" in theme headers throws
// an uncaught exception that the global handler renders as "Server Error"
// mid-document. Guarantee the constant exists.
if (!defined('THEME_VERSION')) define('THEME_VERSION', '1.0.0');

// Auto-seed default settings (runs once, cached)
ensure_default_settings();

// Auto-create missing AI tables + seo_meta/users/contact_messages columns
// (runs once per schema version bump, cached). Self-heals old installs.
if (function_exists('ensure_required_tables')) { ensure_required_tables(); }

// Integrity check — sparse (~2% of requests). The first call to
// IntegrityGuard::fingerprint() also lazily persists the install fingerprint.
// Call is silent on success, logs drift on failure. Never throws.
if (class_exists('IntegrityGuard')) {
    try { IntegrityGuard::maybeVerify(); } catch (\Throwable $e) { /* non-fatal */ }
}

// License heartbeat — sparse (~1% of requests). Rotates the license token
// when it's within 24h of expiry. Network failure is silent; cached token
// continues to work until expiry, then degradation kicks in.
if (class_exists('LicenseEnforcer') && rand(1, 100) === 42) {
    try { LicenseEnforcer::heartbeat(); } catch (\Throwable $e) {}
}

// AI bulk worker tick — 2% of requests drives one queue item. Cron is
// the primary driver; this web-side tick ensures progress on hosts with
// no cron (shared hosting) without flooding Gemini's rate limits.
if (class_exists('AI_BulkJobManager') && rand(1, 50) === 11) {
    try {
        $mgr = new AI_BulkJobManager();
        $mgr->resumePausedJobs();
        $mgr->processBatch(1);
    } catch (\Throwable $e) {}
}

// Process scheduled posts
if (rand(1, 100) === 1) { // 1% chance on each request
    processScheduledPosts();
    publishDueContentQueueItems();
}

/**
 * Process scheduled posts that are due
 */
function processScheduledPosts(): void
{
    try {
        $db = db();
        $now = date('Y-m-d H:i:s');

        $scheduledPosts = $db->fetchAll(
            "SELECT p.id, p.title, p.excerpt, p.content FROM posts p WHERE p.status = 'scheduled' AND p.scheduled_at <= :now",
            [':now' => $now]
        );

        foreach ($scheduledPosts as $post) {
            // Generate random view count between 400-3000 for new published posts
            $randomViewCount = rand(400, 3000);

            $db->update(
                'posts',
                [
                    'status' => 'published',
                    'published_at' => $now,
                    'view_count' => $randomViewCount,
                ],
                'id = ?',
                [$post['id']]
            );

            // Auto-fill SEO if empty
            autoFillPostSeo($post['id'], $post);

            log_message("Published scheduled post ID: {$post['id']}", 'info', 'scheduler.log');
        }
    } catch (Exception $e) {
        log_message("Scheduler error: " . $e->getMessage(), 'error', 'scheduler.log');
    }
}

/**
 * Publish due content queue items
 */
function publishDueContentQueueItems(): void
{
    try {
        if (!class_exists('ContentQueue')) {
            return;
        }
        $queue = new ContentQueue();
        $result = $queue->publishDueItems();
        if ($result['published'] > 0) {
            log_message("Content queue: published {$result['published']} items", 'info', 'scheduler.log');
        }
    } catch (Exception $e) {
        log_message("Content queue error: " . $e->getMessage(), 'error', 'scheduler.log');
    }
}

/**
 * Auto-fill SEO meta for a post if empty
 */
function autoFillPostSeo(int $postId, array $postData): void
{
    $db = db();

    // Check if SEO already exists and has data
    $existing = $db->fetch(
        "SELECT * FROM seo_meta WHERE post_id = ?",
        [$postId]
    );

    // If meta_title is already filled, skip auto-fill
    if ($existing && !empty($existing['meta_title'])) {
        return;
    }

    $title = $postData['title'] ?? '';
    $excerpt = $postData['excerpt'] ?? '';
    $content = $postData['content'] ?? '';

    // Generate meta description from excerpt or content
    $metaDescription = '';
    if (!empty($excerpt)) {
        $metaDescription = mb_substr(strip_tags($excerpt), 0, 160);
    } elseif (!empty($content)) {
        $metaDescription = mb_substr(strip_tags($content), 0, 160);
    }

    // Generate focus keyword from title
    $stopWords = ['ve', 'ile', 'bir', 'bu', 'da', 'de', 'için', 'mi', 'mı', 'mu', 'mü',
        'ne', 'o', 'olan', 'olarak', 'ama', 'fakat', 'ancak', 'çünkü', 'gibi',
        'kadar', 'ki', 'ya', 'veya', 'hem', 'nasıl', 'neden'];
    $words = preg_split('/\s+/', mb_strtolower(strip_tags($title)));
    $keywords = [];
    foreach ($words as $word) {
        $word = trim($word, '.,!?;:"\'-()[]{}');
        if (mb_strlen($word) > 2 && !in_array($word, $stopWords)) {
            $keywords[] = $word;
            if (count($keywords) >= 3) break;
        }
    }
    $focusKeyword = implode(' ', $keywords);

    $seoData = [
        'post_id' => $postId,
        'meta_title' => $title,
        'meta_description' => $metaDescription,
        'focus_keyword' => $focusKeyword,
        'og_title' => $title,
        'og_description' => $metaDescription
    ];

    if ($existing) {
        $db->update('seo_meta', $seoData, 'post_id = ?', [$postId]);
    } else {
        $db->insert('seo_meta', $seoData);
    }
}
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