private function build(string $type)
    {
        if (!in_array($type, ['public', 'local'])) {
            throw new \InvalidArgumentException('type accepts public or local');
        }
        if (!$this->called) {
            $url = $type === 'public' ? $this->config->env['public'] : $this->config->env['local'];
            $url = rtrim($url, '/');
            Util::clearDirectory($this->config->path('cache'));
            $articles        = ArticleGenerator::getArticles($this->config->path('article'), $url);
            $paths = $this->config->paths;
            $articles->each(function ($article) use ($paths) {
                $article->createCache("{$paths['cache']}/article");
            });
            $this->generator = new SiteGenerator($this->config, $articles);
            $this->called    = true;
        }
        Util::clearDirectory($this->config->path($type), true);
        $this->generator->generate($type);
    }