Elixir Ecto paginate Query with callback

ecto_paginate_query.ex

defmodule MyEcto do

    # Helper to paginate a query
    def paginate_query(%Ecto.Query{} = query, per_page, current_page, callback) when per_page > 0 and current_page >= 0 and is_function(callback) do
      import Ecto.Query
      offset = per_page * current_page
      query
      |> limit(^per_page)
      |> offset(^offset)
      |> LongRepo.all()
      |> case do
        [] ->
          :ok
        results ->
          Enum.each(results, &(callback.(&1)))
          if(length(results) >= per_page) do
            paginate_query(query, per_page, current_page+1, callback)
          else
            :ok
          end
      end
    end

end