InlineAutoCropping.java

/*
 * #%L
 * wcm.io
 * %%
 * Copyright (C) 2019 wcm.io
 * %%
 * 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.
 * #L%
 */
package io.wcm.handler.mediasource.inline;

import java.util.Arrays;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import org.apache.commons.lang3.ObjectUtils;
import org.jetbrains.annotations.NotNull;

import io.wcm.handler.media.CropDimension;
import io.wcm.handler.media.Dimension;
import io.wcm.handler.media.MediaArgs;
import io.wcm.handler.media.format.MediaFormat;
import io.wcm.handler.media.impl.ImageTransformation;

/**
 * Helper class for calculating crop dimensions for auto-cropping.
 */
class InlineAutoCropping {

  private final Dimension imageDimension;
  private final MediaArgs mediaArgs;

  InlineAutoCropping(@NotNull Dimension imageDimension, @NotNull MediaArgs mediaArgs) {
    this.imageDimension = imageDimension;
    this.mediaArgs = mediaArgs;
  }

  public List<CropDimension> calculateAutoCropDimensions() {
    Stream<MediaFormat> mediaFormats = Arrays.stream(
        ObjectUtils.defaultIfNull(mediaArgs.getMediaFormats(), new MediaFormat[0]));
    return mediaFormats
        .map(this::calculateAutoCropDimension)
        .filter(Objects::nonNull)
        .collect(Collectors.toList());
  }

  private CropDimension calculateAutoCropDimension(@NotNull MediaFormat mediaFormat) {
    double ratio = mediaFormat.getRatio();
    if (ratio > 0 && imageDimension.getWidth() > 0 && imageDimension.getHeight() > 0) {
      return ImageTransformation.calculateAutoCropDimension(imageDimension.getWidth(), imageDimension.getHeight(), ratio);
    }
    return null;
  }

}