#!/usr/bin/env node
/**
 * Generates src/lib/last-updated-routes.js by scanning src/pages for .mdx files
 * and reading the last commit date for each from git. Used by Layout.jsx to
 * render an "Updated <date>" line in the right rail.
 *
 * Skips src/pages/ipa/resources/ — those are auto-generated from the OpenAPI
 * spec, so their git date reflects generator runs, not real content edits.
 *
 * Run automatically with dev and build.
 */

import fs from 'fs'
import path from 'path'
import { fileURLToPath } from 'url'
import { getGitLastModified } from './git-dates.mjs'

const __dirname = path.dirname(fileURLToPath(import.meta.url))
const ROOT = path.join(__dirname, '..')
const PAGES_DIR = path.join(ROOT, 'src/pages')
const OUT_PATH = path.join(ROOT, 'src/lib/last-updated-routes.mjs')
const SKIP_PREFIX = 'ipa/resources'

function findMdxRoutes(dir, basePath = '') {
  const entries = fs.readdirSync(dir, { withFileTypes: true })
  const results = []
  for (const e of entries) {
    const rel = basePath ? `${basePath}/${e.name}` : e.name
    if (e.isDirectory()) {
      if (rel === SKIP_PREFIX || rel.startsWith(`${SKIP_PREFIX}/`)) continue
      results.push(...findMdxRoutes(path.join(dir, e.name), rel))
    } else if (e.name.endsWith('.mdx')) {
      const filePath = path.join(dir, e.name)
      const route =
        e.name === 'index.mdx'
          ? '/' + basePath
          : '/' + rel.replace(/\.mdx$/, '')
      results.push({ route, filePath })
    }
  }
  return results
}

const entries = findMdxRoutes(PAGES_DIR)
  .filter((r) => r.route !== '/' && r.route !== '')
  .sort((a, b) => a.route.localeCompare(b.route))

const map = {}
for (const { route, filePath } of entries) {
  const date = getGitLastModified(filePath)
  if (date) map[route] = date
}

const content = `// Auto-generated by scripts/generate-last-updated.mjs – do not edit
/** Last commit date (YYYY-MM-DD) keyed by Next.js router.pathname. */
export const LAST_UPDATED_BY_ROUTE = ${JSON.stringify(map, null, 2)};
`

fs.mkdirSync(path.dirname(OUT_PATH), { recursive: true })
fs.writeFileSync(OUT_PATH, content, 'utf8')
console.log('Generated', OUT_PATH, 'with', Object.keys(map).length, 'dated routes')