package cn.com.goldenwater.dcproj.utils.impexcel;

import cn.com.goldenwater.dcproj.model.GwComFile;
import cn.com.goldenwater.id.util.UuidUtil;
import org.apache.commons.io.FileUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.web.multipart.MultipartFile;

import java.io.*;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

/**
 * Created by jinshui on 2019/11/1.
 */
public class FileUtil {

    private FileUtil() {
    }

    private final static String PDF = "pdf";
    private final static String DOC = "doc";
    private final static String DOCX = "docX";
    private final static String HTML = "html";
    //压缩包列表
    private final static String[] CP = {"zip", "rar"};

    /**
     * 根据上传文件 得到文件列表
     *
     * @param file
     * @return
     */
    public static List<GwComFile> getFileList(MultipartFile file, String prefix, String fileDir) throws Exception {
        List<GwComFile> list = new ArrayList<>();
        //获取 文件名.格式
        String originalFilename = file.getOriginalFilename();
        String ext = originalFilename.substring(originalFilename.lastIndexOf(".") + 1);
        if (StringUtils.isBlank(ext)) {
            return new ArrayList<>();
        }
        Calendar dat = Calendar.getInstance();
        String yearPath = dat.get(Calendar.YEAR) + File.separator + (dat.get(Calendar.MONTH) + 1) + File.separator + dat.get(Calendar.DAY_OF_MONTH);
        fileDir = fileDir + yearPath;
        prefix = prefix + yearPath;
        int index = isZip(ext);
        //是否是压缩包
        if (index < 0) {
            //单个文件
            GwComFile gwComFile = getGwComFile(file.getName(), (double) file.getSize(), prefix);
            FileUtils.copyInputStreamToFile(file.getInputStream(), new File(fileDir, gwComFile.getId() + "." + gwComFile.getFileExt()));
            list.add(gwComFile);
            return list;
        }
        switch (index) {
            case 0:
                list.addAll(dealZipFile(file, prefix, fileDir));
                break;
            case 1:
                break;
            case 2:
                break;
            case 3:
                break;
        }
        return list;
    }


    private static List<GwComFile> dealZipFile(MultipartFile file, String prefix, String fileDir) throws IOException {
        List<GwComFile> list = new ArrayList<>();
        ZipInputStream zpIs = new ZipInputStream(file.getInputStream(), Charset.forName(getFilecharset(file)));
        ZipEntry ze = null;
        String path = fileDir;
        File pathFile = new File(path);
        if (!pathFile.exists()) {
            pathFile.mkdirs();
        }
        while ((ze = zpIs.getNextEntry()) != null) {
            if (ze.isDirectory() || ze.getName().endsWith("/")) {
                //暂时不处理压缩包里有文件夹这种形式
                continue;
            }
            GwComFile gwComFile = getGwComFile(ze.getName(), (double) ze.getSize(), prefix);

            ByteArrayOutputStream byteArrayOutputStream=new ByteArrayOutputStream();
            byte[] byte_s=new byte[1024];
            int num=-1;
            while((num=zpIs.read(byte_s,0,byte_s.length))>-1) {//通过read方法来读取文件内容
                byteArrayOutputStream.write(byte_s, 0, num);
            }
            File outFile = new File(fileDir, gwComFile.getId() + "." + gwComFile.getFileExt());
            FileOutputStream fileOutputStream = new FileOutputStream(outFile);
            fileOutputStream.write(byteArrayOutputStream.toByteArray());
            list.add(gwComFile);
            byteArrayOutputStream.close();
            fileOutputStream.close();
        }
        zpIs.close();
        return list;
    }

    private static int isZip(String ext) {
        for (int i = 0; i < CP.length; i++) {
            if (CP[i].equalsIgnoreCase(ext)) {
                return i;
            }
        }
        return -1;
    }

    public static GwComFile getGwComFile(String fileName, double size, String prefix) throws IOException {
        GwComFile gwComFile = new GwComFile();
        gwComFile.setId(UuidUtil.uuid());
        gwComFile.setCreateDate(Calendar.getInstance().getTime());
        gwComFile.setFileTitle(fileName);
        gwComFile.setFileName(fileName);
        gwComFile.setFileSize(size);
        gwComFile.setFileExt(fileName.substring(1 + fileName.lastIndexOf(".")));
        String filePath = prefix + File.separator + gwComFile.getId() + "." + gwComFile.getFileExt();
        gwComFile.setFilePath(filePath);
        return gwComFile;
    }

    //判断编码格式方法
    public static String getFilecharset(MultipartFile file) {
        String charset = "GBK";
        byte[] first3Bytes = new byte[3];
        try {
            boolean checked = false;
            BufferedInputStream bis = new BufferedInputStream(file.getInputStream());
            bis.mark(0);
            int read = bis.read(first3Bytes, 0, 3);
            if (read == -1) {
                return charset; //文件编码为 ANSI
            } else if (first3Bytes[0] == (byte) 0xFF
                    && first3Bytes[1] == (byte) 0xFE) {
                charset = "UTF-16LE"; //文件编码为 Unicode
                checked = true;
            } else if (first3Bytes[0] == (byte) 0xFE
                    && first3Bytes[1] == (byte) 0xFF) {
                charset = "UTF-16BE"; //文件编码为 Unicode big endian
                checked = true;
            } else if (first3Bytes[0] == (byte) 0xEF
                    && first3Bytes[1] == (byte) 0xBB
                    && first3Bytes[2] == (byte) 0xBF) {
                charset = "UTF-8"; //文件编码为 UTF-8
                checked = true;
            }
            bis.reset();
            if (!checked) {
                int loc = 0;
                while ((read = bis.read()) != -1) {
                    loc++;
                    if (read >= 0xF0) {
                        break;
                    }
                    if (0x80 <= read && read <= 0xBF) // 单独出现BF以下的，也算是GBK
                    {
                        break;
                    }
                    if (0xC0 <= read && read <= 0xDF) {
                        read = bis.read();
                        if (0x80 <= read && read <= 0xBF) // 双字节 (0xC0 - 0xDF)
                        {
                            continue;
                        } else {
                            break;
                        }
                    } else if (0xE0 <= read && read <= 0xEF) {// 也有可能出错，但是几率较小
                        read = bis.read();
                        if (0x80 <= read && read <= 0xBF) {
                            read = bis.read();
                            if (0x80 <= read && read <= 0xBF) {
                                charset = "UTF-8";
                                break;
                            } else {
                                break;
                            }
                        } else {
                            break;
                        }
                    }
                }
            }
            bis.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return charset;
    }
}