import fs from 'fs'
import path from 'path'
import matter from 'gray-matter'

const CONTENT_DIR = path.join(process.cwd(), 'content')
const KNIEPUNKT_DIR = path.join(CONTENT_DIR, 'kniepunkt')
const POSTS_DIR = path.join(CONTENT_DIR, 'posts')

function getFiles(dir) {
  return fs.readdirSync(dir).map(f => path.join(dir, f)).filter(f => f.endsWith('.md'))
}

const allPosts = getFiles(POSTS_DIR)
const allKniepunkte = getFiles(KNIEPUNKT_DIR)

// 1. Clean up Kniepunkt Residues in posts/
allPosts.forEach(post => {
  const filename = path.basename(post)
  if (filename.match(/^0[1-9][0-9]/)) {
    const issueMatch = filename.match(/^0([1-9][0-9])/)
    if (issueMatch) {
      const issueNum = issueMatch[1]
      const matchingKniepunkt = allKniepunkte.find(k => path.basename(k).includes(`0${issueNum}`) || path.basename(k).includes(issueNum))
      if (matchingKniepunkt) {
        console.log(`🗑️ Deleting residue in posts/: ${filename}`)
        fs.unlinkSync(post)
      } else {
        // move to kniepunkt
        const newPath = path.join(KNIEPUNKT_DIR, filename)
        fs.renameSync(post, newPath)
        console.log(`➡️ Moved residue to kniepunkt/: ${filename}`)
        allKniepunkte.push(newPath)
      }
    }
  }
})

// 2. Merge intro posts in kniepunkt/
const introPosts = allKniepunkte.filter(k => path.basename(k).match(/^202[0-9]-/))
introPosts.forEach(intro => {
  const introData = matter(fs.readFileSync(intro, 'utf8'))
  const titleMatch = introData.data.title.match(/kniepunkt\s*0?(\d+)/i) || path.basename(intro).match(/kniepunkt-0?(\d+)/i)
  
  if (titleMatch) {
    const issueNum = titleMatch[1]
    const article = allKniepunkte.find(k => k !== intro && (path.basename(k).includes(`0${issueNum}`) || path.basename(k).includes(`-${issueNum}-`)) && !path.basename(k).match(/^202[0-9]-/))
    
    if (article) {
      const articleData = matter(fs.readFileSync(article, 'utf8'))
      const mergedContent = introData.content.trim() + '\n\n---\n\n' + articleData.content.trim()
      articleData.data.date = introData.data.date
      fs.writeFileSync(article, matter.stringify(mergedContent, articleData.data))
      fs.unlinkSync(intro)
      console.log(`✅ Merged Intro ${path.basename(intro)} -> ${path.basename(article)}`)
    } else {
      console.log(`⚠️ Could not find article for intro: ${path.basename(intro)} (Issue ${issueNum})`)
    }
  }
})