package com.juick.server.util;

import org.apache.commons.io.FilenameUtils;
import org.apache.commons.imaging.ImageReadException;
import org.apache.commons.imaging.Imaging;
import org.apache.commons.imaging.common.ImageMetadata;
import org.apache.commons.imaging.formats.jpeg.JpegImageMetadata;
import org.apache.commons.imaging.formats.tiff.TiffField;
import org.apache.commons.imaging.formats.tiff.constants.TiffTagConstants;
import org.imgscalr.Scalr;
import org.imgscalr.Scalr.Rotation;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.File;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;

public class ImageUtils {

/**
 * Returns <code>BufferedImage</code>, same as <code>ImageIO.read()</code> does.
 *
 * <p>JPEG images with EXIF metadata are rotated according to Orientation tag.
 *
 * @param imageFile a <code>File</code> to read from.
 */
    private static BufferedImage readImageWithOrientation(File imageFile)
            throws IOException {

        BufferedImage image = ImageIO.read(imageFile);
        if (!FilenameUtils.getExtension(imageFile.getName()).equals("jpg")) {
            return image;
        }

        try {
            ImageMetadata metadata = Imaging.getMetadata(imageFile);

            if (metadata instanceof JpegImageMetadata) {
                JpegImageMetadata jpegMetadata = (JpegImageMetadata) metadata;
                TiffField orientationField = jpegMetadata.findEXIFValue(TiffTagConstants.TIFF_TAG_ORIENTATION);

                if (orientationField != null) {
                    int orientation = orientationField.getIntValue();
                    switch (orientation) {
                        case TiffTagConstants.ORIENTATION_VALUE_ROTATE_90_CW:
                            image = Scalr.rotate(image, Rotation.CW_90);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_ROTATE_180:
                            image = Scalr.rotate(image, Rotation.CW_180);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_ROTATE_270_CW:
                            image = Scalr.rotate(image, Rotation.CW_270);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_MIRROR_HORIZONTAL:
                            image = Scalr.rotate(image, Rotation.FLIP_HORZ);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_MIRROR_VERTICAL:
                            image = Scalr.rotate(image, Rotation.FLIP_VERT);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_MIRROR_HORIZONTAL_AND_ROTATE_90_CW:
                            image = Scalr.rotate(Scalr.rotate(image, Rotation.FLIP_HORZ), Rotation.CW_90);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_MIRROR_HORIZONTAL_AND_ROTATE_270_CW:
                            image = Scalr.rotate(Scalr.rotate(image, Rotation.FLIP_HORZ), Rotation.CW_270);
                            break;
                        case TiffTagConstants.ORIENTATION_VALUE_HORIZONTAL_NORMAL:
                        default:
                            // do nothing
                            break;
                    }
                }
            }
        } catch (ImageReadException e) {
            // failed to read metadata.
            // nothing to do here, return image as is.
        }

        return image;
    }

    /**
     * Move attached image from temp folder to image folder.
     * Create preview images in corresponding folders.
     *
     * @param tempFilename   Name of the image file in the temp folder.
     * @param outputFilename Name that will be used in the image folder.
     * @param tmpDir         Path string for the temp folder.
     * @param imgDir         Path string for the image folder.
     */
    public static void saveImageWithPreviews(String tempFilename, String outputFilename, String tmpDir, String imgDir)
            throws IOException {
        String ext = FilenameUtils.getExtension(outputFilename);

        Path outputImagePath = Paths.get(imgDir, "p", outputFilename);
        Files.move(Paths.get(tmpDir, tempFilename), outputImagePath);
        BufferedImage originalImage = readImageWithOrientation(outputImagePath.toFile());

        int width = originalImage.getWidth();
        int height = originalImage.getHeight();
        int maxDimension = (width > height) ? width : height;
        BufferedImage image1024 = (maxDimension > 1024) ? Scalr.resize(originalImage, 1024) : originalImage;
        BufferedImage image0512 = (maxDimension > 512) ? Scalr.resize(originalImage, 512) : originalImage;
        BufferedImage image0160 = (maxDimension > 160) ? Scalr.resize(originalImage, 160) : originalImage;
        ImageIO.write(image1024, ext, Paths.get(imgDir, "photos-1024", outputFilename).toFile());
        ImageIO.write(image0512, ext, Paths.get(imgDir, "photos-512", outputFilename).toFile());
        ImageIO.write(image0160, ext, Paths.get(imgDir, "ps", outputFilename).toFile());
    }

    /**
     * Save new avatar in all required sizes.
     *
     * @param tempFilename Name of the image file in the temp folder.
     * @param uid          User id that is used to build image file names.
     * @param tmpDir       Path string for the temp folder.
     * @param imgDir       Path string for the image folder.
     */
    public static void saveAvatar(String tempFilename, int uid, String tmpDir, String imgDir)
            throws IOException {
        String ext = FilenameUtils.getExtension(tempFilename);
        String originalName = String.format("%s.%s", uid, ext);
        Path originalPath = Paths.get(imgDir, "ao", originalName);
        Files.move(Paths.get(tmpDir, tempFilename), originalPath, StandardCopyOption.REPLACE_EXISTING);
        BufferedImage originalImage = ImageIO.read(originalPath.toFile());

        String targetExt = "png";
        String targetName = String.format("%s.%s", uid, targetExt);
        ImageIO.write(Scalr.resize(originalImage, 96), targetExt, Paths.get(imgDir, "a", targetName).toFile());
        ImageIO.write(Scalr.resize(originalImage, 32), targetExt, Paths.get(imgDir, "as", targetName).toFile());
    }
}