package com.terra.system.service.all;

import com.terra.system.entity.ctrl.FileInfoEntity;
import com.terra.system.helper.PathHelper;
import com.terra.system.helper.StringHelper;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.fileupload.servlet.ServletRequestContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.annotation.Resource;
import org.springframework.stereotype.Service;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * CommonsFileupload上传服务
 * @author WWW
 */
@Service
public class CommonsFileuploadService {
    @Resource
    PathHelper pathHelper;

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

    public Object fileUpload(HttpServletRequest req, HttpServletResponse res) throws Exception {
        List<FileItem> items = getFileItem(req, res);

        return copeFileItems(items, req);
    }

    /**
     * 获取文件项
     */
    private List<FileItem> getFileItem(HttpServletRequest req, HttpServletResponse res) throws Exception {
        // 处理中文乱码问题
        req.setCharacterEncoding("utf-8");
        // text/html;charset=utf-8
        res.setContentType("application/json;charset=utf-8");

        // 检查请求是/否为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);

        // 设置编码方式
        sfu.setHeaderEncoding("utf-8");
        factory.setSizeThreshold(4096);

        // 获取表单中的所有数据信息
        List<FileItem> list = sfu.parseRequest(ctx);

        return list;
    }

    /**
     * 处理解析内容：处理普通表单域和文件表单域
     */
    private Object copeFileItems(List<FileItem> items, HttpServletRequest req) throws Exception {
        Map<String, String> map = new HashMap<String, String>(3);
        List<FileInfoEntity> list = new ArrayList<FileInfoEntity>();

        String path = pathHelper.getTempPath();
        for (FileItem item : items) {
            if (item.isFormField()) {
                String key = item.getFieldName();
                String value = item.getString("utf-8");
                map.put(key, value);
                continue;
            }

            FileInfoEntity fi = copeFile(item, path, req);
            if (fi != null) {
                list.add(fi);
            }
        }

        return map;
    }

    /**
     * 处理文件
     */
    private FileInfoEntity copeFile(FileItem item, String path, HttpServletRequest req) {
        try {
            // 获取文件名，判断是否合法
            FileInfoEntity fi = new FileInfoEntity(item.getName());
            if (StringHelper.isEmpty(fi.getFileName())) {
                return null;
            }

            fi.setSize(item.getSize());
            fi.setPath(path + File.separator + fi.getFileName());
            item.write(new File(fi.getPath()));

            return fi;
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
            return null;
        }
    }
}