// 构建前将 posts/ 目录处理为静态数据
// 1. 复制图片等静态文件到 public/posts/
// 2. 生成 posts-data.json 供前端直接导入

import { cpSync, existsSync, rmSync, readdirSync, statSync, readFileSync, mkdirSync, writeFileSync } from 'fs'
import { join, dirname, relative } from 'path'
import { fileURLToPath } from 'url'

const __dirname = dirname(fileURLToPath(import.meta.url))
const root = join(__dirname, '..')
const src = join(root, 'posts')
const dst = join(root, 'public', 'posts')

// 1. 复制静态文件到 public/posts/
if (existsSync(dst)) {
  rmSync(dst, { recursive: true, force: true })
}

cpSync(src, dst, {
  recursive: true,
  filter: (srcPath) => !srcPath.endsWith('.md')
})

console.log('已同步 posts 静态文件到 public/posts/')

// 2. 扫描 posts/ 生成数据清单
function scanDir(dir) {
  const entries = readdirSync(dir)
  const result = { dirs: [], files: [] }

  for (const name of entries) {
    if (name.startsWith('.')) continue
    const full = join(dir, name)
    const st = statSync(full)

    if (st.isDirectory()) {
      const children = scanDir(full)
      // 跳过空目录
      if (children.dirs.length === 0 && children.files.length === 0) continue
      result.dirs.push({ name, children })
    } else if (name.endsWith('.md')) {
      const relPath = relative(src, full).replace(/\\/g, '/').replace(/\.md$/, '')
      const content = readFileSync(full, 'utf-8')
      result.files.push({ name: name.replace('.md', ''), path: relPath, content })
    }
  }

  // 排序：文件夹在前，文件在后，各自字母排序
  result.dirs.sort((a, b) => a.name.localeCompare(b.name))
  result.files.sort((a, b) => a.name.localeCompare(b.name))

  return result
}

function buildTree(scanResult) {
  const items = []

  for (const dir of scanResult.dirs) {
    items.push({ type: 'category', name: dir.name, children: buildTree(dir.children) })
  }

  for (const file of scanResult.files) {
    items.push({ type: 'post', name: file.name, path: file.path })
  }

  return items
}

function buildContentMap(scanResult, map = {}) {
  for (const file of scanResult.files) {
    map[file.path] = file.content
  }
  for (const dir of scanResult.dirs) {
    buildContentMap(dir.children, map)
  }
  return map
}

function getAllPaths(scanResult, paths = []) {
  for (const file of scanResult.files) {
    paths.push(file.path)
  }
  for (const dir of scanResult.dirs) {
    getAllPaths(dir.children, paths)
  }
  return paths
}

const scanResult = scanDir(src)
const data = {
  tree: buildTree(scanResult),
  contentMap: buildContentMap(scanResult),
  paths: getAllPaths(scanResult)
}

const outDir = join(root, 'src', 'generated')
mkdirSync(outDir, { recursive: true })
writeFileSync(join(outDir, 'posts-data.json'), JSON.stringify(data))

console.log(`已生成 posts-data.json (${data.paths.length} 篇文章)`)