// 从 content/articles/*.md 读取文章列表和详情
import fs from 'node:fs'
import path from 'node:path'
import matter from 'gray-matter'
import { marked } from 'marked'

const DIR = path.join(process.cwd(), 'content', 'articles')

function readAll() {
  if (!fs.existsSync(DIR)) return []
  return fs.readdirSync(DIR)
    .filter((f) => f.endsWith('.md'))
    .map((fileName) => {
      const fullPath = path.join(DIR, fileName)
      const raw = fs.readFileSync(fullPath, 'utf8')
      const { data, content } = matter(raw)
      const slug = fileName.replace(/\.md$/, '')
      const dateMatch = fileName.match(/^(\d{4}-\d{2}-\d{2})-/)
      const date = dateMatch ? dateMatch[1] : ''
      return {
        slug,
        date,
        title: data.title || slug.replace(/^\d{4}-\d{2}-\d{2}-/, ''),
        excerpt: content.replace(/\s+/g, ' ').trim().slice(0, 150) + (content.length > 150 ? '...' : ''),
      }
    })
    .sort((a, b) => (a.date < b.date ? 1 : -1))
}

export function listArticles() {
  return readAll().map(({ slug, title, date, excerpt }) => ({ slug, title, date, excerpt }))
}

export function getArticle(slug) {
  // 防止路径穿越
  if (slug.includes('/') || slug.includes('\\') || slug.includes('..')) return null
  const fullPath = path.join(DIR, slug + '.md')
  if (!fs.existsSync(fullPath)) return null
  const raw = fs.readFileSync(fullPath, 'utf8')
  const { data, content } = matter(raw)
  const dateMatch = slug.match(/^(\d{4}-\d{2}-\d{2})-/)
  const date = dateMatch ? dateMatch[1] : ''
  return {
    slug,
    date,
    title: data.title || slug.replace(/^\d{4}-\d{2}-\d{2}-/, ''),
    contentHtml: marked.parse(content),
  }
}