package de.uhilger.bildhelfer;

import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.awt.image.ConvolveOp;
import java.awt.image.Kernel;
import java.awt.MediaTracker;
import java.awt.Container;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.FileNameMap;
import java.net.URLConnection;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriter;
import javax.imageio.ImageWriteParam;
import javax.imageio.stream.FileImageOutputStream;
import javax.imageio.IIOImage;

class Verkleinerer {

  private static final Logger logger = Logger.getLogger(Verkleinerer.class.getName());

  void verkleinern(String[] args) {
    int groesse = getIntFromArg(args[1], 1200);
    float qualitaet = getFloatFromArg(args[2], (float) 0.7);
    File eingangsOrdner = getFileFromArg(args[3]);
    if(eingangsOrdner == null) {
      logger.info("Eingangsordner konnte nicht bestimmt werden, Abbruch.");
      return;
    } else {
      logger.info("Eingangsordner " + eingangsOrdner);
    }
    File ausgabeOrdner = getFileFromArg(args[4]);
    if(ausgabeOrdner == null) {
      logger.info("Ausgabeordner konnte nicht bestimmt werden, Abbruch.");
      return;
    } else {
      logger.info("Ausgabeordner " + ausgabeOrdner);
    }
    dateienVerarbeiten(groesse, qualitaet, eingangsOrdner.getAbsolutePath(), ausgabeOrdner.getAbsolutePath());
  }

  private int getIntFromArg(String arg, int defaultValue) {
    try {
      int argValue = Integer.parseInt(arg);
      logger.info("Ausgabegroesse " + argValue);
      return argValue;
    } catch(Exception ex) {
      logger.info("Ausgabegroesse konnte nicht ermittelt werden, es wird der Standardwert " + defaultValue + " verwendet.");
      return defaultValue;
    }
  }

  private float getFloatFromArg(String arg, float defaultValue) {
    try {
      float argValue = Float.parseFloat(arg);
      logger.info("Ausgabequalitaet " + argValue);
      return argValue;
    } catch(Exception ex) {
      logger.info("Ausgabequalitaet konnte nicht ermittelt werden, es wird der Standardwert " + defaultValue + " verwendet.");
      return defaultValue;
    }
  }

  private File getFileFromArg(String arg) {
    try {
      File f = new File(arg);
      if(!f.exists()) {
        return null;
      } else {
        return f;
      }
    } catch(Exception ex) {
      logger.log(Level.SEVERE, ex.getLocalizedMessage(), ex);
      return null;
    }
  }


  private void dateienVerarbeiten(int gr, float quality, String inDirName, String outDirName) {
/*
	Java-Code zum Verkleinern von Bildern

	args[0] - Anzahl Pixel an der laengsten Kante
	args[1] - qualitaet JPEG, z.B. 0.75 fuer 75% des Originals
	args[2] - Eingangsordner
	args[3] - Ausgabeordner
*/

    FileNameMap fileNameMap = URLConnection.getFileNameMap();
    //int width = Integer.parseInt(args[0]);
    int width = gr;
    int height = width;
    //String inDirName = args[2];
    //String outDirName = args[3];
    File inFile = new File(inDirName);
    File[] fileList = inFile.listFiles();
    if(fileList != null && fileList.length > 0) {
      for(int i = 0; i < fileList.length; i++) {
        //System.out.println(fileList[i].getAbsolutePath());

        File outDir = new File(outDirName);
        File outFile = new File(outDir, fileList[i].getName());
        //System.out.println(outFile.getAbsolutePath());
        try {
          Image image = ImageIO.read(fileList[i]);
          MediaTracker mediaTracker = new MediaTracker(new Container());
          mediaTracker.addImage(image, 0);
          mediaTracker.waitForID(0);
          if (!mediaTracker.isErrorAny()) {

            //float quality = Float.parseFloat(args[1]);
            float factor = (float) 0.0;

            BufferedImage thumbImage;
            int imageWidth = image.getWidth(null);
            int imageHeight = image.getHeight(null);
            int thumbWidth = width;
            int thumbHeight = height;
            if(imageWidth < width) {
              thumbWidth = imageWidth;
            }
            if(imageHeight < height) {
              thumbHeight = imageHeight;
            }
            double thumbRatio = (double)thumbWidth / (double)thumbHeight;
            double imageRatio = (double)imageWidth / (double)imageHeight;
            if (thumbRatio < imageRatio) {
              thumbHeight = (int)(thumbWidth / imageRatio);
            }
            else {
              thumbWidth = (int)(thumbHeight * imageRatio);
            }

            String mimeType = fileNameMap.getContentTypeFor("file://" + fileList[i].getAbsolutePath());

            // draw original image to thumbnail image object and
            // scale it to the new size on-the-fly
            if(mimeType.contains("jpeg") || mimeType.contains("png")) {
              thumbImage = new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_RGB);
            } else {
              thumbImage = new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_ARGB);
            }
            Graphics2D graphics2D = thumbImage.createGraphics();
            graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
            graphics2D.drawImage(image, 0, 0, thumbWidth, thumbHeight, null);

            // 30.7.2007: sharpening hinzugefuegt (Anfang)
            //float factor = -0.15f; // minus = sharpen, plus = soften
            //float[] sharpenArray = {0, -1, 0, -1, 5, -1, 0, -1, 0};
        /*
          30.6.2013: sharpening als Weichmacher nur, wenn Bild < 400
        */
        /*if(thumbWidth < 400 || thumbHeight < 400) {
          factor = 0.1f;
        }*/

            if(factor != (float) 0.0) {
              //float[] array = {0, factor, 0, factor, 1-(factor*4), factor, 0, factor, 0};
              float[] array = new float[9];
              array[0] = 0;
              array[1] = factor;
              array[2] = 0;
              array[3] = factor;
              array[4] = 1-(factor*4);
              array[5] = factor;
              array[6] = 0;
              array[7] = factor;
              array[8] = 0;
              Kernel kernel = new Kernel(3, 3, array);
              ConvolveOp cOp = new ConvolveOp(kernel, ConvolveOp.EDGE_NO_OP, null);
              thumbImage = cOp.filter(thumbImage, null);
            }
            // 30.7.2007: sharpening hinzugefuegt (Ende)

            String imgType;
            if(mimeType.contains("jpg")) {
              imgType = "jpg";
            } else if(mimeType.contains("jpeg")) {
              imgType = "jpg";
            } else if(mimeType.contains("png")) {
              imgType = "png";
            } else if(mimeType.contains("gif")) {
              imgType = "gif";
            } else {
              imgType = "jpg";
            }

				/*
					14.1.2018: Ausgabe um Qualitaetsparameter erweitert
					Beginn
				*/
            ImageWriter writer = ImageIO.getImageWritersByFormatName(imgType).next();
            ImageWriteParam iwp = writer.getDefaultWriteParam();
            iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
            iwp.setCompressionQuality(quality);
            writer.setOutput(new FileImageOutputStream(outFile));
            writer.write(null, new IIOImage(thumbImage, null, null), iwp);
            writer.dispose();
            /* 14.1.2018 Ende */
          }
        } catch (InterruptedException ex) {
          //System.out.println("Error: " + ex.getLocalizedMessage());
        } catch (FileNotFoundException e) {
          e.printStackTrace();
        } catch (IOException e) {
          e.printStackTrace();
        }
      }
    } else {
      //System.out.println("fileList is null or empty");
    }
  }
}