// ── Shared trusted-device establishment ────────────────────────────────────
//
// One place that mints + persists a trusted device, enforces the per-user cap
// (no silent pruning), and audit-logs it. Reused by every path that can create a
// trust: web /auth/login/totp, mobile /auth/mobile/login, and the authenticated
// self-service POST /auth/me/trusted-devices (the "revoke one, then retry" path
// after a cap-reached prompt).
//
// The caller decides how the returned trust token reaches the client: the web
// paths set the httpOnly rg_trust cookie (setTrustCookie); native paths return the
// token in the JSON body for EncryptedSharedPreferences. This helper never touches
// res, so it stays surface-agnostic.

const trustedDevices = require('../../../model/trustedDevices/trustedDevices.model')
const activity = require('../../../model/activity/activity.model')
const sessionService = require('../../../auth/session.service')

const log = require('../../../utils/logger')('trusted-device')

// Attempt to trust the current device for `user`. Returns:
//   { ok: true, trustToken }                     — trusted; caller delivers the token
//   { ok: false, capReached: true, devices }     — at the cap; caller prompts to revoke
// `platform` is 'web' | 'mobile'; `deviceName` is the optional friendly label.
async function establishTrust(req, user, { platform = 'web', deviceName = null } = {}) {
  if (await sessionService.trustDeviceCapReached(user.id)) {
    const devices = await trustedDevices.listActiveForUser(user.id)
    log.info('trust refused — device cap reached', { userId: user.id, platform })
    return { ok: false, capReached: true, devices }
  }
  const meta = sessionService.sessionMeta(req)
  const out = sessionService.mintTrustToken(meta)
  await trustedDevices.store({
    userId: user.id,
    tokenHash: out.trustHash,
    platform,
    deviceName,
    deviceHash: out.deviceHash,
    userAgent: out.userAgent,
    expiresAt: out.expiresAt,
  })
  await activity.log({ req, userId: user.id, action: 'account.trusted_device.add', detail: { platform } })
  log.info('device trusted', { userId: user.id, platform })
  return { ok: true, trustToken: out.trustToken }
}

module.exports = { establishTrust }
