SWELL│目次に対して特定の項目を表示非表示するカスタマイズ

<?php
// ACFのチェックボックス: omit_headings / 戻り値は「値」。
add_filter('acf/load_field/name=omit_headings', function ($field) {
    if (!is_admin()) return $field;
    $id = isset($_GET['post']) ? absint($_GET['post']) : get_the_ID();
    $field['choices'] = [];
    if (!$id) return $field;
    $visited = [];
    $walk = function ($blocks, $depth = 0) use (&$walk, &$field, &$visited) {
        if ($depth >= 8) return;
        foreach ($blocks as $block) {
            if (($block['blockName'] ?? '') === 'core/heading') {
                $level = (int) ($block['attrs']['level'] ?? 2);
                $anchor = $block['attrs']['anchor'] ?? '';
                if (in_array($level, [2, 3], true) && preg_match('/^[A-Za-z][A-Za-z0-9_-]*$/D', $anchor)) {
                    $field['choices'][$anchor] = 'H'.$level.': '.wp_strip_all_tags($block['innerHTML']).' (#'.$anchor.')';
                }
            }
            if (($block['blockName'] ?? '') === 'core/block') {
                $ref = absint($block['attrs']['ref'] ?? 0);
                if ($ref && !isset($visited[$ref])) {
                    $visited[$ref] = true;
                    $shared = get_post($ref);
                    if ($shared && $shared->post_type === 'wp_block' && $shared->post_status === 'publish' && $shared->post_password === '') {
                        $walk(parse_blocks($shared->post_content), $depth + 1);
                    }
                }
            }
            if (!empty($block['innerBlocks'])) $walk($block['innerBlocks'], $depth + 1);
        }
    };
    $walk(parse_blocks(get_post_field('post_content', $id)));
    return $field;
});
add_filter('render_block_core/heading', function ($content, $block) {
    if (is_admin() || !is_singular() || !function_exists('get_field')) return $content;
    $anchor = $block['attrs']['anchor'] ?? '';
    $level = (int) ($block['attrs']['level'] ?? 2);
    if (!in_array($level, [2, 3], true) || !is_string($anchor) || !preg_match('/^[A-Za-z][A-Za-z0-9_-]*$/D', $anchor)) return $content;
    $values = get_field('omit_headings', get_queried_object_id());
    if (!is_array($values) || !in_array($anchor, $values, true)) return $content;
    if (!class_exists('WP_HTML_Tag_Processor')) return $content;
    $html = new WP_HTML_Tag_Processor($content);
    if ($html->next_tag('H'.$level)) $html->add_class('swl-toc-off');
    return $html->get_updated_html();
}, 10, 2);