > 0 && (
        <nav className={styles.legal} aria-label={t.password.legalNavAria}>
          {legalLinks.map(({ href, label }) => (
            <Link key={href} href={href} className="footer__legal-link">
              {label}
            </Link>
          ))}
        </nav>
      )}
    </div>
  );
}