package cn.iocoder.yudao.module.erp.service.stock;

import cn.hutool.core.collection.CollUtil;
import cn.iocoder.yudao.framework.common.pojo.PageResult;
import cn.iocoder.yudao.module.erp.controller.admin.stock.vo.stock.ErpStockPageReqVO;
import cn.iocoder.yudao.module.erp.dal.dataobject.stock.ErpStockDO;
import cn.iocoder.yudao.module.erp.dal.mysql.stock.ErpStockMapper;
import cn.iocoder.yudao.module.erp.service.product.ErpProductService;
import cn.iocoder.yudao.module.erp.service.stock.ErpWarehouseService;
import cn.iocoder.yudao.module.mdm.api.item.MdmItemSkuApi;
import cn.iocoder.yudao.module.mdm.api.item.dto.MdmItemSkuRespDTO;
import cn.iocoder.yudao.module.wms.api.inventory.WmsInventoryApi;
import cn.iocoder.yudao.module.wms.api.inventory.dto.WmsInventoryQueryReqDTO;
import cn.iocoder.yudao.module.wms.api.inventory.dto.WmsInventoryRespDTO;
import jakarta.annotation.Resource;
import org.springframework.stereotype.Service;
import org.springframework.validation.annotation.Validated;

import java.math.BigDecimal;
import java.util.List;

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

/**
 * ERP 产品库存 Service 实现类
 *
 * 改造说明：ERP 库存调用 WMS 库存 API
 * - productId 对应 MDM itemId
 * - 通过 MDM SKU API 获取物料的默认 SKU
 * - 库存操作调用 WMS Inventory API
 *
 * @author 芋道源码
 */
@Service
@Validated
public class ErpStockServiceImpl implements ErpStockService {

    /**
     * 允许库存为负数
     * TODO 芋艿：后续做成 db 配置
     */
    private static final Boolean NEGATIVE_STOCK_COUNT_ENABLE = false;

    @Resource
    private ErpProductService productService;

    @Resource
    private ErpWarehouseService warehouseService;

    @Resource
    private ErpStockMapper stockMapper;

    @Resource
    private WmsInventoryApi wmsInventoryApi;

    @Resource
    private MdmItemSkuApi mdmItemSkuApi;

    @Override
    public ErpStockDO getStock(Long id) {
        return stockMapper.selectById(id);
    }

    @Override
    public ErpStockDO getStock(Long productId, Long warehouseId) {
        // 通过 MDM 获取产品的默认 SKU，然后查询 WMS 库存
        Long skuId = getDefaultSkuId(productId);
        if (skuId == null) {
            return null;
        }

        // 查询 WMS 库存
        BigDecimal quantity = wmsInventoryApi.getAvailableQuantity(skuId, warehouseId).getCheckedData();
        if (quantity == null || quantity.compareTo(BigDecimal.ZERO) == 0) {
            return null;
        }

        // 转换为 ERP Stock DO
        ErpStockDO stock = new ErpStockDO();
        stock.setProductId(productId);
        stock.setWarehouseId(warehouseId);
        stock.setCount(quantity);
        return stock;
    }

    @Override
    public BigDecimal getStockCount(Long productId) {
        // 通过 MDM 获取产品的默认 SKU，然后查询 WMS 库存总量
        Long skuId = getDefaultSkuId(productId);
        if (skuId == null) {
            return BigDecimal.ZERO;
        }

        // 查询该 SKU 在所有仓库的库存
        WmsInventoryQueryReqDTO queryReq = new WmsInventoryQueryReqDTO();
        queryReq.setSkuIds(List.of(skuId));
        queryReq.setOnlyPositive(true);

        List<WmsInventoryRespDTO> inventories = wmsInventoryApi.getInventoryList(queryReq).getCheckedData();
        if (CollUtil.isEmpty(inventories)) {
            return BigDecimal.ZERO;
        }

        return inventories.stream()
                .map(WmsInventoryRespDTO::getQuantity)
                .filter(q -> q != null)
                .reduce(BigDecimal.ZERO, BigDecimal::add);
    }

    @Override
    public PageResult<ErpStockDO> getStockPage(ErpStockPageReqVO pageReqVO) {
        // 暂时保留原逻辑，后续可改为调用 WMS 分页 API
        return stockMapper.selectPage(pageReqVO);
    }

    @Override
    public BigDecimal updateStockCountIncrement(Long productId, Long warehouseId, BigDecimal count) {
        // 通过 MDM 获取产品的默认 SKU
        Long skuId = getDefaultSkuId(productId);
        if (skuId == null) {
            throw exception(STOCK_COUNT_NEGATIVE2,
                    productService.getProduct(productId).getName(),
                    warehouseService.getWarehouse(warehouseId).getName());
        }

        // 查询当前库存
        BigDecimal currentStock = wmsInventoryApi.getAvailableQuantity(skuId, warehouseId).getCheckedData();
        if (currentStock == null) {
            currentStock = BigDecimal.ZERO;
        }

        // 校验库存是否充足（出库时）
        if (!NEGATIVE_STOCK_COUNT_ENABLE && count.compareTo(BigDecimal.ZERO) < 0) {
            BigDecimal afterStock = currentStock.add(count);
            if (afterStock.compareTo(BigDecimal.ZERO) < 0) {
                throw exception(STOCK_COUNT_NEGATIVE,
                        productService.getProduct(productId).getName(),
                        warehouseService.getWarehouse(warehouseId).getName(),
                        currentStock, count.abs());
            }
        }

        // TODO: 调用 WMS 库存变更 API（需要 WMS 提供 increment/decrement 方法）
        // 暂时保留原逻辑，使用本地库存表
        ErpStockDO stock = stockMapper.selectByProductIdAndWarehouseId(productId, warehouseId);
        if (stock == null) {
            stock = new ErpStockDO()
                    .setProductId(productId)
                    .setWarehouseId(warehouseId)
                    .setCount(BigDecimal.ZERO);
            stockMapper.insert(stock);
        }

        int updateCount = stockMapper.updateCountIncrement(stock.getId(), count, NEGATIVE_STOCK_COUNT_ENABLE);
        if (updateCount == 0) {
            throw exception(STOCK_COUNT_NEGATIVE2,
                    productService.getProduct(productId).getName(),
                    warehouseService.getWarehouse(warehouseId).getName());
        }

        return stock.getCount().add(count);
    }

    /**
     * 获取产品的默认 SKU ID
     * ERP productId 对应 MDM itemId，默认使用第一个 SKU
     */
    private Long getDefaultSkuId(Long productId) {
        if (productId == null) {
            return null;
        }
        List<MdmItemSkuRespDTO> skuList = mdmItemSkuApi.getItemSkuListByItemId(productId).getCheckedData();
        if (CollUtil.isEmpty(skuList)) {
            return null;
        }
        return skuList.get(0).getId();
    }

}