package com.lf.server.service.all;

import com.lf.server.controller.all.BaseController;
import com.lf.server.entity.all.ResponseMsg;
import com.lf.server.entity.sys.AttachEntity;
import com.lf.server.entity.sys.UserEntity;
import com.lf.server.helper.PathHelper;
import com.lf.server.service.sys.AttachService;
import com.sun.xml.internal.fastinfoset.tools.XML_SAX_StAX_FI;
import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.tomcat.util.http.fileupload.FileItem;
import org.apache.tomcat.util.http.fileupload.disk.DiskFileItemFactory;
import org.apache.tomcat.util.http.fileupload.servlet.ServletFileUpload;
import org.apache.tomcat.util.http.fileupload.servlet.ServletRequestContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.List;
import java.util.UUID;

/**
 * 文件服务类
 * @author WWW
 */
@Service
public class FileService {
    @Autowired
    PathHelper pathHelper;

    @Autowired
    AttachService attachService;

    private static long MAX_FILE_SIZE = 20 * 1024 * 1024;

    private final static Log log = LogFactory.getLog(FileService.class);

    public ResponseMsg<String> upload(UserEntity ue, String tab, MultipartFile file, BaseController ctrl) {
        try {
            if (file == null && file.isEmpty()) {
                return ctrl.fail("文件上传为空", null);
            }
            if (file.getSize() > MAX_FILE_SIZE) {
                return ctrl.fail(String.format("文件大于 %d MB", MAX_FILE_SIZE / 1024 / 1024), null);
            }

            // 传输文件
            String oldName = file.getOriginalFilename();
            String filePath = pathHelper.getConfig().getTempPath() + File.separator + oldName;
            File newFile = new File(filePath);
            file.transferTo(newFile);

            // 获取MD5
            String md5 = getFileMd5(filePath);
            AttachEntity entity = attachService.selectByGuid(md5);
            if (entity != null) {
                newFile.delete();
                return ctrl.success("文件已存在", md5);
            }

            String uploadPath = pathHelper.getUploadFullPath();
            String targetPath = uploadPath + File.separator + md5;
            newFile.renameTo(new File(targetPath));

            AttachEntity ae = getAttachEntity(ue, tab, oldName, md5);
            int rows = attachService.insert(ae);

            return rows > 0 ? ctrl.success(md5) : ctrl.fail("保存文件失败", null);
        } catch (Exception ex) {
            return ctrl.fail(ex.getMessage(), null);
        }
    }

    private String getFileMd5(String filePath) throws IOException {
        FileInputStream fileStream = new FileInputStream(filePath);
        String md5 = DigestUtils.md5Hex(fileStream);
        fileStream.close();

        return md5;
    }

    protected AttachEntity getAttachEntity(UserEntity ue, String tab, String oldName, String md5) {
        AttachEntity entity = new AttachEntity();
        entity.setName(oldName);
        entity.setTab(tab);
        entity.setGuid(md5);
        String subPath = PathHelper.getUploadPath() + File.separator + md5;
        entity.setPath(subPath);
        if (ue != null) {
            entity.setCreateUser(ue.getId());
        }

        return entity;
    }

    /**
     * 上传文件
     *
     * @param req
     * @param res
     */
    public void upload(HttpServletRequest req, HttpServletResponse res) {
        try {
            // 处理中文乱码问题
            req.setCharacterEncoding("utf-8");
            res.setContentType("text/html;charset=utf-8");

            // 检查请求是/否是multipart/form-data类型
            if (!ServletFileUpload.isMultipartContent(req)) {
                throw new RuntimeException("表单的enctype属性不是multipart/form-data类型！！");
            }

            // 创建上传所需要的两个对象：磁盘文件对象+文件上传对象
            DiskFileItemFactory factory = new DiskFileItemFactory();
            ServletFileUpload sfu = new ServletFileUpload(factory);
            ServletRequestContext ctx = new ServletRequestContext(req);

            //限制单个文件的大小
            sfu.setFileSizeMax(1024 * 10);

            //限制上传的总文件大小
            sfu.setSizeMax(1024 * 200);

            // 设置编码方式
            sfu.setHeaderEncoding("utf-8");

            // list容器用来保存表单中的所有数据信息
            List<FileItem> items = sfu.parseRequest(ctx);

            // 遍历容器，处理解析的内容：一个处理普通表单域，一个处理文件的表单域
            for (FileItem item : items) {
                if (item.isFormField()) {
                    handleFormField(item);
                } else {
                    handleFileField(item, req);
                }
            }
        } catch (Exception ex) {
            log.error(ex.getMessage() + ex.getStackTrace() + "\n");
        }
    }

    /**
     * 处理 普通数据项
     *
     * @param item
     */
    private void handleFormField(FileItem item) {
        // 获取 普通数据项中的 name值
        String fieldName = item.getFieldName();

        // 获取 普通数据项中的 value值
        String value = "";
        try {
            // 以 utf-8的编码格式来解析 value值
            value = item.getString("utf-8");
        } catch (Exception ex) {
            log.error(ex.getMessage() + ex.getStackTrace() + "\n");
        }

        // 输出到控制台
        System.out.println("fieldName:" + fieldName + "--value:" + value);
    }

    /**
     * 处理 文件数据项
     *
     * @param item
     */
    private void handleFileField(FileItem item, HttpServletRequest req) {
        // 获取 文件数据项中的 文件名
        String fileName = item.getName();

        // 判断 此文件的文件名是否合法
        if (fileName == null || "".equals(fileName)) {
            return;
        }

        // 控制只能上传图片
        String img = "image";
        if (!item.getContentType().startsWith(img)) {
            return;
        }

        // 将文件信息输出到控制台:文件名+文件大小
        System.out.println("fileName:" + fileName);
        System.out.println("fileSize:" + item.getSize());

        // 获取 当前项目下的 /files 目录的绝对位置
        ServletContext ctx = req.getSession().getServletContext();
        String path = ctx.getRealPath("/files");

        // 创建 file对象
        File file = new File(path);
        if (!file.exists()) {
            // 创建目录
            file.mkdir();
        }

        // 将文件保存到服务器上（UUID是通用唯一标识码）
        try {
            item.write(new File(file.toString(), UUID.randomUUID() + "_" + fileName));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}