import {ConfigContainer} from '../ConfigContainer';
import {DIContainer} from '../../di/DIContainer';
import * as Path from 'path';
import {ConfigException} from '../error/ConfigException';
import {Reflection} from '../../core/Reflection';

/**
 * Config decorator expect a file name under process.cwd() + 'config'
 * @param fileNameOrPath
 * @returns {(target:Function)=>undefined}
 * @constructor
 */
export function Config(fileNameOrPath: string) {

  let path;

  if (Path.isAbsolute(fileNameOrPath)) {
    path = fileNameOrPath;
  } else {
    path = Path.resolve(process.cwd(), 'config', fileNameOrPath);
  }

  return (target: Function) => {

    if (Path.extname(fileNameOrPath) !== '.json') {
      throw new ConfigException(`[TYPED] only support json config file`);
    }

    const params = Reflection.getParams(target);
    DIContainer.registerComponent(undefined, target, params);
    ConfigContainer.registerConfig(path);
  };
}