package com.googosoft.until;

import java.io.BufferedInputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.net.HttpURLConnection;

import java.net.URL;

import java.util.ArrayList;

import java.util.Date;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import javax.servlet.http.HttpServletRequest;

/**

 * @author sonyan

 * @version 2019年11月25日 下午2:12:32

 * @desc

 */

public class Test {

    /**

     * 将html中的图片下载到服务器，并且使用服务器上图片的地址替换图片的网络路径

     * @param html 要处理的html

     * @param request

     * @param uploadFolder 服务器上保存图片的目录

     * @return

     */

    public static String transHtml(String html,HttpServletRequest request,String uploadFolder){

        List<String> imgList = getImgStrList(html,request);

        for (String imgStr : imgList) {

            try {

                String newUrl = reSaveImage(imgStr, request,uploadFolder);

                html = html.replace(imgStr, newUrl);

            } catch (Exception e) {

                e.printStackTrace();

            }

        }

        return html;

    } 

    /**

     * 将指定的网络图片保存到本地指定目录

     * @param httpUrl 图片原来的网络路径

     * @param request

     * @param uploadFolder 服务器上保存图片的目录

     * @return httpUrl newPath

     */

    private static String reSaveImage(String httpUrl,  HttpServletRequest request,String uploadFolder){

        FileOutputStream out = null;

        BufferedInputStream in = null;

        HttpURLConnection connection = null;

        Map<String, Object> urlMap = new HashMap<>();

        byte[] buf = new byte[1024];

        int len = 0;

        try {

            URL url = new URL(httpUrl);

            connection = (HttpURLConnection) url.openConnection();

            connection.connect();

            in = new BufferedInputStream(connection.getInputStream());

            urlMap = getNewPath(httpUrl, request,uploadFolder);

            out = new FileOutputStream(urlMap.get("newPath").toString());

            while ((len = in.read(buf)) != -1) {

                out.write(buf, 0, len);

            }

            out.flush();

        } catch (Exception e) {

            e.printStackTrace();

        } finally {

            try {

                in.close();

                out.close();

                connection.disconnect();

            } catch (IOException e) {

                e.printStackTrace();

            }

        }

        return urlMap.get("newUrl").toString();

    }

    /**

     * 获取保存在服务器上的图片的实际存储地址以及访问地址

     * @param httpUrl 图片原来的网络路径

     * @param request

     * @param uploadFolder服务器上保存图片的目录

     * @return

     */

    private static Map<String, Object> getNewPath(String httpUrl, HttpServletRequest request,String uploadFolder) {

        Map<String, Object> relMap = new HashMap<>();

        String fileName = getFileName();

        String filefix = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();// 文件后缀

        fileName = UuidUtil.get32UUID() + "." + filefix;

        String prefix = getUrlPrefix(request) + "/iconimg/";

        relMap.put("newUrl", prefix + fileName);

        relMap.put("newPath", uploadFolder + fileName);

        return relMap;

    }

    /**

     * 设置图片的名称（时间+用户编号）

     * @return

     */

    private static String getFileName() {

        return "reload"+File.pathSeparator+new Date().getTime()+".jpg";

    }

    /**

     * 提取HTML字符串中的img

     * @param htmlStr 要处理的html字符串

     * @return

     */

    private static List<String> getImgStrList(String htmlStr,HttpServletRequest request) {

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

        String img = "";

        Pattern p_image;

        Matcher m_image;

        String regEx_img = "<img.*src\\s*=\\s*(.*?)[^>]*?>";

        p_image = Pattern.compile(regEx_img, Pattern.CASE_INSENSITIVE);

        m_image = p_image.matcher(htmlStr);

        while (m_image.find()) {

            img = m_image.group();

            Matcher m = Pattern.compile("src\\s*=\\s*\"?(.*?)(\"|>|\\s+)").matcher(img);

            while (m.find()) {

                String path = m.group(1);

                if(!path.startsWith(getUrlPrefix(request))){

                    list.add(handleSrc(path));

                }

            }

        }

        return list;

    }

    /**

     * 去除src路径中的前后引号

     * @param src 图片的src路径

     * @return

     */

    private static String handleSrc(String src) {

        if (src != null) {

            if (src.startsWith("'")|| src.startsWith("\"")) {

                return src.substring(1, src.length());

            }

            if (src.endsWith("'")|| src.endsWith("\"")) {

                return src.substring(0, src.length());

            }

        }

        return src;

    }

    /**

     * 获取网站的URL

     * @param request

     * @return 例如：http://192.168.11.3:8089

     */

    public static String getUrlPrefix(HttpServletRequest request) {

        StringBuffer str = new StringBuffer();

        str.append(request.getScheme());

        str.append("://");

        str.append(request.getServerName());

        if (80 != request.getServerPort()) {

            str.append(":" + request.getServerPort());

        }

        str.append(request.getContextPath());

        return str.toString();

    }

}