function make_friendly_link(s) {
  if (typeof s == "undefined") {
    return;
  }

  var i=0,uni1,arr1;
  var newclean=s;
  uni1 = 'à|á|ạ|ả|ã|â|ầ|ấ|ậ|ẩ|ẫ|ă|ằ|ắ|ặ|ẳ|ẵ|À|Á|Ạ|Ả|Ã|Â|Ầ|Ấ|Ậ|Ẩ|Ẫ|Ă|Ằ|Ắ|Ặ|Ẳ|Ẵ|A';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'a');

  uni1 = 'è|é|ẹ|ẻ|ẽ|ê|ề|ế|ệ|ể|ễ|È|É|Ẹ|Ẻ|Ẽ|Ê|Ề|Ế|Ệ|Ể|Ễ|E';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'e');

  uni1 = 'ì|í|ị|ỉ|ĩ|Ì|Í|Ị|Ỉ|Ĩ|I';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'i');

  uni1 = 'ò|ó|ọ|ỏ|õ|ô|ồ|ố|ộ|ổ|ỗ|ơ|ờ|ớ|ợ|ở|ỡ|Ò|Ó|Ọ|Ỏ|Õ|Ô|Ồ|Ố|Ộ|Ổ|Ỗ|Ơ|Ờ|Ớ|Ợ|Ở|Ỡ|O';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'o');

  uni1 = 'ù|ú|ụ|ủ|ũ|ư|ừ|ứ|ự|ử|ữ|Ù|Ú|Ụ|Ủ|Ũ|Ư|Ừ|Ứ|Ự|Ử|Ữ|U';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'u');

  uni1 = 'ỳ|ý|ỵ|ỷ|ỹ|Ỳ|Ý|Ỵ|Ỷ|Ỹ|Y';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'y');

  uni1 = 'd|Đ|D';
  arr1 = uni1.split('|');
  for (i=0; i<uni1.length; i++) newclean = newclean.replace(uni1[i],'d');

  newclean = newclean.toLowerCase()
  ret = newclean.replace(/[\&]/g, '-and-').replace(/[^a-zA-Z0-9._-]/g, '-').replace(/[-]+/g, '-').replace(/-$/, '');

  return ret;
}