app.php

<?php

// main app class. This is created in the main index.php file and everything is loaded from here.
class App
{
  /** @var null The controller */
  private $urlController = null;

  /** @var null The method (of the above controller), often also named "action" */
  private $urlAction = null;

  /** @var null Parameter one */
  private $urlParameter1 = null;
  private $urlParameter2 = null;
  private $urlParameter3 = null;
  private $urlParameter4 = null;
  private $urlParameter5 = null;
  private $urlParameter6 = null;

  // construct the App class
  public function __construct()
  {
    // start session
    Session::start();

    // create array with URL parts in $url
    if(isset($_GET['url'])) {
      // split URL
      $url = rtrim($_GET['url'], '/');
      $url = filter_var($url, FILTER_SANITIZE_URL);
      $url = explode('/', $url);

      // Put URL parts into according properties
      // note the first one is always /root because the mod-rewrite sends us there
      $this->urlController = (isset($url[0]) ? strtolower($url[0]) : null);
      $this->urlAction = (isset($url[1]) ? strtolower($url[1]) : null);
      $this->urlParameter1 = (isset($url[2]) ? strtolower($url[2]) : null);
      $this->urlParameter2 = (isset($url[3]) ? strtolower($url[3]) : null);
      $this->urlParameter3 = (isset($url[4]) ? strtolower($url[4]) : null);
      $this->urlParameter4 = (isset($url[5]) ? strtolower($url[5]) : null);
      $this->urlParameter5 = (isset($url[6]) ? strtolower($url[6]) : null);
      $this->urlParameter6 = (isset($url[7]) ? strtolower($url[7]) : null);
    }

    // check for controller: does such a controller exist ?
    // Also make sure we are not trying to load / (index) because this will try and load the
    // plain controller.php and shit will die
    $fileName = CONTROLLER_DIR . $this->urlController . '-controller.php';
    if(file_exists($fileName) && $this->urlController != '') {
      // get the controller file
      require_once($fileName);

      // create controller name by converting underscored words to camelcase
      $controllerName = str_replace(
        ' ', '', ucwords(str_replace('-', ' ', $this->urlController))
      ) . 'Controller';

      $this->urlController = new $controllerName();
      $action = str_replace('-', '_', $this->urlAction);

      // check for method: does such a method exist in the controller ?
      if(method_exists($this->urlController, $action)) {
        // call the method and pass the arguments to it
        if(isset($this->urlParameter1)) {
          if(isset($this->urlParameter2)) {
            if(isset($this->urlParameter3)) {
              if(isset($this->urlParameter4)) {
                if(isset($this->urlParameter5)) {
                  if(isset($this->urlParameter6)) {
                    // will translate to something like:
                    // $this->home->method($param1, $param2, $param3, $param4, $param5, $param6);
                    $this->urlController->{$action}(
                        $this->urlParameter1,
                        $this->urlParameter2,
                        $this->urlParameter3,
                        $this->urlParameter4,
                        $this->urlParameter5,
                        $this->urlParameter6
                    );
                  } else {
                    // will translate to something like: 
                    // $this->home->method($param1, $param2, $param3, $param4, $param5);
                    $this->urlController->{$action}(
                      $this->urlParameter1,
                      $this->urlParameter2,
                      $this->urlParameter3,
                      $this->urlParameter4,
                      $this->urlParameter5
                    );
                  }
                } else {
                  // will translate to something like:
                  // $this->home->method($param1, $param2, $param3, $param3);
                  $this->urlController->{$action}(
                    $this->urlParameter1,
                    $this->urlParameter2,
                    $this->urlParameter3,
                    $this->urlParameter4
                  );
                }
              } else {
                // will translate to something like:
                // $this->home->method($param_1, $param_2, $param_3);
                $this->urlController->{$action}(
                  $this->urlParameter1,
                  $this->urlParameter2,
                  $this->urlParameter3
                );
              }
            } else {
              // will translate to something like: $this->home->method($param_1, $param_2);
              $this->urlController->{$action}($this->urlParameter1, $this->urlParameter2);
            }
          } else {
            // will translate to something like: $this->home->method($param_1);
            $this->urlController->{$action}($this->urlParameter1);
          }
        } else {
          // if no parameters given, just call the method without parameters, like:
          // $this->home->method();
          $this->urlController->{$action}();
        }
      } else {
        // cause error if method not found or load index if blank
        if($action != '') {
          // make sure it exists, render it
          header('HTTP/1.0 404 Not Found');
          // get the controller file
          require_once(CONTROLLER_DIR . 'root-controller.php');
          $rootController = new RootController();
          debug('<h2>Missing controller method</h2><p>The method <strong>'
            . $action
            . '()</strong> does not exist. Create method inside '
            . $controllerName
            . ' and make sure it has a view file.</p>');
          $rootController->status404();
        } else {
          $this->urlController->index();
        }
      }
    } else {
      if(!isset($url)) {
        // invalid URL, so simply show root/index
        require_once(CONTROLLER_DIR . 'root-controller.php');
        $rootController = new RootController();
        $rootController->index();
      } else {
        header('HTTP/1.0 404 Not Found');
        // invalid URL, so simply show root/index
        require_once(CONTROLLER_DIR . 'root-controller.php');
        $rootController = new RootController();
        $rootController->status404();
      }
    }

    // end session
    Session::close();
  }
}