import path from 'node:path';
import { fileURLToPath } from 'node:url';
import { get_env } from './env.js';

function must_get(key) {
  const v = get_env(key);
  if (v === undefined || v === null || v === '') {
    throw new Error(`缺少配置 ${key}`);
  }
  return v;
}

function get_bool(key, default_value) {
  const v = get_env(key);
  if (v === undefined || v === null || v === '') {
    return default_value;
  }
  return String(v).toLowerCase() === 'true';
}

function get_int(key, default_value) {
  const v = get_env(key);
  if (v === undefined || v === null || v === '') {
    return default_value;
  }
  const n = Number(v);
  if (Number.isNaN(n)) {
    throw new Error(`配置 ${key} 必须是数字`);
  }
  return n;
}

let cached = null;

export function get_app_config() {
  if (cached) {
    return cached;
  }

  const __filename = fileURLToPath(import.meta.url);
  const __dirname = path.dirname(__filename);

  cached = {
    mysql: {
      host: must_get('MYSQL_HOST'),
      port: get_int('MYSQL_PORT', 3306),
      user: must_get('MYSQL_USER'),
      password: must_get('MYSQL_PASSWORD'),
      database: must_get('MYSQL_DATABASE')
    },
    server: {
      port: get_int('SERVER_PORT', 38080)
    },
    crawler: {
      crx_src_path: must_get('CRX_SRC_PATH'),
      action_timeout_ms: get_int('ACTION_TIMEOUT_MS', 300000),
      puppeteer_headless: get_bool('PUPPETEER_HEADLESS', false),
      chrome_executable_path: (get_env('CHROME_EXECUTABLE_PATH') || '').trim() || path.resolve(__dirname, '../../chrome-win/chrome.exe'),
      log_invoke_action: get_bool('LOG_INVOKE_ACTION', true)
    }
  };

  return cached;
}