private function get_core_forms( $return = 'posts', $use_cache = true ) {

		global $wpdb;

		$forms_cache_key = 'posts' === $return ? 'llms_core_forms' : 'llms_core_form_ids';
		$forms           = $use_cache ? wp_cache_get( $forms_cache_key ) : false;

		if ( false !== $forms ) {
			return $forms;
		}

		$locations              = array_keys( $this->get_locations() );
		$locations_placeholders = implode( ',', array_fill( 0, count( $locations ), '%s' ) );
		$prepare_values         = array_merge( array( $this->get_post_type() ), $locations );

		$query = "
SELECT MIN({$wpdb->posts}.ID) AS ID
FROM $wpdb->posts
INNER JOIN {$wpdb->postmeta} AS locations ON {$wpdb->posts}.ID = locations.post_id AND locations.meta_key='_llms_form_location'
INNER JOIN {$wpdb->postmeta} AS is_cores ON {$wpdb->posts}.ID = is_cores.post_id AND is_cores.meta_key='_llms_form_is_core'
WHERE {$wpdb->posts}.post_type = %s
AND locations.meta_value IN ({$locations_placeholders})
AND is_cores.meta_value = 'yes'
GROUP BY locations.meta_value";

		$form_ids = $wpdb->get_col(
			$wpdb->prepare(
				$query, // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- It is prepared.
				$prepare_values
			)
		);

		$form_ids = array_map( 'absint', $form_ids );
		$forms    = 'post' === $return ? array_map( 'get_post', $form_ids ) : $form_ids;

		wp_cache_set( $forms_cache_key, $forms );

		return $forms;

	}