<?php
declare(strict_types=1);

/* POLANA NEWSLETTER V1.1 */

function newsletter_db(): PDO {
    if (!function_exists('db')) {
        throw new RuntimeException('Brak funkcji db().');
    }
    $pdo = db();
    if (!$pdo instanceof PDO) throw new RuntimeException('db() nie zwróciło PDO.');
    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    return $pdo;
}

function newsletter_install_table(): void {
    $sql = <<<SQL
CREATE TABLE IF NOT EXISTS newsletter_subscribers (
    id INT UNSIGNED NOT NULL AUTO_INCREMENT,
    email VARCHAR(190) NOT NULL,
    name VARCHAR(150) NULL,
    source VARCHAR(50) NOT NULL DEFAULT 'footer',
    status VARCHAR(20) NOT NULL DEFAULT 'active',
    consent_at DATETIME NOT NULL,
    withdrawn_at DATETIME NULL,
    consent_ip_hash CHAR(64) NULL,
    user_agent VARCHAR(255) NULL,
    unsubscribe_token CHAR(64) NOT NULL,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    PRIMARY KEY (id),
    UNIQUE KEY uq_newsletter_email (email),
    UNIQUE KEY uq_newsletter_token (unsubscribe_token),
    KEY idx_newsletter_status (status),
    KEY idx_newsletter_consent_at (consent_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci
SQL;
    newsletter_db()->exec($sql);
}

function newsletter_email_from_post(): string {
    foreach (['email','reservation_email','guest_email','customer_email'] as $k) {
        $v = trim((string)($_POST[$k] ?? ''));
        if ($v !== '' && filter_var($v, FILTER_VALIDATE_EMAIL)) return mb_strtolower($v,'UTF-8');
    }
    return '';
}

function newsletter_name_from_post(): string {
    foreach (['name','guest_name','customer_name','full_name','fullname','first_name'] as $k) {
        $v = trim((string)($_POST[$k] ?? ''));
        if ($v !== '') return mb_substr($v,0,150,'UTF-8');
    }
    return '';
}

function newsletter_ip_hash(): ?string {
    $ip = trim((string)($_SERVER['REMOTE_ADDR'] ?? ''));
    if ($ip === '') return null;
    return hash('sha256', 'polana-newsletter|' . $ip);
}

function newsletter_subscribe(string $email, string $name='', string $source='footer'): array {
    newsletter_install_table();

    $email = mb_strtolower(trim($email),'UTF-8');
    $name = trim($name);
    $source = trim($source) ?: 'footer';

    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
        return ['ok'=>false,'message'=>'Podaj poprawny adres e-mail.'];
    }

    $pdo = newsletter_db();
    $check = $pdo->prepare('SELECT id, unsubscribe_token FROM newsletter_subscribers WHERE email=:email LIMIT 1');
    $check->execute([':email'=>$email]);
    $row = $check->fetch(PDO::FETCH_ASSOC);

    $token = $row && !empty($row['unsubscribe_token'])
        ? (string)$row['unsubscribe_token']
        : bin2hex(random_bytes(32));

    $ua = mb_substr(trim((string)($_SERVER['HTTP_USER_AGENT'] ?? '')),0,255,'UTF-8');
    $ipHash = newsletter_ip_hash();

    if ($row) {
        $st = $pdo->prepare(
            'UPDATE newsletter_subscribers
             SET name=:name, source=:source, status="active", consent_at=NOW(),
                 withdrawn_at=NULL, consent_ip_hash=:ip, user_agent=:ua,
                 unsubscribe_token=:token
             WHERE id=:id'
        );
        $st->execute([
            ':name'=>$name !== '' ? $name : null,
            ':source'=>$source,
            ':ip'=>$ipHash,
            ':ua'=>$ua !== '' ? $ua : null,
            ':token'=>$token,
            ':id'=>$row['id'],
        ]);
    } else {
        $st = $pdo->prepare(
            'INSERT INTO newsletter_subscribers
             (email,name,source,status,consent_at,consent_ip_hash,user_agent,unsubscribe_token)
             VALUES (:email,:name,:source,"active",NOW(),:ip,:ua,:token)'
        );
        $st->execute([
            ':email'=>$email,
            ':name'=>$name !== '' ? $name : null,
            ':source'=>$source,
            ':ip'=>$ipHash,
            ':ua'=>$ua !== '' ? $ua : null,
            ':token'=>$token,
        ]);
    }

    return ['ok'=>true,'message'=>'Dziękujemy! Jesteś na liście Mojej Polany Smaków.','token'=>$token];
}

function newsletter_unsubscribe(string $token): bool {
    newsletter_install_table();
    if (!preg_match('/^[a-f0-9]{64}$/i',$token)) return false;
    $st = newsletter_db()->prepare(
        'UPDATE newsletter_subscribers
         SET status="unsubscribed", withdrawn_at=NOW()
         WHERE unsubscribe_token=:token'
    );
    $st->execute([':token'=>$token]);
    return $st->rowCount() > 0;
}

function newsletter_handle_reservation_optin(): void {
    if ($_SERVER['REQUEST_METHOD'] !== 'POST') return;
    if (empty($_POST['newsletter_optin'])) return;

    $email = newsletter_email_from_post();
    if ($email === '') return;

    try {
        newsletter_subscribe($email, newsletter_name_from_post(), 'reservation');
    } catch (Throwable $e) {
        error_log('[POLANA NEWSLETTER reservation] '.$e->getMessage());
    }
}

function newsletter_render_footer(): void {
    ?>
    <section class="newsletter-strip" aria-labelledby="newsletter-title">
      <div class="newsletter-strip__inner">
        <div class="newsletter-strip__copy">
          <span class="newsletter-strip__eyebrow">Z Polany prosto do skrzynki</span>
          <h2 id="newsletter-title">Bądź na bieżąco z tym, co dzieje się na Polanie.</h2>
          <p>Nowe menu, sezonowe smaki, wydarzenia i rzeczy, o których warto wiedzieć wcześniej.</p>
        </div>
        <form class="newsletter-strip__form" method="post" action="<?= e(polana_local_path('/newsletter.php')) ?>" autocomplete="on">
          <label class="newsletter-strip__label" for="newsletter-email">Twój e-mail</label>
          <div class="newsletter-strip__row">
            <input id="newsletter-email" type="email" name="email" autocomplete="email" placeholder="[email protected]" required>
            <button type="submit">Zapisz mnie</button>
          </div>
          <label class="newsletter-consent">
            <input type="checkbox" name="newsletter_consent" value="1" required>
            <span>Chcę otrzymywać newsletter Mojej Polany Smaków z informacjami o menu, wydarzeniach i nowościach. Zgoda jest dobrowolna i mogę ją wycofać w każdej chwili.</span>
          </label>
          <input type="hidden" name="source" value="footer">
        </form>
      </div>
    </section>
    <?php
}