Game event and event handler

lib/battleship.ex

@@ -13,7 +13,8 @@ defmodule Battleship do
       supervisor(Battleship.Endpoint, []),
       # Here you could define other workers and supervisors as children
       # worker(Battleship.Worker, [arg1, arg2, arg3]),
-      supervisor(Battleship.Game.Supervisor, [])
+      supervisor(Battleship.Game.Supervisor, []),
+      worker(Battleship.Game.Event, [])
     ]
 
     # See http://elixir-lang.org/docs/stable/elixir/Supervisor.html

lib/battleship/game/event.ex

@@ -0,0 +1,17 @@
+defmodule Battleship.Game.Event do
+  def start_link do
+    {:ok, manager} = GenEvent.start_link(name: __MODULE__)
+
+    handlers = [
+      Battleship.Game.EventHandler
+    ]
+
+    Enum.each(handlers, &GenEvent.add_handler(manager, &1, []))
+
+    {:ok, manager}
+  end
+
+  def game_created, do: GenEvent.notify(__MODULE__, :game_created)
+  def player_joined, do: GenEvent.notify(__MODULE__, :player_joined)
+  def game_over, do: GenEvent.notify(__MODULE__, :game_over)
+end

lib/battleship/game/event_handler.ex

@@ -0,0 +1,16 @@
+defmodule Battleship.Game.EventHandler do
+  use GenEvent
+  alias Battleship.LobbyChannel
+
+  def handle_event(:game_created, state), do: broadcast_update(state)
+  def handle_event(:player_joined, state), do: broadcast_update(state)
+  def handle_event(:game_over, state), do: broadcast_update(state)
+
+  def handle_event(_, state), do: {:ok, state}
+
+  defp broadcast_update(state) do
+    LobbyChannel.broadcast_current_games
+
+    {:ok, state}
+  end
+end