jest-image-snapshot/src/image-composer.js

/*
 * Copyright (c) 2019 American Express Travel Related Services Company, Inc.
 *
 * Licensed 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.
 */

const getMaxImageSize = (images) => {
  let maxWidth = 0;
  let maxHeight = 0;

  images.forEach((image) => {
    if (image.imageWidth > maxWidth) {
      maxWidth = image.imageWidth;
    }

    if (image.imageHeight > maxHeight) {
      maxHeight = image.imageHeight;
    }
  });

  return {
    maxWidth,
    maxHeight,
  };
};

const ImageComposer = function ImageComposer(options = {}) {
  this.direction = options.direction || 'horizontal';
  this.images = [];

  return this;
};

ImageComposer.prototype.addImage = function addImage(imageData, imageWidth, imageHeight) {
  this.images.push({
    imageData,
    imageWidth,
    imageHeight,
  });

  return this;
};

ImageComposer.prototype.getParams = function getParams() {
  const { maxWidth, maxHeight } = getMaxImageSize(this.images);

  const compositeWidth = maxWidth * (this.direction === 'horizontal' ? this.images.length : 1);
  const compositeHeight = maxHeight * (this.direction === 'vertical' ? this.images.length : 1);
  const offsetX = this.direction === 'horizontal' ? maxWidth : 0;
  const offsetY = this.direction === 'vertical' ? maxHeight : 0;

  return {
    direction: this.direction,
    images: this.images,
    imagesCount: this.images.length,
    compositeWidth,
    compositeHeight,
    offsetX,
    offsetY,
  };
};

module.exports = ImageComposer;