package com.test.service;

 import java.io.File;

 import java.io.InputStream;

 import java.io.RandomAccessFile;

 import java.net.HttpURLConnection;

 import java.net.URL;

 import java.text.NumberFormat;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.springframework.beans.factory.annotation.Value;

 import org.springframework.stereotype.Component;

 /**

  * <p>

  *     文件下载,可以支持断点续传

  *     暂未使用

  * </p>

  *  @author

  *  @version 1.0

  * */

 @Component

 public class DownloadOnly {

     private static final Logger logger = LoggerFactory.getLogger(DownloadOnly.class);

     @Value("${onair.download.ddxc:true}")

     boolean ddxc = true;

     int startIndex = 0;

     long downloadSize = 0;

     boolean downloadFinish = false;

     int totleSize = 0;

     public boolean download(String url,String file_path,int downloadTimeout){

         //起一个线程 检测下载进度

         new Thread(new Runnable() {

             @Override

             public void run() {

                 try {

                      NumberFormat nt = NumberFormat.getPercentInstance();

                       //设置百分数精确度3即保留三位小数

                      nt.setMinimumFractionDigits(1);

                     while(!downloadFinish){

                         Thread.sleep(30000);

                         logger.debug("已下载大小{},进度{}",getDownloadSize(),nt.format(getDownloadSize()* 1.0 /totleSize));

                     }

                 } catch (InterruptedException e) {

                     e.printStackTrace();

                 }

             }

         }).start();

         logger.info("下载文件：源路径{},目标路径：{}",url,file_path);

         RandomAccessFile raf = null;

         InputStream in = null;

         try {

             URL file_url = new URL(url);

             HttpURLConnection conn = (HttpURLConnection)file_url.openConnection();

             conn.setConnectTimeout(downloadTimeout);

             conn.setRequestMethod("GET");

             File tmpFile = new File(file_path+"_tmp");

             if(ddxc){

                 if(tmpFile.exists() && tmpFile.isFile()){

                     downloadSize = tmpFile.length();

                     startIndex = (int)downloadSize;

                 }

                 conn.setRequestProperty("Range", "bytes=" + startIndex + "-");

             }else{

                 if(tmpFile.exists() && tmpFile.isFile())

                     tmpFile.delete();

             }

             int status = conn.getResponseCode();

             totleSize = (int)downloadSize + conn.getContentLength();

             logger.info("文件总大小{}，下载请求获得的返回状态码：{},需要下载的大小{}",totleSize,status,totleSize-downloadSize);

             if(status== 200 || status == 206 ){

                 raf = new RandomAccessFile(tmpFile, "rwd");

                 raf.seek(startIndex);

                 in = conn.getInputStream();

                 byte[] buffer = new byte[1024];

                 int size = 0;

                 while((size=in.read(buffer)) !=-1 ){

                     raf.write(buffer, 0, size);

                     downloadSize += size;

                 }

                 raf.close();

                 in.close();

                 File dest = new File(file_path);

                 return tmpFile.renameTo(dest);

             }

         } catch (Throwable e) {

             logger.error("文件下载失败：{}",e.getMessage(),e);

         }finally {

             downloadFinish = true; //下载完成或中断

         }

         return false;

     }

     public long getDownloadSize() {

         return downloadSize;

     }

     public static void main(String[] args) {

         DownloadOnly downloadOnly = new DownloadOnly();

     }

 }