import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;

import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.ImageWriter;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.ImageOutputStream;


/**
 * 图像裁剪以及压缩处理工具类
 *
 * 主要针对动态的GIF格式图片裁剪之后，只出现一帧动态效果的现象提供解决方案
 *
 * 提供依赖三方包解决方案（针对GIF格式数据特征一一解析，进行编码解码操作）
 * 提供基于JDK Image I/O 的解决方案(JDK探索失败)
 *
 *
 * @author Andy
 * @see       GifDecoder.class
 * @see       AnimatedGifEncoder.class
 * @see       BufferedImage.class
 * @see    ImageIO.class
 * @see       ImageReader.class
 * @since 1.0 2011.12.21
 */
public class ImageCutterUtil {

    public enum IMAGE_FORMAT{
        BMP("bmp"),
        JPG("jpg"),
        WBMP("wbmp"),
        JPEG("jpeg"),
        PNG("png"),
        GIF("gif");
        
        private String value;
        IMAGE_FORMAT(String value){
            this.value = value;
        }
        public String getValue() {
            return value;
        }
        public void setValue(String value) {
            this.value = value;
        }
    }
    
    
    /**
     * 获取图片格式
     * @param file   图片文件
     * @return    图片格式
     */
    public static String getImageFormatName(File file)throws IOException{
        String formatName = null;
        
        ImageInputStream iis = ImageIO.createImageInputStream(file);
        Iterator<ImageReader> imageReader =  ImageIO.getImageReaders(iis);
        if(imageReader.hasNext()){
            ImageReader reader = imageReader.next();
            formatName = reader.getFormatName();
        }

        return formatName;
    }
    
    /*************************  基于三方包解决方案    *****************************/
    /**
     * 剪切图片
     *
     * @param source        待剪切图片路径
     * @param targetPath    裁剪后保存路径（默认为源路径）
     * @param x                起始横坐标
     * @param y                起始纵坐标
     * @param width            剪切宽度
     * @param height        剪切高度         
     *
     * @returns                   裁剪后保存路径（图片后缀根据图片本身类型生成）    
     * @throws IOException
     */
    public static String cutImage(String sourcePath , String targetPath , int x , int y , int width , int height) throws IOException{
        File file = new File(sourcePath);
        if(!file.exists()) {
            throw new IOException("not found the image：" + sourcePath);
        }
        if(null == targetPath || targetPath.isEmpty()) targetPath = sourcePath;
        
        String formatName = getImageFormatName(file);
        if(null == formatName) return targetPath;
        formatName = formatName.toLowerCase();
        
        // 防止图片后缀与图片本身类型不一致的情况
        String pathPrefix = getPathWithoutSuffix(targetPath);
        targetPath = pathPrefix + formatName;
        
        // GIF需要特殊处理
        if(IMAGE_FORMAT.GIF.getValue() == formatName){
            GifDecoder decoder = new GifDecoder();  
            int status = decoder.read(sourcePath);  
            if (status != GifDecoder.STATUS_OK) {  
                throw new IOException("read image " + sourcePath + " error!");  
            }

            AnimatedGifEncoder encoder = new AnimatedGifEncoder();
            encoder.start(targetPath);
            encoder.setRepeat(decoder.getLoopCount());  
            for (int i = 0; i < decoder.getFrameCount(); i ++) {  
                encoder.setDelay(decoder.getDelay(i));  
                BufferedImage childImage = decoder.getFrame(i);
                BufferedImage image = childImage.getSubimage(x, y, width, height);
                encoder.addFrame(image);  
            }  
            encoder.finish();
        }else{
            BufferedImage image = ImageIO.read(file);
            image = image.getSubimage(x, y, width, height);
            ImageIO.write(image, formatName, new File(targetPath));
        }
        
        return targetPath;
    }
    
    /**
     * 压缩图片
     * @param sourcePath       待压缩的图片路径
     * @param targetPath    压缩后图片路径（默认为初始路径）
     * @param width            压缩宽度
     * @param height        压缩高度
     *
     * @returns                   裁剪后保存路径（图片后缀根据图片本身类型生成）    
     * @throws IOException
     */
    public static String zoom(String sourcePath , String targetPath, int width , int height) throws IOException{
        File file = new File(sourcePath);
        if(!file.exists()) {
            throw new IOException("not found the image ：" + sourcePath);
        }
        if(null == targetPath || targetPath.isEmpty()) targetPath = sourcePath;
        
        String formatName = getImageFormatName(file);
        if(null == formatName) return targetPath;
        formatName = formatName.toLowerCase();
        
        // 防止图片后缀与图片本身类型不一致的情况
        String pathPrefix = getPathWithoutSuffix(targetPath);
        targetPath = pathPrefix + formatName;
        
        // GIF需要特殊处理
        if(IMAGE_FORMAT.GIF.getValue() == formatName){
            GifDecoder decoder = new GifDecoder();  
            int status = decoder.read(sourcePath);  
            if (status != GifDecoder.STATUS_OK) {  
                throw new IOException("read image " + sourcePath + " error!");  
            }

            AnimatedGifEncoder encoder = new AnimatedGifEncoder();
            encoder.start(targetPath);
            encoder.setRepeat(decoder.getLoopCount());  
            for (int i = 0; i < decoder.getFrameCount(); i ++) {  
                encoder.setDelay(decoder.getDelay(i));  
                BufferedImage image = zoom(decoder.getFrame(i), width , height);
                encoder.addFrame(image);  
            }  
            encoder.finish();
        }else{
            BufferedImage image = ImageIO.read(file);
            BufferedImage zoomImage = zoom(image , width , height);
            ImageIO.write(zoomImage, formatName, new File(targetPath));
        }
        
        return targetPath;
    }
    
    /*********************** 基于JDK 解决方案     ********************************/
    
    /**
     * 读取图片
     * @param file 图片文件
     * @return     图片数据
     * @throws IOException
     */
    public static BufferedImage[] readerImage(File file) throws IOException{
        BufferedImage sourceImage = ImageIO.read(file);
        BufferedImage[] images = null;
        ImageInputStream iis = ImageIO.createImageInputStream(file);
        Iterator<ImageReader> imageReaders = ImageIO.getImageReaders(iis);
        if(imageReaders.hasNext()){
            ImageReader reader = imageReaders.next();
            reader.setInput(iis);
            int imageNumber = reader.getNumImages(true);
            images = new BufferedImage[imageNumber];
            for (int i = 0; i < imageNumber; i++) {
                BufferedImage image = reader.read(i);
                if(sourceImage.getWidth() > image.getWidth() || sourceImage.getHeight() > image.getHeight()){
                    image = zoom(image, sourceImage.getWidth(), sourceImage.getHeight());
                }
                images[i] = image;
            }
            reader.dispose();
            iis.close();
        }
        return images;
    }
    
    /**
     * 根据要求处理图片
     *
     * @param images    图片数组
     * @param x            横向起始位置
     * @param y         纵向起始位置
     * @param width      宽度    
     * @param height    宽度
     * @return            处理后的图片数组
     * @throws Exception
     */
    public static BufferedImage[] processImage(BufferedImage[] images , int x , int y , int width , int height) throws Exception{
        if(null == images){
            return images;
        }
        BufferedImage[] oldImages = images;
        images = new BufferedImage[images.length];
        for (int i = 0; i < oldImages.length; i++) {
            BufferedImage image = oldImages[i];
            images[i] = image.getSubimage(x, y, width, height);
        }
        return images;
    }
    
    /**
     * 写入处理后的图片到file
     *
     * 图片后缀根据图片格式生成
     *
     * @param images        处理后的图片数据
     * @param formatName     图片格式
     * @param file            写入文件对象
     * @throws Exception
     */
    public static void writerImage(BufferedImage[] images ,  String formatName , File file) throws Exception{
        Iterator<ImageWriter> imageWriters = ImageIO.getImageWritersByFormatName(formatName);
        if(imageWriters.hasNext()){
            ImageWriter writer = imageWriters.next();
            String fileName = file.getName();
            int index = fileName.lastIndexOf(".");
            if(index > 0){
                fileName = fileName.substring(0, index + 1) + formatName;
            }
            String pathPrefix = getFilePrefixPath(file.getPath());
            File outFile = new File(pathPrefix + fileName);
            ImageOutputStream ios = ImageIO.createImageOutputStream(outFile);
            writer.setOutput(ios);
            
            if(writer.canWriteSequence()){
                writer.prepareWriteSequence(null);
                for (int i = 0; i < images.length; i++) {
                    BufferedImage childImage = images[i];
                    IIOImage image = new IIOImage(childImage, null , null);
                    writer.writeToSequence(image, null);
                }
                writer.endWriteSequence();
            }else{
                for (int i = 0; i < images.length; i++) {
                    writer.write(images[i]);
                }
            }
            
            writer.dispose();
            ios.close();
        }
    }
    
    /**
     * 剪切格式图片
     *
     * 基于JDK Image I/O解决方案
     *
     * @param sourceFile        待剪切图片文件对象
     * @param destFile                  裁剪后保存文件对象
     * @param x                    剪切横向起始位置
     * @param y                 剪切纵向起始位置
     * @param width              剪切宽度    
     * @param height            剪切宽度
     * @throws Exception
     */
    public static void cutImage(File sourceFile , File destFile, int x , int y , int width , int height) throws Exception{
        // 读取图片信息
        BufferedImage[] images = readerImage(sourceFile);
        // 处理图片
        images = processImage(images, x, y, width, height);
        // 获取文件后缀
        String formatName = getImageFormatName(sourceFile);
        destFile = new File(getPathWithoutSuffix(destFile.getPath()) + formatName);

        // 写入处理后的图片到文件
        writerImage(images, formatName , destFile);
    }
    
    
    
    /**
     * 获取系统支持的图片格式
     */
    public static void getOSSupportsStandardImageFormat(){
        String[] readerFormatName = ImageIO.getReaderFormatNames();
        String[] readerSuffixName = ImageIO.getReaderFileSuffixes();
        String[] readerMIMEType = ImageIO.getReaderMIMETypes();
        System.out.println("========================= OS supports reader ========================");
        System.out.println("OS supports reader format name :  " + Arrays.asList(readerFormatName));
        System.out.println("OS supports reader suffix name :  " + Arrays.asList(readerSuffixName));
        System.out.println("OS supports reader MIME type :  " + Arrays.asList(readerMIMEType));
        
        String[] writerFormatName = ImageIO.getWriterFormatNames();
        String[] writerSuffixName = ImageIO.getWriterFileSuffixes();
        String[] writerMIMEType = ImageIO.getWriterMIMETypes();
        
        System.out.println("========================= OS supports writer ========================");
        System.out.println("OS supports writer format name :  " + Arrays.asList(writerFormatName));
        System.out.println("OS supports writer suffix name :  " + Arrays.asList(writerSuffixName));
        System.out.println("OS supports writer MIME type :  " + Arrays.asList(writerMIMEType));
    }
    
    /**
     * 压缩图片
     * @param sourceImage    待压缩图片
     * @param width             压缩图片高度
     * @param heigt            压缩图片宽度
     */
    private static BufferedImage zoom(BufferedImage sourceImage , int width , int height){
        BufferedImage zoomImage = new BufferedImage(width, height, sourceImage.getType());
        Image image = sourceImage.getScaledInstance(width, height, Image.SCALE_SMOOTH);
        Graphics gc = zoomImage.getGraphics();
        gc.setColor(Color.WHITE);
        gc.drawImage( image , 0, 0, null);
        return zoomImage;
    }
    
    /**
     * 获取某个文件的前缀路径
     *
     * 不包含文件名的路径
     *
     * @param file   当前文件对象
     * @return
     * @throws IOException
     */
    public static String getFilePrefixPath(File file) throws IOException{
        String path = null;
        if(!file.exists()) {
            throw new IOException("not found the file !" );
        }
        String fileName = file.getName();
        path = file.getPath().replace(fileName, "");
        return path;
    }
    
    /**
     * 获取某个文件的前缀路径
     *
     * 不包含文件名的路径
     *
     * @param path   当前文件路径
     * @return         不包含文件名的路径
     * @throws Exception
     */
    public static String getFilePrefixPath(String path) throws Exception{
        if(null == path || path.isEmpty()) throw new Exception("文件路径为空！");
        int index = path.lastIndexOf(File.separator);
        if(index > 0){
            path = path.substring(0, index + 1);
        }
        return path;
    }
    
    /**
     * 获取不包含后缀的文件路径
     *
     * @param src
     * @return
     */
    public static String getPathWithoutSuffix(String src){
        String path = src;
        int index = path.lastIndexOf(".");
        if(index > 0){
            path = path.substring(0, index + 1);
        }
        return path;
    }
    
    /**
     * 获取文件名
     * @param filePath        文件路径
     * @return                文件名
     * @throws IOException
     */
    public static String getFileName(String filePath) throws IOException{
        File file = new File(filePath);
        if(!file.exists()) {
            throw new IOException("not found the file !" );
        }
        return file.getName();
    }
    
    /**
     * @param args
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        // 获取系统支持的图片格式
        //ImageCutterUtil.getOSSupportsStandardImageFormat();
        
        try {
            // 起始坐标，剪切大小
            int x = 100;
            int y = 75;
            int width = 100;
            int height = 100;
            // 参考图像大小
            int clientWidth = 300;
            int clientHeight = 250;
            
            
            File file = new File("D:\\PCM Project\\upload\\tmp\\1.gif");
            BufferedImage image = ImageIO.read(file);
            double destWidth = image.getWidth();
            double destHeight = image.getHeight();
            
            if(destWidth < width || destHeight < height)
                throw new Exception("源图大小小于截取图片大小!");
            
            double widthRatio = destWidth / clientWidth;
            double heightRatio = destHeight / clientHeight;
            
            x = Double.valueOf(x * widthRatio).intValue();
            y = Double.valueOf(y * heightRatio).intValue();
            width = Double.valueOf(width * widthRatio).intValue();
            height = Double.valueOf(height * heightRatio).intValue();
            
            System.out.println("裁剪大小  x:" + x + ",y:" + y + ",width:" + width + ",height:" + height);

            /************************ 基于三方包解决方案 *************************/
            String formatName = getImageFormatName(file);
            String pathSuffix = "." + formatName;
            String pathPrefix = getFilePrefixPath(file);
            String targetPath = pathPrefix  + System.currentTimeMillis() + pathSuffix;
            targetPath = ImageCutterUtil.cutImage(file.getPath(), targetPath, x , y , width, height);
            
            String bigTargetPath = pathPrefix  + System.currentTimeMillis() + pathSuffix;
            ImageCutterUtil.zoom(targetPath, bigTargetPath, 100, 100);
            
            String smallTargetPath = pathPrefix  + System.currentTimeMillis() + pathSuffix;
            ImageCutterUtil.zoom(targetPath, smallTargetPath, 50, 50);
            
            /************************ 基于JDK Image I/O 解决方案(JDK探索失败) *************************/
//            File destFile = new File(targetPath);
//            ImageCutterUtil.cutImage(file, destFile, x, y, width, height);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}