package jnpf.util;

import cn.hutool.core.net.URLEncodeUtil;
import jnpf.constant.GlobalConst;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.MediaType;
import org.springframework.http.MediaTypeFactory;

import jakarta.servlet.http.HttpServletResponse;
import org.springframework.util.StreamUtils;

import java.io.*;

@Slf4j
public class FileDownloadUtil {

    /**
     * 下载文件
     *
     * @param fileName 订单信息.pdf
     */
    public static void outFile(InputStream inputStream, String fileName) {
        HttpServletResponse response = ServletUtil.getResponse();
        //设置文件写出头部
        setDownloadHeader(response, fileName);
        //写出文件
        try {
            StreamUtils.copy(inputStream, response.getOutputStream());
        } catch (IOException e) {
            log.error("写出文件失败, {}, {}, {}", fileName, e.getMessage());
        }
    }

    /**
     * 下载文件
     *
     * @param bytes
     * @param fileName 订单信息.pdf
     */
    public static void outFile(byte[] bytes, String fileName) {
        HttpServletResponse response = ServletUtil.getResponse();
        //设置文件写出头部
        setDownloadHeader(response, fileName);
        //设置文件大小
        response.setContentLength(bytes.length);
        //写出文件
        try {
            StreamUtils.copy(bytes, response.getOutputStream());
        } catch (IOException e) {
            log.error("写出文件失败, {}, {}, {}", fileName, e.getMessage());
        }
    }


    /**
     * 显示文件
     */
    public static void flushFile(InputStream inputStream, String fileName) {
        HttpServletResponse response = ServletUtil.getResponse();
        setFlushHeader(response, fileName);
        //写出文件
        try {
            StreamUtils.copy(inputStream, response.getOutputStream());
        } catch (IOException e) {
            log.error("写出图片失败, {}, {}", fileName, e.getMessage());
        }
    }


    /**
     * 显示文件
     */
    public static void flushFile(byte[] bytes, String fileName) {
        if(bytes == null || bytes.length == 0) {
            return;
        }
        HttpServletResponse response = ServletUtil.getResponse();
        setFlushHeader(response, fileName);
        //设置文件大小
        response.setContentLength(bytes.length);
        //写出文件
        try {
            StreamUtils.copy(bytes, response.getOutputStream());
        } catch (IOException e) {
            log.error("写出图片失败, {}, {}", fileName, e.getMessage());
        }
    }



    /**
     * 下载文件
     *
     * @param fileName 订单信息.pdf
     */
    public static void setDownloadHeader(HttpServletResponse response, String fileName) {
        //设置文件类型
        setFlushHeader(response, fileName);

        //编码的文件名字,关于中文乱码的改造
//        String codeFileName = fileName;
//            String agent = request.getHeader("USER-AGENT").toLowerCase();
//            if (-1 != agent.indexOf("mozilla")) {
//                //火狐，谷歌
////                codeFileName = new String(fileName.getBytes("UTF-8"), "iso-8859-1");
//            }
        response.setHeader("Content-Disposition", "attachment;filename=" + URLEncodeUtil.encode(fileName, GlobalConst.DEFAULT_CHARSET));
    }

    /**
     * 下载文件
     *
     * @param fileName 订单信息.pdf
     */
    public static void setFlushHeader(HttpServletResponse response, String fileName) {
        //设置文件类型
        if (fileName != null && MediaTypeFactory.getMediaType(fileName).isPresent()) {
            response.setContentType(MediaTypeFactory.getMediaType(fileName).orElse(MediaType.ALL).toString());
        }
        response.setCharacterEncoding("UTF-8");
    }

}