package com.sinata.appointment.service;

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.sinata.appointment.constants.CacheNames;
import com.sinata.appointment.constants.BizErrorCode;
import com.sinata.appointment.dto.PassAreaCreateRequest;
import com.sinata.appointment.dto.PassAreaDetailVo;
import com.sinata.appointment.dto.PassAreaListVo;
import com.sinata.appointment.dto.PassAreaUpdateRequest;
import com.sinata.appointment.entity.MpPassAccessArea;
import com.sinata.appointment.exception.BizException;
import com.sinata.appointment.mapper.MpPassAccessAreaMapper;
import com.sinata.appointment.util.UuidAssert;
import java.util.Map;
import org.springframework.cache.Cache;
import org.springframework.cache.CacheManager;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.StringUtils;

@Service
public class PassAreaManageApplicationService {

    private final MpPassAccessAreaMapper mpPassAccessAreaMapper;
    private final CacheManager cacheManager;

    public PassAreaManageApplicationService(
            MpPassAccessAreaMapper mpPassAccessAreaMapper, CacheManager cacheManager) {
        this.mpPassAccessAreaMapper = mpPassAccessAreaMapper;
        this.cacheManager = cacheManager;
    }

    public IPage<PassAreaListVo> page(long page, long size, Long pid, String areaName) {
        long p = pid == null ? 0L : pid;
        LambdaQueryWrapper<MpPassAccessArea> q =
                new LambdaQueryWrapper<MpPassAccessArea>()
                        .eq(MpPassAccessArea::getDelFlag, 0)
                        .eq(MpPassAccessArea::getPid, p)
                        .like(StringUtils.hasText(areaName), MpPassAccessArea::getAreaName, trim(areaName))
                        .orderByDesc(MpPassAccessArea::getCreateTime);
        Page<MpPassAccessArea> pg = mpPassAccessAreaMapper.selectPage(new Page<>(page, size), q);
        return pg.convert(this::toListVo);
    }

    public PassAreaDetailVo detail(Long id, String uuid) {
        MpPassAccessArea e = loadActive(id, uuid);
        PassAreaDetailVo vo = new PassAreaDetailVo();
        vo.setId(e.getId());
        vo.setUuid(e.getUuid());
        vo.setPid(e.getPid());
        vo.setAreaName(e.getAreaName());
        vo.setRemark(e.getRemark());
        vo.setAreaDesc(e.getAreaDesc());
        if (e.getPid() != null && e.getPid() > 0) {
            MpPassAccessArea parent = mpPassAccessAreaMapper.selectById(e.getPid());
            if (parent != null
                    && (parent.getDelFlag() == null || parent.getDelFlag() == 0)
                    && StringUtils.hasText(parent.getAreaName())) {
                vo.setParentAreaName(parent.getAreaName());
            }
        }
        return vo;
    }

    @Transactional(rollbackFor = Exception.class)
    public Map<String, Object> create(PassAreaCreateRequest req) {
        long pid = req.getPid() == null ? 0L : req.getPid();
        validateParentPid(pid);
        String name = req.getAreaName().trim();
        assertNameUniqueUnderPid(pid, name, null);
        MpPassAccessArea e = new MpPassAccessArea();
        e.setPid(pid);
        e.setAreaName(name);
        e.setRemark(trimToNull(req.getRemark()));
        e.setAreaDesc(trimToNull(req.getAreaDesc()));
        mpPassAccessAreaMapper.insert(e);
        MpPassAccessArea fresh = mpPassAccessAreaMapper.selectById(e.getId());
        if (fresh == null || !StringUtils.hasText(fresh.getUuid())) {
            throw new BizException(BizErrorCode.AUTH_FORBIDDEN, "创建后读取失败");
        }
        evictMiniPassAccessAreaTreeCache();
        return Map.of("id", fresh.getId(), "uuid", fresh.getUuid());
    }

    @Transactional(rollbackFor = Exception.class)
    public void update(Long id, PassAreaUpdateRequest req) {
        MpPassAccessArea e = loadActive(id, req.getUuid());
        String name = req.getAreaName().trim();
        long targetPid;
        if (e.getPid() == null || e.getPid() == 0) {
            targetPid = 0L;
        } else {
            targetPid = req.getPid() != null ? req.getPid() : e.getPid();
            validateParentPid(targetPid);
        }
        assertNameUniqueUnderPid(targetPid, name, id);
        e.setPid(targetPid);
        e.setAreaName(name);
        if (req.getRemark() != null) {
            e.setRemark(trimToNull(req.getRemark()));
        }
        e.setAreaDesc(trimToNull(req.getAreaDesc()));
        mpPassAccessAreaMapper.updateById(e);
        evictMiniPassAccessAreaTreeCache();
    }

    @Transactional(rollbackFor = Exception.class)
    public void delete(Long id, String uuid) {
        MpPassAccessArea e = loadActive(id, uuid);
        long child =
                mpPassAccessAreaMapper.selectCount(
                        new LambdaQueryWrapper<MpPassAccessArea>()
                                .eq(MpPassAccessArea::getDelFlag, 0)
                                .eq(MpPassAccessArea::getPid, e.getId()));
        if (child > 0) {
            throw new BizException(BizErrorCode.DEPT_HAS_CHILDREN, "请先删除子区域");
        }
        int affected = mpPassAccessAreaMapper.deleteById(e.getId());
        if (affected <= 0) {
            throw new BizException(BizErrorCode.RESOURCE_VERIFY_FAILED, "删除失败，请刷新后重试");
        }
        evictMiniPassAccessAreaTreeCache();
    }

    private void evictMiniPassAccessAreaTreeCache() {
        Cache cache = cacheManager.getCache(CacheNames.MINI_LOOKUP);
        if (cache != null) {
            cache.evict(CacheNames.MINI_LOOKUP_PASS_ACCESS_AREA_TREE_KEY);
        }
    }

    private void validateParentPid(long pid) {
        if (pid == 0) {
            return;
        }
        MpPassAccessArea parent = mpPassAccessAreaMapper.selectById(pid);
        if (parent == null || (parent.getDelFlag() != null && parent.getDelFlag() == 1)) {
            throw new BizException(BizErrorCode.RESOURCE_VERIFY_FAILED, "上级区域不存在");
        }
        if (parent.getPid() == null || parent.getPid() != 0) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, "仅允许两级：上级须为一级区域");
        }
    }

    private void assertNameUniqueUnderPid(long pid, String name, Long excludeId) {
        LambdaQueryWrapper<MpPassAccessArea> w =
                new LambdaQueryWrapper<MpPassAccessArea>()
                        .eq(MpPassAccessArea::getDelFlag, 0)
                        .eq(MpPassAccessArea::getPid, pid)
                        .eq(MpPassAccessArea::getAreaName, name);
        if (excludeId != null) {
            w.ne(MpPassAccessArea::getId, excludeId);
        }
        if (mpPassAccessAreaMapper.selectCount(w) > 0) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, "同级下区域名称已存在");
        }
    }

    private MpPassAccessArea loadActive(Long id, String uuid) {
        MpPassAccessArea e = mpPassAccessAreaMapper.selectById(id);
        if (e == null || (e.getDelFlag() != null && e.getDelFlag() == 1)) {
            throw new BizException(BizErrorCode.RESOURCE_VERIFY_FAILED, "资源不存在或无权访问");
        }
        UuidAssert.match(e, uuid);
        return e;
    }

    private PassAreaListVo toListVo(MpPassAccessArea e) {
        PassAreaListVo vo = new PassAreaListVo();
        vo.setId(e.getId());
        vo.setUuid(e.getUuid());
        vo.setPid(e.getPid());
        vo.setAreaName(e.getAreaName());
        vo.setAreaDesc(e.getAreaDesc());
        vo.setCreateTime(e.getCreateTime());
        return vo;
    }

    private static String trim(String s) {
        return s == null ? null : s.trim();
    }

    private static String trimToNull(String s) {
        if (!StringUtils.hasText(s)) {
            return null;
        }
        String t = s.trim();
        return t.isEmpty() ? null : t;
    }
}