#!/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 sourceRoot = resolve(scriptDir, "..");
const artifactRoot = resolve(
  process.env.NODEDC_DEPLOY_ARTIFACT_DIR || resolve(sourceRoot, "deploy-artifacts"),
);
const artifactId = "ops-agents-reboot-resilience-20260809-001";
const component = "ops-agents";
const files = [
  "docker-compose.synology.yml",
  "src/db/wait-for-database.test.ts",
  "src/db/wait-for-database.ts",
  "src/scripts/migrate.ts",
];
const predecessors = {
  "docker-compose.synology.yml": "e78d37368c3d255f257086773ba908e44aae2e475661b80ee17f98c3d55d178f",
  "src/scripts/migrate.ts": "8396a42deded31f1fe2381f772838a33b05bfd389075ebd34a5f546593f08769",
};
const newPaths = [
  "src/db/wait-for-database.test.ts",
  "src/db/wait-for-database.ts",
];

await mkdir(artifactRoot, { recursive: true });
const artifact = join(artifactRoot, `nodedc-${artifactId}.tgz`);
const predecessorPath = join(artifactRoot, `nodedc-${artifactId}.predecessor.sha256`);
const newPathsPath = join(artifactRoot, `nodedc-${artifactId}.new-paths`);
await Promise.all([artifact, predecessorPath, newPathsPath].map(assertFresh));

const stage = await mkdtemp(join(tmpdir(), "nodedc-ops-agents-reboot-resilience-"));
const payload = join(stage, "payload");

try {
  await mkdir(payload, { recursive: true });
  for (const relativePath of files) {
    validateRelativePath(relativePath);
    const source = join(sourceRoot, relativePath);
    const info = await lstat(source);
    if (!info.isFile() || info.isSymbolicLink()) {
      throw new Error(`invalid_source_file:${relativePath}`);
    }
    await mkdir(dirname(join(payload, relativePath)), { recursive: true });
    await cp(source, join(payload, relativePath), { force: false });
  }

  await writeFile(
    join(stage, "manifest.env"),
    `id=${artifactId}\ncomponent=${component}\ntype=app-overlay\n`,
    "utf8",
  );
  await writeFile(join(stage, "files.txt"), `${files.join("\n")}\n`, "utf8");
  run("python3", ["-c", canonicalTarScript(), artifact, stage]);

  const productionRoot = "/volume1/docker/nodedc-platform/ops-agents";
  await writeFile(
    predecessorPath,
    `${Object.entries(predecessors)
      .map(([relativePath, digest]) => `${digest}  ${productionRoot}/${relativePath}`)
      .join("\n")}\n`,
    "utf8",
  );
  await writeFile(
    newPathsPath,
    `${newPaths.map((relativePath) => `${productionRoot}/${relativePath}`).join("\n")}\n`,
    "utf8",
  );

  const artifactBytes = await readFile(artifact);
  console.log(JSON.stringify({
    ok: true,
    artifactId,
    component,
    artifact,
    artifactSha256: sha256(artifactBytes),
    files,
    predecessors,
    newPaths,
    expectedService: "agent-gateway",
    expectedHealthcheck: "http://172.22.0.222:18190/readyz",
    runnerChanged: false,
    databaseVolumeSelected: false,
  }, null, 2));
} finally {
  await rm(stage, { recursive: true, force: true });
}

async function assertFresh(path) {
  try {
    await lstat(path);
  } catch (error) {
    if (error?.code === "ENOENT") return;
    throw error;
  }
  throw new Error(`output_already_exists:${path}`);
}

function validateRelativePath(value) {
  if (
    typeof value !== "string"
    || !value
    || value.startsWith("/")
    || value.split("/").some((part) => !part || part === "." || part === "..")
  ) {
    throw new Error(`unsafe_relative_path:${value}`);
  }
}

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");
}

function run(command, args) {
  const result = spawnSync(command, args, {
    encoding: "utf8",
    maxBuffer: 128 * 1024 * 1024,
    stdio: ["ignore", "pipe", "pipe"],
  });
  if (result.status !== 0) {
    throw new Error(`${command}_failed:${result.stderr || result.stdout}`);
  }
}

function sha256(bytes) {
  return createHash("sha256").update(bytes).digest("hex");
}