package com.example.demo.utils;

import org.apache.commons.codec.binary.Base64;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Objects;

public class ImageToBase64Utils {

    private static String strNetImageToBase64;
    private static String strLocalImageToBase64;
    public static void main(String[] args) {
        //第一个:把网络图片装换成Base64
        String netImagePath = "http://sfm-passimg.oss-cn-shenzhen.aliyuncs.com/2005231240367755.jpg?Expires=4745882436&OSSAccessKeyId=LTAIIux1rFeEycax&Signature=c8LhNXaw951X2kyweGl2EB9wyNc%3D";
        //下面是网络图片转换Base64的方法
        String imageToBase64 =NetImageToBase64(netImagePath);

        //下面是本地图片转换Base64的方法
        // String imagePath = "C:\\Users\\Administrator\\IdeaProjects\\testdemo\\src\\main\\resources\\static\\testPictrue.jpg";

        // String imageToBase64 = LocalImageToBase64(imagePath);
        GenerateImage(imageToBase64,"D:\\test.jpg");
//        System.out.println(imageToBase64);
    }

    /**
     * 网络图片转换Base64的方法
     *
     * @param netImagePath
     */
    public static String NetImageToBase64(String netImagePath) {
        final ByteArrayOutputStream data = new ByteArrayOutputStream();
        try {
            // 创建URL
            URL url = new URL(netImagePath);
            final byte[] by = new byte[1024];
            // 创建链接
            final HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            conn.setConnectTimeout(5000);

            InputStream is = conn.getInputStream();
            // 将内容读取内存中
            int len = -1;
            while ((len = is.read(by)) != -1) {
                data.write(by, 0, len);
            }
            // 对字节数组Base64编码
            strNetImageToBase64 = new String(Base64.encodeBase64(data.toByteArray()));
//            System.out.println("网络图片转换Base64:" + strNetImageToBase64);
            // 关闭流
            is.close();


        } catch (IOException e) {
            e.printStackTrace();
        }

        return strNetImageToBase64;
    }


    /**
     * 本地图片转换Base64的方法
     *
     * @param imgPath
     * @return
     */

    public static String LocalImageToBase64(String imgPath) {
        byte[] data = null;
        // 读取图片字节数组
        try {
            InputStream in = new FileInputStream(imgPath);
            data = new byte[in.available()];
            in.read(data);
            in.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        // 返回Base64编码过的字节数组字符串
        strLocalImageToBase64 = new String(Base64.encodeBase64(Objects.requireNonNull(data)));
        return strLocalImageToBase64;
    }

    /**
     * base64转图片
     * @param base64str base64码
     * @param savePath 图片路径
     * @return
     */
    public static boolean GenerateImage(String base64str, String savePath) {
        //对字节数组字符串进行Base64解码并生成图片
        if (base64str == null) {
            return false;
        }
        try {
            //Base64解码
            byte[] b = Base64.decodeBase64(base64str);
            for (int i = 0; i < b.length; ++i) {
                //调整异常数据
                if (b[i] < 0) {
                    b[i] += 256;
                }
            }
            //生成jpeg图片
            OutputStream out = new FileOutputStream(savePath);
            out.write(b);
            out.flush();
            out.close();
            return true;
        } catch (Exception e) {
            return false;
        }
    }

}