import { readdir, readFile, mkdir, writeFile, unlink } from "node:fs/promises";
import { fileURLToPath } from "node:url";
import { join } from "node:path";

const source = fileURLToPath(new URL("../database/migrations/", import.meta.url));
const target = fileURLToPath(new URL("../backend/internal/migrations/sql/", import.meta.url));
const check = process.argv.includes("--check");
if (process.argv.length > 3 || (process.argv.length === 3 && !check)) {
  throw new Error("Usage: node scripts/sync-go-migrations.mjs [--check]");
}
if (!check) await mkdir(target, { recursive: true });
const sourceFiles = (await readdir(source)).filter((name) => name.endsWith(".sql")).sort();
const targetFiles = (await readdir(target)).filter((name) => name.endsWith(".sql")).sort();
const sourceSet = new Set(sourceFiles);
const stale = targetFiles.filter((name) => !sourceSet.has(name));
if (check && stale.length) {
  throw new Error(`Go migration bundle has stale files: ${stale.join(", ")}; run npm run db:bundle`);
}
for (const name of stale) await unlink(join(target, name));
for (const name of sourceFiles) {
  const canonical = await readFile(join(source, name));
  let bundled;
  try {
    bundled = await readFile(join(target, name));
  } catch (error) {
    if (error.code !== "ENOENT") throw error;
  }
  if (bundled?.equals(canonical)) continue;
  if (check) throw new Error(`Go migration bundle differs at ${name}; run npm run db:bundle`);
  await writeFile(join(target, name), canonical);
}
console.log(check ? `Go migration bundle current (${sourceFiles.length} files)` : `Go migration bundle synchronized (${sourceFiles.length} files)`);