프로그래머스 | 파일명정렬

function solution(files) {
  let fileWrap = files.map((file, index) => ({ file, index }));//{file:file, index:index}

  const compare = (a, b) => {
    const reg = /(\D*)([0-9]*)/i;
    const A = a.match(reg);//['abd123','abc'.'123']
    const B = b.match(reg);
    const compareHead = A[1].toLowerCase().localeCompare(B[1].toLowerCase());
    const compareNumber = (a, b) => {
      if (parseInt(a) > parseInt(b)) return 1;
      else if (parseInt(b) > parseInt(a)) return -1;
      else return 0
    }
    return compareHead === 0 ? compareNumber(A[2], B[2]) : compareHead;
  }
  fileWrap.sort((a, b) => {
    let result = compare(a.file, b.file)
    return result === 0 ? a.index - b.index : result
  })
  return fileWrap.map(e => e.file);
}