<?php
function nkf_custom_cache($content){
    $cache_file = WP_CONTENT_DIR.'/cache/page_'.md5($_SERVER['REQUEST_URI']).'.html';
    if(file_exists($cache_file)){
        echo file_get_contents($cache_file);
        exit;
    } else {
        ob_start();
        echo $content;
        $cached = ob_get_contents();
        file_put_contents($cache_file, $cached);
        ob_end_flush();
    }
    return '';
}
add_action('template_redirect', function(){
    if(!is_user_logged_in()) nkf_custom_cache('');
});
?>

<?php
function nkf_video_shortcode($atts){
    $atts = shortcode_atts(['url'=>''], $atts, 'nkf_video');
    if(empty($atts['url'])) return '';
    return '<div style="position:relative; padding-top:56.25%; margin-bottom:20px;">
        <iframe src="'.esc_url($atts['url']).'" style="position:absolute;top:0;left:0;width:100%;height:100%;border:none;" allowfullscreen></iframe>
    </div>';
}
add_shortcode('nkf_video','nkf_video_shortcode');
?>

.table-responsive {
    overflow-x:auto;
}
table {
    border-collapse:collapse;
    width:100%;
}
th, td {
    padding:10px;
    border:1px solid #1e88e5;
    text-align:center;
}
th {
    background:#1e88e5;
    color:#fff;
}

<?php
function nkf_recent_comments($atts){
    $comments = get_comments(['number'=>5,'status'=>'approve']);
    $output = '<ul style="list-style:none;padding:0;">';
    foreach($comments as $c){
        $output .= '<li style="margin-bottom:10px;"><strong>'.esc_html($c->comment_author).'</strong>: '.esc_html($c->comment_content).'</li>';
    }
    $output .= '</ul>';
    return $output;
}
add_shortcode('nkf_recent_comments','nkf_recent_comments');
?>

<?php
function nkf_block_spam_registration($login, $email, $errors){
    if(preg_match('/spamdomain\.com$/', $email)){
        $errors->add('spam_email','لا يمكنك استخدام هذا البريد للتسجيل');
    }
}
add_action('register_post','nkf_block_spam_registration',10,3);
?>

<style>
#nkf-loader {
  position:fixed; top:0; left:0; width:0%; height:4px; background:#1e88e5; z-index:9999; transition:width 0.3s;
}
</style>
<script>
document.addEventListener("DOMContentLoaded", function(){
  var loader = document.createElement('div'); loader.id='nkf-loader'; document.body.appendChild(loader);
  var width=0;
  var interval = setInterval(function(){
      width += 5; loader.style.width=width+'%';
      if(width>=100) clearInterval(interval);
  },50);
});
</script>