source: sourcecode/system/core/Router.php @ 1

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package             CodeIgniter
 * @author              ExpressionEngine Dev Team
 * @copyright   Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license             http://codeigniter.com/user_guide/license.html
 * @link                http://codeigniter.com
 * @since               Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * Router Class
 *
 * Parses URIs and determines routing
 *
 * @package             CodeIgniter
 * @subpackage  Libraries
 * @author              ExpressionEngine Dev Team
 * @category    Libraries
 * @link                http://codeigniter.com/user_guide/general/routing.html
 */
class CI_Router {

        /**
         * Config class
         *
         * @var object
         * @access public
         */
        var $config;
        /**
         * List of routes
         *
         * @var array
         * @access public
         */
        var $routes                     = array();
        /**
         * List of error routes
         *
         * @var array
         * @access public
         */
        var $error_routes       = array();
        /**
         * Current class name
         *
         * @var string
         * @access public
         */
        var $class                      = '';
        /**
         * Current method name
         *
         * @var string
         * @access public
         */
        var $method                     = 'index';
        /**
         * Sub-directory that contains the requested controller class
         *
         * @var string
         * @access public
         */
        var $directory          = '';
        /**
         * Default controller (and method if specific)
         *
         * @var string
         * @access public
         */
        var $default_controller;

        /**
         * Constructor
         *
         * Runs the route mapping function.
         */
        function __construct()
        {
                $this->config =& load_class('Config', 'core');
                $this->uri =& load_class('URI', 'core');
                log_message('debug', "Router Class Initialized");
        }

        // --------------------------------------------------------------------

        /**
         * Set the route mapping
         *
         * This function determines what should be served based on the URI request,
         * as well as any "routes" that have been set in the routing config file.
         *
         * @access      private
         * @return      void
         */
        function _set_routing()
        {
                // Are query strings enabled in the config file?  Normally CI doesn't utilize query strings
                // since URI segments are more search-engine friendly, but they can optionally be used.
                // If this feature is enabled, we will gather the directory/class/method a little differently
                $segments = array();
                if ($this->config->item('enable_query_strings') === TRUE AND isset($_GET[$this->config->item('controller_trigger')]))
                {
                        if (isset($_GET[$this->config->item('directory_trigger')]))
                        {
                                $this->set_directory(trim($this->uri->_filter_uri($_GET[$this->config->item('directory_trigger')])));
                                $segments[] = $this->fetch_directory();
                        }

                        if (isset($_GET[$this->config->item('controller_trigger')]))
                        {
                                $this->set_class(trim($this->uri->_filter_uri($_GET[$this->config->item('controller_trigger')])));
                                $segments[] = $this->fetch_class();
                        }

                        if (isset($_GET[$this->config->item('function_trigger')]))
                        {
                                $this->set_method(trim($this->uri->_filter_uri($_GET[$this->config->item('function_trigger')])));
                                $segments[] = $this->fetch_method();
                        }
                }

                // Load the routes.php file.
                if (defined('ENVIRONMENT') AND is_file(APPPATH.'config/'.ENVIRONMENT.'/routes.php'))
                {
                        include(APPPATH.'config/'.ENVIRONMENT.'/routes.php');
                }
                elseif (is_file(APPPATH.'config/routes.php'))
                {
                        include(APPPATH.'config/routes.php');
                }

                $this->routes = ( ! isset($route) OR ! is_array($route)) ? array() : $route;
                unset($route);

                // Set the default controller so we can display it in the event
                // the URI doesn't correlated to a valid controller.
                $this->default_controller = ( ! isset($this->routes['default_controller']) OR $this->routes['default_controller'] == '') ? FALSE : strtolower($this->routes['default_controller']);

                // Were there any query string segments?  If so, we'll validate them and bail out since we're done.
                if (count($segments) > 0)
                {
                        return $this->_validate_request($segments);
                }

                // Fetch the complete URI string
                $this->uri->_fetch_uri_string();

                // Is there a URI string? If not, the default controller specified in the "routes" file will be shown.
                if ($this->uri->uri_string == '')
                {
                        return $this->_set_default_controller();
                }

                // Do we need to remove the URL suffix?
                $this->uri->_remove_url_suffix();

                // Compile the segments into an array
                $this->uri->_explode_segments();

                // Parse any custom routing that may exist
                $this->_parse_routes();

                // Re-index the segment array so that it starts with 1 rather than 0
                $this->uri->_reindex_segments();
        }

        // --------------------------------------------------------------------

        /**
         * Set the default controller
         *
         * @access      private
         * @return      void
         */
        function _set_default_controller()
        {
                if ($this->default_controller === FALSE)
                {
                        show_error("Unable to determine what should be displayed. A default route has not been specified in the routing file.");
                }
                // Is the method being specified?
                if (strpos($this->default_controller, '/') !== FALSE)
                {
                        $x = explode('/', $this->default_controller);

                        $this->set_class($x[0]);
                        $this->set_method($x[1]);
                        $this->_set_request($x);
                }
                else
                {
                        $this->set_class($this->default_controller);
                        $this->set_method('index');
                        $this->_set_request(array($this->default_controller, 'index'));
                }

                // re-index the routed segments array so it starts with 1 rather than 0
                $this->uri->_reindex_segments();

                log_message('debug', "No URI present. Default controller set.");
        }

        // --------------------------------------------------------------------

        /**
         * Set the Route
         *
         * This function takes an array of URI segments as
         * input, and sets the current class/method
         *
         * @access      private
         * @param       array
         * @param       bool
         * @return      void
         */
        function _set_request($segments = array())
        {
                $segments = $this->_validate_request($segments);

                if (count($segments) == 0)
                {
                        return $this->_set_default_controller();
                }

                $this->set_class($segments[0]);

                if (isset($segments[1]))
                {
                        // A standard method request
                        $this->set_method($segments[1]);
                }
                else
                {
                        // This lets the "routed" segment array identify that the default
                        // index method is being used.
                        $segments[1] = 'index';
                }

                // Update our "routed" segment array to contain the segments.
                // Note: If there is no custom routing, this array will be
                // identical to $this->uri->segments
                $this->uri->rsegments = $segments;
        }

        // --------------------------------------------------------------------

        /**
         * Validates the supplied segments.  Attempts to determine the path to
         * the controller.
         *
         * @access      private
         * @param       array
         * @return      array
         */
        function _validate_request($segments)
        {
                if (count($segments) == 0)
                {
                        return $segments;
                }

                // Does the requested controller exist in the root folder?
                if (file_exists(APPPATH.'controllers/'.$segments[0].'.php'))
                {
                        return $segments;
                }

                // Is the controller in a sub-folder?
                if (is_dir(APPPATH.'controllers/'.$segments[0]))
                {
                        // Set the directory and remove it from the segment array
                        $this->set_directory($segments[0]);
                        $segments = array_slice($segments, 1);

                        if (count($segments) > 0)
                        {
                                // Does the requested controller exist in the sub-folder?
                                if ( ! file_exists(APPPATH.'controllers/'.$this->fetch_directory().$segments[0].'.php'))
                                {
                                        if ( ! empty($this->routes['404_override']))
                                        {
                                                $x = explode('/', $this->routes['404_override']);

                                                $this->set_directory('');
                                                $this->set_class($x[0]);
                                                $this->set_method(isset($x[1]) ? $x[1] : 'index');

                                                return $x;
                                        }
                                        else
                                        {
                                                show_404($this->fetch_directory().$segments[0]);
                                        }
                                }
                        }
                        else
                        {
                                // Is the method being specified in the route?
                                if (strpos($this->default_controller, '/') !== FALSE)
                                {
                                        $x = explode('/', $this->default_controller);

                                        $this->set_class($x[0]);
                                        $this->set_method($x[1]);
                                }
                                else
                                {
                                        $this->set_class($this->default_controller);
                                        $this->set_method('index');
                                }

                                // Does the default controller exist in the sub-folder?
                                if ( ! file_exists(APPPATH.'controllers/'.$this->fetch_directory().$this->default_controller.'.php'))
                                {
                                        $this->directory = '';
                                        return array();
                                }

                        }

                        return $segments;
                }


                // If we've gotten this far it means that the URI does not correlate to a valid
                // controller class.  We will now see if there is an override
                if ( ! empty($this->routes['404_override']))
                {
                        $x = explode('/', $this->routes['404_override']);

                        $this->set_class($x[0]);
                        $this->set_method(isset($x[1]) ? $x[1] : 'index');

                        return $x;
                }


                // Nothing else to do at this point but show a 404
                show_404($segments[0]);
        }

        // --------------------------------------------------------------------

        /**
         *  Parse Routes
         *
         * This function matches any routes that may exist in
         * the config/routes.php file against the URI to
         * determine if the class/method need to be remapped.
         *
         * @access      private
         * @return      void
         */
        function _parse_routes()
        {
                // Turn the segment array into a URI string
                $uri = implode('/', $this->uri->segments);

                // Is there a literal match?  If so we're done
                if (isset($this->routes[$uri]))
                {
                        return $this->_set_request(explode('/', $this->routes[$uri]));
                }

                // Loop through the route array looking for wild-cards
                foreach ($this->routes as $key => $val)
                {
                        // Convert wild-cards to RegEx
                        $key = str_replace(':any', '.+', str_replace(':num', '[0-9]+', $key));

                        // Does the RegEx match?
                        if (preg_match('#^'.$key.'$#', $uri))
                        {
                                // Do we have a back-reference?
                                if (strpos($val, '$') !== FALSE AND strpos($key, '(') !== FALSE)
                                {
                                        $val = preg_replace('#^'.$key.'$#', $val, $uri);
                                }

                                return $this->_set_request(explode('/', $val));
                        }
                }

                // If we got this far it means we didn't encounter a
                // matching route so we'll set the site default route
                $this->_set_request($this->uri->segments);
        }

        // --------------------------------------------------------------------

        /**
         * Set the class name
         *
         * @access      public
         * @param       string
         * @return      void
         */
        function set_class($class)
        {
                $this->class = str_replace(array('/', '.'), '', $class);
        }

        // --------------------------------------------------------------------

        /**
         * Fetch the current class
         *
         * @access      public
         * @return      string
         */
        function fetch_class()
        {
                return $this->class;
        }

        // --------------------------------------------------------------------

        /**
         *  Set the method name
         *
         * @access      public
         * @param       string
         * @return      void
         */
        function set_method($method)
        {
                $this->method = $method;
        }

        // --------------------------------------------------------------------

        /**
         *  Fetch the current method
         *
         * @access      public
         * @return      string
         */
        function fetch_method()
        {
                if ($this->method == $this->fetch_class())
                {
                        return 'index';
                }

                return $this->method;
        }

        // --------------------------------------------------------------------

        /**
         *  Set the directory name
         *
         * @access      public
         * @param       string
         * @return      void
         */
        function set_directory($dir)
        {
                $this->directory = str_replace(array('/', '.'), '', $dir).'/';
        }

        // --------------------------------------------------------------------

        /**
         *  Fetch the sub-directory (if any) that contains the requested controller class
         *
         * @access      public
         * @return      string
         */
        function fetch_directory()
        {
                return $this->directory;
        }

        // --------------------------------------------------------------------

        /**
         *  Set the controller overrides
         *
         * @access      public
         * @param       array
         * @return      null
         */
        function _set_overrides($routing)
        {
                if ( ! is_array($routing))
                {
                        return;
                }

                if (isset($routing['directory']))
                {
                        $this->set_directory($routing['directory']);
                }

                if (isset($routing['controller']) AND $routing['controller'] != '')
                {
                        $this->set_class($routing['controller']);
                }

                if (isset($routing['function']))
                {
                        $routing['function'] = ($routing['function'] == '') ? 'index' : $routing['function'];
                        $this->set_method($routing['function']);
                }
        }


}
// END Router Class

/* End of file Router.php */
/* Location: ./system/core/Router.php */