package com.sandu.common.file;

import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.ImageType;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.bytedeco.javacv.FFmpegFrameGrabber;
import org.bytedeco.javacv.Frame;
import org.bytedeco.javacv.Java2DFrameConverter;
import org.springframework.context.annotation.Configuration;


import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;

@Configuration
public class FileToThumbnail {
    /**
     * <p>Title: thumbnailImage</p>
     * <p>Description: 根据图片路径生成缩略图 </p>
     *
     * @param imagePath 原图片路径
     * @param w         缩略图宽
     * @param h         缩略图高
     * @param prevfix   生成缩略图的前缀
     * @param force     是否强制按照宽高生成缩略图(如果为false，则生成最佳比例缩略图)
     */
    public void getThumbnailForPic(String imagePath, int w, int h, String prevfix, boolean force) throws IOException {
        File imgFile = new File(imagePath);
        if (imgFile.exists()) {
            // ImageIO 支持的图片类型 : [BMP, bmp, jpg, JPG, wbmp, jpeg, png, PNG, JPEG, WBMP, GIF, gif]
            String types = Arrays.toString(ImageIO.getReaderFormatNames());
            String suffix = null;
            // 获取图片后缀
            if (imgFile.getName().indexOf(".") > -1) {
                suffix = imgFile.getName().substring(imgFile.getName().lastIndexOf(".") + 1);
            }
            // 类型和图片后缀全部小写，然后判断后缀是否合法
            if (suffix == null || types.toLowerCase().indexOf(suffix.toLowerCase()) < 0) {
                System.out.println("Sorry, the image suffix is illegal. the standard image suffix is {}." + types);
                return;
            }
            System.out.println("target image's size, width:{" + w + "}, height:{" + h + "}.");
            Image img = ImageIO.read(imgFile);
            if (!force) {
                // 根据原图与要求的缩略图比例，找到最合适的缩略图比例
                int width = img.getWidth(null);
                int height = img.getHeight(null);
                if ((width * 1.0) / w < (height * 1.0) / h) {
                    if (width > w) {
                        h = Integer.parseInt(new java.text.DecimalFormat("0").format(height * w / (width * 1.0)));
                    }
                } else {
                    if (height > h) {
                        w = Integer.parseInt(new java.text.DecimalFormat("0").format(width * h / (height * 1.0)));
                    }
                }
            }
            BufferedImage bi = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
            Graphics g = bi.getGraphics();
            g.drawImage(img, 0, 0, w, h, Color.LIGHT_GRAY, null);
            g.dispose();
            String p = imgFile.getPath();
            // 将图片保存在原目录并加上前缀
            ImageIO.write(bi, suffix, new File(p.substring(0, p.lastIndexOf(File.separator)) + File.separator + prevfix + imgFile.getName()));
        }
    }


    /**
     * 通过PDFbox生成文件的缩略图
     *
     * @param filePath：文件路径
     * @param outPath：输出图片路径
     * @throws IOException
     */
    public String getThumbnailForPdf(String filePath, String outPath) throws IOException {
        // 利用PdfBox生成图像
        PDDocument pdDocument = PDDocument.load(new File(filePath));
        PDFRenderer renderer = new PDFRenderer(pdDocument);
        // 构造图片
        BufferedImage img_temp = renderer.renderImageWithDPI(0, 30, ImageType.RGB);
        ImageIO.write(img_temp, "png", new File(outPath));
        pdDocument.close();
        return outPath;
    }

    /**
     * @param sourcePath 保存路径
     * @return String 保存路径
     * @description //生成视频缩略图的URL地址
     */
    public String getThumbnailForVideo(InputStream inputStream, String sourcePath) throws IOException {
        File targetFile = new File(sourcePath);

        FFmpegFrameGrabber ff = new FFmpegFrameGrabber(inputStream);
        ff.start();
        // 视频总帧数
        int videoLength = ff.getLengthInFrames();
        Frame f = null;
        int i = 0;
        while (i < videoLength) {
            // 过滤前20帧,因为前20帧可能是全黑的
            // 这里看需求，也可以直接根据帧数取图片
            f = ff.grabFrame();
            if (i > 20 && f.image != null) {
                break;
            }
            i++;
        }
        int owidth = f.imageWidth;
        int oheight = f.imageHeight;
        // 对截取的帧进行等比例缩放
        int width = 300;
        int height = (int) (((double) width / owidth) * oheight);
        Java2DFrameConverter converter = new Java2DFrameConverter();
        BufferedImage fecthedImage = converter.getBufferedImage(f);
        BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR);
        bi.getGraphics().drawImage(fecthedImage.getScaledInstance(width, height, Image.SCALE_SMOOTH),
                0, 0, null);
        ImageIO.write(bi, "png", targetFile);
        // 查看stop源码会自动关流
        ff.stop();
        return sourcePath;

    }


}