const fs = require('fs');
const path = require('path');

const PACKAGE_ROOT = path.resolve(__dirname, '..', '..', '..');

const OUTPUT_CATEGORIES = Object.freeze([
  'login',
  'api-calls',
  'subscription',
  'meetings',
  'docs',
  'messages',
  'smoke',
  'tmp'
]);

function outputsRoot() {
  const override = process.env.QIWEI_OUTPUTS_DIR;
  if (override && String(override).trim()) return path.resolve(String(override).trim());
  return path.join(PACKAGE_ROOT, 'outputs');
}

function ensureDir(dirPath) {
  fs.mkdirSync(dirPath, { recursive: true });
  return dirPath;
}

function assertCategory(category) {
  if (!OUTPUT_CATEGORIES.includes(category)) {
    throw new Error(`未知输出类别 "${category}"，允许的类别：${OUTPUT_CATEGORIES.join(', ')}`);
  }
  return category;
}

function slugify(value, fallback = 'run') {
  const slug = String(value || '')
    .trim()
    .toLowerCase()
    .replace(/[^a-z0-9\u4e00-\u9fa5]+/g, '-')
    .replace(/^-+|-+$/g, '')
    .slice(0, 60);
  return slug || fallback;
}

function dateStamp(date = new Date()) {
  return date.toISOString().slice(0, 10);
}

function timeStamp(date = new Date()) {
  return date.toISOString().slice(11, 19).replace(/:/g, '');
}

function categoryDir(category) {
  return ensureDir(path.join(outputsRoot(), assertCategory(category)));
}

function latestPath(category, filename) {
  return path.join(categoryDir(category), filename);
}

function createRunDir(category, slug, date = new Date()) {
  const dir = path.join(
    categoryDir(category),
    dateStamp(date),
    `${timeStamp(date)}-${slugify(slug)}`
  );
  return ensureDir(dir);
}

function writeRunManifest(runDir, manifest = {}) {
  const filePath = path.join(runDir, 'manifest.json');
  const body = {
    createdAt: new Date().toISOString(),
    ...manifest,
    files: (manifest.files || []).map(file => path.relative(runDir, path.resolve(runDir, file)))
  };
  fs.writeFileSync(filePath, JSON.stringify(body, null, 2), 'utf8');
  return filePath;
}

module.exports = {
  PACKAGE_ROOT,
  OUTPUT_CATEGORIES,
  outputsRoot,
  ensureDir,
  slugify,
  dateStamp,
  timeStamp,
  categoryDir,
  latestPath,
  createRunDir,
  writeRunManifest
};