Implement module system and DDate module

modules/DDate.rb

@@ -0,0 +1,19 @@
+require 'xmpp4r/message'
+
+require_relative '../module_base'
+
+module Lain
+  module Modules
+    class DDate < Base
+      def on_message(muc, message)
+        return unless message.type == :groupchat
+        return unless /!ddate\b/ =~ message.body
+
+        p = IO.popen("ddate")
+        while (line = p.gets)
+          muc.send(Jabber::Message.new(message.to, line.chomp))
+        end
+      end
+    end
+  end
+end