package com.utils;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.io.FileUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
/**
 * 文件上傳下載工具類
 *
 */
public class FileHelper {
  /**
   * 根據路徑確定目錄，沒有目錄，則創(chuàng)建目錄
   *
   * @param path
   */
  private static void createDir(String path) {
    File fileDir = new File(path);
    if (!fileDir.exists() && !fileDir.isDirectory()) {// 判斷/download目錄是否存在
      fileDir.mkdir();// 創(chuàng)建目錄
    }
  }
  /**
   * 將文件名解析成文件的上傳路徑
   *
   * @param fileName
   * @return 上傳到服務器的文件名
   */
  public static String transPath(String fileName, String path) {
    createDir(path);
    Date date = new Date();
    SimpleDateFormat dateformat = new SimpleDateFormat("yyyyMMddhhmmssSSS");// 定義到毫秒
    String nowStr = dateformat.format(date);
    String filenameStr = fileName.substring(0, fileName.lastIndexOf("."));// 去掉后綴的文件名
    String suffix = fileName.substring(fileName.lastIndexOf(".") + 1);// 后綴
    if (fileName.trim() != "") {// 如果名稱不為"",說明該文件存在，否則說明該文件不存在
      path += "\\" + filenameStr + nowStr + "." + suffix;// 定義上傳路徑
    }
    return path;
  }
  /**
   * 提醒文件下載
   *
   * @param fileName
   * @param path
   * @return
   */
  public static ResponseEntity<byte[]> downloadFile(String fileName, String path) {
    try {
      fileName = new String(fileName.getBytes("GB2312"), "ISO_8859_1");// 避免文件名中文不顯示
    } catch (UnsupportedEncodingException e1) {
      e1.printStackTrace();
    }
    File file = new File(path);
    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
    headers.setContentDispositionFormData("attachment", fileName);
    ResponseEntity<byte[]> byteArr = null;
    try {
      byteArr = new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), headers, HttpStatus.OK);
    } catch (IOException e) {
      e.printStackTrace();
    }
    return byteArr;
  }
  /**
   * 將輸入流中的數(shù)據寫入字節(jié)數(shù)組
   *
   * @param in
   * @return
   */
  public static byte[] inputStream2ByteArray(InputStream in, boolean isClose) {
    byte[] byteArray = null;
    try {
      int total = in.available();
      byteArray = new byte[total];
      in.read(byteArray);
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      if (isClose) {
        try {
          in.close();
        } catch (Exception e2) {
          System.out.println("關閉流失敗");
        }
      }
    }
    return byteArray;
  }
}