import AJV from 'ajv';
import { relative } from 'path';
import slash from 'slash2';
import schema from './schema';
import { IConfig } from './types';
import { getExistFile } from './utils';

export const CONFIG_FILES = [
  'lotus-lint.config.js',
  'lotus-lint.config.ts'
];

function testDefault(obj) {
  return obj.default || obj;
}

function getUserConfig(
  { cwd }
): IConfig {

  const configFile = getExistFile({
    cwd,
    files: CONFIG_FILES,
    returnRelative: false,
  });

  if (configFile) {
    const userConfig = testDefault(require(configFile));
    const ajv = new AJV({ allErrors: true });
    const validate = ajv.compile(schema);
    const isValid = validate(schema);

    if (!isValid) {
      const errors = ajv.errors.map(({ dataPath, message }, index) => {
        return `${index + 1}. ${dataPath}${dataPath ? ' ' : ''}${message}`;
      });
      throw new Error(
        `Invalid options in ${slash(relative(cwd, configFile))} ${errors.join('\n')}`.trim(),
      );
    }
    return userConfig;
  }
  return {};
}

export default getUserConfig