Posts relacionados por taxonomía (Bricks Query Editor PHP)

return (function () {

  /**
   * CONFIG
   */
  $cfg = [
    // Post type(s) que quieres listar como “relacionados”
    // Ej: 'post' | 'product' | 'mi_cpt' | ['post','mi_cpt']
    'target_post_type'  => 'post',

    // Taxonomías por las que quieres relacionar (slug REAL)
    // Ej: ['category'] | ['post_tag'] | ['mi_taxonomia']
    'taxonomies'        => ['TU_TAXONOMIA_AQUI'],

    // Número de resultados
    'posts_per_page'    => 4,

    // Excluir el “actual”:
    // - true/false
    // - 'auto' => solo excluye si el single actual es del mismo post_type que el target
    'exclude_current'   => 'auto',

    // Coincidencia entre taxonomías:
    // - 'any' => OR: comparte cualquiera (más flexible)
    // - 'all' => AND: debe cumplir todas (más estricto)
    'match'             => 'any',

    // Si el post “source” no tiene términos detectables:
    // - 'none'   => no muestra nada (recomendado para related)
    // - 'latest' => muestra últimos del target_post_type
    'fallback'          => 'none',

    // Incluir hijos (categorías hijas, etc.)
    // Si te trae “demasiados”, ponlo a false
    'include_children'  => true,

    // Orden
    'orderby'           => 'date', // o 'rand'
    'order'             => 'DESC',

    // Debug visible (solo admins + ?rel_debug=1)
    'debug'             => false,
    'debug_key'         => 'rel_debug',
    'debug_cap'         => 'manage_options',
    'debug_global_key'  => 'FLOW_RELATED_DEBUG',
  ];

  /**
   * 1) Determinar el source_id (el contenido del single)
   */
  $source_id = (int) get_queried_object_id();
  if (!$source_id) $source_id = (int) get_the_ID();

  $source_pt = $source_id ? get_post_type($source_id) : null;

  /**
   * 2) exclude_current en modo auto
   */
  $target_types = (array) $cfg['target_post_type'];

  $exclude = $cfg['exclude_current'];
  if ($exclude === 'auto') {
    $exclude = ($source_pt && in_array($source_pt, $target_types, true));
  } else {
    $exclude = (bool) $exclude;
  }

  /**
   * 3) Construir tax_query según términos del source
   */
  $tax_query_parts = [];
  $debug_terms = [];

  foreach ((array) $cfg['taxonomies'] as $tax) {
    $tax = (string) $tax;

    if (!taxonomy_exists($tax)) {
      $debug_terms[$tax] = ['error' => 'taxonomy_not_exists'];
      continue;
    }

    // El target post_type debe soportar esa taxonomía
    $tax_in_target = false;
    foreach ($target_types as $pt) {
      if (is_object_in_taxonomy($pt, $tax)) {
        $tax_in_target = true;
        break;
      }
    }
    if (!$tax_in_target) {
      $debug_terms[$tax] = ['error' => 'taxonomy_not_in_target_post_type'];
      continue;
    }

    $term_ids = wp_get_post_terms($source_id, $tax, ['fields' => 'ids']);

    if (is_wp_error($term_ids) || empty($term_ids)) {
      $debug_terms[$tax] = ['terms' => []];
      continue;
    }

    $term_ids = array_map('intval', $term_ids);
    $debug_terms[$tax] = ['terms' => $term_ids];

    $tax_query_parts[] = [
      'taxonomy'         => $tax,
      'field'            => 'term_id',
      'terms'            => $term_ids,
      'operator'         => 'IN',
      'include_children' => (bool) $cfg['include_children'],
    ];
  }

  /**
   * 4) Args base
   */
  $args = [
    'post_type'      => $cfg['target_post_type'],
    'post_status'    => 'publish',
    'posts_per_page' => (int) $cfg['posts_per_page'],
    'orderby'        => $cfg['orderby'],
    'order'          => $cfg['order'],
    'no_found_rows'  => true,
  ];

  if ($exclude && $source_id) {
    $args['post__not_in'] = [$source_id];
  }

  if (!empty($tax_query_parts)) {
    $args['tax_query'] = array_merge(
      ['relation' => ($cfg['match'] === 'all' ? 'AND' : 'OR')],
      $tax_query_parts
    );
  } else {
    // Sin términos -> fallback
    if ($cfg['fallback'] === 'none') {
      $args['post__in'] = [0];
    }
  }

  /**
   * 5) Debug (opcional) -> lo imprime un Code element aparte
   */
  if (!empty($cfg['debug']) && current_user_can($cfg['debug_cap']) && !empty($_GET[$cfg['debug_key']])) {
    $test_args = $args;
    $test_args['fields'] = 'ids';
    $test_args['posts_per_page'] = 20;

    $GLOBALS[$cfg['debug_global_key']] = [
      'source_id'        => $source_id,
      'source_post_type' => $source_pt,
      'target_post_type' => $cfg['target_post_type'],
      'exclude_current'  => $exclude,
      'taxonomies'       => $cfg['taxonomies'],
      'terms_found'      => $debug_terms,
      'final_args'       => $args,
      'test_ids'         => get_posts($test_args),
    ];
  }

  return $args;

})();


/* Codigo para debug. ---------
   Poner con el widget de codigo */

<?php
if (!current_user_can('manage_options') || empty($_GET['rel_debug'])) return;

echo '<div style="padding:16px;border:1px solid #ddd;background:#fff;margin:16px 0">';
echo '<strong>FLOW_RELATED_DEBUG</strong>';
echo '<pre style="margin-top:12px;white-space:pre-wrap;">';
print_r($GLOBALS['FLOW_RELATED_DEBUG'] ?? []);
echo '</pre></div>';
?>