import { readFile, writeFile, mkdir, copyFile } from 'node:fs/promises'
import { dirname, join } from 'node:path'
import { fileURLToPath, pathToFileURL } from 'node:url'

const __dirname = dirname(fileURLToPath(import.meta.url))
const repoRoot = join(__dirname, '../..')
const kernelBin = join(repoRoot, 'kernel/bin')
const seederKernelBin = join(repoRoot, 'packages/bare-os-seeder/kernel/bin')
const kernelMan = join(repoRoot, 'kernel/share/man/man.json')
const seederMan = join(
  repoRoot,
  'packages/bare-os-seeder/kernel/share/man/man.json'
)
const runtimePath = join(
  repoRoot,
  'packages/bare-os-coreutils/lib/runtime.js'
)
const coreutilsCommands = join(
  repoRoot,
  'packages/bare-os-coreutils/lib/commands.mjs'
)

export async function build() {
  const runtime = await readFile(runtimePath, 'utf8')
  const body = await readFile(join(__dirname, 'src/sshd.js'), 'utf8')
  const out = runtime + '\n' + body
  await mkdir(kernelBin, { recursive: true })
  await mkdir(seederKernelBin, { recursive: true })
  await writeFile(join(kernelBin, 'sshd'), out)
  await writeFile(join(seederKernelBin, 'sshd'), out)
  await writeFile(join(kernelBin, 'bare-sshd'), out)
  await writeFile(join(seederKernelBin, 'bare-sshd'), out)

  const etcSsh = join(repoRoot, 'kernel/etc/ssh')
  const seederEtc = join(repoRoot, 'packages/bare-os-seeder/kernel/etc/ssh')
  await mkdir(etcSsh, { recursive: true })
  await mkdir(seederEtc, { recursive: true })
  const cfgSrc = join(__dirname, 'etc/ssh/sshd_config')
  await copyFile(cfgSrc, join(etcSsh, 'sshd_config'))
  await copyFile(cfgSrc, join(seederEtc, 'sshd_config'))

  const { COREUTILS_COMMANDS } = await import(
    pathToFileURL(coreutilsCommands).href
  )
  const manRaw = await readFile(kernelMan, 'utf8')
  const db = JSON.parse(manRaw)
  const pages = Array.isArray(db.pages) ? [...db.pages] : []
  for (const name of ['sshd', 'sshd_config']) {
    const add = JSON.parse(
      await readFile(join(__dirname, 'man/pages', `${name}.json`), 'utf8')
    )
    const i = pages.findIndex((p) => p && p.name === name)
    if (i >= 0) pages[i] = add
    else pages.push(add)
  }
  db.pages = pages
  db.generatedAt = new Date().toISOString()
  const manOut = JSON.stringify(db, null, 2) + '\n'
  await mkdir(dirname(kernelMan), { recursive: true })
  await mkdir(dirname(seederMan), { recursive: true })
  await writeFile(kernelMan, manOut)
  await writeFile(seederMan, manOut)

  const posixPath = join(repoRoot, 'kernel/etc/bare-os/posix_utilities.json')
  const seederPosix = join(
    repoRoot,
    'packages/bare-os-seeder/kernel/etc/bare-os/posix_utilities.json'
  )
  let posix = {}
  try {
    posix = JSON.parse(await readFile(posixPath, 'utf8'))
  } catch {
    posix = { schema: 2, commandIndex: [], utilities: {} }
  }
  const idx = Array.isArray(posix.commandIndex) ? [...posix.commandIndex] : []
  const have = new Set(idx.map((r) => r.name))
  for (const name of COREUTILS_COMMANDS) {
    if (!have.has(name)) {
      idx.push({ name, tier: 'tier1_bin' })
      have.add(name)
    }
  }
  if (!have.has('bare-sshd')) {
    idx.push({ name: 'bare-sshd', tier: 'tier1_bin' })
  }
  idx.sort((a, b) => a.name.localeCompare(b.name))
  posix.commandIndex = idx
  await writeFile(posixPath, JSON.stringify(posix, null, 2) + '\n')
  await writeFile(seederPosix, JSON.stringify(posix, null, 2) + '\n')
}

if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href) {
  await build()
}