@antv/g/es/css/parser/transform-origin.js

import { isString } from '../../utils';
import { CSSUnitValue } from '../cssom/CSSNumericValue';
import { parseLengthOrPercentage } from './dimension';
/**
 * @see https://developer.mozilla.org/zh-CN/docs/Web/CSS/transform-origin
 * eg. 'center' 'top left' '50px 50px'
 */

export function parseTransformOrigin(value) {
  if (isString(value)) {
    var values = value.split(' ');

    if (values.length === 1) {
      if (values[0] === 'top' || values[0] === 'bottom') {
        // 'top' -> 'center top'
        values[1] = values[0];
        values[0] = 'center';
      } else {
        // '50px' -> '50px center'
        values[1] = 'center';
      }
    }

    if (values.length !== 2) {
      return null;
    } // eg. center bottom


    return [parseLengthOrPercentage(convertKeyword2Percent(values[0])), parseLengthOrPercentage(convertKeyword2Percent(values[1]))];
  } else {
    return [new CSSUnitValue(value[0] || 0, 'px'), new CSSUnitValue(value[1] || 0, 'px')];
  }
}

function convertKeyword2Percent(keyword) {
  if (keyword === 'center') {
    return '50%';
  } else if (keyword === 'left' || keyword === 'top') {
    return '0';
  } else if (keyword === 'right' || keyword === 'bottom') {
    return '100%';
  }

  return keyword;
}