function normalizeBaseUrl(value) {
  const raw = String(value || '').trim()
  if (!raw) return ''
  return raw.replace(/\/+$/, '')
}

function escapeXml(value) {
  return String(value)
    .replace(/&/g, '&')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;')
    .replace(/'/g, '&apos;')
}

function toAbsoluteUrl(baseUrl, path) {
  const normalizedPath = path.startsWith('/') ? path : `/${path}`
  return `${baseUrl}${normalizedPath}`
}

export default defineEventHandler((event) => {
  const runtimeConfig = useRuntimeConfig(event)
  const requestUrl = getRequestURL(event)

  const baseUrl = normalizeBaseUrl(runtimeConfig.public?.baseUrl) || `${requestUrl.protocol}//${requestUrl.host}`
  const today = new Date().toISOString().slice(0, 10)

  const routes = [
    '/',
    '/kontakt',
    '/termine',
    '/mitgliedschaft',
    '/spielplan',
    '/mannschaften',
    '/mannschaften/spielplaene',
    '/mannschaften/herren',
    '/mannschaften/damen',
    '/mannschaften/jugend',
    '/training',
    '/training/trainer',
    '/training/anfaenger',
    '/vereinsmeisterschaften',
    '/spielsysteme',
    '/links',
    '/vorstand',
    '/impressum',
    '/datenschutz',
    '/tt-regeln',
    '/ueber-uns',
    '/geschichte',
    '/satzung',
    '/galerie',
    '/verein/ueber-uns',
    '/verein/geschichte',
    '/verein/satzung',
    '/verein/tt-regeln',
    '/verein/galerie',
    '/newsletter/subscribe',
    '/newsletter/unsubscribe'
  ]

  const uniqueRoutes = [...new Set(routes)]

  const entries = uniqueRoutes.map((route) => {
    const loc = escapeXml(toAbsoluteUrl(baseUrl, route))
    const priority = route === '/' ? '1.0' : '0.7'
    return [
      '  <url>',
      `    <loc>${loc}</loc>`,
      `    <lastmod>${today}</lastmod>`,
      '    <changefreq>weekly</changefreq>',
      `    <priority>${priority}</priority>`,
      '  </url>'
    ].join('\n')
  })

  const xml = [
    '<?xml version="1.0" encoding="UTF-8"?>',
    '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">',
    entries.join('\n'),
    '</urlset>',
    ''
  ].join('\n')

  setHeader(event, 'Content-Type', 'application/xml; charset=utf-8')
  return xml
})