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

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.bpm.enums.task.BpmTaskStatusEnum;
import cn.iocoder.yudao.module.erp.controller.admin.purchase.vo.plan.ErpPurchasePlanPageReqVO;
import cn.iocoder.yudao.module.erp.controller.admin.purchase.vo.plan.ErpPurchasePlanRespVO;
import cn.iocoder.yudao.module.erp.controller.admin.purchase.vo.plan.ErpPurchasePlanSaveReqVO;
import cn.iocoder.yudao.module.erp.dal.dataobject.purchase.ErpPurchasePlanDO;
import cn.iocoder.yudao.module.erp.dal.dataobject.purchase.ErpPurchasePlanItemDO;
import cn.iocoder.yudao.module.erp.dal.dataobject.purchase.ErpPurchaseRequestDO;
import cn.iocoder.yudao.module.erp.dal.dataobject.purchase.ErpPurchaseRequestItemDO;
import cn.iocoder.yudao.module.erp.dal.mysql.purchase.ErpPurchasePlanItemMapper;
import cn.iocoder.yudao.module.erp.dal.mysql.purchase.ErpPurchasePlanMapper;
import cn.iocoder.yudao.module.erp.dal.mysql.purchase.ErpPurchaseRequestItemMapper;
import cn.iocoder.yudao.module.erp.dal.mysql.purchase.ErpPurchaseRequestMapper;
import cn.iocoder.yudao.module.erp.dal.redis.no.ErpNoRedisDAO;
import cn.iocoder.yudao.module.erp.enums.ErpPurchasePlanStatusEnum;
import cn.iocoder.yudao.module.erp.enums.ErpPurchaseRequestStatusEnum;
import cn.iocoder.yudao.module.mdm.api.item.MdmItemApi;
import cn.iocoder.yudao.module.mdm.api.item.dto.MdmItemRespDTO;
import cn.iocoder.yudao.module.mes.api.wms.MesWmStockApi;
import cn.iocoder.yudao.module.system.api.approval.ApprovalConfigApi;
import cn.iocoder.yudao.module.system.api.user.AdminUserApi;
import cn.iocoder.yudao.module.system.api.user.dto.AdminUserRespDTO;
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.LocalDate;
import java.time.LocalDateTime;
import java.util.*;

import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;
import static cn.iocoder.yudao.framework.common.util.collection.CollectionUtils.convertList;
import static cn.iocoder.yudao.framework.security.core.util.SecurityFrameworkUtils.getLoginUserId;
import static cn.iocoder.yudao.module.erp.enums.ErrorCodeConstants.*;

/**
 * ERP 采购计划 Service 实现类
 *
 * @author xiaoyi
 */
@Service
@Validated
@Slf4j
public class ErpPurchasePlanServiceImpl implements ErpPurchasePlanService {

    /**
     * 通用审批配置的业务类型编码（对应 system_approval_config.biz_type）
     */
    private static final String PURCHASE_PLAN_APPROVE_BIZ_TYPE = "purchase_plan_approve";

    /**
     * 需求来源：库存预警
     */
    public static final Integer DEMAND_SOURCE_STOCK_ALERT = 1;
    /**
     * 需求来源：运维/生产计划
     */
    public static final Integer DEMAND_SOURCE_PLAN = 2;

    @Resource
    private ErpPurchasePlanMapper purchasePlanMapper;
    @Resource
    private ErpPurchasePlanItemMapper purchasePlanItemMapper;

    @Resource
    private ErpPurchaseRequestMapper purchaseRequestMapper;
    @Resource
    private ErpPurchaseRequestItemMapper purchaseRequestItemMapper;

    @Resource
    private ErpNoRedisDAO noRedisDAO;

    @Resource
    private ApprovalConfigApi approvalConfigApi;

    @Resource
    private AdminUserApi adminUserApi;

    @Resource
    private MdmItemApi mdmItemApi;
    @Resource
    private MesWmStockApi mesWmStockApi;

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Long createPurchasePlan(ErpPurchasePlanSaveReqVO createReqVO) {
        // 1. 校验明细
        List<ErpPurchasePlanItemDO> planItems = convertList(createReqVO.getItems(), item ->
                BeanUtils.toBean(item, ErpPurchasePlanItemDO.class));
        if (CollUtil.isEmpty(planItems)) {
            throw exception(PURCHASE_PLAN_ITEM_EMPTY);
        }
        // 2. 生成计划单号
        String no = noRedisDAO.generate(ErpNoRedisDAO.PURCHASE_PLAN_NO_PREFIX);
        if (purchasePlanMapper.selectByNo(no) != null) {
            throw exception(PURCHASE_PLAN_NO_EXISTS);
        }
        // 3. 获取当前用户信息
        Long userId = Long.parseLong(getCurrentUserId());
        AdminUserRespDTO user = adminUserApi.getUser(userId);
        Long deptId = user != null ? user.getDeptId() : null;
        // 4. 插入采购计划
        ErpPurchasePlanDO plan = BeanUtils.toBean(createReqVO, ErpPurchasePlanDO.class, req -> req
                .setNo(no)
                .setStatus(ErpPurchasePlanStatusEnum.DRAFT.getStatus())
                .setPlanUserId(userId)
                .setPlanDeptId(deptId)
                .setGeneratedFlag(false)
                .setTotalCount(planItems.stream()
                        .map(ErpPurchasePlanItemDO::getCount).filter(Objects::nonNull)
                        .reduce(BigDecimal.ZERO, BigDecimal::add)));
        purchasePlanMapper.insert(plan);
        // 5. 插入明细
        purchasePlanItemMapper.insertBatch(convertList(planItems, item -> item.setPlanId(plan.getId())));
        return plan.getId();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updatePurchasePlan(ErpPurchasePlanSaveReqVO updateReqVO) {
        // 1.1 校验存在 + 草稿状态
        ErpPurchasePlanDO oldPlan = validatePurchasePlanCanModify(updateReqVO.getId());
        // 1.2 校验明细
        List<ErpPurchasePlanItemDO> planItems = convertList(updateReqVO.getItems(), item ->
                BeanUtils.toBean(item, ErpPurchasePlanItemDO.class));
        if (CollUtil.isEmpty(planItems)) {
            throw exception(PURCHASE_PLAN_ITEM_EMPTY);
        }
        // 2. 更新主表
        ErpPurchasePlanDO updateObj = BeanUtils.toBean(updateReqVO, ErpPurchasePlanDO.class, req -> req
                .setNo(oldPlan.getNo())
                .setStatus(oldPlan.getStatus())
                .setPlanUserId(oldPlan.getPlanUserId())
                .setPlanDeptId(oldPlan.getPlanDeptId())
                .setGeneratedFlag(oldPlan.getGeneratedFlag())
                .setTotalCount(planItems.stream()
                        .map(ErpPurchasePlanItemDO::getCount).filter(Objects::nonNull)
                        .reduce(BigDecimal.ZERO, BigDecimal::add)));
        purchasePlanMapper.updateById(updateObj);
        // 3. 更新明细：先删后插
        purchasePlanItemMapper.deleteByPlanId(updateReqVO.getId());
        purchasePlanItemMapper.insertBatch(convertList(planItems, item -> item.setPlanId(updateReqVO.getId())));
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void deletePurchasePlan(Collection<Long> ids) {
        if (CollUtil.isEmpty(ids)) {
            return;
        }
        for (Long id : ids) {
            // 1. 校验存在 + 草稿状态
            validatePurchasePlanCanModify(id);
            // 2. 删除明细
            purchasePlanItemMapper.deleteByPlanId(id);
            // 3. 删除主表
            purchasePlanMapper.deleteById(id);
        }
    }

    @Override
    public ErpPurchasePlanDO getPurchasePlan(Long id) {
        return purchasePlanMapper.selectById(id);
    }

    @Override
    public List<ErpPurchasePlanItemDO> getPurchasePlanItemListByPlanId(Long planId) {
        return purchasePlanItemMapper.selectListByPlanId(planId);
    }

    @Override
    public List<ErpPurchasePlanItemDO> getPurchasePlanItemListByPlanIds(Collection<Long> planIds) {
        return purchasePlanItemMapper.selectListByPlanIds(planIds);
    }

    @Override
    public PageResult<ErpPurchasePlanDO> getPurchasePlanPage(ErpPurchasePlanPageReqVO pageReqVO) {
        return purchasePlanMapper.selectPage(pageReqVO);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void submitPurchasePlan(Long id) {
        // 1. 校验存在 + 可提交状态（草稿 / 审核不通过）
        ErpPurchasePlanDO plan = validatePurchasePlanExists(id);
        if (!ErpPurchasePlanStatusEnum.DRAFT.getStatus().equals(plan.getStatus())
                && !ErpPurchasePlanStatusEnum.REJECT.getStatus().equals(plan.getStatus())) {
            throw exception(PURCHASE_PLAN_SUBMIT_FAIL_NOT_ALLOWED);
        }
        // 2. 校验是否有明细
        List<ErpPurchasePlanItemDO> items = purchasePlanItemMapper.selectListByPlanId(id);
        if (CollUtil.isEmpty(items)) {
            throw exception(PURCHASE_PLAN_ITEM_EMPTY);
        }
        // 3. 校验审批配置已启用且配置了有效审批人（未配置时抛出带明确提示的业务异常）
        approvalConfigApi.validateApprovalEnabledAndGetApprovers(PURCHASE_PLAN_APPROVE_BIZ_TYPE);
        // 4. 状态置为审批中，并清空上一轮审核结果，避免残留「审核不通过」的原因
        purchasePlanMapper.submitAndResetAuditInfo(id, ErpPurchasePlanStatusEnum.PROCESS.getStatus());
    }

    @Override
    public Set<Long> getPurchasePlanApproverUserIds() {
        return approvalConfigApi.getApproverUserIds(PURCHASE_PLAN_APPROVE_BIZ_TYPE);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void auditPurchasePlan(Long id, Boolean pass, String reviewRemark) {
        // 1. 校验存在
        ErpPurchasePlanDO plan = validatePurchasePlanExists(id);
        // 2. 校验处于审批中状态
        if (!ErpPurchasePlanStatusEnum.PROCESS.getStatus().equals(plan.getStatus())) {
            throw exception(PURCHASE_PLAN_AUDIT_FAIL_NOT_PROCESS);
        }
        // 3. 校验当前登录用户是该业务类型的审批人（或签：任一人均可审核）
        Long userId = getLoginUserId();
        approvalConfigApi.validateApprover(PURCHASE_PLAN_APPROVE_BIZ_TYPE, userId);
        // 4. 审核不通过：必须填写原因，状态置为审核不通过，退回编制人修改后可重新提交
        if (!Boolean.TRUE.equals(pass)) {
            if (StrUtil.isBlank(reviewRemark)) {
                throw exception(PURCHASE_PLAN_AUDIT_REJECT_REASON_REQUIRED);
            }
            purchasePlanMapper.auditPurchasePlan(id, ErpPurchasePlanStatusEnum.REJECT.getStatus(),
                    userId, getUserNickname(userId), reviewRemark);
            return;
        }
        // 5. 审核通过：记录审核人与审核意见，状态置为审核通过
        purchasePlanMapper.auditPurchasePlan(id, ErpPurchasePlanStatusEnum.APPROVE.getStatus(),
                userId, getUserNickname(userId), reviewRemark);
        // 6. 审核通过且未生成申请，自动生成采购申请
        if (!Boolean.TRUE.equals(plan.getGeneratedFlag())) {
            try {
                List<Long> requestIds = doGeneratePurchaseRequests(plan);
                log.info("[auditPurchasePlan] 采购计划({}) 自动生成采购申请({})", id, requestIds);
            } catch (Exception e) {
                // 不抛出异常，避免影响审核结果落库；生成失败可由用户手动触发
                log.error("[auditPurchasePlan] 采购计划({}) 自动生成采购申请失败", id, e);
            }
        }
    }

    /**
     * 获取用户昵称
     *
     * @param userId 用户编号
     * @return 昵称，用户不存在时返回 null
     */
    private String getUserNickname(Long userId) {
        if (userId == null) {
            return null;
        }
        AdminUserRespDTO user = adminUserApi.getUser(userId);
        return user == null ? null : user.getNickname();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updatePurchasePlanAuditStatus(Long id, Integer bpmResult) {
        // 1. 校验存在
        ErpPurchasePlanDO plan = validatePurchasePlanExists(id);
        if (!ErpPurchasePlanStatusEnum.PROCESS.getStatus().equals(plan.getStatus())) {
            log.warn("[updatePurchasePlanAuditStatus] 采购计划({}) 不处于审批中状态", id);
            return;
        }
        // 2. 根据审批结果更新状态
        Integer newStatus = convertBpmResultToStatus(bpmResult);
        if (newStatus != null) {
            purchasePlanMapper.updateById(new ErpPurchasePlanDO().setId(id).setStatus(newStatus));
        }
        // 3. 审批通过且未生成申请，自动生成采购申请
        if (ErpPurchasePlanStatusEnum.APPROVE.getStatus().equals(newStatus)
                && !Boolean.TRUE.equals(plan.getGeneratedFlag())) {
            try {
                List<Long> requestIds = doGeneratePurchaseRequests(plan);
                log.info("[updatePurchasePlanAuditStatus] 采购计划({}) 自动生成采购申请({})", id, requestIds);
            } catch (Exception e) {
                log.error("[updatePurchasePlanAuditStatus] 采购计划({}) 自动生成采购申请失败", id, e);
                // 不抛出异常，避免影响状态更新
            }
        }
    }

    @Override
    public List<ErpPurchasePlanRespVO.Item> getStockAlertSuggestItems() {
        // 1. 获取启用的物料基础数据（包含默认仓库、安全/最低/最高库存）
        List<MdmItemRespDTO> items = mdmItemApi.getItemListByStatus(0).getCheckedData();
        if (CollUtil.isEmpty(items)) {
            throw exception(PURCHASE_PLAN_STOCK_ALERT_NO_ITEM);
        }
        // 2. 按默认仓库库存规划建议采购量
        List<ErpPurchasePlanRespVO.Item> planItems = new ArrayList<>();
        for (MdmItemRespDTO item : items) {
            ErpPurchasePlanRespVO.Item planItem = buildStockAlertSuggestItem(item);
            if (planItem != null) {
                planItems.add(planItem);
            }
        }
        if (CollUtil.isEmpty(planItems)) {
            throw exception(PURCHASE_PLAN_STOCK_ALERT_NO_ITEM);
        }
        return planItems;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public ErpPurchasePlanDO generatePlanFromStockAlert(String name, Long supplierId) {
        // 1. 获取库存预警建议采购明细
        List<ErpPurchasePlanRespVO.Item> suggestItems = getStockAlertSuggestItems();
        if (CollUtil.isEmpty(suggestItems)) {
            throw exception(PURCHASE_PLAN_STOCK_ALERT_NO_ITEM);
        }
        // 2. 转换为保存明细
        List<ErpPurchasePlanSaveReqVO.Item> planItems = convertList(suggestItems, item ->
                BeanUtils.toBean(item, ErpPurchasePlanSaveReqVO.Item.class));
        // 3. 创建草稿采购计划
        ErpPurchasePlanSaveReqVO createReqVO = new ErpPurchasePlanSaveReqVO();
        createReqVO.setName(name != null ? name : "库存预警采购计划");
        createReqVO.setDemandSource(DEMAND_SOURCE_STOCK_ALERT);
        createReqVO.setPlanDate(LocalDateTime.now());
        createReqVO.setSupplierId(supplierId);
        createReqVO.setItems(planItems);
        Long planId = createPurchasePlan(createReqVO);
        return purchasePlanMapper.selectById(planId);
    }

    /**
     * 根据单个物料的默认仓库库存构建建议采购明细
     *
     * @param item 物料基础数据
     * @return 建议采购明细；无需补货时返回 null
     */
    private ErpPurchasePlanRespVO.Item buildStockAlertSuggestItem(MdmItemRespDTO item) {
        // 1. 未配置默认仓库或最低库存（无补货基准）的物料不参与规划
        if (item.getWarehouseId() == null || item.getMinStock() == null) {
            return null;
        }
        // 2. 查询默认仓库的当前库存
        BigDecimal currentStock = mesWmStockApi.getStockQuantity(item.getId(), item.getWarehouseId());
        if (currentStock == null) {
            currentStock = BigDecimal.ZERO;
        }
        // 3. 默认仓库库存不低于最低库存时不触发补货
        if (currentStock.compareTo(item.getMinStock()) >= 0) {
            return null;
        }
        // 4. 补货目标：优先补到安全库存，未配置则回落最高库存，最后取最低库存
        BigDecimal targetStock = item.getSafetyStock() != null ? item.getSafetyStock()
                : (item.getMaxStock() != null ? item.getMaxStock() : item.getMinStock());
        BigDecimal count = targetStock.subtract(currentStock);
        if (count.compareTo(BigDecimal.ZERO) <= 0) {
            return null;
        }
        ErpPurchasePlanRespVO.Item planItem = new ErpPurchasePlanRespVO.Item();
        planItem.setProductId(item.getId());
        planItem.setProductName(item.getName());
        planItem.setProductUnitId(item.getUnitMeasureId());
        planItem.setCount(count);
        planItem.setDemandTime(LocalDate.now());
        planItem.setRemark(String.format("默认仓库库存%s，安全库存%s，最低库存%s，最高库存%s，建议采购量%s",
                currentStock, item.getSafetyStock(), item.getMinStock(), item.getMaxStock(), count));
        return planItem;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public List<Long> generatePurchaseRequests(Long id) {
        // 1. 校验存在 + 审核通过状态
        ErpPurchasePlanDO plan = validatePurchasePlanExists(id);
        if (!ErpPurchasePlanStatusEnum.APPROVE.getStatus().equals(plan.getStatus())) {
            throw exception(PURCHASE_PLAN_NOT_APPROVE);
        }
        // 2. 校验是否已生成申请
        if (Boolean.TRUE.equals(plan.getGeneratedFlag())) {
            throw exception(PURCHASE_PLAN_REQUEST_EXISTS);
        }
        // 3. 生成采购申请
        return doGeneratePurchaseRequests(plan);
    }

    /**
     * 执行生成采购申请（一个计划生成一张申请单）
     *
     * @param plan 采购计划
     * @return 采购申请编号列表
     */
    private List<Long> doGeneratePurchaseRequests(ErpPurchasePlanDO plan) {
        // 1. 获取计划明细
        List<ErpPurchasePlanItemDO> planItems = purchasePlanItemMapper.selectListByPlanId(plan.getId());
        if (CollUtil.isEmpty(planItems)) {
            throw exception(PURCHASE_PLAN_ITEM_EMPTY);
        }
        // 2. 生成申请单号
        String requestNo = noRedisDAO.generate(ErpNoRedisDAO.PURCHASE_REQUEST_NO_PREFIX);
        if (purchaseRequestMapper.selectByNo(requestNo) != null) {
            throw exception(PURCHASE_REQUEST_NO_EXISTS);
        }
        // 3. 创建采购申请
        ErpPurchaseRequestDO request = new ErpPurchaseRequestDO();
        request.setNo(requestNo);
        request.setStatus(ErpPurchaseRequestStatusEnum.DRAFT.getStatus());
        request.setRequestUserId(plan.getPlanUserId());
        request.setRequestDeptId(plan.getPlanDeptId());
        request.setRequestTime(LocalDateTime.now());
        request.setSupplierId(plan.getSupplierId());
        request.setTotalCount(planItems.stream()
                .map(ErpPurchasePlanItemDO::getCount).filter(Objects::nonNull)
                .reduce(BigDecimal.ZERO, BigDecimal::add));
        request.setTotalPrice(BigDecimal.ZERO);
        request.setTotalProductPrice(BigDecimal.ZERO);
        request.setTotalTaxPrice(BigDecimal.ZERO);
        request.setRemark(plan.getRemark());
        request.setInStatus(0);
        purchaseRequestMapper.insert(request);
        // 4. 创建采购申请明细
        List<ErpPurchaseRequestItemDO> requestItems = convertList(planItems, item -> {
            ErpPurchaseRequestItemDO requestItem = new ErpPurchaseRequestItemDO();
            requestItem.setRequestId(request.getId());
            requestItem.setProductId(item.getProductId());
            requestItem.setProductUnitId(item.getProductUnitId());
            requestItem.setCount(item.getCount());
            requestItem.setDemandTime(item.getDemandTime());
            requestItem.setRemark(item.getRemark());
            requestItem.setInCount(BigDecimal.ZERO);
            return requestItem;
        });
        purchaseRequestItemMapper.insertBatch(requestItems);
        // 5. 回写计划已生成标记
        purchasePlanMapper.updateById(new ErpPurchasePlanDO()
                .setId(plan.getId()).setGeneratedFlag(true));
        return List.of(request.getId());
    }

    private Integer convertBpmResultToStatus(Integer bpmResult) {
        if (BpmTaskStatusEnum.APPROVE.getStatus().equals(bpmResult)) {
            return ErpPurchasePlanStatusEnum.APPROVE.getStatus();
        }
        if (BpmTaskStatusEnum.REJECT.getStatus().equals(bpmResult)) {
            return ErpPurchasePlanStatusEnum.REJECT.getStatus();
        }
        if (BpmTaskStatusEnum.CANCEL.getStatus().equals(bpmResult)) {
            return ErpPurchasePlanStatusEnum.CANCEL.getStatus();
        }
        return null;
    }

    private ErpPurchasePlanDO validatePurchasePlanExists(Long id) {
        ErpPurchasePlanDO plan = purchasePlanMapper.selectById(id);
        if (plan == null) {
            throw exception(PURCHASE_PLAN_NOT_EXISTS);
        }
        return plan;
    }

    private ErpPurchasePlanDO validatePurchasePlanCanModify(Long id) {
        ErpPurchasePlanDO plan = validatePurchasePlanExists(id);
        if (!ErpPurchasePlanStatusEnum.DRAFT.getStatus().equals(plan.getStatus())) {
            throw exception(PURCHASE_PLAN_UPDATE_FAIL_NOT_DRAFT, plan.getNo());
        }
        return plan;
    }

    private String getCurrentUserId() {
        return cn.iocoder.yudao.framework.security.core.util.SecurityFrameworkUtils.getLoginUserId().toString();
    }

}