package com.xiaopeng.account.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.xiaopeng.account.constant.I18nKeyConstant;
import com.xiaopeng.account.mapper.SysGroupMapper;
import com.xiaopeng.account.model.dto.SysGroupAddDTO;
import com.xiaopeng.account.model.dto.SysGroupEditDTO;
import com.xiaopeng.account.model.query.GroupUserPageQuery;
import com.xiaopeng.account.model.query.SysGroupPageQuery;
import com.xiaopeng.account.model.vo.GroupUserVO;
import com.xiaopeng.account.model.vo.SysGroupDetailVO;
import com.xiaopeng.account.model.vo.SysGroupPageVO;
import com.xiaopeng.account.model.vo.SysMenuVO;
import com.xiaopeng.account.service.ISysGroupMenuService;
import com.xiaopeng.account.service.ISysGroupService;
import com.xiaopeng.api.feignClient.operation.SysMenuClient;
import com.xiaopeng.api.model.account.SysGroup;
import com.xiaopeng.api.model.operation.SysMenu;
import com.xiaopeng.common.core.domain.R;
import com.xiaopeng.common.core.exception.ServiceException;
import com.xiaopeng.common.core.utils.StringUtils;
import com.xiaopeng.common.core.web.page.PageInfo;
import com.xiaopeng.common.security.utils.SecurityUtils;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.util.*;
import java.util.stream.Collectors;

/**
 * <p>
 * 权限组设置 服务实现类
 * </p>
 *
 * @author mitao
 * @since 2026-02-03
 */
@Slf4j
@Service
@RequiredArgsConstructor(onConstructor_ = @Lazy)
public class SysGroupServiceImpl extends ServiceImpl<SysGroupMapper, SysGroup> implements ISysGroupService {

    private final ISysGroupMenuService groupMenuService;

    private final SysMenuClient sysMenuClient;

    /**
     * 新增权限组
     *
     * @param dto 新增权限组请求
     */
    @Override
    @Transactional(rollbackFor = Exception.class)
    public void addGroup(SysGroupAddDTO dto) {
        // 校验组名唯一性
        if (!checkGroupNameUnique(dto.getGroupName(), null)) {
            throw new ServiceException("权限组名称已存在", I18nKeyConstant.GROUP_NAME_EXISTS);
        }

        // 创建权限组实体
        SysGroup group = BeanUtil.copyProperties(dto, SysGroup.class);
        group.setCreateBy(SecurityUtils.getLoginUser().getSysUser().getNickName());
        // 保存权限组
        this.save(group);

        // 保存菜单关联
        groupMenuService.saveGroupMenus(group.getId(), dto.getMenuIds());
    }

    /**
     * 编辑权限组
     *
     * @param dto 编辑权限组请求
     */
    @Override
    @Transactional(rollbackFor = Exception.class)
    public void editGroup(SysGroupEditDTO dto) {
        // 校验权限组是否存在
        SysGroup existGroup = this.getById(dto.getId());
        if (existGroup == null) {
            throw new ServiceException("权限组不存在", I18nKeyConstant.GROUP_NOT_EXISTS);
        }

        // 校验组名唯一性（排除自身）
        if (!checkGroupNameUnique(dto.getGroupName(), dto.getId())) {
            throw new ServiceException("权限组名称已存在", I18nKeyConstant.GROUP_NAME_EXISTS);
        }

        // 更新权限组信息
        existGroup.setGroupName(dto.getGroupName());
        existGroup.setRemarks(dto.getRemarks());
        existGroup.setGroupType(dto.getGroupType());
        existGroup.setUpdateBy(SecurityUtils.getLoginUser().getSysUser().getNickName());
        this.updateById(existGroup);

        // 删除旧的菜单关联
        groupMenuService.deleteByGroupId(dto.getId());

        // 保存新的菜单关联
        groupMenuService.saveGroupMenus(dto.getId(), dto.getMenuIds());
    }

    /**
     * 获取权限组详情（含菜单树）
     *
     * @param id 权限组ID
     * @return 权限组详情
     */
    @Override
    public SysGroupDetailVO getGroupDetail(Long id) {
        // 查询权限组基础信息
        SysGroup group = this.getById(id);
        if (group == null) {
            throw new ServiceException("权限组不存在", I18nKeyConstant.GROUP_NOT_EXISTS);
        }

        SysGroupDetailVO vo = BeanUtil.toBean(group, SysGroupDetailVO.class);

        // 根据权限组ID获取菜单ID列表
        List<Long> menuIds = groupMenuService.selectMenuIdsByGroupId(id);
        if (CollectionUtils.isEmpty(menuIds)) {
            vo.setMenus(new ArrayList<>());
            return vo;
        }

        // 通过Feign调用获取菜单详情
        try {
            R<List<SysMenu>> result = sysMenuClient.getMenusByMenuIds(menuIds);
            if (result != null && result.getData() != null) {
                List<SysMenu> menus = result.getData();
                // 构建菜单树
                vo.setMenus(buildMenuTree(menus));
                vo.setMenuIds(menus.stream().map(SysMenu::getId).collect(Collectors.toList()));
            } else {
                vo.setMenus(new ArrayList<>());
                vo.setMenuIds(new ArrayList<>());
            }
        } catch (Exception e) {
            log.error("获取菜单列表失败: {}", e.getMessage());
            vo.setMenus(new ArrayList<>());
        }

        return vo;
    }

    /**
     * 权限组分页列表
     *
     * @param query 分页查询参数
     * @return 分页结果
     */
    @Override
    public PageInfo<SysGroupPageVO> pageList(SysGroupPageQuery query) {
        // 构建查询条件
        LambdaQueryWrapper<SysGroup> wrapper = new LambdaQueryWrapper<>();
        if (StringUtils.isNotBlank(query.getGroupName())) {
            wrapper.like(SysGroup::getGroupName, query.getGroupName());
        }
        wrapper.orderByDesc(SysGroup::getCreateTime);

        // 分页查询
        PageInfo<SysGroup> pageInfo = new PageInfo<>(query.getPageNum(), query.getPageSize());
        PageInfo<SysGroup> groupPage = this.page(pageInfo, wrapper);

        // 转换为VO
        PageInfo<SysGroupPageVO> resultPage = new PageInfo<>(query.getPageNum(), query.getPageSize());
        resultPage.setTotal(groupPage.getTotal());

        List<SysGroupPageVO> voList = groupPage.getRecords().stream().map(group -> {
            SysGroupPageVO vo = BeanUtil.copyProperties(group, SysGroupPageVO.class);
            // 统计绑定用户数
            Long bindCount = baseMapper.countBindUsers(group.getId());
            vo.setBindCount(bindCount != null ? bindCount : 0L);
            return vo;
        }).collect(Collectors.toList());

        resultPage.setRecords(voList);
        return resultPage;
    }

    /**
     * 查询权限组绑定用户分页列表
     *
     * @param query 分页查询参数
     * @return 分页结果
     */
    @Override
    public PageInfo<GroupUserVO> queryUserPageList(GroupUserPageQuery query) {
        // 校验权限组是否存在
        SysGroup group = this.getById(query.getGroupId());
        if (group == null) {
            throw new ServiceException("权限组不存在");
        }

        // 分页查询
        PageInfo<GroupUserVO> pageInfo = new PageInfo<>(query.getPageNum(), query.getPageSize());
        query.setGroupType(group.getGroupType());
        List<GroupUserVO> records = baseMapper.queryUserPageList(query);

        // 手动设置分页信息（因为使用了自定义SQL）
        pageInfo.setRecords(records);
        pageInfo.setTotal((long) records.size());

        return pageInfo;
    }

    /**
     * 校验权限组名称唯一性
     *
     * @param groupName 权限组名称
     * @param excludeId 排除的权限组ID（编辑时使用）
     * @return true=唯一，false=不唯一
     */
    @Override
    public boolean checkGroupNameUnique(String groupName, Long excludeId) {
        LambdaQueryWrapper<SysGroup> wrapper = new LambdaQueryWrapper<>();
        wrapper.eq(SysGroup::getGroupName, groupName);
        if (excludeId != null) {
            wrapper.ne(SysGroup::getId, excludeId);
        }
        return this.count(wrapper) == 0;
    }

    /**
     * 构建菜单树
     *
     * @param menus 菜单列表
     * @return 菜单树
     */
    private List<SysMenuVO> buildMenuTree(List<SysMenu> menus) {
        if (CollectionUtils.isEmpty(menus)) {
            return new ArrayList<>();
        }

        Map<Long, SysMenuVO> menuMap = new HashMap<>();
        List<SysMenuVO> rootMenus = new ArrayList<>();

        // 转换为VO并建立映射
        for (SysMenu menu : menus) {
            SysMenuVO vo = convertToMenuVO(menu);
            vo.setChildren(new ArrayList<>());
            menuMap.put(vo.getId(), vo);
        }

        // 构建树结构
        for (SysMenuVO vo : menuMap.values()) {
            if (vo.getParentId() == null || vo.getParentId() == 0) {
                rootMenus.add(vo);
            } else {
                SysMenuVO parent = menuMap.get(vo.getParentId());
                if (parent != null) {
                    parent.getChildren().add(vo);
                } else {
                    // 父节点不在列表中，作为根节点处理
                    rootMenus.add(vo);
                }
            }
        }

        // 按orderNum排序
        sortMenuTree(rootMenus);

        return rootMenus;
    }

    /**
     * 转换为菜单VO
     *
     * @param menu 菜单实体
     * @return 菜单VO
     */
    private SysMenuVO convertToMenuVO(SysMenu menu) {
        SysMenuVO vo = new SysMenuVO();
        BeanUtils.copyProperties(menu, vo);
        return vo;
    }

    /**
     * 递归排序菜单树
     *
     * @param menus 菜单列表
     */
    private void sortMenuTree(List<SysMenuVO> menus) {
        if (CollectionUtils.isEmpty(menus)) {
            return;
        }
        menus.sort(Comparator.comparing(SysMenuVO::getOrderNum, Comparator.nullsLast(Comparator.naturalOrder())));
        for (SysMenuVO menu : menus) {
            if (!CollectionUtils.isEmpty(menu.getChildren())) {
                sortMenuTree(menu.getChildren());
            }
        }
    }
}