function split_query(query) {
  query = query.split(' ');
  query = query.map(function (tag) { 
    return tag.trim();
  });
  query = query.filter(Boolean);
   
  return query;
}

function complete(field, suggestions, tag) {
  var query = $(field).val();

  query = split_query(query);
  if (query.length == 0)
    return;

  query[query.length - 1] = tag + ' ';

  $(field).val(query.join(' '));

  $(suggestions).hide();
}

function suggest(suggestions, suggestion_content, field, query) {
  query = split_query(query);
  if (query.length == 0)
    return;

  query = query[query.length - 1];
  if (query.length < 2)
    return;

  if (query[query.length - 1] == ' ' || query[query.length - 1] == '-') {
    $(suggestions).hide();

    return;
  }
  
  api_unchecked('suggest', {tag: query}, function (data) {
    if (data.error !== undefined) {
      popup('danger', data.error);

      $(suggestions).hide();

      return;
    }

    $(suggestion_content).html('');

    for (var i = 0; i < data.tags_list.length; i++) {
      var html = '';

      html += '<a class="dropdown-item" onclick="complete(\'' + field + '\', \'' + suggestions + '\', \'' + data.tags_list[i] + '\');">';
      html += data.tags_list[i];
      html += '</a>';

      $(suggestion_content).append(html);
    }

    if (data.tags_list.length)
      $(suggestions).show();
  });
}