/*
    Dateiverwaltung - File management in your browser
    Copyright (C) 2017 Ulrich Hilger, http://uhilger.de

    This program 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.

    This program 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.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

package de.uhilger.wbx;

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.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.FileNameMap;
import java.net.URLConnection;
import javax.imageio.ImageIO;

/**
 * Methoden zur Verkleinerung von Bildern
 */
public class Bild {
  
  public static final int WINZIG = 0;
  public static final int KLEIN = 1;
  public static final int MITTEL = 2;
  public static final int GROSS = 3;
  
  public static final String[] GRNAME = {"-w", "-k", "-m", "-g"};
  public static final int[] GR = {120, 240, 700, 1200};
  
  /**
   * 
   * @param image
   * @param gr
   * @param mimeType
   * @param oName Name der Originaldatei
   * @param vName Name der verkleinerten Datei
   * @throws InterruptedException
   * @throws IOException 
   */
  public void writeImageFile(Image image, int gr, String mimeType, String oName, String vName) throws InterruptedException, IOException {
    int q = 90;
    float sh = 0.f;
    //String mimeType = photo.getMimetype();
    BufferedImage img;
    if(mimeType.contains("jpeg")) {
      img = getReducedImage(image, gr, gr, q, sh, false);
    } else {
      img = getReducedImage(image, gr, gr, q, sh, true);
    }
    ImageIO.write(img, imgType(mimeType), new File(vName));
  }

  /**
   * Eine in Groesse und Qualitaet verringerte Bilddatei erzeugen
   * @param image  Ablageort und Name der Bilddatei
   * @param width  neue Breite
   * @param height  neue hoehe
   * @param quality neue Qualitaet (0 - 100)
   * @param factor Faktor fuer Schaerfe / Unschaerfe (z.B. -0.15f fuer leichte Unschaerfe, 0.05f fuer leichtes Nachschaerfen)
   * @param withTransparency ob Transparenz benoetigt wird
   * @return neues, in Groesse und Qualitaet entsprechend verringertes Bild
   * @throws java.lang.InterruptedException
   * @throws java.io.FileNotFoundException
   */
  public BufferedImage getReducedImage(Image image, int width, int height, int quality, float factor, boolean withTransparency) 
  throws InterruptedException, FileNotFoundException, IOException {

    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);
		}

		// draw original image to thumbnail image object and
		// scale it to the new size on-the-fly
		//BufferedImage thumbImage = new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_RGB);
    BufferedImage thumbImage;
    if(withTransparency) {
  	  thumbImage = new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_ARGB);
    } else {
      thumbImage = new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_RGB);
    }
		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 != 0.f) {
			float[] array = {0, factor, 0, factor, 1-(factor*4), factor, 0, factor, 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)
    
    return thumbImage;
  }
  
  public String imgType(String mimeType) {
    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";
    }
    return imgType;
  }
  
  /**
   * 
   * @param v Bild.WINZIG .. Bild.GROSS
   * @return L&auml;nge der l&auml;ngsten Kante in Bildpunkten
   */
  public int getVariantenGroesse(int v) {
    return GR[v];
  }
  
  public String getVariantenName(int v) {
    return GRNAME[v];
  }
  
  public String getMimeType(File file) {
    String absName = file.getAbsolutePath();
    FileNameMap fileNameMap = URLConnection.getFileNameMap();
    return fileNameMap.getContentTypeFor("file://" + absName);    
  }
}