@evg-b/evg-ui/dist/utils/calcMaxSizeRatio.js

EVG-UI library inspired by Material Design.

import _classCallCheck from '@babel/runtime/helpers/classCallCheck';
import _createClass from '@babel/runtime/helpers/createClass';

var RatioImg = /*#__PURE__*/function () {
  function RatioImg(width, height) {
    _classCallCheck(this, RatioImg);

    this.coefficientAnamorphismW = Number((width / height).toFixed(5));
    this.coefficientAnamorphismH = Number((height / width).toFixed(5));
  }
  /*
      @param size - размер нового отрезка
             mod  - 'w' | 'h' - ширина или высота
        @return {newWidth:int,newHeight:int}
  */


  _createClass(RatioImg, [{
    key: "reCaclNewRation",
    value: function reCaclNewRation(size, mod) {
      switch (mod) {
        case 'w':
          return {
            newWidth: size,
            newHeight: size / this.coefficientAnamorphismW | 0
          };

        case 'h':
          return {
            newWidth: size / this.coefficientAnamorphismH | 0,
            newHeight: size
          };
      }
    }
  }]);

  return RatioImg;
}();

function calcMaxSizeRatio (naturalWidth, naturalHeight, clientWidth, clientHeight) {
  var img = new RatioImg(naturalWidth, naturalHeight);
  var acceptableLimitWidth = clientWidth >= 1024 ? 1000 : clientWidth,
      acceptableLimitHeight = clientHeight * 0.9 | 0;
  var notFitLimitWidth = naturalWidth > acceptableLimitWidth,
      notFitLimitHeight = naturalHeight > acceptableLimitHeight;

  if (notFitLimitWidth && notFitLimitHeight) {
    var newSizetoH = img.reCaclNewRation(acceptableLimitHeight, 'h');

    if (newSizetoH.newWidth > acceptableLimitWidth) {
      return img.reCaclNewRation(acceptableLimitWidth, 'w');
    } else {
      return newSizetoH;
    }
  } else if (!notFitLimitWidth && !notFitLimitHeight) {
    return img.reCaclNewRation(naturalWidth, 'w');
  }

  if (notFitLimitWidth) {
    return img.reCaclNewRation(acceptableLimitWidth, 'w');
  }

  if (notFitLimitHeight) {
    return img.reCaclNewRation(acceptableLimitHeight, 'h');
  }
}

export default calcMaxSizeRatio;