route.ts

import type { Node, Root } from 'fumadocs-core/page-tree';
import { rewriteCookbookUrl } from '@/lib/geistdocs/cookbook-source';
import { source } from '@/lib/geistdocs/source';

export const revalidate = false;
export const dynamic = 'force-static';

export async function GET(
  _req: Request,
  { params }: RouteContext<'/[lang]/sitemap.md'>
) {
  const { lang } = await params;
  let mdText = '';

  function traverseTree(node: Node | Root, depth = 0) {
    const indent = '  '.repeat(depth);

    if ('type' in node) {
      if (node.type === 'page') {
        mdText += `${indent}- [${node.name}](${rewriteCookbookUrl(node.url)})\n`;
      } else if (node.type === 'folder') {
        if (node.index) {
          mdText += `${indent}- [${node.name}](${rewriteCookbookUrl(node.index.url)})\n`;
        } else {
          mdText += `${indent}- ${node.name}\n`;
        }
        if (node.children.length > 0) {
          for (const child of node.children) {
            traverseTree(child, depth + 1);
          }
        }
      }
    } else if (node.children.length > 0) {
      for (const child of node.children) {
        traverseTree(child, depth);
      }
    }
  }

  const tree = source.getPageTree(lang);
  traverseTree(tree, 0);

  return new Response(mdText, {
    headers: {
      'Content-Type': 'text/markdown',
    },
  });
}