import regionsData from '../../data/regions.json'

export default defineEventHandler((event) => {
  const config = useRuntimeConfig()
  const baseUrl = config.public.siteDomain || 'https://aeseo.shop'
  const list = regionsData.list as Array<{ sido: string, sigungu: string, dong: string }>
  const uniqueDongs = Array.from(new Set(list.map(r => r.dong).filter(Boolean)))
  const today = new Date().toISOString().split('T')[0]

  const subjects = ['수학', '영어', '국어', '과학', '사회']
  const grades = ['초등학생', '중학생', '고등학생']
  const subjectImages: Record<string, string> = {
    '수학': `${baseUrl}/img/math-tutoring.png`,
    '영어': `${baseUrl}/img/english-tutoring.png`,
    '국어': `${baseUrl}/img/korean-tutoring.png`,
    '과학': `${baseUrl}/img/science-tutoring.png`,
    '사회': `${baseUrl}/img/social-studies-tutoring.png`
  }

  let xml = `<?xml version="1.0" encoding="UTF-8"?>\n`
  xml += `<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:image="http://www.google.com/schemas/sitemap-image/1.1">\n`

  // 메인
  xml += `  <url>\n    <loc>${baseUrl}/</loc>\n    <lastmod>${today}</lastmod>\n    <changefreq>daily</changefreq>\n    <priority>1.0</priority>\n`
  xml += `    <image:image><image:loc>${baseUrl}/img/og-main.png</image:loc></image:image>\n`
  xml += `    <image:image><image:loc>${baseUrl}/img/math-tutoring.png</image:loc></image:image>\n`
  xml += `    <image:image><image:loc>${baseUrl}/img/english-tutoring.png</image:loc></image:image>\n`
  xml += `    <image:image><image:loc>${baseUrl}/img/korean-tutoring.png</image:loc></image:image>\n`
  xml += `    <image:image><image:loc>${baseUrl}/img/science-tutoring.png</image:loc></image:image>\n`
  xml += `    <image:image><image:loc>${baseUrl}/img/social-studies-tutoring.png</image:loc></image:image>\n`
  xml += `  </url>\n`

  // 중복 제거된 동별 주요 과목 및 학년 URL 생성 (슬래시 라우터 구조 통일)
  uniqueDongs.forEach(dong => {
    // 1. 동 대표
    xml += `  <url>\n    <loc>${baseUrl}/${encodeURIComponent(dong)}</loc>\n    <lastmod>${today}</lastmod>\n    <changefreq>weekly</changefreq>\n    <priority>0.8</priority>\n    <image:image><image:loc>${baseUrl}/img/math-tutoring.png</image:loc></image:image>\n  </url>\n`
    
    // 2. 동/학년/과목 조합
    grades.forEach(g => {
      subjects.forEach(sub => {
        const imgLoc = subjectImages[sub] || `${baseUrl}/img/math-tutoring.png`
        xml += `  <url>\n    <loc>${baseUrl}/${encodeURIComponent(dong)}/${encodeURIComponent(g)}/${encodeURIComponent(sub)}</loc>\n    <lastmod>${today}</lastmod>\n    <changefreq>weekly</changefreq>\n    <priority>0.7</priority>\n    <image:image><image:loc>${imgLoc}</image:loc></image:image>\n  </url>\n`
      })
    })
  })

  xml += `</urlset>`

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