// src/app/sitemap.xml/route.ts
import { NextResponse } from 'next/server';
import { generateAllSeoUrls, SITEMAP_CHUNK_SIZE } from '@/lib/seo';

export const dynamic = 'force-dynamic';
export const revalidate = 86400; // 24 heures

export async function GET() {
  const allUrls = generateAllSeoUrls();
  const totalChunks = Math.ceil(allUrls.length / SITEMAP_CHUNK_SIZE);
  const now = new Date().toISOString();

  let xml = '<?xml version="1.0" encoding="UTF-8"?>\n';
  xml += '<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">\n';

  // Sitemap statique des pages principales
  xml += '  <sitemap>\n';
  xml += `    <loc>https://www.wisebil.com/sitemap/static.xml</loc>\n`;
  xml += `    <lastmod>${now}</lastmod>\n`;
  xml += '  </sitemap>\n';

  // Sitemaps par tranche programmatique
  for (let i = 0; i < totalChunks; i++) {
    xml += '  <sitemap>\n';
    xml += `    <loc>https://www.wisebil.com/sitemap/${i}.xml</loc>\n`;
    xml += `    <lastmod>${now}</lastmod>\n`;
    xml += '  </sitemap>\n';
  }

  xml += '</sitemapindex>';

  return new NextResponse(xml, {
    status: 200,
    headers: {
      'Content-Type': 'application/xml',
      'Cache-Control': 'public, s-maxage=86400, stale-while-revalidate=43200',
    },
  });
}