package cn.iocoder.yudao.module.wms.service.inventory;

import cn.iocoder.yudao.framework.common.pojo.PageResult;
import cn.iocoder.yudao.framework.common.util.object.BeanUtils;
import cn.iocoder.yudao.module.wms.api.inventory.dto.*;
import cn.iocoder.yudao.module.wms.controller.admin.inventory.vo.WmsInventoryReservePageReqVO;
import cn.iocoder.yudao.module.wms.dal.dataobject.inventory.WmsInventoryReserveDO;
import cn.iocoder.yudao.module.wms.dal.dataobject.inventory.WmsInventoryTransactionDO;
import cn.iocoder.yudao.module.wms.dal.mysql.inventory.WmsInventoryReserveMapper;
import cn.iocoder.yudao.module.wms.dal.mysql.inventory.WmsInventoryTransactionMapper;
import cn.iocoder.yudao.module.wms.enums.inventory.WmsReserveStatusEnum;
import cn.iocoder.yudao.module.wms.enums.inventory.WmsTransactionTypeEnum;
import cn.iocoder.yudao.module.wms.service.inventory.dto.WmsInventoryChangeReqDTO;
import jakarta.annotation.Resource;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.validation.annotation.Validated;

import java.math.BigDecimal;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.List;
import java.util.UUID;

import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;
import static cn.iocoder.yudao.module.wms.enums.ErrorCodeConstants.*;

/**
 * WMS 库存预留 Service 实现类
 *
 * @author 芋道源码
 */
@Service
@Validated
@Slf4j
public class WmsInventoryReserveServiceImpl implements WmsInventoryReserveService {

    @Resource
    private WmsInventoryReserveMapper reserveMapper;

    @Resource
    private WmsInventoryTransactionMapper transactionMapper;

    @Resource
    private WmsInventoryService inventoryService;

    @Resource
    private WmsInventoryTransactionService transactionService;

    @Override
    @Transactional(rollbackFor = Exception.class)
    public String createReserve(WmsReserveReqDTO reqDTO) {
        // 1. 校验可用库存
        BigDecimal availableQuantity = inventoryService.getAvailableQuantity(reqDTO.getSkuId(), reqDTO.getWarehouseId());
        if (availableQuantity.compareTo(reqDTO.getQuantity()) < 0) {
            throw exception(INVENTORY_QUANTITY_NOT_ENOUGH_FOR_RESERVE,
                    reqDTO.getSkuId(), reqDTO.getWarehouseId(), availableQuantity, reqDTO.getQuantity());
        }

        // 2. 生成预留单号
        String reserveNo = generateReserveNo();

        // 3. 创建预留记录
        WmsInventoryReserveDO reserve = BeanUtils.toBean(reqDTO, WmsInventoryReserveDO.class);
        reserve.setReserveNo(reserveNo);
        reserve.setReserveQuantity(reqDTO.getQuantity());
        reserve.setUsedQuantity(BigDecimal.ZERO);
        reserve.setStatus(WmsReserveStatusEnum.RESERVED.getStatus());
        reserveMapper.insert(reserve);

        // 4. 记录事务流水
        transactionService.createTransaction(buildReserveTransaction(reserve, reqDTO.getQuantity()));

        return reserveNo;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void releaseReserve(String reserveNo) {
        // 1. 查询预留记录
        WmsInventoryReserveDO reserve = reserveMapper.selectByReserveNo(reserveNo);
        if (reserve == null) {
            throw exception(INVENTORY_RESERVE_NOT_EXISTS);
        }
        // 1.1 校验状态：只有预留中或部分使用状态可释放
        if (reserve.getStatus() != WmsReserveStatusEnum.RESERVED.getStatus()
                && reserve.getStatus() != WmsReserveStatusEnum.PARTIAL_USED.getStatus()) {
            throw exception(INVENTORY_RESERVE_STATUS_INVALID);
        }

        // 2. 计算释放数量
        BigDecimal releaseQuantity = reserve.getReserveQuantity().subtract(reserve.getUsedQuantity());

        // 3. 更新预留状态
        reserve.setStatus(WmsReserveStatusEnum.RELEASED.getStatus());
        reserveMapper.updateById(reserve);

        // 4. 记录事务流水（释放为负数）
        transactionService.createTransaction(buildReleaseTransaction(reserve, releaseQuantity.negate()));
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void useReserve(WmsUseReserveReqDTO reqDTO) {
        // 1. 查询预留记录
        WmsInventoryReserveDO reserve = reserveMapper.selectByReserveNo(reqDTO.getReserveNo());
        if (reserve == null) {
            throw exception(INVENTORY_RESERVE_NOT_EXISTS);
        }
        // 1.1 校验状态
        if (reserve.getStatus() != WmsReserveStatusEnum.RESERVED.getStatus()
                && reserve.getStatus() != WmsReserveStatusEnum.PARTIAL_USED.getStatus()) {
            throw exception(INVENTORY_RESERVE_STATUS_INVALID);
        }

        // 2. 计算剩余可使用数量
        BigDecimal remainQuantity = reserve.getReserveQuantity().subtract(reserve.getUsedQuantity());
        if (reqDTO.getQuantity().compareTo(remainQuantity) > 0) {
            throw exception(INVENTORY_RESERVE_QUANTITY_NOT_ENOUGH, reqDTO.getReserveNo(), remainQuantity, reqDTO.getQuantity());
        }

        // 3. 更新已使用数量和状态
        BigDecimal newUsedQuantity = reserve.getUsedQuantity().add(reqDTO.getQuantity());
        reserve.setUsedQuantity(newUsedQuantity);
        if (newUsedQuantity.compareTo(reserve.getReserveQuantity()) == 0) {
            reserve.setStatus(WmsReserveStatusEnum.USED.getStatus());
        } else {
            reserve.setStatus(WmsReserveStatusEnum.PARTIAL_USED.getStatus());
        }
        reserveMapper.updateById(reserve);
    }

    @Override
    public List<WmsInventoryReserveDO> getReserveListByBiz(Integer bizType, Long bizId) {
        return reserveMapper.selectListByBiz(bizType, bizId);
    }

    @Override
    public PageResult<WmsInventoryReserveDO> getReservePage(WmsInventoryReservePageReqVO reqVO) {
        return reserveMapper.selectPage(reqVO);
    }

    @Override
    public WmsInventoryReserveDO getReserve(Long id) {
        return reserveMapper.selectById(id);
    }

    @Override
    public BigDecimal getReserveQuantity(Long skuId, Long warehouseId) {
        return reserveMapper.selectReserveQuantity(skuId, warehouseId);
    }

    /**
     * 生成预留单号
     */
    private String generateReserveNo() {
        return "RES" + LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyyMMdd"))
                + UUID.randomUUID().toString().substring(0, 8).toUpperCase();
    }

    /**
     * 构建预留事务流水
     */
    private WmsInventoryTransactionDO buildReserveTransaction(WmsInventoryReserveDO reserve, BigDecimal quantity) {
        return WmsInventoryTransactionDO.builder()
                .transactionNo(generateTransactionNo())
                .transactionType(WmsTransactionTypeEnum.RESERVE.getType())
                .bizType(reserve.getBizType())
                .bizId(reserve.getBizId())
                .bizNo(reserve.getBizNo())
                .skuId(reserve.getSkuId())
                .warehouseId(reserve.getWarehouseId())
                .quantity(quantity)
                .reserveId(reserve.getId())
                .reserveNo(reserve.getReserveNo())
                .transactionTime(LocalDateTime.now())
                .remark(reserve.getRemark())
                .build();
    }

    /**
     * 构建释放事务流水
     */
    private WmsInventoryTransactionDO buildReleaseTransaction(WmsInventoryReserveDO reserve, BigDecimal quantity) {
        return WmsInventoryTransactionDO.builder()
                .transactionNo(generateTransactionNo())
                .transactionType(WmsTransactionTypeEnum.RELEASE.getType())
                .bizType(reserve.getBizType())
                .bizId(reserve.getBizId())
                .bizNo(reserve.getBizNo())
                .skuId(reserve.getSkuId())
                .warehouseId(reserve.getWarehouseId())
                .quantity(quantity)
                .reserveId(reserve.getId())
                .reserveNo(reserve.getReserveNo())
                .transactionTime(LocalDateTime.now())
                .remark("释放预留")
                .build();
    }

    /**
     * 生成事务流水号
     */
    private String generateTransactionNo() {
        return "TRX" + LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyyMMddHHmmss"))
                + UUID.randomUUID().toString().substring(0, 6).toUpperCase();
    }

}