public function generatePaths(string $root) : array
    {
        $theme = null;
        if (isset($this->env['theme'])) {
            $theme = $this->themes[$this->env['theme']];
        }
        return [
            'cache'     => "{$root}/cache",
            'public'    => "{$root}/public",
            'local'     => "{$root}/local",
            'contents'  => "{$root}/contents",
            'article'   => "{$root}/contents/article",
            'page'      => "{$root}/contents/page",
            'file'      => "{$root}/contents/file",
            'markdown'  => "{$root}/contents/markdown",
            'theme'     => $theme,
        ];
    }