module Pagy::ItemsExtra::BackendAddOn

def pagy_get_items_size(vars)
  params[vars[:items_param] || DEFAULT[:items_param]]
end

def pagy_set_items_from_params(vars)
  return if vars[:items]                                                             # :items explicitly set
  return unless vars.key?(:items_extra) ? vars[:items_extra] : DEFAULT[:items_extra] # :items_extra is false
  return unless (items_count = pagy_get_items_size(vars))                            # no items from request params
  vars[:items] = [items_count.to_i, vars.key?(:max_items) ? vars[:max_items] : DEFAULT[:max_items]].compact.min
end