Introduce group basic federation, event new page and notifications

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/web/email/group.ex

@@ -0,0 +1,47 @@
+defmodule Mobilizon.Web.Email.Group do
+  @moduledoc """
+  Handles emails sent about participation.
+  """
+  use Bamboo.Phoenix, view: Mobilizon.Web.EmailView
+
+  import Bamboo.Phoenix
+  import Mobilizon.Web.Gettext
+
+  alias Mobilizon.{Actors, Users}
+  alias Mobilizon.Actors.{Actor, Member}
+  alias Mobilizon.Users.User
+  alias Mobilizon.Web.{Email, Gettext}
+
+  @doc """
+  Send emails to local user
+  """
+  def send_invite_to_user(
+        %Member{actor: %Actor{user_id: user_id}, parent: %Actor{} = group, role: :invited} =
+          member,
+        locale \\ "en"
+      ) do
+    with %User{email: email} <- Users.get_user!(user_id) do
+      Gettext.put_locale(locale)
+      %Actor{name: invited_by_name} = inviter = Actors.get_actor(member.invited_by_id)
+
+      subject =
+        gettext(
+          "You have been invited by %{inviter} to join group %{group}",
+          inviter: invited_by_name,
+          group: group.name
+        )
+
+      Email.base_email(to: email, subject: subject)
+      |> assign(:locale, locale)
+      |> assign(:inviter, inviter)
+      |> assign(:group, group)
+      |> assign(:subject, subject)
+      |> render(:group_invite)
+      |> Email.Mailer.deliver_later()
+
+      :ok
+    end
+  end
+
+  # TODO : def send_confirmation_to_inviter()
+end