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

import cn.hutool.core.collection.CollUtil;
import cn.iocoder.yudao.framework.common.pojo.PageResult;
import cn.iocoder.yudao.framework.common.util.number.MoneyUtils;
import cn.iocoder.yudao.framework.common.util.object.BeanUtils;
import cn.iocoder.yudao.module.bpm.api.task.BpmProcessInstanceApi;
import cn.iocoder.yudao.module.bpm.api.task.dto.BpmProcessInstanceCreateReqDTO;
import cn.iocoder.yudao.module.bpm.dal.dataobject.definition.BpmCategoryDO;
import cn.iocoder.yudao.module.bpm.dal.dataobject.definition.BpmProcessDefinitionInfoDO;
import cn.iocoder.yudao.module.bpm.enums.task.BpmTaskStatusEnum;
import cn.iocoder.yudao.module.bpm.service.definition.BpmCategoryService;
import cn.iocoder.yudao.module.bpm.service.definition.BpmProcessDefinitionService;
import cn.iocoder.yudao.module.erp.controller.admin.purchase.vo.request.ErpPurchaseRequestPageReqVO;
import cn.iocoder.yudao.module.erp.controller.admin.purchase.vo.request.ErpPurchaseRequestSaveReqVO;
import cn.iocoder.yudao.module.erp.dal.dataobject.purchase.ErpPurchaseOrderDO;
import cn.iocoder.yudao.module.erp.dal.dataobject.purchase.ErpPurchaseOrderItemDO;
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.ErpPurchaseOrderItemMapper;
import cn.iocoder.yudao.module.erp.dal.mysql.purchase.ErpPurchaseOrderMapper;
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.ErpAuditStatus;
import cn.iocoder.yudao.module.erp.enums.ErpPurchaseRequestStatusEnum;
import cn.iocoder.yudao.module.system.api.dept.DeptApi;
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.flowable.engine.repository.ProcessDefinition;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.validation.annotation.Validated;

import java.math.BigDecimal;
import java.util.*;

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

/**
 * ERP 采购申请 Service 实现类
 */
@Service
@Validated
@Slf4j
public class ErpPurchaseRequestServiceImpl implements ErpPurchaseRequestService {

    /**
     * BPM 采购申请审批分类编码
     */
    private static final String PURCHASE_REQUEST_APPROVE_CATEGORY_CODE = "purchase_request_approve";

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

    @Resource
    private ErpPurchaseOrderMapper purchaseOrderMapper;
    @Resource
    private ErpPurchaseOrderItemMapper purchaseOrderItemMapper;

    @Resource
    private ErpNoRedisDAO noRedisDAO;

    @Resource
    private ErpSupplierService supplierService;

    @Resource
    private BpmProcessInstanceApi processInstanceApi;
    @Resource
    private BpmCategoryService bpmCategoryService;
    @Resource
    private BpmProcessDefinitionService bpmProcessDefinitionService;

    @Resource
    private AdminUserApi adminUserApi;
    @Resource
    private DeptApi deptApi;

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Long createPurchaseRequest(ErpPurchaseRequestSaveReqVO createReqVO) {
        // 1. 校验订单项的有效性
        List<ErpPurchaseRequestItemDO> requestItems = validatePurchaseRequestItems(createReqVO.getItems());
        // 2. 校验供应商（如果指定）
        if (createReqVO.getSupplierId() != null) {
            supplierService.validateSupplier(createReqVO.getSupplierId());
        }
        // 3. 生成申请单号
        String no = noRedisDAO.generate(ErpNoRedisDAO.PURCHASE_REQUEST_NO_PREFIX);
        if (purchaseRequestMapper.selectByNo(no) != null) {
            throw exception(PURCHASE_REQUEST_NO_EXISTS);
        }

        // 4. 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;

        // 5. 插入申请单
        ErpPurchaseRequestDO purchaseRequest = BeanUtils.toBean(createReqVO, ErpPurchaseRequestDO.class, req -> req
                .setNo(no)
                .setStatus(ErpPurchaseRequestStatusEnum.DRAFT.getStatus())
                .setRequestUserId(userId)
                .setRequestDeptId(deptId));
        calculateTotalPrice(purchaseRequest, requestItems);
        purchaseRequestMapper.insert(purchaseRequest);

        // 6. 插入申请明细
        requestItems.forEach(o -> o.setRequestId(purchaseRequest.getId()));
        purchaseRequestItemMapper.insertBatch(requestItems);

        return purchaseRequest.getId();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updatePurchaseRequest(ErpPurchaseRequestSaveReqVO updateReqVO) {
        // 1. 校验存在 + 草稿状态
        ErpPurchaseRequestDO purchaseRequest = validatePurchaseRequestExistsAndDraft(updateReqVO.getId());
        // 2. 校验供应商（如果指定）
        if (updateReqVO.getSupplierId() != null) {
            supplierService.validateSupplier(updateReqVO.getSupplierId());
        }
        // 3. 校验订单项的有效性
        List<ErpPurchaseRequestItemDO> requestItems = validatePurchaseRequestItems(updateReqVO.getItems());

        // 4. 更新申请单
        ErpPurchaseRequestDO updateObj = BeanUtils.toBean(updateReqVO, ErpPurchaseRequestDO.class);
        calculateTotalPrice(updateObj, requestItems);
        purchaseRequestMapper.updateById(updateObj);

        // 5. 更新申请明细
        updatePurchaseRequestItemList(updateReqVO.getId(), requestItems);
    }

    private void calculateTotalPrice(ErpPurchaseRequestDO purchaseRequest, List<ErpPurchaseRequestItemDO> requestItems) {
        purchaseRequest.setTotalCount(getSumValue(requestItems, ErpPurchaseRequestItemDO::getCount, BigDecimal::add));
        purchaseRequest.setTotalProductPrice(getSumValue(requestItems, ErpPurchaseRequestItemDO::getTotalPrice, BigDecimal::add, BigDecimal.ZERO));
        purchaseRequest.setTotalTaxPrice(getSumValue(requestItems, ErpPurchaseRequestItemDO::getTaxPrice, BigDecimal::add, BigDecimal.ZERO));
        purchaseRequest.setTotalPrice(purchaseRequest.getTotalProductPrice().add(purchaseRequest.getTotalTaxPrice()));
        // 计算优惠价格
        if (purchaseRequest.getDiscountPercent() == null) {
            purchaseRequest.setDiscountPercent(BigDecimal.ZERO);
        }
        purchaseRequest.setDiscountPrice(MoneyUtils.priceMultiplyPercent(purchaseRequest.getTotalPrice(), purchaseRequest.getDiscountPercent()));
        purchaseRequest.setTotalPrice(purchaseRequest.getTotalPrice().subtract(purchaseRequest.getDiscountPrice()));
    }

    private List<ErpPurchaseRequestItemDO> validatePurchaseRequestItems(List<ErpPurchaseRequestSaveReqVO.Item> list) {
        return convertList(list, o -> BeanUtils.toBean(o, ErpPurchaseRequestItemDO.class, item -> {
            if (item.getProductPrice() != null && item.getCount() != null) {
                item.setTotalPrice(MoneyUtils.priceMultiply(item.getProductPrice(), item.getCount()));
                if (item.getTaxPercent() != null) {
                    item.setTaxPrice(MoneyUtils.priceMultiplyPercent(item.getTotalPrice(), item.getTaxPercent()));
                }
            }
        }));
    }

    private void updatePurchaseRequestItemList(Long id, List<ErpPurchaseRequestItemDO> newList) {
        List<ErpPurchaseRequestItemDO> oldList = purchaseRequestItemMapper.selectListByRequestId(id);
        List<List<ErpPurchaseRequestItemDO>> diffList = diffList(oldList, newList,
                (oldVal, newVal) -> oldVal.getId().equals(newVal.getId()));

        if (CollUtil.isNotEmpty(diffList.get(0))) {
            diffList.get(0).forEach(o -> o.setRequestId(id));
            purchaseRequestItemMapper.insertBatch(diffList.get(0));
        }
        if (CollUtil.isNotEmpty(diffList.get(1))) {
            purchaseRequestItemMapper.updateBatch(diffList.get(1));
        }
        if (CollUtil.isNotEmpty(diffList.get(2))) {
            purchaseRequestItemMapper.deleteByIds(convertList(diffList.get(2), ErpPurchaseRequestItemDO::getId));
        }
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void deletePurchaseRequest(List<Long> ids) {
        List<ErpPurchaseRequestDO> purchaseRequests = purchaseRequestMapper.selectRequestListByIds(ids);
        if (CollUtil.isEmpty(purchaseRequests)) {
            return;
        }
        purchaseRequests.forEach(purchaseRequest -> {
            // 只有草稿状态才能删除
            if (!ErpPurchaseRequestStatusEnum.DRAFT.getStatus().equals(purchaseRequest.getStatus())) {
                throw exception(PURCHASE_REQUEST_DELETE_FAIL_NOT_DRAFT, purchaseRequest.getNo());
            }
        });

        purchaseRequests.forEach(purchaseRequest -> {
            purchaseRequestMapper.deleteById(purchaseRequest.getId());
            purchaseRequestItemMapper.deleteByRequestId(purchaseRequest.getId());
        });
    }

    @Override
    public ErpPurchaseRequestDO getPurchaseRequest(Long id) {
        return purchaseRequestMapper.selectById(id);
    }

    @Override
    public PageResult<ErpPurchaseRequestDO> getPurchaseRequestPage(ErpPurchaseRequestPageReqVO pageReqVO) {
        return purchaseRequestMapper.selectPage(pageReqVO);
    }

    @Override
    public List<ErpPurchaseRequestItemDO> getPurchaseRequestItemListByRequestId(Long requestId) {
        return purchaseRequestItemMapper.selectListByRequestId(requestId);
    }

    @Override
    public List<ErpPurchaseRequestItemDO> getPurchaseRequestItemListByRequestIds(Collection<Long> requestIds) {
        if (CollUtil.isEmpty(requestIds)) {
            return Collections.emptyList();
        }
        return purchaseRequestItemMapper.selectListByRequestIds(requestIds);
    }

    @Override
    public List<ErpPurchaseRequestDO> getPurchaseRequestList(List<Long> ids) {
        if (CollUtil.isEmpty(ids)) {
            return Collections.emptyList();
        }
        return purchaseRequestMapper.selectRequestListByIds(ids);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void submitPurchaseRequest(Long id, String processDefinitionKey, Long userId) {
        // 1. 校验存在 + 草稿状态
        ErpPurchaseRequestDO purchaseRequest = validatePurchaseRequestExistsAndDraft(id);

        // 2. 校验是否有明细
        List<ErpPurchaseRequestItemDO> items = purchaseRequestItemMapper.selectListByRequestId(id);
        if (CollUtil.isEmpty(items)) {
            throw exception(PURCHASE_REQUEST_NOT_EXISTS); // TODO: 添加明细为空的错误码
        }

        // 3. 创建 BPM 流程实例
        String processInstanceId = processInstanceApi.createProcessInstance(userId,
                new BpmProcessInstanceCreateReqDTO()
                        .setProcessDefinitionKey(processDefinitionKey)
                        .setBusinessKey(String.valueOf(id)));

        // 4. 更新采购申请状态为审批中
        purchaseRequestMapper.updateById(new ErpPurchaseRequestDO()
                .setId(id)
                .setStatus(ErpPurchaseRequestStatusEnum.PROCESS.getStatus())
                .setProcessInstanceId(processInstanceId));
    }

    @Override
    public List<Map<String, Object>> getPurchaseRequestApproveProcessDefinitionList() {
        // 1. 校验分类和流程定义是否存在
        validatePurchaseRequestApproveCategoryAndProcessDefinition();

        // 2. 获取分类下的流程定义信息
        List<BpmProcessDefinitionInfoDO> definitionInfoList = bpmProcessDefinitionService
                .getProcessDefinitionInfoListByCategory(PURCHASE_REQUEST_APPROVE_CATEGORY_CODE);
        if (CollUtil.isEmpty(definitionInfoList)) {
            return Collections.emptyList();
        }

        // 3. 遍历获取流程定义详情，过滤激活状态，保留最新版本
        Map<String, ProcessDefinition> latestVersionMap = new HashMap<>();
        for (BpmProcessDefinitionInfoDO info : definitionInfoList) {
            ProcessDefinition pd = bpmProcessDefinitionService.getProcessDefinition(info.getProcessDefinitionId());
            if (pd == null || pd.isSuspended()) {
                continue;
            }
            ProcessDefinition existing = latestVersionMap.get(pd.getKey());
            if (existing == null || pd.getVersion() > existing.getVersion()) {
                latestVersionMap.put(pd.getKey(), pd);
            }
        }

        // 4. 返回流程定义列表
        List<Map<String, Object>> result = new ArrayList<>();
        for (ProcessDefinition pd : latestVersionMap.values()) {
            Map<String, Object> item = new HashMap<>();
            item.put("id", pd.getId());
            item.put("key", pd.getKey());
            item.put("name", pd.getName());
            result.add(item);
        }
        return result;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updatePurchaseRequestAuditStatus(Long id, Integer bpmResult) {
        // 1. 校验存在
        ErpPurchaseRequestDO purchaseRequest = validatePurchaseRequestExists(id);
        if (!ErpPurchaseRequestStatusEnum.PROCESS.getStatus().equals(purchaseRequest.getStatus())) {
            log.warn("[updatePurchaseRequestAuditStatus] 采购申请({}) 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) {
            purchaseRequestMapper.updateById(new ErpPurchaseRequestDO()
                    .setId(id).setStatus(newStatus));
        }
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Long generatePurchaseOrder(Long id, Long supplierId) {
        // 1. 校验存在 + 审核通过状态
        ErpPurchaseRequestDO purchaseRequest = validatePurchaseRequestExists(id);
        if (!ErpPurchaseRequestStatusEnum.APPROVE.getStatus().equals(purchaseRequest.getStatus())) {
            throw exception(PURCHASE_REQUEST_NOT_APPROVE);
        }
        // 2. 校验是否已生成订单
        if (purchaseRequest.getOrderId() != null) {
            throw exception(PURCHASE_REQUEST_ORDER_EXISTS);
        }
        // 3. 校验供应商
        supplierService.validateSupplier(supplierId);

        // 4. 获取申请明细
        List<ErpPurchaseRequestItemDO> requestItems = purchaseRequestItemMapper.selectListByRequestId(id);
        if (CollUtil.isEmpty(requestItems)) {
            throw exception(PURCHASE_REQUEST_NOT_EXISTS);
        }

        // 5. 生成采购订单号
        String orderNo = noRedisDAO.generate(ErpNoRedisDAO.PURCHASE_ORDER_NO_PREFIX);
        if (purchaseOrderMapper.selectByNo(orderNo) != null) {
            throw exception(PURCHASE_ORDER_NO_EXISTS);
        }

        // 6. 创建采购订单
        ErpPurchaseOrderDO purchaseOrder = new ErpPurchaseOrderDO();
        purchaseOrder.setNo(orderNo);
        purchaseOrder.setStatus(ErpAuditStatus.APPROVE.getStatus()); // 采购订单直接为已审核状态
        purchaseOrder.setSupplierId(supplierId);
        purchaseOrder.setOrderTime(purchaseRequest.getRequestTime());
        purchaseOrder.setTotalCount(purchaseRequest.getTotalCount());
        purchaseOrder.setTotalPrice(purchaseRequest.getTotalPrice());
        purchaseOrder.setTotalProductPrice(purchaseRequest.getTotalProductPrice());
        purchaseOrder.setTotalTaxPrice(purchaseRequest.getTotalTaxPrice());
        purchaseOrder.setDiscountPercent(purchaseRequest.getDiscountPercent());
        purchaseOrder.setDiscountPrice(purchaseRequest.getDiscountPrice());
        purchaseOrder.setRemark(purchaseRequest.getRemark());
        purchaseOrder.setInCount(BigDecimal.ZERO);
        purchaseOrder.setInStatus(0);
        purchaseOrderMapper.insert(purchaseOrder);

        // 7. 创建采购订单明细
        List<ErpPurchaseOrderItemDO> orderItems = convertList(requestItems, item -> {
            ErpPurchaseOrderItemDO orderItem = new ErpPurchaseOrderItemDO();
            orderItem.setOrderId(purchaseOrder.getId());
            orderItem.setProductId(item.getProductId());
            orderItem.setProductUnitId(item.getProductUnitId());
            orderItem.setProductPrice(item.getProductPrice());
            orderItem.setCount(item.getCount());
            orderItem.setTotalPrice(item.getTotalPrice());
            orderItem.setTaxPercent(item.getTaxPercent());
            orderItem.setTaxPrice(item.getTaxPrice());
            orderItem.setRemark(item.getRemark());
            orderItem.setInCount(BigDecimal.ZERO);
            orderItem.setQcCheckFlag(false); // 默认不需要质检
            return orderItem;
        });
        purchaseOrderItemMapper.insertBatch(orderItems);

        // 8. 更新采购申请的订单信息
        purchaseRequestMapper.updateById(new ErpPurchaseRequestDO()
                .setId(id)
                .setOrderId(purchaseOrder.getId())
                .setOrderNo(orderNo));

        return purchaseOrder.getId();
    }

    /**
     * 校验采购申请审批分类和流程定义是否存在
     */
    private void validatePurchaseRequestApproveCategoryAndProcessDefinition() {
        List<BpmCategoryDO> categories = bpmCategoryService.getCategoryListByCode(
                Collections.singletonList(PURCHASE_REQUEST_APPROVE_CATEGORY_CODE));
        if (CollUtil.isEmpty(categories)) {
            throw exception(PURCHASE_REQUEST_BPM_CATEGORY_NOT_EXISTS);
        }
    }

    /**
     * 转换 BPM 审批结果为状态
     */
    private Integer convertBpmResultToStatus(Integer bpmResult) {
        if (BpmTaskStatusEnum.APPROVE.getStatus().equals(bpmResult)) {
            return ErpPurchaseRequestStatusEnum.APPROVE.getStatus();
        } else if (BpmTaskStatusEnum.REJECT.getStatus().equals(bpmResult)) {
            return ErpPurchaseRequestStatusEnum.REJECT.getStatus();
        } else if (BpmTaskStatusEnum.CANCEL.getStatus().equals(bpmResult)) {
            return ErpPurchaseRequestStatusEnum.CANCEL.getStatus();
        }
        return null;
    }

    private ErpPurchaseRequestDO validatePurchaseRequestExists(Long id) {
        ErpPurchaseRequestDO purchaseRequest = purchaseRequestMapper.selectById(id);
        if (purchaseRequest == null) {
            throw exception(PURCHASE_REQUEST_NOT_EXISTS);
        }
        return purchaseRequest;
    }

    private ErpPurchaseRequestDO validatePurchaseRequestExistsAndDraft(Long id) {
        ErpPurchaseRequestDO purchaseRequest = validatePurchaseRequestExists(id);
        if (!ErpPurchaseRequestStatusEnum.DRAFT.getStatus().equals(purchaseRequest.getStatus())) {
            throw exception(PURCHASE_REQUEST_UPDATE_FAIL_NOT_DRAFT, purchaseRequest.getNo());
        }
        return purchaseRequest;
    }

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

}