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

const root = path.resolve(import.meta.dirname, "../..");
const arg = (name, fallback = null) => {
  const index = process.argv.indexOf(name);
  return index >= 0 ? process.argv[index + 1] : fallback;
};
const wasmSplit = path.join(root, ".emsdk/upstream/bin/wasm-split");
const input = arg("--input", "web/app/public/vendor/blender/web_engine.wasm");
const outputDir = arg("--output-dir", "web/app/public/vendor/blender/modules");
const manifestPath = arg("--manifest", "web/app/public/wasm-module-manifest.json");
const splitFunctions = arg("--split-funcs", "web_engine_get_live_handles");
if (!fs.existsSync(path.join(root, input))) throw new Error(`WASM input is missing: ${input}`);
if (!fs.existsSync(wasmSplit)) throw new Error(`wasm-split is missing: ${wasmSplit}`);
const destination = path.join(root, outputDir);
fs.mkdirSync(destination, { recursive: true });
const stem = path.basename(input, ".wasm");
const primary = path.join(destination, `${stem}.primary.wasm`);
const secondary = path.join(destination, `${stem}.secondary.wasm`);
const result = spawnSync(wasmSplit, [
  "--split", "--all-features", "--split-funcs", splitFunctions,
  "--primary-output", primary,
  "--secondary-output", secondary,
  path.join(root, input),
], { cwd: root, encoding: "utf8" });
if (result.status !== 0 || !fs.existsSync(primary) || !fs.existsSync(secondary)) {
  throw new Error(`wasm-split failed (${result.status}):\n${result.stdout ?? ""}${result.stderr ?? ""}`);
}
const digest = (file) => crypto.createHash("sha256").update(fs.readFileSync(file)).digest("hex");
const variant = input.includes("/pthread/") ? "pthread" : "single";
if (fs.existsSync(path.join(root, manifestPath))) {
  const manifestFile = path.join(root, manifestPath);
  const manifest = JSON.parse(fs.readFileSync(manifestFile, "utf8"));
  const debug = manifest.modules?.find((entry) => entry.id === "debug-incremental");
  const secondaryEntry = manifest.modules?.find((entry) => entry.id === "debug-incremental-secondary");
  if (debug?.resources?.[variant]) {
    debug.resources[variant].sha256 = digest(path.join(root, input));
    debug.resources[variant].url = `/${input.replace(/^web\/app\/public\//u, "")}`;
  }
  if (secondaryEntry?.resources?.[variant]) {
    secondaryEntry.resources[variant].fileName = path.basename(secondary);
    secondaryEntry.resources[variant].url = `/${path.relative(path.join(root, "web/app/public"), secondary).replaceAll(path.sep, "/")}`;
    secondaryEntry.resources[variant].sha256 = digest(secondary);
  }
  fs.writeFileSync(manifestFile, `${JSON.stringify(manifest, null, 2)}\n`);
}
console.log(JSON.stringify({
  status: "PASS",
  input,
  splitFunctions: splitFunctions.split(",").filter(Boolean),
  primary: { path: path.relative(root, primary), bytes: fs.statSync(primary).size, sha256: digest(primary) },
  secondary: { path: path.relative(root, secondary), bytes: fs.statSync(secondary).size, sha256: digest(secondary) },
}, null, 2));