package com.rongyichuang.region.service;

import com.rongyichuang.region.entity.Region;
import com.rongyichuang.region.repository.RegionRepository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.time.LocalDateTime;
import java.util.Collections;
import java.util.List;
import java.util.Optional;

@Service
@Transactional
public class RegionService {

    private static final Logger logger = LoggerFactory.getLogger(RegionService.class);
    
    @Autowired
    private RegionRepository regionRepository;
    
    /**
     * 分页查询区域
     */
    public Page<Region> findRegions(String name, Integer state, int page, int size) {
        Pageable pageable = PageRequest.of(page, size);
        return regionRepository.findByNameAndState(name, state, pageable);
    }
    
    /**
     * 查询所有区域
     */
    public List<Region> findAllRegions() {
        return regionRepository.findAll();
    }
    
    /**
     * 根据ID查找区域
     */
    public Optional<Region> findById(Long id) {
        return regionRepository.findById(id);
    }
    
    /**
     * 保存区域
     */
    public Region saveRegion(Region region) {
        if (region.getId() == null) {
            // 新增
            region.setCreateTime(LocalDateTime.now());
            region.setUpdateTime(LocalDateTime.now());
            region.setCreateUserId(1L); // 默认用户ID
            region.setUpdateUserId(1L);
            region.setVersion(0L);
        } else {
            // 更新
            region.setUpdateTime(LocalDateTime.now());
            region.setUpdateUserId(1L);
        }
        return regionRepository.save(region);
    }
    
    /**
     * 删除区域
     */
    public void deleteRegion(Long id) {
        regionRepository.deleteById(id);
    }
    
    /**
     * 切换区域状态
     */
    public Region toggleRegionState(Long id) {
        Optional<Region> regionOpt = regionRepository.findById(id);
        if (regionOpt.isPresent()) {
            Region region = regionOpt.get();
            region.setState(region.getState() == 1 ? 0 : 1);
            region.setUpdateTime(LocalDateTime.now());
            region.setUpdateUserId(1L);
            return regionRepository.save(region);
        }
        throw new RuntimeException("区域不存在");
    }
    
    /**
     * 获取省级区域列表
     */
    public List<Region> getProvinces() {
        try {
            return regionRepository.findAllProvinces();
        } catch (Exception e) {
            logger.error("!!!!!! ERROR fetching provinces:", e);
            return Collections.emptyList();
        }
    }
    
    /**
     * 获取指定省份下的城市列表
     */
    public List<Region> getCitiesByProvinceId(Long provinceId) {
        try {
            return regionRepository.findCitiesByProvinceId(provinceId);
        } catch (Exception e) {
            logger.error("!!!!!! ERROR fetching cities for province {}:", provinceId, e);
            return Collections.emptyList();
        }
    }
    
    /**
     * 获取指定城市下的区县列表
     */
    public List<Region> getDistrictsByCityId(Long cityId) {
        try {
            return regionRepository.findDistrictsByCityId(cityId);
        } catch (Exception e) {
            logger.error("!!!!!! ERROR fetching districts for city {}:", cityId, e);
            return Collections.emptyList();
        }
    }
    
    /**
     * 获取子区域列表
     */
    public List<Region> getChildren(Long parentId) {
        return regionRepository.findChildren(parentId);
    }
    
    /**
     * 构建树形结构
     */
    public List<Region> buildRegionTree() {
        List<Region> provinces = getProvinces();
        for (Region province : provinces) {
            List<Region> cities = getCitiesByProvinceId(province.getId());
            // 这里可以扩展为完整的树形结构，暂时返回省级列表
        }
        return provinces;
    }
}