/**
   * Parser Controller
   *
   **/
  class Parser extends Controller {

    /**
     * Parser Constructor
     *
     * @return void
     **/
    public function Parser() {
      parent::Controller();
      $this->load->library('highlighter');
    }

    /**
     * Default Parser Page
     *
     * @return void
     **/
    public function index() {
      // We're going to test it by having it render itself.
      $code = file_get_contents(
        'system/application/controllers/parser.php'
      );

      $this->load->view('highlight_test', array(
        'code' => $this->do_highlight($code, 'php')
      ));
    }

    /**
     * Do the syntax highlighting
     *
     * @return string The highlighted source code
     **/
    private function do_highlight($code, $lang) {
      $highlighted_code = $this->highlighter->syntax(
        $code,
        $lang
      );
      // Run extras that Geshi missed
      $highlighted_code = $this->do_highlight_extras($highlighted_code, $lang);
      return $highlighted_code;
    }

    /**
     * Since Geshi sucks a fat cock, I have to put these here. I couldn't
     * get Geshi to do this for me. This should be redone in Geshi if possible.
     *
     * @return string The highlighted source code with highlighted extras
     **/
    private function do_highlight_extras($code, $lang) {
      // Define the extra function to run based on the selected language
      switch($lang) {
        case 'php':
          $extras = array(
            'class_names',
            'extends_class_names',
            'scope_resolution_operators',
            'dash_arrows'
          );
        break;
        default:
          // We don't have any to take care of, so just exit out
          return $code;
      }
      // Loop through the extra functions, and if they exist, run em.
      foreach($extras as $extra) {
        $method = 'highlight_' . $lang . '_' . $extra;
        $code = $this->$method($code);
      }
      return $code;
    }

    /**
     * PHP Source Extra
     * Find all of the class names and highlight them.
     *
     * @return string The highlighted source code including this extra
     **/
    private function highlight_php_class_names($code) {
      $result = preg_replace(
        '/\>class\<\/span\> ([A-Za-z0-9_]+)/',
        '>class</span> <span class="re3">$1</span>',
        $code
      );
      return $result;
    }

    /**
     * PHP Source Extra
     * Find all of the class names that extend another class and highlight them.
     *
     * @return string The highlighted source code including this extra
     **/
    private function highlight_php_extends_class_names($code) {
      $result = preg_replace(
        '/\>extends\<\/span\> ([A-Za-z0-9_]+)/',
        '>extends</span> <span class="re3 it">$1</span>',
        $code
      );
      return $result;
    }

    /**
     * PHP Source Extra
     * Find all ::'s and highlight them.
     *
     * @return string The highlighted source code including this extra
     **/
    private function highlight_php_scope_resolution_operators($code) {
      $result = str_replace(
        '::',
        '<span class="kw2">::</span>',
        $code
      );
      return $result;
    }

    /**
     * PHP Source Extra
     * Find all of the ->'s and highlight them.
     *
     * @return string The highlighted source code including this extra
     **/
    private function highlight_php_dash_arrows($code) {
      $result = str_replace(
        '-&gt;',
        '<span class="kw2">-&gt;</span>',
        $code
      );
      return $result;
    }

  }