Export an event though ics

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

lib/eventos/export/icalendar.ex

@@ -0,0 +1,19 @@
+defmodule Eventos.Export.ICalendar do
+  @moduledoc """
+  Export an event to iCalendar format
+  """
+
+  alias Eventos.Events.Event
+
+  @spec export_event(%Event{}) :: String
+  def export_event(%Event{} = event) do
+    events = [%ICalendar.Event{
+      summary: event.title,
+      dtstart: event.begins_on,
+      dtend: event.ends_on,
+      description: event.description
+    }]
+    %ICalendar{events: events}
+    |> ICalendar.to_ics()
+  end
+end