#!/usr/bin/env node
import { createHash } from "node:crypto";
import { spawnSync } from "node:child_process";
import {
  cp,
  lstat,
  mkdir,
  mkdtemp,
  readFile,
  rm,
  writeFile,
} from "node:fs/promises";
import { tmpdir } from "node:os";
import { dirname, join, resolve } from "node:path";
import { fileURLToPath } from "node:url";

const scriptDir = dirname(fileURLToPath(import.meta.url));
const platformRoot = resolve(scriptDir, "../..");
const sourceRoot = resolve(platformRoot, "device-plane");
const descriptorRelative =
  "deployment/device-plane-backhaul-vps-enrollment-v1.json";
const artifactDir = resolve(
  process.env.NODEDC_DEPLOY_ARTIFACT_DIR
    || resolve(scriptDir, "../deploy-artifacts"),
);
const [
  patchId = "device-plane-backhaul-vps-enrollment-20260806-001",
  ...extra
] = process.argv.slice(2);

if (extra.length || !/^[A-Za-z0-9._-]{1,96}$/.test(patchId)) {
  throw new Error(
    "usage: build-device-plane-backhaul-vps-enrollment-artifact.mjs [patch-id]",
  );
}

if (process.env.NODEDC_ALLOW_SUPERSEDED_TRANSPORT !== "test-only") {
  throw new Error("vps_initiated_transport_frozen:ADR-0001");
}

const files = [descriptorRelative];
const stage = await mkdtemp(
  join(tmpdir(), "nodedc-device-plane-vps-enrollment-"),
);
const payload = join(stage, "payload");
const target = join(
  artifactDir,
  `nodedc-device-plane-${patchId}.tgz`,
);

await assertDescriptor();

try {
  const source = resolve(sourceRoot, descriptorRelative);
  const sourceStat = await lstat(source);
  if (!sourceStat.isFile() || sourceStat.isSymbolicLink()) {
    throw new Error("device_plane_vps_enrollment_descriptor_unsafe");
  }
  await mkdir(dirname(join(payload, descriptorRelative)), {
    recursive: true,
  });
  await cp(source, join(payload, descriptorRelative), {
    force: true,
    verbatimSymlinks: true,
  });
  await writeFile(
    join(stage, "manifest.env"),
    `id=${patchId}\ncomponent=device-plane\ntype=app-overlay\n`,
    "utf8",
  );
  await writeFile(join(stage, "files.txt"), `${files.join("\n")}\n`, "utf8");
  await mkdir(artifactDir, { recursive: true });

  const tar = spawnSync(
    "python3",
    ["-c", canonicalTarScript(), target, stage],
    { encoding: "utf8", maxBuffer: 32 * 1024 * 1024 },
  );
  if (tar.status !== 0) {
    throw new Error(`tar_failed:${tar.stderr || tar.stdout}`);
  }

  const bytes = await readFile(target);
  const sha256 = createHash("sha256").update(bytes).digest("hex");
  console.log(JSON.stringify({
    ok: true,
    patchId,
    artifact: target,
    sha256,
    component: "device-plane",
    transition: "rotate-backhaul-client-mini-to-vps",
    entries: files,
    build: [],
    services: ["device-backhaul-target"],
    preservedRuntime: [
      "device-control-core",
      "device-gateway",
      "device-postgres",
      "nodedc-device-plane-postgres-data",
      "Tailscale Serve",
      "Gelios",
    ],
    publicIngress: "disabled",
    commandTransport: "disabled",
    runtimeKeyMaterial: "external-enrollment-only",
    rollback: "restore-previous-authorized-key-and-recreate-target",
  }, null, 2));
} finally {
  await rm(stage, { recursive: true, force: true });
}

async function assertDescriptor() {
  const descriptor = JSON.parse(await readFile(
    resolve(sourceRoot, descriptorRelative),
    "utf8",
  ));
  if (
    descriptor.schemaVersion
      !== "nodedc.device-plane.backhaul-vps-enrollment.v1"
    || descriptor.mode !== "rotate-backhaul-client-mini-to-vps"
    || descriptor.predecessorPatchId
      !== "device-plane-backhaul-target-tailnet-serve-20260804-002"
    || descriptor.predecessorArtifactSha256
      !== "219408705dd4d80a962ed00eeb53a69df0b9ab6458443734d5c9cd1d1f795eba"
    || descriptor.nextKeyFingerprint
      !== "SHA256:HHTiDYiCRxSiKjBLCip6JMSzGfLGrDz5g8SIkosJcVw"
    || descriptor.commandTransport !== "disabled"
    || descriptor.gelios !== "untouched"
    || descriptor.edgePublicIngress !== "disabled"
  ) {
    throw new Error("device_plane_vps_enrollment_descriptor_mismatch");
  }
  const text = JSON.stringify(descriptor);
  for (const forbidden of [
    "PRIVATE KEY",
    "authorized_keys",
    "TS_AUTHKEY",
    "password",
  ]) {
    if (text.includes(forbidden)) {
      throw new Error(`device_plane_vps_enrollment_boundary:${forbidden}`);
    }
  }
}

function canonicalTarScript() {
  return [
    "import gzip,io,pathlib,sys,tarfile",
    "root=pathlib.Path(sys.argv[2])",
    "with open(sys.argv[1],'wb') as out:",
    " with gzip.GzipFile(filename='',mode='wb',fileobj=out,compresslevel=9,mtime=0) as gz:",
    "  with tarfile.open(fileobj=gz,mode='w',format=tarfile.PAX_FORMAT) as tar:",
    "   for top in ('manifest.env','files.txt','payload'):",
    "    p=root/top; paths=[p]+(sorted(p.rglob('*')) if p.is_dir() else [])",
    "    for x in paths:",
    "     info=tar.gettarinfo(str(x),arcname=x.relative_to(root).as_posix())",
    "     info.uid=info.gid=0; info.uname=info.gname='root'; info.mtime=0; info.mode=0o755 if info.isdir() else 0o644",
    "     with (open(x,'rb') if info.isfile() else io.BytesIO()) as src: tar.addfile(info,src if info.isfile() else None)",
  ].join("\n");
}