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

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.lang.Assert;
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.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.order.ErpPurchaseOrderSaveReqVO;
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.product.ErpProductDO;
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.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.ErpPurchaseRequestStatusEnum;
import cn.iocoder.yudao.module.erp.service.product.ErpProductService;
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
 *
 * @author 芋道源码
 */
@Service
@Validated
@Slf4j
public class ErpPurchaseRequestServiceImpl implements ErpPurchaseRequestService {

    /**
     * 采购申请 BPM 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 ErpNoRedisDAO noRedisDAO;

    @Resource
    private ErpProductService productService;
    @Resource
    private ErpSupplierService supplierService;

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

    @Resource
    private ErpPurchaseOrderService purchaseOrderService;

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Long createPurchaseRequest(ErpPurchaseRequestSaveReqVO createReqVO, Long userId, Long deptId) {
        // 1.1 校验订单项的有效性
        List<ErpPurchaseRequestItemDO> purchaseRequestItems = validatePurchaseRequestItems(createReqVO.getItems());
        // 1.2 生成申请单号，并校验唯一性
        String no = noRedisDAO.generate(ErpNoRedisDAO.PURCHASE_REQUEST_NO_PREFIX);
        if (purchaseRequestMapper.selectByNo(no) != null) {
            throw exception(PURCHASE_REQUEST_NO_EXISTS);
        }

        // 日志：检查部门和用户信息
        log.info("[createPurchaseRequest] 创建采购申请，userId={}, deptId={}", userId, deptId);

        // 2.1 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, purchaseRequestItems);
        purchaseRequestMapper.insert(purchaseRequest);
        // 2.2 插入申请明细
        purchaseRequestItems.forEach(o -> o.setRequestId(purchaseRequest.getId()));
        purchaseRequestItemMapper.insertBatch(purchaseRequestItems);
        return purchaseRequest.getId();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updatePurchaseRequest(ErpPurchaseRequestSaveReqVO updateReqVO) {
        // 1.1 校验存在
        ErpPurchaseRequestDO purchaseRequest = validatePurchaseRequestExists(updateReqVO.getId());
        // 1.2 校验状态，只有草稿状态才能修改
        if (!ErpPurchaseRequestStatusEnum.DRAFT.getStatus().equals(purchaseRequest.getStatus())) {
            throw exception(PURCHASE_REQUEST_UPDATE_FAIL_NOT_DRAFT, purchaseRequest.getNo());
        }
        // 1.3 校验订单项的有效性
        List<ErpPurchaseRequestItemDO> purchaseRequestItems = validatePurchaseRequestItems(updateReqVO.getItems());

        // 2.1 更新申请单
        ErpPurchaseRequestDO updateObj = BeanUtils.toBean(updateReqVO, ErpPurchaseRequestDO.class);
        calculateTotalPrice(updateObj, purchaseRequestItems);
        purchaseRequestMapper.updateById(updateObj);
        // 2.2 更新申请明细
        updatePurchaseRequestItemList(updateReqVO.getId(), purchaseRequestItems);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void deletePurchaseRequest(List<Long> ids) {
        // 1. 校验不处于非草稿状态
        List<ErpPurchaseRequestDO> purchaseRequests = purchaseRequestMapper.selectByIds(ids);
        if (CollUtil.isEmpty(purchaseRequests)) {
            return;
        }
        purchaseRequests.forEach(purchaseRequest -> {
            if (!ErpPurchaseRequestStatusEnum.DRAFT.getStatus().equals(purchaseRequest.getStatus())) {
                throw exception(PURCHASE_REQUEST_DELETE_FAIL_NOT_DRAFT, purchaseRequest.getNo());
            }
        });

        // 2. 遍历删除
        purchaseRequests.forEach(purchaseRequest -> {
            // 2.1 删除申请单
            purchaseRequestMapper.deleteById(purchaseRequest.getId());
            // 2.2 删除申请明细
            purchaseRequestItemMapper.deleteByRequestId(purchaseRequest.getId());
        });
    }

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

    private List<ErpPurchaseRequestItemDO> validatePurchaseRequestItems(List<ErpPurchaseRequestSaveReqVO.Item> list) {
        // 1. 校验产品存在
        List<ErpProductDO> productList = productService.validProductList(
                convertSet(list, ErpPurchaseRequestSaveReqVO.Item::getProductId));
        Map<Long, ErpProductDO> productMap = convertMap(productList, ErpProductDO::getId);
        // 2. 转化为 ErpPurchaseRequestItemDO 列表
        return convertList(list, o -> BeanUtils.toBean(o, ErpPurchaseRequestItemDO.class, item -> {
            item.setProductUnitId(productMap.get(item.getProductId()).getUnitId());
            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) {
        // 第一步，对比新老数据，获得添加、修改、删除的列表
        List<ErpPurchaseRequestItemDO> oldList = purchaseRequestItemMapper.selectListByRequestId(id);
        List<List<ErpPurchaseRequestItemDO>> diffList = diffList(oldList, newList,
                (oldVal, newVal) -> oldVal.getId().equals(newVal.getId()));

        // 第二步，批量添加、修改、删除
        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));
        }
    }

    private void calculateTotalPrice(ErpPurchaseRequestDO purchaseRequest, List<ErpPurchaseRequestItemDO> items) {
        purchaseRequest.setTotalCount(getSumValue(items, ErpPurchaseRequestItemDO::getCount, BigDecimal::add));
        purchaseRequest.setTotalProductPrice(getSumValue(items, ErpPurchaseRequestItemDO::getTotalPrice, BigDecimal::add, BigDecimal.ZERO));
        purchaseRequest.setTotalTaxPrice(getSumValue(items, 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()));
    }

    @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
    @Transactional(rollbackFor = Exception.class)
    public void submitPurchaseRequest(Long id, String processDefinitionKey, Long userId) {
        // 1. 校验申请单存在且为草稿状态
        ErpPurchaseRequestDO request = validatePurchaseRequestExists(id);
        if (!ErpPurchaseRequestStatusEnum.DRAFT.getStatus().equals(request.getStatus())) {
            throw exception(PURCHASE_REQUEST_SUBMIT_FAIL_NOT_DRAFT);
        }

        // 2. 校验分类和流程定义是否存在
        validatePurchaseRequestApproveCategoryAndProcessDefinition();

        // 3. 校验传入的流程定义 Key 是否属于该分类且处于激活状态
        ProcessDefinition processDefinition = bpmProcessDefinitionService.getActiveProcessDefinition(processDefinitionKey);
        if (processDefinition == null) {
            throw exception(PURCHASE_REQUEST_BPM_PROCESS_DEFINITION_NOT_EXISTS);
        }

        // 4. 创建流程实例（使用用户选择的流程定义 Key）
        String processInstanceId = bpmProcessInstanceApi.createProcessInstance(userId,
                new BpmProcessInstanceCreateReqDTO()
                        .setProcessDefinitionKey(processDefinitionKey)
                        .setBusinessKey(String.valueOf(id)));

        // 5. 更新申请单状态
        purchaseRequestMapper.updateById(new ErpPurchaseRequestDO()
                .setId(id)
                .setProcessInstanceId(processInstanceId)
                .setStatus(ErpPurchaseRequestStatusEnum.PROCESS.getStatus()));
    }

    /**
     * 校验 BPM 采购申请审批分类和流程定义是否存在
     */
    private void validatePurchaseRequestApproveCategoryAndProcessDefinition() {
        // 1. 校验分类是否存在
        List<String> codes = Collections.singletonList(PURCHASE_REQUEST_APPROVE_CATEGORY_CODE);
        Map<String, ?> categoryMap = bpmCategoryService.getCategoryMap(codes);
        if (!categoryMap.containsKey(PURCHASE_REQUEST_APPROVE_CATEGORY_CODE)) {
            throw exception(PURCHASE_REQUEST_BPM_CATEGORY_NOT_EXISTS);
        }

        // 2. 校验分类下是否有可用的流程定义
        List<BpmProcessDefinitionInfoDO> definitionInfoList = bpmProcessDefinitionService
                .getProcessDefinitionInfoListByCategory(PURCHASE_REQUEST_APPROVE_CATEGORY_CODE);
        if (CollUtil.isEmpty(definitionInfoList)) {
            throw exception(PURCHASE_REQUEST_BPM_PROCESS_DEFINITION_NOT_EXISTS);
        }

        // 3. 校验是否有激活状态的流程定义
        Set<String> processDefinitionIds = convertSet(definitionInfoList, BpmProcessDefinitionInfoDO::getProcessDefinitionId);
        List<ProcessDefinition> processDefinitions = bpmProcessDefinitionService.getProcessDefinitionList(processDefinitionIds);
        boolean hasActiveDefinition = processDefinitions.stream()
                .anyMatch(pd -> !pd.isSuspended());
        if (!hasActiveDefinition) {
            throw exception(PURCHASE_REQUEST_BPM_PROCESS_DEFINITION_NOT_EXISTS);
        }
    }

    @Override
    public void updatePurchaseRequestAuditStatus(Long id, Integer bpmResult) {
        // 1. 校验申请单存在且为审批中状态
        ErpPurchaseRequestDO request = validatePurchaseRequestExists(id);
        if (!ErpPurchaseRequestStatusEnum.PROCESS.getStatus().equals(request.getStatus())) {
            log.error("[updatePurchaseRequestAuditStatus] 申请单({}) 不处于审批中", id);
            throw exception(PURCHASE_REQUEST_UPDATE_AUDIT_STATUS_FAIL_NOT_PROCESS);
        }

        // 2. 转换审批结果
        Integer auditStatus = convertBpmResultToAuditStatus(bpmResult);
        purchaseRequestMapper.updateById(new ErpPurchaseRequestDO()
                .setId(id)
                .setStatus(auditStatus));
    }

    /**
     * BPM 审批结果转换
     */
    private Integer convertBpmResultToAuditStatus(Integer bpmResult) {
        Integer auditStatus = BpmTaskStatusEnum.APPROVE.getStatus().equals(bpmResult)
                ? ErpPurchaseRequestStatusEnum.APPROVE.getStatus()
                : BpmTaskStatusEnum.REJECT.getStatus().equals(bpmResult)
                ? ErpPurchaseRequestStatusEnum.REJECT.getStatus()
                : BpmTaskStatusEnum.CANCEL.getStatus().equals(bpmResult)
                ? ErpPurchaseRequestStatusEnum.CANCEL.getStatus() : null;
        Assert.notNull(auditStatus, "BPM 审批结果({}) 转换失败", bpmResult);
        return auditStatus;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Long generatePurchaseOrder(Long id, Long supplierId, Long userId) {
        // 1. 校验申请单存在且已审批通过
        ErpPurchaseRequestDO request = validatePurchaseRequestExists(id);
        if (!ErpPurchaseRequestStatusEnum.APPROVE.getStatus().equals(request.getStatus())) {
            throw exception(PURCHASE_REQUEST_NOT_APPROVE);
        }
        // 校验是否已生成采购订单
        if (request.getOrderId() != null) {
            throw exception(PURCHASE_REQUEST_ORDER_EXISTS);
        }

        // 2. 校验供应商
        supplierService.validateSupplier(supplierId);

        // 3. 获取申请明细
        List<ErpPurchaseRequestItemDO> requestItems = purchaseRequestItemMapper.selectListByRequestId(id);

        // 4. 构建采购订单 VO
        ErpPurchaseOrderSaveReqVO orderVO = new ErpPurchaseOrderSaveReqVO();
        orderVO.setSupplierId(supplierId);
        orderVO.setOrderTime(java.time.LocalDateTime.now());
        orderVO.setRemark("由采购申请单[" + request.getNo() + "]生成");
        // 转换明细项
        orderVO.setItems(convertList(requestItems, item -> {
            ErpPurchaseOrderSaveReqVO.Item orderItem = new ErpPurchaseOrderSaveReqVO.Item();
            orderItem.setProductId(item.getProductId());
            orderItem.setProductUnitId(item.getProductUnitId());
            orderItem.setProductPrice(item.getProductPrice());
            orderItem.setCount(item.getCount());
            orderItem.setTaxPercent(item.getTaxPercent());
            orderItem.setRemark(item.getRemark());
            return orderItem;
        }));

        // 5. 创建采购订单
        Long orderId = purchaseOrderService.createPurchaseOrder(orderVO);

        // 6. 更新申请单关联信息
        purchaseRequestMapper.updateById(new ErpPurchaseRequestDO()
                .setId(id)
                .setOrderId(orderId)
                .setOrderTime(java.time.LocalDateTime.now()));

        return orderId;
    }

    @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);

        // 3. 获取流程定义详情
        Set<String> processDefinitionIds = convertSet(definitionInfoList, BpmProcessDefinitionInfoDO::getProcessDefinitionId);
        List<ProcessDefinition> processDefinitions = bpmProcessDefinitionService.getProcessDefinitionList(processDefinitionIds);

        // 4. 过滤：只保留激活状态，且相同 key 只保留最新版本
        Map<String, ProcessDefinition> latestVersionMap = new HashMap<>();
        for (ProcessDefinition pd : processDefinitions) {
            if (pd.isSuspended()) {
                continue; // 跳过挂起的流程
            }
            ProcessDefinition existing = latestVersionMap.get(pd.getKey());
            if (existing == null || pd.getVersion() > existing.getVersion()) {
                latestVersionMap.put(pd.getKey(), pd);
            }
        }

        // 5. 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());
            item.put("version", pd.getVersion());
            result.add(item);
        }
        return result;
    }

}