package cn.iocoder.yudao.module.mes.service.safety;

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.StrUtil;
import cn.iocoder.yudao.framework.common.pojo.PageResult;
import cn.iocoder.yudao.framework.common.util.object.BeanUtils;
import cn.iocoder.yudao.module.mes.controller.admin.safety.vo.material.*;
import cn.iocoder.yudao.module.mes.dal.dataobject.safety.SafetyMaterialDO;
import cn.iocoder.yudao.module.mes.dal.dataobject.safety.SafetyMaterialStockDO;
import cn.iocoder.yudao.module.mes.dal.mysql.safety.SafetyMaterialMapper;
import cn.iocoder.yudao.module.mes.dal.mysql.safety.SafetyMaterialStockMapper;
import cn.iocoder.yudao.module.mes.enums.safety.SafetyMaterialCategoryEnum;
import jakarta.annotation.Resource;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.validation.annotation.Validated;

import java.math.BigDecimal;
import java.time.LocalDate;
import java.time.temporal.ChronoUnit;
import java.util.List;

import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;
import static cn.iocoder.yudao.module.mes.enums.SafetyErrorCodeConstants.*;

/**
 * 安全生产 - 应急物资台账与出入库 Service
 *
 * <p>覆盖电力绝缘用具、危化品、消防物资。出库时行锁校验库存，避免并发扣减为负。</p>
 *
 * @author 超级管理员
 */
@Service
@Validated
public class SafetyMaterialService {

    @Resource
    private SafetyMaterialMapper materialMapper;
    @Resource
    private SafetyRefResolver refResolver;
    @Resource
    private SafetyMaterialStockMapper stockMapper;

    // ==================== 物资台账 ====================

    public Long createMaterial(SafetyMaterialSaveReqVO reqVO) {
        reqVO.setId(null);
        String code = StrUtil.trim(reqVO.getCode());
        if (materialMapper.selectByCode(code) != null) {
            throw exception(SAFETY_MATERIAL_CODE_DUPLICATE);
        }
        SafetyMaterialDO material = BeanUtils.toBean(reqVO, SafetyMaterialDO.class);
        material.setCode(code);
        material.setName(StrUtil.trim(reqVO.getName()));
        material.setUnit(StrUtil.blankToDefault(reqVO.getUnit(), "个"));
        applyManager(material, reqVO.getManagerId());
        material.setStockQty(reqVO.getStockQty() == null ? BigDecimal.ZERO : reqVO.getStockQty());
        material.setSafeStock(reqVO.getSafeStock() == null ? BigDecimal.ZERO : reqVO.getSafeStock());
        materialMapper.insert(material);
        return material.getId();
    }

    public void updateMaterial(SafetyMaterialSaveReqVO reqVO) {
        SafetyMaterialDO old = validateMaterialExists(reqVO.getId());
        String code = StrUtil.trim(reqVO.getCode());
        SafetyMaterialDO byCode = materialMapper.selectByCode(code);
        if (byCode != null && !byCode.getId().equals(old.getId())) {
            throw exception(SAFETY_MATERIAL_CODE_DUPLICATE);
        }
        SafetyMaterialDO material = BeanUtils.toBean(reqVO, SafetyMaterialDO.class);
        material.setCode(code);
        material.setName(StrUtil.trim(reqVO.getName()));
        applyManager(material, reqVO.getManagerId());
        // 库存数量只能通过出入库单变动，禁止直接编辑
        material.setStockQty(null);
        materialMapper.updateById(material);
    }

    public void deleteMaterial(Long id) {
        validateMaterialExists(id);
        materialMapper.deleteById(id);
    }

    public SafetyMaterialDO getMaterial(Long id) {
        return validateMaterialExists(id);
    }

    public PageResult<SafetyMaterialDO> getMaterialPage(SafetyMaterialPageReqVO reqVO) {
        return materialMapper.selectPage(reqVO);
    }

    /**
     * 保管人：从员工档案带出姓名落快照
     */
    private void applyManager(SafetyMaterialDO material, Long managerId) {
        material.setManagerId(managerId);
        material.setManager(managerId == null ? ""
                : refResolver.requireEmployee(managerId, SAFETY_EMPLOYEE_REQUIRED).getName());
    }

    /**
     * 批量回填保管人最新姓名
     */
    public void fillManagers(List<SafetyMaterialDO> materials) {
        if (CollUtil.isEmpty(materials)) {
            return;
        }
        var employeeMap = refResolver.employeeMap(materials.stream().map(SafetyMaterialDO::getManagerId).toList());
        materials.forEach(material -> {
            var employee = employeeMap.get(material.getManagerId());
            if (employee != null) material.setManager(employee.getName());
        });
    }

    public static void fillMaterialDisplay(SafetyMaterialDO material, SafetyMaterialRespVO respVO) {
        respVO.setCategoryName(SafetyMaterialCategoryEnum.getNameByCategory(material.getCategory()));
        BigDecimal stock = material.getStockQty() == null ? BigDecimal.ZERO : material.getStockQty();
        BigDecimal safe = material.getSafeStock() == null ? BigDecimal.ZERO : material.getSafeStock();
        respVO.setBelowSafeStock(safe.signum() > 0 && stock.compareTo(safe) < 0);
        if (material.getExpireDate() != null) {
            respVO.setExpireRemainingDays(ChronoUnit.DAYS.between(LocalDate.now(), material.getExpireDate()));
        }
    }

    // ==================== 出入库 ====================

    /**
     * 出入库登记：行锁读取库存 → 计算变动 → 写流水 → 回写库存
     */
    @Transactional(rollbackFor = Exception.class)
    public Long createStock(SafetyMaterialStockSaveReqVO reqVO) {
        SafetyMaterialDO material = materialMapper.selectByIdForUpdate(reqVO.getMaterialId());
        if (material == null) {
            throw exception(SAFETY_MATERIAL_NOT_EXISTS);
        }
        BigDecimal before = material.getStockQty() == null ? BigDecimal.ZERO : material.getStockQty();
        boolean inbound = "IN".equals(reqVO.getBizType());
        BigDecimal after = inbound ? before.add(reqVO.getQuantity()) : before.subtract(reqVO.getQuantity());
        if (!inbound && after.signum() < 0) {
            throw exception(SAFETY_MATERIAL_STOCK_NOT_ENOUGH);
        }
        SafetyMaterialStockDO stock = BeanUtils.toBean(reqVO, SafetyMaterialStockDO.class);
        stock.setId(null);
        stock.setMaterialName(material.getName());
        stock.setCategory(material.getCategory());
        stock.setQuantity(reqVO.getQuantity());
        stock.setStockBefore(before);
        stock.setStockAfter(after);
        stock.setBizDate(reqVO.getBizDate() == null ? LocalDate.now() : reqVO.getBizDate());
        stock.setOperator(StrUtil.trim(reqVO.getOperator()));
        stockMapper.insert(stock);

        SafetyMaterialDO update = new SafetyMaterialDO();
        update.setId(material.getId());
        update.setStockQty(after);
        materialMapper.updateById(update);
        return stock.getId();
    }

    public PageResult<SafetyMaterialStockDO> getStockPage(SafetyMaterialStockPageReqVO reqVO) {
        return stockMapper.selectPage(reqVO);
    }

    public static void fillStockDisplay(SafetyMaterialStockDO stock, SafetyMaterialStockRespVO respVO) {
        respVO.setCategoryName(SafetyMaterialCategoryEnum.getNameByCategory(stock.getCategory()));
        respVO.setBizTypeName("IN".equals(stock.getBizType()) ? "入库" : "出库");
    }

    /**
     * 预警清单：低于安全库存的物资
     */
    public List<SafetyMaterialDO> getBelowSafeStockList() {
        return materialMapper.selectBelowSafeStock();
    }

    /**
     * 预警清单：有效期临近（默认 30 天内）的物资
     */
    public List<SafetyMaterialDO> getExpiringList(Integer days) {
        int warnDays = days == null || days <= 0 ? 30 : days;
        return materialMapper.selectExpiringBefore(LocalDate.now().plusDays(warnDays));
    }

    private SafetyMaterialDO validateMaterialExists(Long id) {
        SafetyMaterialDO material = id == null ? null : materialMapper.selectById(id);
        if (material == null) {
            throw exception(SAFETY_MATERIAL_NOT_EXISTS);
        }
        return material;
    }

}