import { chmod, mkdir, readFile, writeFile } from "node:fs/promises";
import { join } from "node:path";
import { reproRun } from "../../helpers/repro-run.js";

const LOKI_VERSION = "v2.7.3";

// returns path to statically compiled binary
export async function buildLoki(): Promise<string> {
  const dir = "cache/loki";
  await mkdir(dir, { recursive: true });
  const versionFile = join(dir, "version");
  const output = join(dir, "rootfs/loki");
  try {
    if ((await readFile(versionFile, "utf-8")) === LOKI_VERSION) return output;
  } catch {}

  {
    const buildScript = join(dir, "build");
    await writeFile(
      buildScript,
      `#!/bin/sh -e
runprint() {
  echo "==> $@"
  "$@"
}

runprint apk add --quiet git go make libc-dev bash

git config --global advice.detachedHead false
# TODO: cachear clon de repo
runprint git clone https://github.com/grafana/loki --branch '${LOKI_VERSION}' --depth 1 --single-branch
cd loki

runprint make -j1 GOMOD=readonly logcli loki
mv cmd/loki/loki /loki
`
    );
    await chmod(buildScript, 0o700);
  }
  await reproRun({
    cwd: dir,
    command: "/src/build",
    cache: [
      "/home/repro/.cache/go-build",
      "/home/repro/go",
      "/home/repro/.npm",
    ],
  });
  await writeFile(versionFile, LOKI_VERSION);

  return output;
}