module Boards module Lists class CreateService < Boards::BaseService def execute(board) List.transaction do label = available_labels_for(board).find(params[:label_id]) position = next_position(board) create_list(board, label, position) end end private def available_labels_for(board) LabelsFinder.new(current_user, project_id: parent.id).execute end def next_position(board) max_position = board.lists.movable.maximum(:position) max_position.nil? ? 0 : max_position.succ end def create_list(board, label, position) board.lists.create(label: label, list_type: :label, position: position) end end end end