import { execFileSync, spawnSync } from "node:child_process";
import { mkdirSync, readFileSync } from "node:fs";
import { dirname, resolve } from "node:path";
import { fileURLToPath } from "node:url";
import { build } from "esbuild";

const projectRoot = fileURLToPath(new URL("../", import.meta.url));
const packageJson = JSON.parse(
  readFileSync(resolve(projectRoot, "package.json"), "utf8"),
);

function getRevision() {
  const suppliedRevision = process.env.DOCKDECK_BUILD_REVISION?.trim();
  if (suppliedRevision) return normalizeRevision(suppliedRevision);

  try {
    return normalizeRevision(
      execFileSync("git", ["rev-parse", "--verify", "HEAD"], {
        cwd: projectRoot,
        encoding: "utf8",
        stdio: ["ignore", "pipe", "ignore"],
      }).trim(),
    );
  } catch {
    return "development";
  }
}

function normalizeRevision(revision) {
  if (revision === "development") return revision;

  const normalizedRevision = revision.toLowerCase();
  if (!/^(?:[a-f0-9]{40}|[a-f0-9]{64})$/.test(normalizedRevision)) {
    throw new Error(
      "DOCKDECK_BUILD_REVISION must be a complete 40- or 64-character Git revision.",
    );
  }

  return normalizedRevision;
}

function getBuildDate() {
  const buildDate = process.env.DOCKDECK_BUILD_DATE ?? new Date().toISOString();
  const parsedDate = new Date(buildDate);
  const hasMilliseconds = /\.\d{3}Z$/.test(buildDate);
  const canonicalBuildDate = hasMilliseconds
    ? buildDate
    : `${buildDate.slice(0, -1)}.000Z`;
  if (
    !/^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(?:\.\d{3})?Z$/.test(buildDate) ||
    Number.isNaN(parsedDate.getTime()) ||
    parsedDate.toISOString() !== canonicalBuildDate
  ) {
    throw new Error(
      "DOCKDECK_BUILD_DATE must be a canonical UTC ISO timestamp with optional milliseconds.",
    );
  }

  return buildDate;
}

const suppliedVersion = process.env.DOCKDECK_BUILD_VERSION?.trim();
if (suppliedVersion && suppliedVersion !== packageJson.version) {
  throw new Error(
    `DOCKDECK_BUILD_VERSION (${suppliedVersion}) does not match package.json (${packageJson.version}).`,
  );
}

const revision = getRevision();
const buildDate = getBuildDate();
if (revision !== "development" && Date.parse(buildDate) === 0) {
  throw new Error(
    "DOCKDECK_BUILD_DATE must be a real UTC build timestamp when a full Git revision is provided.",
  );
}

const buildInfo = {
  version: packageJson.version,
  revision,
  shortRevision: revision === "development" ? "dev" : revision.slice(0, 12),
  buildDate,
};

function runNodeScript(scriptPath, args = []) {
  const result = spawnSync(
    process.execPath,
    [resolve(projectRoot, scriptPath), ...args],
    { cwd: projectRoot, stdio: "inherit" },
  );
  if (result.error) throw result.error;
  if (result.status !== 0) process.exit(result.status ?? 1);
}

runNodeScript("node_modules/typescript/bin/tsc", ["-b"]);
runNodeScript("node_modules/vite/bin/vite.js", ["build"]);

const serverOutput = resolve(projectRoot, "dist/server/index.js");
mkdirSync(dirname(serverOutput), { recursive: true });
await build({
  entryPoints: [resolve(projectRoot, "src/server/index.ts")],
  bundle: true,
  platform: "node",
  format: "esm",
  packages: "external",
  outfile: serverOutput,
  define: {
    __DOCKDECK_BUILD_INFO__: JSON.stringify(buildInfo),
  },
});