import fs from "node:fs";
import { spawnSync } from "node:child_process";

const ADVISORY_URL = "https://github.com/advisories/GHSA-vfj7-8cjw-p6xm";
const EXPECTED_VULNERABILITIES = [
  "@next/eslint-plugin-next",
  "braces",
  "eslint-config-next",
  "fast-glob",
  "micromatch",
].sort();

const EXPECTED_VERSIONS = new Map([
  ["next", "16.3.8"],
  ["eslint-config-next", "16.3.8"],
  ["@next/eslint-plugin-next", "16.3.8"],
  ["fast-glob", "3.3.1"],
  ["micromatch", "4.0.8"],
  ["braces", "3.0.3"],
]);

function fail(message) {
  console.error(`Dependency audit exception rejected: ${message}`);
  process.exit(1);
}

function packageVersion(lock, name) {
  const entry = lock.packages?.[`node_modules/${name}`];
  return typeof entry?.version === "string" ? entry.version : null;
}

const npmCommand = process.platform === "win32" ? "npm.cmd" : "npm";
const audit = spawnSync(
  npmCommand,
  ["audit", "--audit-level=moderate", "--json"],
  {
    encoding: "utf8",
    maxBuffer: 8 * 1024 * 1024,
    shell: process.platform === "win32",
    windowsHide: true,
  },
);

if (audit.error) {
  fail(`npm audit could not start: ${audit.error.name}`);
}
if (audit.status !== 0 && audit.status !== 1) {
  fail(`npm audit returned unexpected exit code ${audit.status}`);
}

let report;
try {
  report = JSON.parse(audit.stdout);
} catch {
  fail("npm audit returned invalid JSON");
}

if (report.auditReportVersion !== 2 || typeof report.vulnerabilities !== "object") {
  fail("npm audit report schema changed");
}

const names = Object.keys(report.vulnerabilities).sort();
if (audit.status === 0) {
  if (names.length !== 0) {
    fail("npm audit exited cleanly but still reported vulnerabilities");
  }
  console.log("Full dependency audit is clean.");
  process.exit(0);
}

if (JSON.stringify(names) !== JSON.stringify(EXPECTED_VULNERABILITIES)) {
  fail(`unexpected vulnerability set: ${names.join(", ")}`);
}

const counts = report.metadata?.vulnerabilities;
if (
  !counts ||
  counts.info !== 0 ||
  counts.low !== 0 ||
  counts.moderate !== 0 ||
  counts.high !== 5 ||
  counts.critical !== 0 ||
  counts.total !== 5
) {
  fail("vulnerability counts differ from the reviewed exception");
}

const lock = JSON.parse(fs.readFileSync(new URL("../package-lock.json", import.meta.url), "utf8"));
for (const [name, expected] of EXPECTED_VERSIONS) {
  const actual = packageVersion(lock, name);
  if (actual !== expected) {
    fail(`${name} changed from reviewed version ${expected} to ${actual ?? "missing"}`);
  }
}

const vulnerabilities = report.vulnerabilities;
for (const name of EXPECTED_VULNERABILITIES) {
  const item = vulnerabilities[name];
  if (!item || item.severity !== "high" || !Array.isArray(item.via)) {
    fail(`${name} no longer matches the reviewed high-severity audit shape`);
  }
}

const directNames = EXPECTED_VULNERABILITIES.filter(
  (name) => vulnerabilities[name].isDirect === true,
);
if (JSON.stringify(directNames) !== JSON.stringify(["eslint-config-next"])) {
  fail(`unexpected direct dependency findings: ${directNames.join(", ") || "none"}`);
}

const expectedChain = new Map([
  ["eslint-config-next", "@next/eslint-plugin-next"],
  ["@next/eslint-plugin-next", "fast-glob"],
  ["fast-glob", "micromatch"],
  ["micromatch", "braces"],
]);
for (const [name, expectedVia] of expectedChain) {
  if (!vulnerabilities[name].via.includes(expectedVia)) {
    fail(`${name} no longer resolves through ${expectedVia}`);
  }
}

const bracesAdvisories = vulnerabilities.braces.via.filter(
  (entry) => entry && typeof entry === "object",
);
if (bracesAdvisories.length !== 1) {
  fail("braces advisory count changed");
}
const advisory = bracesAdvisories[0];
if (
  String(advisory.source) !== "1240992" ||
  advisory.name !== "braces" ||
  advisory.severity !== "high" ||
  advisory.range !== "<=3.0.3" ||
  advisory.url !== ADVISORY_URL
) {
  fail("braces advisory identity or affected range changed");
}

const fix = vulnerabilities["eslint-config-next"].fixAvailable;
if (
  !fix ||
  typeof fix !== "object" ||
  fix.name !== "eslint-config-next" ||
  fix.version !== "14.2.35" ||
  fix.isSemVerMajor !== true
) {
  fail("npm now reports a different remediation; review and remove/update this exception");
}

console.log(
  "Accepted reviewed dev-tooling exception only: GHSA-vfj7-8cjw-p6xm via eslint-config-next -> @next/eslint-plugin-next -> fast-glob -> micromatch -> braces@3.0.3.",
);
console.log("Production dependencies remain covered by the separate strict production audit.");