const { test } = require('node:test');
const assert = require('node:assert/strict');
const { execFileSync, spawnSync } = require('node:child_process');
const fs = require('node:fs');
const os = require('node:os');
const path = require('node:path');

const CLI = path.join(__dirname, '..', 'src', 'cli.js');
const TOKEN = 'stoke-secret-token-for-sync-tests';

function git(args, cwd) {
  return execFileSync('git', args, { cwd, encoding: 'utf8' }).trim();
}

function commit(directory, message, contents) {
  fs.writeFileSync(path.join(directory, 'content.txt'), `${contents}\n`);
  git(['add', 'content.txt'], directory);
  git(['-c', 'user.name=Tester', '-c', 'user.email=tester@example.com', 'commit', '-m', message], directory);
  return git(['rev-parse', 'HEAD'], directory);
}

function fixture() {
  const root = fs.mkdtempSync(path.join(os.tmpdir(), 'stoke-sync-test-'));
  const forgeRoot = path.join(root, 'forge');
  const forgeRepo = path.join(forgeRoot, 'o', 'r.git');
  const seed = path.join(root, 'seed');
  const upstreamWork = path.join(root, 'upstream-work');
  const upstreamRepo = path.join(root, 'upstream.git');
  fs.mkdirSync(path.dirname(forgeRepo), { recursive: true });

  git(['init', '-b', 'main', seed], root);
  const oldSha = commit(seed, 'initial', 'initial');
  git(['clone', '--bare', seed, forgeRepo], root);
  git(['clone', seed, upstreamWork], root);
  const newSha = commit(upstreamWork, 'upstream advance', 'advanced');
  git(['clone', '--bare', upstreamWork, upstreamRepo], root);

  const config = path.join(root, 'config.json');
  fs.writeFileSync(config, JSON.stringify({
    url: `file://${forgeRoot}`,
    token: TOKEN,
    login: 'tester',
  }));

  return {
    root,
    forgeRepo,
    upstreamRepo,
    config,
    oldSha,
    newSha,
    cleanup() {
      fs.rmSync(root, { recursive: true, force: true });
    },
  };
}

function runSync(fx, extra = []) {
  return spawnSync(process.execPath, [
    CLI,
    'repo',
    'sync',
    '-o', 'o',
    '-r', 'r',
    '--from', `file://${fx.upstreamRepo}`,
    '--branch', 'main',
    ...extra,
  ], {
    encoding: 'utf8',
    env: { ...process.env, STOKE_CONFIG_FILE: fx.config },
  });
}

test('repo sync fast-forwards an undiverged forge branch', () => {
  const fx = fixture();
  try {
    const result = runSync(fx);

    assert.equal(result.status, 0, result.stderr);
    assert.equal(git(['rev-parse', 'refs/heads/main'], fx.forgeRepo), fx.newSha);
    assert.match(result.stdout, new RegExp(`main ${fx.oldSha}\\.\\.${fx.newSha}`));
  } finally {
    fx.cleanup();
  }
});