#!/usr/bin/env node
// Pair this machine with a dsh-remote master WITHOUT a running local DSH: exchange a
// one-time pairing code for a device key and write the slave link state.
//   node deploy/pair.mjs --master http://192.168.0.111:3080 --code ABCD-... --name my-mac [--state <file>]
// The state file defaults to $DSH_HOME/profiles/web/dsh-remote/state.json. Restart DSH after.
import fs from 'node:fs'
import os from 'node:os'
import path from 'node:path'

const args = process.argv.slice(2)
const opt = (k, d) => { const i = args.indexOf(`--${k}`); return i >= 0 ? args[i + 1] : d }
const master = String(opt('master', '')).replace(/\/+$/, '')
const code = opt('code', '')
const name = opt('name', os.hostname())
const home = process.env.DSH_HOME || path.join(os.homedir(), '.dsh')
const stateFile = opt('state', path.join(home, 'profiles', opt('profile', 'web'), 'dsh-remote', 'state.json'))
if (!/^https?:\/\//.test(master) || !code) {
  console.error('usage: pair.mjs --master <http(s)://…> --code <pairing code> [--name <device name>]')
  process.exit(2)
}

const slug = (s) => String(s || '').toLowerCase().replace(/[^a-z0-9-]+/g, '-').replace(/^-+|-+$/g, '').slice(0, 40) || 'device'
let state = {}
try { state = JSON.parse(fs.readFileSync(stateFile, 'utf8')) } catch { state = {} }
state.self ||= { id: slug(name), name, createdAt: Date.now() }
state.self.name = name

const r = await fetch(`${master}/dsh-remote/enroll`, {
  method: 'POST',
  headers: { 'content-type': 'application/json' },
  body: JSON.stringify({ code: code.trim().toUpperCase(), id: state.self.id, name, platform: `${process.platform}-${process.arch}` }),
  redirect: 'manual',
})
let j = {}
try { j = await r.json() } catch { j = {} }
if (r.status >= 300 && r.status < 400) {
  console.error(`pairing failed: ${master} redirected (${r.headers.get('location')?.slice(0, 80)}…). A login proxy (e.g. Authentik) is in front of /dsh-remote/enroll; use the LAN URL or exempt that path.`)
  process.exit(1)
}
if (!r.ok) { console.error(`pairing failed: ${j.error || `HTTP ${r.status}`}`); process.exit(1) }

state.master = { url: master, deviceId: j.deviceId, key: j.key, master: j.master, pairedAt: Date.now() }
state.self.id = j.deviceId
fs.mkdirSync(path.dirname(stateFile), { recursive: true, mode: 0o700 })
const tmp = `${stateFile}.${process.pid}.tmp`
fs.writeFileSync(tmp, JSON.stringify(state, null, 2), { mode: 0o600 })
fs.renameSync(tmp, stateFile)
console.log(`paired as "${j.deviceId}" with master ${j.master?.name || master}`)