Introduce group basic federation, event new page and notifications

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

lib/mobilizon/conversations/conversation.ex

@@ -0,0 +1,53 @@
+defmodule Mobilizon.Conversations.Conversation.TitleSlug do
+  @moduledoc """
+  Module to generate the slug for conversations
+  """
+  use EctoAutoslugField.Slug, from: :title, to: :slug
+end
+
+defmodule Mobilizon.Conversations.Conversation do
+  @moduledoc """
+  Represents a conversation
+  """
+
+  use Ecto.Schema
+
+  import Ecto.Changeset
+
+  alias Mobilizon.Actors.Actor
+  alias Mobilizon.Conversations.Comment
+  alias Mobilizon.Conversations.Conversation.TitleSlug
+
+  @type t :: %__MODULE__{
+          creator: Actor.t(),
+          actor: Actor.t(),
+          title: String.t(),
+          slug: String.t(),
+          last_comment: Comment.t(),
+          comments: list(Comment.t())
+        }
+
+  @required_attrs [:actor_id, :creator_id, :title, :last_comment_id]
+  @optional_attrs []
+  @attrs @required_attrs ++ @optional_attrs
+
+  schema "conversations" do
+    field(:title, :string)
+    field(:slug, TitleSlug.Type)
+    belongs_to(:creator, Actor)
+    belongs_to(:actor, Actor)
+    belongs_to(:last_comment, Comment)
+    has_many(:comments, Comment, foreign_key: :conversation_id)
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @doc false
+  @spec changeset(t, map) :: Ecto.Changeset.t()
+  def changeset(%__MODULE__{} = conversation, attrs) do
+    conversation
+    |> cast(attrs, @attrs)
+    |> validate_required(@required_attrs)
+    |> TitleSlug.maybe_generate_slug()
+  end
+end