Move API under GraphQL context

lib/graphql/api/participations.ex

@@ -0,0 +1,68 @@
+defmodule Mobilizon.GraphQL.API.Participations do
+  @moduledoc """
+  Common API to join events and groups.
+  """
+
+  alias Mobilizon.Actors.Actor
+  alias Mobilizon.Events.{Event, Participant}
+
+  alias Mobilizon.Federation.ActivityPub
+
+  alias MobilizonWeb.Email.Participation
+
+  @spec join(Event.t(), Actor.t()) :: {:ok, Participant.t()}
+  def join(%Event{id: event_id} = event, %Actor{id: actor_id} = actor) do
+    with {:error, :participant_not_found} <- Mobilizon.Events.get_participant(event_id, actor_id),
+         {:ok, activity, participant} <- ActivityPub.join(event, actor, true) do
+      {:ok, activity, participant}
+    end
+  end
+
+  def leave(%Event{} = event, %Actor{} = actor) do
+    with {:ok, activity, participant} <- ActivityPub.leave(event, actor, true) do
+      {:ok, activity, participant}
+    end
+  end
+
+  @doc """
+  Update participation status
+  """
+  def update(%Participant{} = participation, %Actor{} = moderator, :participant) do
+    accept(participation, moderator)
+  end
+
+  def update(%Participant{} = participation, %Actor{} = moderator, :rejected) do
+    reject(participation, moderator)
+  end
+
+  defp accept(
+         %Participant{} = participation,
+         %Actor{} = moderator
+       ) do
+    with {:ok, activity, %Participant{role: :participant} = participation} <-
+           ActivityPub.accept(
+             :join,
+             participation,
+             true,
+             %{"actor" => moderator.url}
+           ),
+         :ok <- Participation.send_emails_to_local_user(participation) do
+      {:ok, activity, participation}
+    end
+  end
+
+  defp reject(
+         %Participant{} = participation,
+         %Actor{} = moderator
+       ) do
+    with {:ok, activity, %Participant{role: :rejected} = participation} <-
+           ActivityPub.reject(
+             :join,
+             participation,
+             %{"actor" => moderator.url}
+           ),
+         :ok <- Participation.send_emails_to_local_user(participation) do
+      {:ok, activity, participation}
+    end
+  end
+end