package com.deloitte.system.service;

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSONArray;
import com.common.aws.util.S3Util;
import com.common.core.constant.GlobalConst;
import com.common.core.enums.ResultCodeEnum;
import com.common.core.exception.BizException;
import com.common.core.utils.UUID;
import com.common.core.utils.*;
import com.common.redis.util.RedisUtil;
import com.deloitte.system.request.FileRequest;
import com.j256.simplemagic.ContentInfoUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.codec.binary.Base64;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;
import software.amazon.awssdk.core.ResponseBytes;
import software.amazon.awssdk.services.s3.model.GetObjectResponse;
import software.amazon.awssdk.services.s3.model.S3Exception;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.bind.DatatypeConverter;
import java.io.*;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.text.SimpleDateFormat;
import java.util.*;

import static com.common.core.constant.GlobalConst.PIPL_UNCONFIRM_FILE;

@Slf4j
@Service
public class FileService {
    @Autowired
    private RedisUtil redisUtil;
    @Value("${salesforce.referer}")
    private String refererUrl;
    @Value("${aws.s3.bucketName}")
    private String bucketName;

    public String upload(String txId,FileRequest fileRequest){
        log.info("上传文件txId:"+txId);
        String key=uploadFile(fileRequest);
        String keyName = PIPL_UNCONFIRM_FILE + txId;
        redisUtil.set(keyName, new JSONArray(Arrays.asList(key)), GlobalConst.DATA_EXPIRE);
        return key;
    }

    public List<String> batchUpload(String txId, List<FileRequest> fileList) {
        log.info("上传文件txId:"+txId);
        List<String> keys=new ArrayList<>();
        try {
            fileList.forEach(fileRequest -> {
                String key = uploadFile(fileRequest);
                keys.add(key);
            });
            String keyName = PIPL_UNCONFIRM_FILE + txId;
            redisUtil.set(keyName, new JSONArray((List)keys), GlobalConst.DATA_EXPIRE);
        }catch (Exception e){
            this.cleanS3File(keys);
            throw e;
        }
        return keys;
    }

    public String uploadFile(FileRequest fileRequest){
        if (fileRequest == null) {
            throw new BizException(ResultCodeEnum.NO_DATA);
        }
        log.info("fileName:{}", fileRequest.getFileName());
        //文件大小限制，最大单文件30M
        if(fileRequest.getSize()>31457280){
            throw new BizException(ResultCodeEnum.FILE_SIZE_EXCEED);
        }
        if(fileRequest.getFile().startsWith("base64,")){
            String contentType= ContentInfoUtil.findExtensionMatch(fileRequest.getFileName())==null?
                    "text/plain": ContentInfoUtil.findExtensionMatch(fileRequest.getFileName()).getMimeType();
            fileRequest.setFile("data:"+contentType+";"+fileRequest.getFile());
        }
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
        String oldFileName = fileRequest.getFileName();
        String suffix=oldFileName.lastIndexOf(".")==-1?"":oldFileName.substring(oldFileName.lastIndexOf("."));
        String newFileName = UUID.randomUUID().toString().replace("-","")+suffix;
        String key = sdf.format(new Date()) + "/" + newFileName;
        // 将文件base64存入缓存
        MultipartFile multipartFile = null;
        try {
            multipartFile = BASE64DecodedMultipartFile.base64ToMultipart(fileRequest.getFile());
        } catch (IOException e) {
            log.error("上传文件失败：",e);
        }
        if (multipartFile == null) {
            throw new BizException("未找到文件");
        }
        String bucketName = SpringContextUtils.getEnvParam("aws.s3.bucketName");
        S3Util.uploadFile(multipartFile, key,bucketName);
        return key;
    }

    public String uploadFileNoSize(FileRequest fileRequest){
        if (fileRequest == null) {
            throw new BizException(ResultCodeEnum.NO_DATA);
        }
        log.info("fileName:{}", fileRequest.getFileName());
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
        String oldFileName = fileRequest.getFileName();
        String suffix=oldFileName.lastIndexOf(".")==-1?"":oldFileName.substring(oldFileName.lastIndexOf("."));
        String newFileName = UUID.randomUUID().toString().replace("-","")+suffix;
        String key = sdf.format(new Date()) + "/" + newFileName;
        // 将文件base64存入缓存
        MultipartFile multipartFile = null;
        try {
            multipartFile = BASE64DecodedMultipartFile.base64ToMultipart(fileRequest.getFile());
        } catch (IOException e) {
            log.error("上传文件失败：",e);
        }
        if (multipartFile == null) {
            throw new BizException("未找到文件");
        }
        String bucketName = SpringContextUtils.getEnvParam("aws.s3.bucketName");
        S3Util.uploadFile(multipartFile, key,bucketName);
        return key;
    }

    public void cleanS3File(Collection<String> keyList){
        if (!keyList.isEmpty()){
            String bucketName = SpringContextUtils.getEnvParam("aws.s3.bucketName");
            S3Util.deleteByKeys(new ArrayList<String>(keyList),bucketName);
        }
    }

    private boolean checkReferer(String referer){
        String[] refererUrls=refererUrl.split(",");
        for (String str : refererUrls) {
            if(str.equalsIgnoreCase(referer)||str.substring(0,str.length()-1).equalsIgnoreCase(referer)){
                return true;
            }
        }
        return false;
    }

    public void preview(HttpServletRequest request,HttpServletResponse response,String key){
        String referer = request.getHeader("Referer");
        if (StrUtil.isBlank(referer)) {
            throw new BizException(ResultCodeEnum.NO_PERMISSION);
        }
        //referer 截取
        String replace = referer.replace("https://", "");
        String newReferer = "https://"+replace.substring(0, replace.indexOf("/")+1);
        if (!checkReferer(newReferer)) {
            throw new BizException(ResultCodeEnum.NO_PERMISSION);
        }
        String fileName = key.substring(key.lastIndexOf("/")+1);
        log.info("文件预览key:{},fileName:{}",key,fileName);
        OutputStream out = null;
        try {
            response.setCharacterEncoding("utf-8");
            String s = ContentInfoUtil.findExtensionMatch(fileName).getMimeType();
            log.info("文件预览key:{},contentType:{}",key,s);
            if (StrUtil.isNotBlank(s)) {
                response.setContentType(s);
            } else{
                response.setContentType(MediaType.ALL_VALUE);
            }
            String agent = request.getHeader("User-Agent");
            if(agent.toLowerCase().contains("firefox")) {
                response.setHeader("Content-Disposition", "inline; filename==?UTF-8?B?" + new String(Base64.encodeBase64(fileName.getBytes("UTF-8")))+"?=");
            }else {
                response.setHeader("Content-Disposition", "inline; filename=" +  new String(fileName.getBytes("gbk"),"iso8859-1"));
            }
            ResponseBytes<GetObjectResponse> objectBytes = S3Util.downloadFile(key,bucketName);
            InputStream inputStream = objectBytes.asInputStream();
            BufferedInputStream bufInputStream = new BufferedInputStream(inputStream);
            out = response.getOutputStream();
            byte[] buf = new byte[1024];
            int len;
            while ((len = bufInputStream.read(buf)) > 0) {
                out.write(buf, 0, len);
            }
            response.flushBuffer();
            out.close();
        } catch (IOException e) {
            log.error("文件预览失败：",e);
            throw new BizException(ResultCodeEnum.RT_ERROR);
        }catch (S3Exception e) {
            log.error("文件预览失败：",e);
            throw new BizException(e.getMessage());
        }

    }
    
    public void download(HttpServletRequest request,HttpServletResponse response,String key){
        String referer = request.getHeader("Referer");

        log.info("referer:"+referer);

        if (StrUtil.isBlank(referer)) {
            throw new BizException(ResultCodeEnum.NO_PERMISSION);
        }
        //referer 截取
        String replace = referer.replace("https://", "");
        String newReferer = "https://"+replace.substring(0, replace.indexOf("/")+1);
        if (!checkReferer(newReferer)) {
            throw new BizException(ResultCodeEnum.NO_PERMISSION);
        }

        OutputStream out = null;
        try {
            String fileName = request.getParameter("fileName");
            if (StrUtil.isBlank(fileName)) {
                throw new BizException("fileName不能为空");
            }
            log.info("文件下载key:{},fileName:{}",key,fileName);
            response.setHeader("Pragma", "No-cache");
            response.setHeader("Cache-Control", "No-cache");
            response.setDateHeader("Expires", 0);
            response.setContentType("application/octet-stream");
            String agent = request.getHeader("User-Agent");
            if (null != agent && agent.contains("MSIE") || null != agent && agent.contains("Trident") || null != agent && agent.contains("Edge")) {
                // ie浏览器及Edge浏览器
               fileName = java.net.URLEncoder.encode(fileName, "UTF-8");
            } else if (null != agent && agent.contains("Mozilla")) {
                // 火狐,Chrome等浏览器
                fileName = new String(fileName.getBytes(StandardCharsets.UTF_8), StandardCharsets.ISO_8859_1);
            }else {
                // 其它浏览器
                fileName = URLEncoder.encode(fileName, "utf-8");
            }
            response.setHeader("Content-Disposition", "attachment; filename="+fileName);
            ResponseBytes<GetObjectResponse> objectBytes = S3Util.downloadFile(key,bucketName);
            InputStream inputStream = objectBytes.asInputStream();
            BufferedInputStream bufInputStream = new BufferedInputStream(inputStream);
            out = response.getOutputStream();
            byte[] buf = new byte[1024];
            int len;
            while ((len = bufInputStream.read(buf)) > 0) {
                out.write(buf, 0, len);
            }
            response.flushBuffer();
            out.close();
        } catch (IOException e) {
            log.error("文件下载失败：",e);
            throw new BizException(ResultCodeEnum.RT_ERROR);
        }catch (S3Exception e) {
            log.error("文件下载失败：",e);
            throw new BizException(e.getMessage());
        }

    }

    public void deleteFile(List<String> keys){
        if (CollUtil.isEmpty(keys)) {
            throw new BizException(ResultCodeEnum.NO_DATA);
        }
        String bucketName = SpringContextUtils.getEnvParam("aws.s3.bucketName");
        S3Util.deleteByKeys(keys,bucketName);
    }

    public void convert(HttpServletRequest request,HttpServletResponse response) {
        //从param参数中获取fileName,如果为空则取当前时间为文件名
        String fileName = request.getParameter("fileName");
        fileName = fileName==null? DateUtils.format(new Date()) : fileName;
        response.setContentType("application/pdf");
        //要保存的文件名
        response.setHeader("Content-Disposition", "inline;filename=" + fileName + ".pdf");
        response.addHeader("Pargam", "no-cache");
        response.addHeader("Cache-Control", "no-cache");

        ServletOutputStream outputStream = null;
        BufferedReader bufferReader=null;
        String base64Str="";
        try {
            if(StringUtils.isNotBlank(request.getParameter("base64Str"))){
                base64Str=request.getParameter("base64Str");
            }else {
                bufferReader = new BufferedReader(request.getReader());
                StringBuilder sb = new StringBuilder();
                String line = null;
                while ((line = bufferReader.readLine()) != null) {
                    sb.append(line);
                }
                String body = sb.toString();
                String[] strings = body.split("&");
                Map<String, String> valueMap = new HashMap<>();
                for (String string : strings) {
                    String[] keyValue = string.split("=", 2);
                    String key = keyValue[0];
                    String value = keyValue[1];
                    valueMap.put(URLDecoder.decode(key, "UTF-8"), URLDecoder.decode(value, "UTF-8"));
                }
                base64Str = valueMap.get("base64Str");
            }
            outputStream = response.getOutputStream();
            byte[] b = DatatypeConverter.parseBase64Binary(base64Str);
            outputStream.write(b, 0, b.length);
        } catch (IOException e) {
            log.error("文件转换异常：",e);
            throw new BizException(ResultCodeEnum.RT_ERROR);
        }finally {
            try {
                if(bufferReader!=null)bufferReader.close();
            } catch (IOException e) {
            }
        }
    }

    public static String getFilecharset(InputStream inputStream) {
        //默认GBK
        String charset = "GBK";
        byte[] first3Bytes = new byte[3];
        try(BufferedInputStream bis = new BufferedInputStream(inputStream)) {
            bis.mark(0);
            int read = bis.read(first3Bytes, 0, 3);
            // 文件编码为 ANSI
            if (read == -1) {
                return charset;
            }
            // 文件编码为 Unicode
            if (first3Bytes[0] == (byte) 0xFF && first3Bytes[1] == (byte) 0xFE) {
                return  "UTF-16LE";
            }
            // 文件编码为 Unicode big endian
            if (first3Bytes[0] == (byte) 0xFE && first3Bytes[1] == (byte) 0xFF) {
                return "UTF-16BE";
            }
            // 文件编码为 UTF-8
            if (first3Bytes[0] == (byte) 0xEF && first3Bytes[1] == (byte) 0xBB && first3Bytes[2] == (byte) 0xBF) {
                return "UTF-8";
            }
            bis.reset();

            int loc = 0;
            while ((read = bis.read()) != -1) {
                loc++;
                if (read >= 0xF0) {
                    break;
                }
                // 单独出现BF以下的，也算是GBK
                if (0x80 <= read && read <= 0xBF) {
                    break;
                }
                if (0xC0 <= read && read <= 0xDF) {
                    read = bis.read();
                    // 双字节 (0xC0 - 0xDF)
                    if (0x80 <= read && read <= 0xBF) {
                        // (0x80
                        // - 0xBF),也可能在GB编码内
                        continue;
                    }
                    break;
                }
                // 也有可能出错，但是几率较小
                if (0xE0 <= read && read <= 0xEF) {
                    read = bis.read();
                    if (0x80 <= read && read <= 0xBF) {
                        read = bis.read();
                        if (0x80 <= read && read <= 0xBF) {
                            charset = "UTF-8";
                        }
                    }
                    break;
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return charset;
    }
}