module.exports = {
    eleventyComputed: {
        // TODO: handle titles as slugs instead of filenames
        permalink: (data) => {
            // get the file path stem ie "/en/blog/2025/2025-10-18-my-post"
            let stem = data.page.filePathStem;

            // strip the leading /en/ prefix
            if (stem.startsWith("/en/")) {
                stem = stem.replace(/^\/en/, "");
            }

            // for blog posts under /blog/[year]/[year-month-day]-blogpost
            // extract the year and the blog post slug (remove date prefix)
            const blogPostMatch = stem.match(/^\/blog\/(\d{4})\/\d{4}-\d{2}-\d{2}-(.+)$/);
            if (blogPostMatch) {
                const [, year, slug] = blogPostMatch;
                return `/blog/${year}/${slug}/index.html`; // ie /blog/2025/my-post/index.html
            }

            // fallback for index or other pages under /blog
            if (stem.endsWith("/index")) {
                return `${stem}.html`; // ie /blog/index.html
            }

            // default for non-index, non-blog-post pages
            return `${stem}/index.html`;
        }
    }
};