function add_part() {
  var part_table = document.getElementById('part-table');
  var model_part_html = document.getElementById('model_part').innerHTML;
  var part_num_hidden = document.getElementById('part_num');
  var part_num = 0;
  if (part_num_hidden.value) {
    part_num = parseInt(part_num_hidden.value);
  }
  var re = /%ind%/gi;
  var part_html = model_part_html.replace(re, part_num);
  part_num++;
  part_table.insertRow(part_num).insertCell(0).innerHTML = part_html;
  part_num_hidden.value = part_num;
}
 
function remove_part() {
  var part_num_hidden = document.getElementById('part_num');
  var part_num = parseInt(part_num_hidden.value);
  var part_table = document.getElementById('part-table');
  var last_ind = part_num - 1;
  var del_part_id = document.getElementById('goods_part_id_' + last_ind).value;
  var del_parts_hidden = document.getElementById('del_parts');
  del_parts_hidden.value += ',' + del_part_id;
  part_table.deleteRow(part_num);
  var part_num_hidden = document.getElementById('part_num');
  part_num_hidden.value = last_ind;
}

function check_all_parts(checked) {
  var parts = document.getElementsByName('parts');
  for (var i=parts.length-1; i>=0; --i) {
    parts[i].checked = checked;
  }
}