#!/usr/bin/env node
import { createHash } from "node:crypto";
import { spawnSync } from "node:child_process";
import {
  cp,
  lstat,
  mkdir,
  mkdtemp,
  readFile,
  readdir,
  rm,
  writeFile,
} from "node:fs/promises";
import { tmpdir } from "node:os";
import { basename, dirname, join, relative, 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 artifactDir = resolve(
  process.env.NODEDC_DEPLOY_ARTIFACT_DIR
    || resolve(scriptDir, "../deploy-artifacts"),
);
const runtimeCache = resolve(
  process.env.NODEDC_DEVICE_EDGE_VPS_RUNTIME_DIR || "/tmp",
);

const [phase, patchId, ...extra] = process.argv.slice(2);
if (
  extra.length
  || !["foundation", "backhaul", "relay", "core-channel"].includes(phase)
  || !/^[A-Za-z0-9._-]{1,96}$/.test(patchId || "")
) {
  throw new Error(
    "usage: build-device-edge-vps-artifact.mjs <foundation|backhaul|relay|core-channel> <patch-id>",
  );
}

const supersededTransportPhases = new Set(["backhaul", "relay"]);
if (
  supersededTransportPhases.has(phase)
  && process.env.NODEDC_ALLOW_SUPERSEDED_TRANSPORT !== "test-only"
) {
  throw new Error("vps_initiated_transport_frozen:ADR-0001");
}

const nodeArchive = "node-v22.23.2-linux-x64.tar.xz";
const tailscaleArchive = "tailscale_1.102.2_amd64.tgz";
const runtimeDigests = new Map([
  [nodeArchive, "d60acfe00a2932254bb0ad20e01b0d74397a0875595de719654b214f4b03f307"],
  [tailscaleArchive, "ad2cde12f8de95f7b93a1e0401e652291c603d42b9d60a33fb1741eb38ab04d8"],
]);

const entriesByPhase = {
  foundation: [
    "vps/config/00-nodedc-b2-vps.conf",
    "vps/config/nftables-foundation.conf",
    "vps/systemd/nodedc-b2-tailscaled.service",
    "deployment/device-edge-vps-foundation-v1.json",
    `vendor/${nodeArchive}`,
    `vendor/${tailscaleArchive}`,
  ],
  backhaul: [
    "vps/config/backhaul_ssh_config",
    "vps/systemd/nodedc-b2-backhaul.service",
    "deployment/device-edge-vps-backhaul-v1.json",
  ],
  relay: [
    "vps/config/nftables-relay.conf",
    "vps/systemd/nodedc-b2-relay.service",
    "services/device-edge-relay/src",
    "deployment/device-edge-vps-relay-v1.json",
  ],
  "core-channel": [
    "packages/device-protocol-contract/package.json",
    "packages/device-protocol-contract/src",
    "packages/device-edge-channel-contract/package.json",
    "packages/device-edge-channel-contract/src",
    "services/device-edge-channel/package.json",
    "services/device-edge-channel/src",
    "vps/config/nftables-core-channel.conf",
    "vps/systemd/nodedc-device-edge-channel.service",
    "deployment/device-edge-vps-core-channel-v1.json",
  ],
};
const entries = entriesByPhase[phase];
const ignoredBasenames = new Set([".DS_Store", ".git", "node_modules"]);
const stage = await mkdtemp(join(tmpdir(), `nodedc-device-edge-vps-${phase}-`));
const payload = join(stage, "payload");
const target = join(
  artifactDir,
  `nodedc-device-edge-vps-${patchId}.tgz`,
);

await assertBoundary();

try {
  await mkdir(payload, { recursive: true });
  for (const entry of entries) {
    if (entry.startsWith("vendor/")) {
      const name = basename(entry);
      const source = resolve(runtimeCache, name);
      const actual = createHash("sha256").update(await readFile(source)).digest("hex");
      if (actual !== runtimeDigests.get(name)) {
        throw new Error(`runtime_digest_mismatch:${name}:${actual}`);
      }
      await mkdir(dirname(join(payload, entry)), { recursive: true });
      await cp(source, join(payload, entry), { force: true });
      continue;
    }
    await copySafe(resolve(sourceRoot, entry), join(payload, entry));
  }

  await writeFile(
    join(stage, "manifest.env"),
    `id=${patchId}\ncomponent=device-edge-vps\ntype=app-overlay\n`,
    "utf8",
  );
  await writeFile(join(stage, "files.txt"), `${entries.join("\n")}\n`, "utf8");
  await mkdir(artifactDir, { recursive: true });

  const tar = spawnSync(
    "python3",
    ["-c", canonicalTarScript(), target, stage],
    { encoding: "utf8", maxBuffer: 256 * 1024 * 1024 },
  );
  if (tar.status !== 0) {
    throw new Error(`tar_failed:${tar.stderr || tar.stdout}`);
  }

  const bytes = await readFile(target);
  const digest = createHash("sha256").update(bytes).digest("hex");
  console.log(JSON.stringify({
    ok: true,
    patchId,
    phase,
    artifact: target,
    sha256: digest,
    size: bytes.length,
    component: "device-edge-vps",
    entries,
    publicIngress: phase === "relay"
      ? "tcp/9921"
      : phase === "core-channel"
        ? "tcp/8443-mtls-only"
        : "disabled",
    commandTransport: "disabled",
    gelios: "untouched",
  }, null, 2));
} finally {
  await rm(stage, { recursive: true, force: true });
}

async function assertBoundary() {
  const descriptorPath = resolve(
    sourceRoot,
    `deployment/device-edge-vps-${phase}-v1.json`,
  );
  const descriptor = JSON.parse(await readFile(descriptorPath, "utf8"));
  if (
    descriptor.component !== "device-edge-vps"
    || descriptor.runtimeHost !== "koffyvngij"
    || descriptor.commandTransport !== "disabled"
    || descriptor.gelios !== "untouched"
    || !String(descriptor.rollback || "").length
  ) {
    throw new Error(`descriptor_boundary_mismatch:${phase}`);
  }

  const selectedText = await Promise.all(
    entries
      .filter((entry) => !entry.startsWith("vendor/") && !entry.endsWith("/src"))
      .map((entry) => readFile(resolve(sourceRoot, entry), "utf8")),
  );
  const combined = selectedText.join("\n");
  for (const forbidden of [
    "PRIVATE KEY",
    "AuthKey",
    "TS_AUTHKEY",
    "PasswordAuthentication yes",
    "commandTransport\": \"enabled",
    "device.dc.ru",
  ]) {
    if (combined.includes(forbidden)) {
      throw new Error(`vps_boundary_violation:${forbidden}`);
    }
  }

  if (phase === "foundation") {
    for (const required of [
      "PermitRootLogin prohibit-password",
      "PasswordAuthentication no",
      "AllowTcpForwarding no",
      "policy drop",
      "tcp dport 22",
      "--tun=userspace-networking",
      "--socks5-server=127.0.0.1:1055",
    ]) {
      if (!combined.includes(required)) {
        throw new Error(`foundation_boundary_missing:${required}`);
      }
    }
    if (combined.includes("tcp dport 9921")) {
      throw new Error("foundation_must_not_open_9921");
    }
  }
  if (phase === "backhaul") {
    for (const required of [
      "\"runtimeUser\": \"nodedc-backhaul\"",
      "User=nodedc-backhaul",
      "HostName 100.109.216.21",
      "Port 2222",
      "StrictHostKeyChecking yes",
      "LocalForward 127.0.0.1:19921 127.0.0.1:9921",
      "ProxyCommand /usr/bin/nc -X 5 -x 127.0.0.1:1055",
      "MemoryMax=64M",
    ]) {
      if (!combined.includes(required)) {
        throw new Error(`backhaul_boundary_missing:${required}`);
      }
    }
  }
  if (phase === "relay") {
    for (const required of [
      "\"runtimeUser\": \"nodedc-relay\"",
      "User=nodedc-relay",
      "tcp dport 9921",
      "DEVICE_EDGE_RELAY_UPSTREAM_HOST=127.0.0.1",
      "DEVICE_EDGE_RELAY_UPSTREAM_PORT=19921",
      "DEVICE_EDGE_RELAY_SOURCE_POLICY=public-ipv4-only",
      "MemoryMax=192M",
    ]) {
      if (!combined.includes(required)) {
        throw new Error(`relay_boundary_missing:${required}`);
      }
    }
  }
  if (phase === "core-channel") {
    for (const required of [
      "\"runtimeUser\": \"nodedc-channel\"",
      "\"trackerIngress\": \"disabled\"",
      "User=nodedc-channel",
      "node --jitless",
      "tcp dport 8443",
      "MemoryMax=128M",
      "MemorySwapMax=0",
      "CPUQuota=50%",
      "TasksMax=64",
      "LimitNOFILE=1024",
    ]) {
      if (!combined.includes(required)) {
        throw new Error(`core_channel_boundary_missing:${required}`);
      }
    }
    for (const forbidden of [
      "tcp dport 9921",
      "LocalForward",
      "tailscale-userspace",
      "DEVICE_EDGE_RELAY_UPSTREAM",
    ]) {
      if (combined.includes(forbidden)) {
        throw new Error(`core_channel_boundary_violation:${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");
}

async function copySafe(source, destination) {
  const sourceStat = await lstat(source);
  if (sourceStat.isSymbolicLink()) {
    throw new Error(`source_symlink_rejected:${relative(sourceRoot, source)}`);
  }
  if (sourceStat.isFile()) {
    await mkdir(dirname(destination), { recursive: true });
    await cp(source, destination, { force: true, verbatimSymlinks: true });
    return;
  }
  if (!sourceStat.isDirectory()) {
    throw new Error(`source_type_rejected:${source}`);
  }
  await mkdir(destination, { recursive: true });
  for (const entry of await readdir(source, { withFileTypes: true })) {
    if (ignoredBasenames.has(entry.name) || entry.name.startsWith(".env")) {
      continue;
    }
    const childSource = join(source, entry.name);
    const childDestination = join(destination, entry.name);
    if (entry.isSymbolicLink()) {
      throw new Error(`source_symlink_rejected:${relative(sourceRoot, childSource)}`);
    }
    await copySafe(childSource, childDestination);
  }
}