import { execFileSync } from 'child_process';
import fs from 'fs';
import os from 'os';
import path from 'path';

type LocalPackOptions = {
  projectRoot?: string;
  outputDir?: string;
  packageName?: string;
  version?: string;
};

export const createLocalPackageTarball = async (
  options: LocalPackOptions = {},
): Promise<string> => {
  const projectRoot = options.projectRoot ?? process.cwd();
  const outputDir = options.outputDir ?? projectRoot;
  const packageJsonPath = path.join(projectRoot, 'package.json');
  const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf-8')) as {
    version?: string;
  };
  const version = options.version ?? packageJson.version;

  if (!version) {
    throw new Error('Unable to determine package version from package.json.');
  }

  const packageName = options.packageName ?? 'test-uniswap-position-quoter';
  const tempDir = fs.mkdtempSync(
    path.join(os.tmpdir(), 'uniswap-position-quoter-pack-'),
  );

  execFileSync('npm', ['pack', '--silent', '--pack-destination', tempDir], {
    cwd: projectRoot,
    stdio: 'pipe',
  });

  const tarballCandidates = fs
    .readdirSync(tempDir)
    .filter((fileName) => fileName.endsWith('.tgz'));

  if (tarballCandidates.length !== 1) {
    fs.rmSync(tempDir, { recursive: true, force: true });
    throw new Error('Unexpected npm pack output. Expected a single .tgz file.');
  }

  const tarballName = `${packageName}-v${version}.tgz`;
  const sourceTarballPath = path.join(tempDir, tarballCandidates[0]);
  const outputTarballPath = path.join(outputDir, tarballName);

  fs.renameSync(sourceTarballPath, outputTarballPath);
  fs.rmSync(tempDir, { recursive: true, force: true });

  return outputTarballPath;
};

const run = async (): Promise<void> => {
  const tarballPath = await createLocalPackageTarball({
    projectRoot: process.cwd(),
  });
  process.stdout.write(`${tarballPath}\n`);
};

if (require.main === module) {
  run().catch((error: Error) => {
    process.stderr.write(`${error.message}\n`);
    process.exitCode = 1;
  });
}