/**
 * Regenerates the simple cache.
 *
 * see elgg_view_register_simplecache
 *
 */
function elgg_view_regenerate_simplecache() {
    global $CONFIG;

    // todo elgg_view() checks if the page set is done (isset($CONFIG->pagesetupdone)) and
    // triggers an event if it's not. Calling elgg_view() here breaks submenus
    // (at least) because the page setup hook is called before any
    // contexts can be correctly set (since this is called before page_handler()).
    // To avoid this, lie about $CONFIG->pagehandlerdone to force
    // the trigger correctly when the first view is actually being output.
    $CONFIG->pagesetupdone = TRUE;

    if (isset($CONFIG->views->simplecache)) {
        if (!file_exists($CONFIG->dataroot . 'views_simplecache')) {
            mkdir($CONFIG->dataroot . 'views_simplecache');
        }

        if (!empty($CONFIG->views->simplecache) && is_array($CONFIG->views->simplecache)) {
            foreach($CONFIG->views->simplecache as $view) {
                $viewcontents = elgg_view($view);
                if ($view == 'css') {
                    $viewcontents = compress_css($viewcontents);
                }
                $viewname = md5(elgg_get_viewtype() . $view);
                if ($handle = fopen($CONFIG->dataroot . 'views_simplecache/' . $viewname, 'w')) {
                    fwrite($handle, $viewcontents);
                    fclose($handle);
                }
            }
        }

        datalist_set('simplecache_lastupdate', 0);
    }

    unset($CONFIG->pagesetupdone);
}

/* compress css content - see http://websitetips.com/articles/optimization/css/crunch/ */
function compress_css($buffer) {
    /* remove comments */
        $buffer = preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!', '', $buffer);
    /* remove tabs, spaces, new lines, etc. */        
        $buffer = str_replace(array("\r\n", "\r", "\n", "\t", '  ', '    ', '    '), '', $buffer);
    /* remove unnecessary spaces */        
        $buffer = str_replace('{ ', '{', $buffer);
        $buffer = str_replace(' }', '}', $buffer);
        $buffer = str_replace('; ', ';', $buffer);
        $buffer = str_replace(', ', ',', $buffer);
        $buffer = str_replace(' {', '{', $buffer);
        $buffer = str_replace('} ', '}', $buffer);
        $buffer = str_replace(': ', ':', $buffer);
        $buffer = str_replace(' ,', ',', $buffer);
        $buffer = str_replace(' ;', ';', $buffer);

    return $buffer;
}