/*
 * This is eMonocot, a global online biodiversity information resource.
 *
 * Copyright © 2011–2015 The Board of Trustees of the Royal Botanic Gardens, Kew and The University of Oxford
 *
 * eMonocot is free software: you can redistribute it and/or modify it under the terms of the
 * GNU Affero General Public License as published by the Free Software Foundation, either version 3
 * of the License, or (at your option) any later version.
 *
 * eMonocot is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * The complete text of the GNU Affero General Public License is in the source repository as the file
 * ‘COPYING’.  It is also available from <http://www.gnu.org/licenses/>.
 */
package org.emonocot.harvest.media;

import java.io.File;

import org.apache.sanselan.ImageInfo;
import org.apache.sanselan.Sanselan;
import org.emonocot.model.Image;
import org.emonocot.model.constants.AnnotationCode;
import org.emonocot.model.constants.AnnotationType;
import org.im4java.core.IMOperation;
import org.im4java.core.MogrifyCmd;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.batch.item.ItemProcessor;

/**
 *
 * @author ben
 *
 */
public class ImageResizerImpl implements ItemProcessor<Image, Image>, ImageResizer {

	private Logger logger = LoggerFactory.getLogger(ImageResizerImpl.class);

	private final Integer MAX_IMAGE_DIMENSION = 1000;

	private String searchPath;

	private String imageDirectory;

	private ImageAnnotator imageAnnotator;

	public final void setImageMagickSearchPath(final String imageMagickSearchPath) {
		this.searchPath = imageMagickSearchPath;
	}

	public final void setImageDirectory(final String newImageDirectory) {
		this.imageDirectory = newImageDirectory;
	}

	/**
	 * @param imageAnnotator the imageAnnotator to set
	 */
	public void setImageAnnotator(ImageAnnotator imageAnnotator) {
		this.imageAnnotator = imageAnnotator;
	}

	/* (non-Javadoc)
	 * @see org.emonocot.harvest.media.ImageResizer#process(org.emonocot.model.Image)
	 */
	@Override
	public final Image process(final Image image) throws Exception {

		String imageFileName = imageDirectory + File.separatorChar  + image.getId() + '.' + image.getFormat();
		File file = new File(imageFileName);
		if(!file.exists()) {
			logger.warn("File does not exist in image directory, skipping");
			imageAnnotator.annotate(image, AnnotationType.Error, AnnotationCode.BadData, "The local file was not found, so cannot be resized");
		} else {
			try {
				ImageInfo imageInfo = Sanselan.getImageInfo(file);
				Integer width = new Integer(imageInfo.getWidth());
				Integer height = new Integer(imageInfo.getHeight());
				logger.debug("Image " + imageFileName + " dimensions: " + width + " x " + height);

				if (width > MAX_IMAGE_DIMENSION || height > MAX_IMAGE_DIMENSION) {

					// shrink to no larger than MAX_IMAGE_DIMENSION * MAX_IMAGE_DIMENSION
					MogrifyCmd mogrify = new MogrifyCmd();
					if (searchPath != null) {
						mogrify.setSearchPath(searchPath);
					}
					IMOperation resize = new IMOperation();
					resize.addImage(imageFileName);
					logger.debug("resizing to no larger than " + MAX_IMAGE_DIMENSION.intValue()  + " * " + MAX_IMAGE_DIMENSION.intValue());
					resize.resize(MAX_IMAGE_DIMENSION.intValue(), MAX_IMAGE_DIMENSION.intValue(),'>');
					resize.addImage(imageFileName);
					mogrify.run(resize);

				} else {
					logger.info("No need to resize image as it is smaller than " + MAX_IMAGE_DIMENSION + "px x " + MAX_IMAGE_DIMENSION + "px");
				}
			} catch (Exception e) {
				logger.error("There was an error resizing the image", e);
				imageAnnotator.annotate(image, AnnotationType.Error, AnnotationCode.BadData, "The file could not be resized");
			}
		}
		return image;
	}
}