Rename 'kohana' to 'system' to conform to the Kohana filesystem layout. I'm comfortable with us not clearly drawing the distinction about the fact that it's Kohana.

system/libraries/Controller.php

@@ -0,0 +1,78 @@
+<?php defined('SYSPATH') OR die('No direct access allowed.');
+/**
+ * Kohana Controller class. The controller class must be extended to work
+ * properly, so this class is defined as abstract.
+ *
+ * $Id: Controller.php 3979 2009-02-13 16:46:12Z zombor $
+ *
+ * @package    Core
+ * @author     Kohana Team
+ * @copyright  (c) 2007-2008 Kohana Team
+ * @license    http://kohanaphp.com/license.html
+ */
+abstract class Controller_Core {
+
+	// Allow all controllers to run in production by default
+	const ALLOW_PRODUCTION = TRUE;
+
+	/**
+	 * Loads URI, and Input into this controller.
+	 *
+	 * @return  void
+	 */
+	public function __construct()
+	{
+		if (Kohana::$instance == NULL)
+		{
+			// Set the instance to the first controller loaded
+			Kohana::$instance = $this;
+		}
+
+		// URI should always be available
+		$this->uri = URI::instance();
+
+		// Input should always be available
+		$this->input = Input::instance();
+	}
+
+	/**
+	 * Handles methods that do not exist.
+	 *
+	 * @param   string  method name
+	 * @param   array   arguments
+	 * @return  void
+	 */
+	public function __call($method, $args)
+	{
+		// Default to showing a 404 page
+		Event::run('system.404');
+	}
+
+	/**
+	 * Includes a View within the controller scope.
+	 *
+	 * @param   string  view filename
+	 * @param   array   array of view variables
+	 * @return  string
+	 */
+	public function _kohana_load_view($kohana_view_filename, $kohana_input_data)
+	{
+		if ($kohana_view_filename == '')
+			return;
+
+		// Buffering on
+		ob_start();
+
+		// Import the view variables to local namespace
+		extract($kohana_input_data, EXTR_SKIP);
+
+		// Views are straight HTML pages with embedded PHP, so importing them
+		// this way insures that $this can be accessed as if the user was in
+		// the controller, which gives the easiest access to libraries in views
+		include $kohana_view_filename;
+
+		// Fetch the output and close the buffer
+		return ob_get_clean();
+	}
+
+} // End Controller Class