#!/usr/bin/env node

import { createHash } from "node:crypto";
import { spawnSync } from "node:child_process";
import { copyFile, 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 workspaceRoot = resolve(scriptDir, "../../..");
const foundryRoot = resolve(workspaceRoot, "NODEDC_DESIGN_GUIDELINE");
const artifactDir = resolve(
  process.env.NODEDC_DEPLOY_ARTIFACT_DIR || resolve(scriptDir, "../deploy-artifacts"),
);
const [patchId = "module-foundry-map-grid-lod-20260805-001", ...extra] =
  process.argv.slice(2);

if (extra.length || !/^module-foundry-map-grid-lod-\d{8}-\d{3}$/.test(patchId)) {
  throw new Error(
    "usage: build-module-foundry-grid-lod-artifact.mjs "
      + "[module-foundry-map-grid-lod-YYYYMMDD-NNN]",
  );
}

const files = Object.freeze([
  "apps/catalog/src/CesiumMapRenderer.tsx",
  "apps/catalog/src/MapFixturePreview.tsx",
  "apps/catalog/src/mapGridPolicy.d.mts",
  "apps/catalog/src/mapGridPolicy.mjs",
  "package.json",
  "runtime-seed/page-layouts/map.json",
  "scripts/map-grid-lod.test.mjs",
  "server/catalog-server.mjs",
  "server/foundry-mcp.mjs",
]);
const artifact = join(artifactDir, `nodedc-${patchId}.tgz`);
const checksum = `${artifact}.sha256`;
const stage = await mkdtemp(join(tmpdir(), "nodedc-foundry-map-grid-lod-"));

await assertFresh(artifact);
await assertGridLodBoundary();

try {
  for (const relativePath of files) {
    const source = join(foundryRoot, relativePath);
    const info = await lstat(source);
    if (!info.isFile() || info.isSymbolicLink()) {
      throw new Error(`source_file_rejected:${relativePath}`);
    }
    const destination = join(stage, "payload", relativePath);
    await mkdir(dirname(destination), { recursive: true });
    await copyFile(source, destination);
  }
  await writeFile(
    join(stage, "manifest.env"),
    `id=${patchId}\ncomponent=module-foundry\ntype=app-overlay\n`,
    "utf8",
  );
  await writeFile(join(stage, "files.txt"), `${files.join("\n")}\n`, "utf8");
  await mkdir(artifactDir, { recursive: true });
  run("python3", ["-c", canonicalTarScript(), artifact, stage]);
  const sha256 = digest(await readFile(artifact));
  await writeFile(checksum, `${sha256}  ${artifact.split("/").at(-1)}\n`, "utf8");
  console.log(JSON.stringify({
    ok: true,
    patchId,
    artifact,
    checksum,
    sha256,
    services: ["nodedc-module-foundry"],
    transition: "five-band-grid-lod-with-seamless-layer-swap",
    files,
  }, null, 2));
} finally {
  await rm(stage, { recursive: true, force: true });
}

async function assertGridLodBoundary() {
  const policy = await readFile(join(foundryRoot, "apps/catalog/src/mapGridPolicy.mjs"), "utf8");
  const renderer = await readFile(join(foundryRoot, "apps/catalog/src/CesiumMapRenderer.tsx"), "utf8");
  const inspector = await readFile(join(foundryRoot, "apps/catalog/src/MapFixturePreview.tsx"), "utf8");
  const server = await readFile(join(foundryRoot, "server/catalog-server.mjs"), "utf8");
  const tests = await readFile(join(foundryRoot, "scripts/map-grid-lod.test.mjs"), "utf8");

  for (const marker of ["gridLod1MaxHeightKm", "gridLod5StepKm", "GRID_LOD_HYSTERESIS_RATIO"]) {
    if (!policy.includes(marker)) throw new Error(`grid_policy_marker_missing:${marker}`);
  }
  for (const marker of ["class GridLayerController", "corridor:", "gridLineDiameterMeters"]) {
    if (!renderer.includes(marker)) throw new Error(`grid_renderer_marker_missing:${marker}`);
  }
  if (/function rebuildElevatedGrid[\s\S]*?entities\.removeAll\(\)/.test(renderer)) {
    throw new Error("grid_renderer_destructive_layer_swap_detected");
  }
  for (const marker of ["LOD 5: режим", "3D-линии: диаметр", "Гратикула: толщина"]) {
    if (!inspector.includes(marker)) throw new Error(`grid_inspector_marker_missing:${marker}`);
  }
  for (const marker of ["gridLod5Mode", "gridLineDiameterMeters", "gridRebuildOnMoveEnd"]) {
    if (!server.includes(marker)) throw new Error(`grid_server_contract_missing:${marker}`);
  }
  for (const marker of [
    "five grid LODs preserve the close 3D and distant graticule contract",
    "LOD hysteresis holds the previous band around a threshold",
    "renderer swaps double-buffered data sources and never clears the live grid first",
  ]) {
    if (!tests.includes(marker)) throw new Error(`grid_regression_missing:${marker}`);
  }
}

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

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

function run(command, args) {
  const result = spawnSync(command, args, {
    encoding: "utf8",
    maxBuffer: 64 * 1024 * 1024,
  });
  if (result.status !== 0) {
    throw new Error(`${command}_failed:${result.stderr || result.stdout}`);
  }
}