Prevent duplicate BuddyPress group names

gistfile1.txt

/**
 * Check if the given BuddyPress group name is duplicate. A group with same name already exists.
 * 
 * @abstract https://buddydev.com/prevent-duplicate-buddypress-group-names/
 * @since 1.0.0
 * @param string $name name to be checked.
 * @param int $group_id group id(exclude this group from test).
 *
 * @return bool
 */
function systmp_bp_duplicate_group_name($name, $group_id = 0)
{
	global $wpdb;
	$bp    = buddypress();
	$table = $bp->groups->table_name;

	$sql = $wpdb->prepare("SELECT id FROM {$table} WHERE name = %s", $name);
	// except this group, used for updating.
	if ($group_id) {
		$sql .= $wpdb->prepare(" AND id != %d", $group_id);
	}

	return $wpdb->get_var($sql);
}

/**
 * On BuddyPress Group Creation, Prevent duplicate group name.
 * 
 * @abstract https://buddydev.com/prevent-duplicate-buddypress-group-names/
 */
function systmp_bp_check_duplicate_group_name_create()
{

	// If we're not at domain.org/groups/create/ then return false.
	if (!bp_is_groups_component() || !bp_is_current_action('create')) {
		return;
	}

	// If no current step is set, reset everything so we can start a fresh group creation.
	buddypress()->groups->current_create_step = bp_action_variable(1);

	if ('group-details' != bp_get_groups_current_create_step()) {
		return;
	}

	if (empty($_POST['group-name'])) {
		return;
	}

	// duplicate.
	if (systmp_bp_duplicate_group_name($_POST['group-name'])) {
		bp_core_add_message(__('Please use a different name.'), 'error');
		bp_core_redirect(trailingslashit(bp_get_groups_directory_permalink() . 'create/step/' . bp_get_groups_current_create_step()));
	}
}

add_action('bp_actions', 'systmp_bp_check_duplicate_group_name_create', 9);

/**
 * On BuddyPress Group Creation, Prevent duplicate group name.
 * 
 * @abstract https://buddydev.com/prevent-duplicate-buddypress-group-names/
 */
function systmp_bp_check_duplicate_group_name_update()
{

	if (!function_exists('bp_get_group_current_admin_tab') || 'edit-details' != bp_get_group_current_admin_tab()) {
		return;
	}

	if (empty($_POST['group-name'])) {
		return;
	}

	// duplicate.
	if (systmp_bp_duplicate_group_name($_POST['group-name'], $_POST['group-id'])) {
		bp_core_add_message(__('Please use a different name.'), 'error');
		bp_core_redirect(bp_get_group_permalink(groups_get_current_group()) . 'admin/edit-details/');
	}
}

add_action('bp_screens', 'systmp_bp_check_duplicate_group_name_update', 9);