package com.example.service.impl;

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.read.listener.ReadListener;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.example.entity.User;
import com.example.excel.UserImportExcel;
import com.example.mapper.UserMapper;
import com.example.service.UserService;
import com.example.utils.Md5Util;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {

    @Override
    public IPage<User> getUserPage(Long current, Long size, String username, String realName, String deptCode, List<String> permissionDeptCodes) {
        Page<User> page = new Page<>(current, size);
        page.setOptimizeJoinOfCountSql(false);
        page.setOptimizeCountSql(false);
        LambdaQueryWrapper<User> wrapper = new LambdaQueryWrapper<>();
        wrapper.like(username != null && !username.isEmpty(), User::getUsername, username)
                .like(realName != null && !realName.isEmpty(), User::getRealName, realName)
                .eq(deptCode != null && !deptCode.isEmpty(), User::getDeptCode, deptCode)
                .in(permissionDeptCodes != null && !permissionDeptCodes.isEmpty(), User::getDeptCode, permissionDeptCodes)
                .orderByDesc(User::getId);
        return page(page, wrapper);
    }

    @Override
    public User getUserWithDeptById(Long id) {
        return baseMapper.selectUserWithDeptById(id);
    }

    @Override
    public boolean checkUsernameExists(String username) {
        return lambdaQuery().eq(User::getUsername, username).one() != null;
    }

    @Override
    public String importUsers(MultipartFile file, List<String> permissionDeptCodes) {
        List<User> userList = new ArrayList<>();
        List<String> errorMsgs = new ArrayList<>();

        try {
            EasyExcel.read(file.getInputStream(), UserImportExcel.class, new ReadListener<UserImportExcel>() {
                @Override
                public void invoke(UserImportExcel data, AnalysisContext context) {
                    if (checkUsernameExists(data.getUsername())) {
                        errorMsgs.add("用户名已存在: " + data.getUsername());
                        return;
                    }
                    if (!permissionDeptCodes.contains(data.getDeptCode())) {
                        errorMsgs.add("无权限导入部门: " + data.getDeptCode() + ", 用户名: " + data.getUsername());
                        return;
                    }
                    User user = new User();
                    user.setUsername(data.getUsername());
                    user.setRealName(data.getRealName());
                    user.setPassword(Md5Util.encrypt("123456"));
                    if(data.getEmail() != null && !data.getEmail().isEmpty()){
                        user.setEmail(data.getEmail());
                    }
                    if(data.getPhone() != null && !data.getPhone().isEmpty()){
                        user.setPhone(data.getPhone());
                    }
                    user.setDeptCode(data.getDeptCode());
                    user.setStatus(1);
                    userList.add(user);
                }

                @Override
                public void doAfterAllAnalysed(AnalysisContext context) {
                }
            }).sheet().doRead();
        } catch (IOException e) {
            return "导入失败: " + e.getMessage();
        }

        if (!errorMsgs.isEmpty()) {
            return "导入部分失败: " + String.join(", ", errorMsgs);
        }

        if (saveBatch(userList)) {
            return "成功导入 " + userList.size() + " 条记录";
        } else {
            return "导入失败";
        }
    }

    @Override
    public List<User> getUsersByDeptCode(String deptCode) {
        return baseMapper.selectByDeptCode(deptCode);
    }

    @Override
    public boolean changePassword(Long userId, String oldPassword, String newPassword) {
        User user = getById(userId);
        if (user == null) {
            return false;
        }
        if (!user.getPassword().equals(Md5Util.encrypt(oldPassword))) {
            return false;
        }
        user.setPassword(Md5Util.encrypt(newPassword));
        return updateById(user);
    }
}