import globby from 'globby';
import ignore from 'ignore';
import fs from 'fs';
import { join, relative } from 'path';

function transformOptions(
  result,
  item,
  key
) {
  result.push(`--${key}`);
  if (typeof item[key] !== 'boolean') {
    result.push(item[key]);
  }
}

export function getExistFile(
  { cwd, files, returnRelative }
) {
  for (const file of files) {
    const absFilePath = join(cwd, file);
    if (fs.existsSync(absFilePath)) {
      return returnRelative ? file : absFilePath;
    }
  }
}

// 获取其他需要忽略的规则
function getIgnores(
  cwd: string
) {
  let ignores = [];

  globby
    .sync('**/.eslintignore', {
      ignore: ['**/node_modules/**'],
      cwd,
    })
    .forEach(file => {
      const result = fs
        .readFileSync(file, 'utf8')
        .split(/\r?\n/)
        .filter(Boolean)
        .filter(line => line.charAt(0) !== '#');
      ignores = ignores.concat(result);
    });
  return ignores;
}

export function endsWithArray(
  str,
  arr
) {
  return new RegExp(`${arr.join('$|')}$`).test(str);
}

export function getFiles(
  patterns: string[],
  cwd: string
) {
  const result = globby
    .sync(patterns, {
      gitignore: true,
      ignore: ['**/node_modules/**', '.git'],
      onlyFiles: true,
      dot: true
    })
    .map(item => {
      // ignore 包必须使用相对路径
      return relative(cwd, item);
    });

  return ignore()
    .add(getIgnores(cwd))
    .filter(result);
}

export function parseSubOptions(
  option: any
) {
  if (Array.isArray(option)) {
    return option
      .filter(item => typeof item === 'object')
      .reduce((result, item) => {
        const key = Object.keys(item)[0];
        transformOptions(result, item, key);
        return result;
      }, []);
  } else if (typeof option === 'object') {
    const result = [];
    Object.keys(option).forEach(key => {
      transformOptions(result, option, key);
    });
    return result;
  }
  return [];
}

export function getEsLintExtensions(options) {
  const index = options.indexOf('--ext');
  if (index !== -1) {
    return options[index + 1].split(',');
  }
  return ['.js', '.jsx'];
}