import { chmod, mkdir, readFile, writeFile } from "node:fs/promises";
import { join } from "node:path";
import { execFile } from "./better-api.js";

export async function reproRun(opts: {
  // cwd stores the code available inside the container as /src, and also
  // cache/ and rootfs/
  cwd: string;
  command: string;
  cache?: string[];
}): Promise<void> {
  const run = execFile("repro-run", { cwd: opts.cwd });
  if (!run.child.stdin) throw false;
  run.child.stdin.write(
    JSON.stringify({
      Command: opts.command,
      Cache: opts.cache,
    })
  );
  run.child.stdin.end();
  run.child.stdout?.pipe(process.stdout);
  run.child.stderr?.pipe(process.stderr);
  await run;
}

export async function buildRepro<T>(
  cacheName: string,
  cacheKey: string,
  buildScript: string,
  run: (cwd: string) => Promise<void>,
  getArtifacts: (cwd: string) => T
): Promise<T> {
  const dir = join("cache", cacheName);
  await mkdir(dir, { recursive: true });
  const cacheKeyFile = join(dir, "version");
  const output = getArtifacts(dir);
  try {
    if ((await readFile(cacheKeyFile, "utf-8")) === cacheKey) return output;
  } catch {}

  {
    const buildScriptPath = join(dir, "build");
    await writeFile(buildScriptPath, buildScript);
    await chmod(buildScriptPath, 0o700);
  }
  await run(dir);
  await writeFile(cacheKeyFile, cacheKey);

  return output;
}