package edu.whut.smilepicturebackend.service.impl;
import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.ObjUtil;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import edu.whut.smilepicturebackend.annotation.AuthCheck;
import edu.whut.smilepicturebackend.common.BaseResponse;
import edu.whut.smilepicturebackend.common.ResultUtils;
import edu.whut.smilepicturebackend.constant.UserConstant;
import edu.whut.smilepicturebackend.exception.BusinessException;
import edu.whut.smilepicturebackend.exception.ErrorCode;
import edu.whut.smilepicturebackend.exception.ThrowUtils;
import edu.whut.smilepicturebackend.manager.auth.StpKit;
import edu.whut.smilepicturebackend.model.dto.user.UserAddRequest;
import edu.whut.smilepicturebackend.model.dto.user.UserQueryRequest;
import edu.whut.smilepicturebackend.model.entity.User;
import edu.whut.smilepicturebackend.model.enums.UserRoleEnum;
import edu.whut.smilepicturebackend.model.vo.LoginUserVO;
import edu.whut.smilepicturebackend.model.vo.UserVO;
import edu.whut.smilepicturebackend.service.UserService;
import edu.whut.smilepicturebackend.mapper.UserMapper;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.GetMapping;

import javax.servlet.http.HttpServletRequest;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;


/**
* @author 张三
* @description 针对表【user(用户)】的数据库操作Service实现
*/
@Service
@Slf4j
@RequiredArgsConstructor
public class UserServiceImpl extends ServiceImpl<UserMapper, User>
    implements UserService{
    private final BCryptPasswordEncoder passwordEncoder;
    /**
     * 用户注册
     *
     * @param userAccount   用户账户
     * @param userPassword  用户密码
     * @param checkPassword 校验密码
     * @return
     */
    @Override
    public long userRegister(String userAccount, String userPassword, String checkPassword) {
        // 1. 校验参数
        if (StrUtil.hasBlank(userAccount, userPassword, checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户账号过短");
        }
        if (userPassword.length() < 8 || checkPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户密码过短");
        }
        if (!userPassword.equals(checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "两次输入的密码不一致");
        }
        // 2. 检查用户账号是否和数据库中已有的重复
        LambdaQueryWrapper<User> lambda = Wrappers.lambdaQuery();
        lambda.eq(User::getUserAccount, userAccount);
        long count = this.baseMapper.selectCount(lambda);
        if (count > 0) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号重复");
        }
        // 3. 密码一定要加密
        String encryptPassword = getEncryptPassword(userPassword);
        // 4. 插入数据到数据库中
        User user = new User();
        user.setUserAccount(userAccount);
        user.setUserPassword(encryptPassword);
        user.setUserName("无名");
        user.setUserRole(UserRoleEnum.USER.getValue());
        boolean saveResult = this.save(user);
        if (!saveResult) {
            throw new BusinessException(ErrorCode.SYSTEM_ERROR, "注册失败，数据库错误");
        }
        return user.getId();
    }
    /**
     * 获取加密后的密码
     *
     * @param userPassword 用户密码
     * @return 加密后的密码
     */
    @Override
    public String getEncryptPassword(String userPassword) {
        return passwordEncoder.encode(userPassword);
//        // 加盐，混淆密码
//        final String SALT = "smile12306";
//        return DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes());
    }

    @Override
    public LoginUserVO userLogin(String userAccount, String userPassword, HttpServletRequest request) {
        // 1. 校验
        if (StrUtil.hasBlank(userAccount, userPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户账号错误");
        }
        if (userPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户密码错误");
        }
        // 2. 根据账号查询用户（不带密码）
        LambdaQueryWrapper<User> lambda = Wrappers.lambdaQuery();
        lambda.eq(User::getUserAccount, userAccount);
        User user = this.baseMapper.selectOne(lambda);
        if (user == null) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户不存在或者密码错误");
        }
        // 3. 用 BCryptPasswordEncoder 去校验明文密码 vs 数据库里存的加密密码
        if (!passwordEncoder.matches(userPassword, user.getUserPassword())) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户不存在或者密码错误");
        }
        // 4. 保存用户的登录态
        request.getSession().setAttribute(UserConstant.USER_LOGIN_STATE, user);
        // 记录用户登录态到 Sa-token，便于空间鉴权时使用，注意保证该用户信息与 SpringSession 中的信息过期时间一致
        StpKit.SPACE.login(user.getId());
        StpKit.SPACE.getSession().set(UserConstant.USER_LOGIN_STATE, user);
        return this.getLoginUserVO(user);
    }

    /**
     * 获取脱敏后的用户信息（无密码）
     *
     * @param user 用户
     * @return 脱敏后的用户信息
     */
    @Override
    public LoginUserVO getLoginUserVO(User user) {
        if (user == null) {
            return null;
        }
        LoginUserVO loginUserVO = new LoginUserVO();
        BeanUtil.copyProperties(user, loginUserVO);
        return loginUserVO;
    }

    /**
     * 获得脱敏后的用户信息（无密码、更新、编辑时间）
     *
     * @param user
     * @return
     */
    @Override
    public UserVO getUserVO(User user) {
        if (user == null) {
            return null;
        }
        UserVO userVO = new UserVO();
        BeanUtil.copyProperties(user, userVO);
        return userVO;
    }

    /**
     * 获取脱敏后的用户列表
     *
     * @param userList
     * @return
     */
    @Override
    public List<UserVO> getUserVOList(List<User> userList) {
        if (CollUtil.isEmpty(userList)) {
            return new ArrayList<>();
        }
        return userList.stream()
                .map(this::getUserVO)
                .collect(Collectors.toList());
    }

    /**
     * 获取当前登录用户
     * @param request
     * @return
     */
    @Override
    public User getLoginUser(HttpServletRequest request) {
        // 判断是否已经登录
        Object userObj = request.getSession().getAttribute(UserConstant.USER_LOGIN_STATE);
        User currentUser = (User) userObj;
        if (currentUser == null || currentUser.getId() == null) {
            throw new BusinessException(ErrorCode.NOT_LOGIN_ERROR);
        }
//        // 从数据库中查询（追求性能的话可以注释，直接返回上述结果）
//        Long userId = currentUser.getId();
//        currentUser = this.getById(userId);
//        if (currentUser == null) {
//            throw new BusinessException(ErrorCode.NOT_LOGIN_ERROR);
//        }
        return currentUser;
    }

    /**
     * 退出登录
     *
     * @param request
     * @return
     */
    @Override
    public boolean userLogout(HttpServletRequest request) {
        // 判断是否已经登录
        Object userObj = request.getSession().getAttribute(UserConstant.USER_LOGIN_STATE);
        if (userObj == null) {
            throw new BusinessException(ErrorCode.OPERATION_ERROR, "未登录");
        }
        // 移除登录态
        request.getSession().removeAttribute(UserConstant.USER_LOGIN_STATE);
        return true;
    }

    /**
     * 查询条件
     * @param req
     * @return
     */
    @Override
    public LambdaQueryWrapper<User> getQueryWrapper(UserQueryRequest req) {
        if (req == null) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "请求参数为空");
        }

        LambdaQueryWrapper<User> qw = Wrappers.lambdaQuery(User.class);

        // 基本等值和模糊匹配
        qw.eq(ObjUtil.isNotNull(req.getId()), User::getId, req.getId())
                .eq(StrUtil.isNotBlank(req.getUserRole()), User::getUserRole, req.getUserRole())
                .like(StrUtil.isNotBlank(req.getUserAccount()), User::getUserAccount, req.getUserAccount())
                .like(StrUtil.isNotBlank(req.getUserName()),    User::getUserName,    req.getUserName())
                .like(StrUtil.isNotBlank(req.getUserProfile()), User::getUserProfile, req.getUserProfile());

        // 动态排序
        if (StrUtil.isNotBlank(req.getSortField())) {
            String column = StrUtil.toUnderlineCase(req.getSortField());
            boolean asc = "ascend".equalsIgnoreCase(req.getSortOrder());
            qw.last("ORDER BY " + column + (asc ? " ASC" : " DESC"));
        }

        return qw;
    }

    @Override
    public boolean isAdmin(User user) {
        return user != null && UserRoleEnum.ADMIN.getValue().equals(user.getUserRole());
    }

    /**
     * 创建用户
     */
    @Override
    public long createUser(UserAddRequest req) {
        // 1. DTO -> entity
        User user = new User();
        BeanUtil.copyProperties(req, user);

        // 2. 设定默认密码并加密
        String encoded = passwordEncoder.encode(UserConstant.USER_DEFAULT);
        user.setUserPassword(encoded);

        // 3.插入数据库
        boolean result = this.save(user);
        ThrowUtils.throwIf(!result, ErrorCode.OPERATION_ERROR);
        return user.getId();
    }

}




