package org.webslinger.ext.image;

 import java.awt.Dimension;

 import java.awt.Point;

 import java.awt.Rectangle;

 import java.io.File;

 import java.io.InputStream;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.List;

 import java.util.ListIterator;

 import java.util.Map;

 import java.util.concurrent.CopyOnWriteArrayList;

 import static java.lang.Math.max;

 import static java.lang.Math.min;

 import javax.servlet.ServletException;

 import org.apache.commons.collections.Transformer;

 import org.apache.commons.lang.StringUtils;

 import org.apache.commons.vfs.FileContent;

 import org.apache.commons.vfs.FileObject;

 import org.webslinger.PathContext;

 import org.webslinger.TypeHandler;

 import org.webslinger.Webslinger;

 import org.webslinger.WebslingerServletContext;

 import org.webslinger.collections.CollectionUtil;

 import org.webslinger.commons.vfs.VFSUtil;

 import org.webslinger.io.IOUtil;

 import org.webslinger.lang.ConcurrentCache;

 import static org.webslinger.lang.NumberUtil.parseInt;

 import org.webslinger.servlet.Binary;

 import org.webslinger.util.GeneratedResult;

 import org.webslinger.util.TTLObject;

 public class ImageUtils {

     private static final ImageSizeCache imageBoxes = new ImageSizeCache(ImageUtils.class, "imageBoxes", null);

     protected FileObject root;

     public static String runImageMagick(String[] commandAndArgs) throws InterruptedException, IOException {

         ProcessBuilder builder = new ProcessBuilder(commandAndArgs);

         Map<String, String> env = builder.environment();

         env.remove("DISPLAY");

         Process process = builder

                             .directory(new File("/"))

                             .redirectErrorStream(true)

                             .start();

         String output = IOUtil.readString(process.getInputStream());

         process.waitFor();

         return process.exitValue() == 0 ? output : null;

     }

     private static Rectangle getImageBox(String prefix, InputStream in) throws InterruptedException, IOException {

         File tmpFile = File.createTempFile(prefix, ".tmp");

         tmpFile.deleteOnExit();

         try {

             IOUtil.copy(in, true, tmpFile);

             return getImageBox(tmpFile);

         } finally {

             tmpFile.delete();

         }

     }

     public static Rectangle getImageBoxCached(File file) throws InterruptedException, IOException {

         return imageBoxes.get(file).getObject();

     }

     public static Rectangle getImageBox(File file) throws InterruptedException, IOException {

         String output = runImageMagick(new String[] {"identify", file.getPath()});

         if (output == null) return null;

         //  "/tmp/identify50184.image JPEG 800x600 DirectClass 82kb"

         String[] dimensions;

         try {

             dimensions = (output.substring(file.getPath().length() + 1).split(" "))[1].split("x");

         } catch (RuntimeException e) {

             System.err.println("error parsing(" + file + "->" + output + ")");

             throw e;

         }

         return new Rectangle(0, 0, Integer.parseInt(dimensions[0]), Integer.parseInt(dimensions[1]));

     }

     public static void convertType(File file, String type) throws InterruptedException, IOException {

         if (type != null) runImageMagick(new String[] {"mogrify", "-format", type, file.getPath()});

     }

     public static Rectangle getImageBox(FileObject file) throws InterruptedException, IOException {

         File localFile;

         try {

             localFile = VFSUtil.findLocalFile(file);

         } catch (IOException e) {

             localFile = null;

         }

         if (localFile != null) return getImageBoxCached(localFile);

         return getImageBox("image-box-commons-vfs-", file.getContent().getInputStream());

     }

     public static Rectangle getImageBox(Binary.FileContent content) throws InterruptedException, IOException {

         return getImageBox(content.getFile());

     }

     public static Rectangle getImageBox(Binary.Content content) throws InterruptedException, IOException {

         if (content instanceof Binary.FileContent) return getImageBox((Binary.FileContent) content);

         return getImageBox("image-box-binary-content-", content.getInputStream());

     }

     public static Rectangle cropImage(File file, Rectangle cropArea) throws InterruptedException, IOException {

         return cropImage(file, cropArea, false);

     }

     public static Rectangle cropImage(File file, Rectangle cropArea, boolean preview) throws InterruptedException, IOException {

         Rectangle imageBox = getImageBox(file);

         if (imageBox == null) return null;

         cropArea = imageBox.intersection(cropArea);

         if (!preview) {

             runImageMagick(new String[] {"mogrify", "-crop", ((int) cropArea.getWidth()) + "x" + ((int) cropArea.getHeight()) + "+" + ((int) cropArea.getX()) + "+" + ((int) cropArea.getY()), file.getPath()});

             return cropArea;

         }

         int x0 = (int) cropArea.getX();

         int y0 = (int) cropArea.getY();

         int x1 = (int) (cropArea.getX() + cropArea.getWidth());

         int y1 = (int) (cropArea.getY() + cropArea.getHeight());

         int width = (int) imageBox.getWidth();

         int height = (int) imageBox.getHeight();

         /*

          *

          * 0        x0        x1         width

          * /--------+---------+---------\ 0

          * |........|.........|.........|

          * |........|...   ...|.........|

          * |........|... C ...|.........|

          * |........|...   ...|.........|

          * |........|.........|.........|

          * |........+---------+.........| y0

          * |........|         |.........| 

          * |..   ...|         |...   ...|

          * |.. A ...|         |... B ...|

          * |..   ...|         |...   ...|

          * |........|         |.........|

          * |........|         |.........| y1

          * |........+---------+.........|

          * |........|.........|.........|

          * |........|...   ...|.........|

          * |........|... D ...|.........|

          * |........|...   ...|.........|

          * |........|.........|.........|

          * \--------+---------+---------/ height

          */

         int[][] rectangles = new int[][] {

             {0, 0,      x0, height},

             {x1, 0,     width, height},

             {x0, 0,     x1, y0},

             {x0, y1,    x1, height},

         };

         List<String> args = new ArrayList<String>();

         args.addAll(Arrays.asList("mogrify", "-fill", "#0000003f"));

         for (int[] r: rectangles) {

             args.add("-draw");

             args.add("rectangle " + r[0] + "," + r[1] + " " + r[2] + "," + r[3]);

         }

         args.add(file.getPath());

         runImageMagick(args.toArray(new String[args.size()]));

         return imageBox;

     }

     public static Rectangle resizeImage(File file, int width, int height) throws InterruptedException, IOException {

         StringBuilder sizeArg = new StringBuilder();

         if (width > 0) sizeArg.append(width);

         sizeArg.append('x');

         if (height > 0) sizeArg.append(height);

         sizeArg.append('!');

         if (runImageMagick(new String[] {"mogrify", "-resize", sizeArg.toString(), file.getPath()}) == null) return null;

         return getImageBox(file);

     }

     public static Rectangle constrainImage(File file, int width, int height) throws InterruptedException, IOException {

         StringBuilder sizeArg = new StringBuilder();

         if (width > 0) sizeArg.append(width);

         sizeArg.append('x');

         if (height > 0) sizeArg.append(height);

         sizeArg.append('>');

         runImageMagick(new String[] {"mogrify", "-resize", sizeArg.toString(), file.getPath()});

         Rectangle box = getImageBox(file);

         if (box == null) return null;

         if (box.getWidth() <= width && box.getHeight() <= height) return box;

         if (box.getWidth() < width) {

             return resizeImage(file, (int) box.getWidth(), height);

         } else {

             return resizeImage(file, width, (int) box.getHeight());

         }

     }

     public static Rectangle constrainImage(File file, String fillColor, float wantedRatio) throws InterruptedException, IOException {

         Rectangle imageBox = getImageBox(file);

         int width = (int) imageBox.getWidth(), height = (int) imageBox.getHeight();

         float gotRatio = (float) height / width;

         int pageWidth = width, pageHeight = height;

         if (width > height) {

             if (wantedRatio > gotRatio) {

                 pageHeight = (int) (width * wantedRatio);

             } else {

                 pageWidth = (int) (height / wantedRatio);

             }

         } else {

             if (wantedRatio > gotRatio) {

                 pageWidth = (int) (height / wantedRatio);

             } else {

                 pageHeight = (int) (width * wantedRatio);

             }

         }

         if (pageWidth == width && pageHeight == height) return imageBox;

         int x = (pageWidth - width) / 2;

         int y = (pageHeight - height) / 2;

         List<String> args = new ArrayList<String>();

         args.add("mogrify");

         args.add("-fill"); args.add(fillColor);

         args.add("-page"); args.add(pageWidth + "x" + pageHeight);

         args.add("-extent"); args.add(pageWidth + "x" + pageHeight);

         args.add("-draw"); args.add("image Over " + x + "," + y + " " + width + "x" + height + " '" + file.getPath() + "'");

         args.add("-fill"); args.add(fillColor);

         args.add("-draw"); args.add("rectangle 0,0 " + pageWidth + "," + y);

         args.add("-fill"); args.add(fillColor);

         args.add("-draw"); args.add("rectangle 0,0 " + x + "," + pageHeight);

         args.add("-fill"); args.add(fillColor);

         args.add("-draw"); args.add("rectangle 0," + (pageHeight - y - 1) + " " + pageWidth + "," + pageHeight);

         args.add("-fill"); args.add(fillColor);

         args.add("-draw"); args.add("rectangle " + (pageWidth - x - 1) + ",0 " + pageWidth + "," + pageHeight);

         args.add(file.getPath());

         runImageMagick(args.toArray(new String[args.size()]));

         imageBox = getImageBox(file);

         return imageBox;

     }

     public static Rectangle constrainBox(int width, int height, int containerWidth, int containerHeight) {

         int boxHeight, boxWidth;

         if (width > containerWidth) {

             if (height > containerHeight) {

                 double widthRatio = (float) containerWidth / width;

                 double heightRatio = (float) containerHeight / height;

                 if (widthRatio > heightRatio) {

                     boxHeight = containerHeight;

                     boxWidth = (int) (width * heightRatio);

                 } else {

                     boxHeight = (int) (height * widthRatio);

                     boxWidth = containerWidth;

                 }

             } else {

                 double widthRatio = (float) containerWidth / width;

                 boxHeight = (int) (height * widthRatio);

                 boxWidth = containerWidth;

             }

         } else {

             double widthRatio = (float) containerWidth / width;

             double heightRatio = (float) containerHeight / height;

             if (widthRatio > heightRatio) {

                 boxHeight = containerHeight;

                 boxWidth = (int) (width * heightRatio);

             } else {

                 boxHeight = (int) (height * widthRatio);

                 boxWidth = containerWidth;

             }

         }

         return new Rectangle(0, 0, boxWidth, boxHeight);

     }

 }