/*
    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.io.OutputStream;
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 SEMI = 2;
  public static final int MITTEL = 3;
  public static final int GROSS = 4;

  public static final String[] GRNAME = {"-w", "-k", "-s", "-m", "-g"};
  public static final int[] GR = {120, 240, 500, 700, 1200};

  public void writeImageStream(Image image, int gr, String mimeType, OutputStream out) throws InterruptedException, IOException {
    ImageIO.write(getReducedImage(image, gr, mimeType), imgType(mimeType), out);
  }

  /**
   *
   * @param image
   * @param gr
   * @param mimeType
   * @param vName Name der verkleinerten Datei
   * @throws InterruptedException
   * @throws IOException
   */
  public void writeImageFile(Image image, int gr, String mimeType, String vName) throws InterruptedException, IOException {
    ImageIO.write(getReducedImage(image, gr, mimeType), imgType(mimeType), new File(vName));
  }

  private BufferedImage getReducedImage(Image image, int gr, String mimeType) throws InterruptedException, IOException {
    BufferedImage img;
    int q = 90;
    float sh = 0.f;
    if (mimeType.contains("jpeg")) {
      img = getReducedImage2(image, gr, gr, q, sh, false);
    } else {
      img = getReducedImage2(image, gr, gr, q, sh, true);
    }
    return img;
  }

  /**
   * 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 getReducedImage2(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(imageWidth > imageHeight) {
      // Querformat
      thumbHeight = (int) (thumbWidth / imageRatio);
    } else if(imageWidth == imageHeight) {
      // 1:1 kann so bleiben
    } else {
      // Hochformat
      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;
  }
  
  /**
   * 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);
  }
}