gethue/ko/bindings/ko.autogrowInput.js

Hue is an Open source SQL Query Editor for Databases/Warehouses

// Licensed to Cloudera, Inc. under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  Cloudera, Inc. licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

import $ from 'jquery';
import * as ko from 'knockout';

ko.bindingHandlers.autogrowInput = {
  init: function (element, valueAccessor) {
    const o = $.extend(
      {
        minWidth: 0,
        maxWidth: 1000,
        comfortZone: 70
      },
      valueAccessor()
    );

    const minWidth = o.minWidth || $(element).width();
    const input = $(element);
    const testSubject = $('<tester></tester>').css({
      position: 'absolute',
      top: -9999,
      left: -9999,
      width: 'auto',
      fontSize: input.css('fontSize'),
      fontFamily: input.css('fontFamily'),
      fontWeight: input.css('fontWeight'),
      letterSpacing: input.css('letterSpacing'),
      whiteSpace: 'nowrap'
    });
    let val = '';

    const check = function () {
      if (val === (val = input.val())) {
        return;
      }
      const escaped = val
        .replace(/&/g, '&amp;')
        .replace(/\s/g, ' ')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;');
      testSubject.html(escaped);
      const testerWidth = testSubject.width(),
        newWidth = testerWidth + o.comfortZone >= minWidth ? testerWidth + o.comfortZone : minWidth,
        currentWidth = input.width(),
        isValidWidthChange =
          (newWidth < currentWidth && newWidth >= minWidth) ||
          (newWidth > minWidth && newWidth < o.maxWidth);
      if (isValidWidthChange) {
        input.width(newWidth);
      }
    };
    testSubject.insertAfter(element);
    ko.utils.registerEventHandler(element, 'keyup keydown blur update', check);
  }
};