defmodule Mobilizon.Service.Events.Tool do @moduledoc """ Event-related tools """ alias Mobilizon.Events alias Mobilizon.Events.Event alias Mobilizon.Actors.Actor alias Mobilizon.Users.User alias MobilizonWeb.Email alias Mobilizon.Storage.Repo @important_changes [:title, :begins_on, :ends_on] def calculate_event_diff_and_send_notifications( %Event{} = old_event, %Event{id: event_id} = event, changes ) do important = MapSet.new(@important_changes) diff = changes |> Map.keys() |> MapSet.new() |> MapSet.intersection(important) if MapSet.size(diff) > 0 do Repo.transaction(fn -> event_id |> Events.list_local_emails_user_participants_for_event_query() |> Repo.stream() |> Enum.to_list() |> Enum.each( &send_notification_for_event_update_to_participant(&1, old_event, event, diff) ) end) end end defp send_notification_for_event_update_to_participant( {%Actor{} = actor, %User{} = user}, %Event{} = old_event, %Event{} = event, diff ) do user |> Email.Event.event_updated(actor, old_event, event, diff) |> Email.Mailer.deliver_later() end end