package cn.iocoder.yudao.module.archive.service.borrow;

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.archive.controller.admin.borrow.vo.ArchiveBorrowPageReqVO;
import cn.iocoder.yudao.module.archive.controller.admin.borrow.vo.ArchiveBorrowReturnReqVO;
import cn.iocoder.yudao.module.archive.controller.admin.borrow.vo.ArchiveBorrowSaveReqVO;
import cn.iocoder.yudao.module.archive.dal.dataobject.borrow.ArchiveBorrowDO;
import cn.iocoder.yudao.module.archive.dal.dataobject.document.ArchiveDocumentDO;
import cn.iocoder.yudao.module.archive.dal.mysql.borrow.ArchiveBorrowMapper;
import cn.iocoder.yudao.module.archive.dal.redis.ArchiveNoRedisDAO;
import cn.iocoder.yudao.module.archive.enums.ArchiveBorrowStatusEnum;
import cn.iocoder.yudao.module.archive.enums.ArchiveDocumentStatusEnum;
import cn.iocoder.yudao.module.archive.service.document.ArchiveDocumentService;
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 com.baomidou.mybatisplus.core.conditions.update.LambdaUpdateWrapper;
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.time.LocalDateTime;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

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

/**
 * 档案借阅单 Service 实现类
 *
 * @author 超级管理员
 */
@Service
@Validated
@Slf4j
public class ArchiveBorrowServiceImpl implements ArchiveBorrowService {

    /** 档案借阅审批的 BPM 流程分类编码 */
    public static final String BORROW_APPROVE_CATEGORY_CODE = "archive_borrow_approve";

    @Resource
    private ArchiveBorrowMapper borrowMapper;

    @Resource
    private ArchiveDocumentService documentService;

    @Resource
    private ArchiveNoRedisDAO archiveNoRedisDAO;

    @Resource
    private BpmProcessInstanceApi processInstanceApi;

    @Resource
    private BpmCategoryService bpmCategoryService;

    @Resource
    private BpmProcessDefinitionService bpmProcessDefinitionService;

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Long createBorrow(ArchiveBorrowSaveReqVO createReqVO) {
        // 1. 校验借阅人、归还期限、档案可借
        validateBorrower(createReqVO.getBorrowerName());
        validateReturnDeadline(createReqVO);
        ArchiveDocumentDO document = validateDocumentBorrowable(createReqVO.getDocumentId(), null);

        // 2. 组装借阅单（档案编号/标题取快照，避免档案改名后历史单据失真）
        ArchiveBorrowDO borrow = BeanUtils.toBean(createReqVO, ArchiveBorrowDO.class);
        borrow.setId(null);
        borrow.setNo(archiveNoRedisDAO.generate(ArchiveNoRedisDAO.BORROW_NO_PREFIX));
        borrow.setDocumentNo(document.getNo());
        borrow.setDocumentTitle(document.getTitle());
        borrow.setStatus(ArchiveBorrowStatusEnum.DRAFT.getStatus());
        borrowMapper.insert(borrow);
        return borrow.getId();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updateBorrow(ArchiveBorrowSaveReqVO updateReqVO) {
        // 1.1 校验借阅单存在且状态允许修改
        ArchiveBorrowDO oldBorrow = validateBorrowExists(updateReqVO.getId());
        if (!ArchiveBorrowStatusEnum.DRAFT.getStatus().equals(oldBorrow.getStatus())
                && !ArchiveBorrowStatusEnum.REJECTED.getStatus().equals(oldBorrow.getStatus())) {
            throw exception(BORROW_UPDATE_FAIL_STATUS, oldBorrow.getNo(),
                    ArchiveBorrowStatusEnum.nameOf(oldBorrow.getStatus()));
        }
        // 1.2 校验借阅人、归还期限、档案可借（排除自身）
        validateBorrower(updateReqVO.getBorrowerName());
        validateReturnDeadline(updateReqVO);
        ArchiveDocumentDO document = validateDocumentBorrowable(updateReqVO.getDocumentId(), updateReqVO.getId());

        // 2. 更新（档案编号/标题刷新为最新快照）
        ArchiveBorrowDO updateObj = BeanUtils.toBean(updateReqVO, ArchiveBorrowDO.class);
        updateObj.setDocumentNo(document.getNo());
        updateObj.setDocumentTitle(document.getTitle());
        borrowMapper.updateById(updateObj);
    }

    @Override
    public void deleteBorrow(Long id) {
        // 1. 校验借阅单存在且为草稿
        ArchiveBorrowDO borrow = validateBorrowExists(id);
        if (!ArchiveBorrowStatusEnum.DRAFT.getStatus().equals(borrow.getStatus())) {
            throw exception(BORROW_DELETE_FAIL_STATUS, borrow.getNo(),
                    ArchiveBorrowStatusEnum.nameOf(borrow.getStatus()));
        }

        borrowMapper.deleteById(id);
    }

    @Override
    public ArchiveBorrowDO getBorrow(Long id) {
        return borrowMapper.selectById(id);
    }

    @Override
    public PageResult<ArchiveBorrowDO> getBorrowPage(ArchiveBorrowPageReqVO reqVO) {
        return borrowMapper.selectPage(reqVO);
    }

    @Override
    public PageResult<ArchiveBorrowDO> getOverdueBorrowPage(ArchiveBorrowPageReqVO reqVO) {
        return borrowMapper.selectOverduePage(reqVO);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void submitBorrow(Long id, String processDefinitionKey) {
        // 1.1 校验借阅单存在且状态允许提交
        ArchiveBorrowDO borrow = validateBorrowExists(id);
        if (!ArchiveBorrowStatusEnum.DRAFT.getStatus().equals(borrow.getStatus())
                && !ArchiveBorrowStatusEnum.REJECTED.getStatus().equals(borrow.getStatus())) {
            throw exception(BORROW_SUBMIT_FAIL_STATUS, borrow.getNo(),
                    ArchiveBorrowStatusEnum.nameOf(borrow.getStatus()));
        }
        // 1.2 校验档案仍可借（提交前二次校验，避免草稿期间被他人借走）
        validateDocumentBorrowable(borrow.getDocumentId(), borrow.getId());
        // 1.3 先解析可用流程：没有已发布流程时直接失败，避免留下无法提交的孤儿草稿
        String definitionKey = resolveProcessDefinitionKey(processDefinitionKey);

        // 2. 发起流程并回写状态
        String processInstanceId = processInstanceApi.createProcessInstance(getLoginUserId(),
                new BpmProcessInstanceCreateReqDTO()
                        .setProcessDefinitionKey(definitionKey)
                        .setBusinessKey(String.valueOf(id)));
        borrowMapper.updateById(new ArchiveBorrowDO()
                .setId(id)
                .setStatus(ArchiveBorrowStatusEnum.APPROVING.getStatus())
                .setProcessInstanceId(processInstanceId)
                // 重新提交时清空上一次的驳回信息
                .setRejectReason("")
                .setRejectTime(null));
    }

    @Override
    public List<Map<String, Object>> getApproveProcessDefinitionList() {
        validateApproveCategory();

        List<BpmProcessDefinitionInfoDO> definitionInfoList =
                bpmProcessDefinitionService.getProcessDefinitionInfoListByCategory(BORROW_APPROVE_CATEGORY_CODE);
        if (CollUtil.isEmpty(definitionInfoList)) {
            return Collections.emptyList();
        }

        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);
            }
        }

        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 returnBorrow(ArchiveBorrowReturnReqVO returnReqVO) {
        // 1. 校验借阅单存在且为借出中
        ArchiveBorrowDO borrow = validateBorrowExists(returnReqVO.getId());
        if (!ArchiveBorrowStatusEnum.BORROWED.getStatus().equals(borrow.getStatus())) {
            throw exception(BORROW_RETURN_FAIL_STATUS, borrow.getNo(),
                    ArchiveBorrowStatusEnum.nameOf(borrow.getStatus()));
        }

        // 2. 条件更新借阅单为已归还，避免并发重复归还
        int rows = borrowMapper.update(null, new LambdaUpdateWrapper<ArchiveBorrowDO>()
                .eq(ArchiveBorrowDO::getId, borrow.getId())
                .eq(ArchiveBorrowDO::getStatus, ArchiveBorrowStatusEnum.BORROWED.getStatus())
                .set(ArchiveBorrowDO::getStatus, ArchiveBorrowStatusEnum.RETURNED.getStatus())
                .set(ArchiveBorrowDO::getReturnTime, LocalDateTime.now())
                .set(ArchiveBorrowDO::getReturnConfirmUserId, getLoginUserId())
                .set(ArchiveBorrowDO::getReturnRemark, returnReqVO.getReturnRemark()));
        if (rows == 0) {
            throw exception(BORROW_RETURN_FAIL_STATUS, borrow.getNo(),
                    ArchiveBorrowStatusEnum.nameOf(borrow.getStatus()));
        }

        // 3. 档案状态回到「在库」
        if (!documentService.updateDocumentStatusToInStock(borrow.getDocumentId())) {
            log.warn("[returnBorrow] 借阅单({}) 归还成功，但档案({}) 状态未从「借出中」更新为「在库」，请人工核对",
                    borrow.getNo(), borrow.getDocumentNo());
        }
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void updateBorrowAuditStatus(Long id, Integer bpmResult, String reason) {
        ArchiveBorrowDO borrow = borrowMapper.selectById(id);
        if (borrow == null) {
            log.warn("[updateBorrowAuditStatus] 借阅单({}) 不存在，忽略 BPM 结果回写", id);
            return;
        }
        if (!ArchiveBorrowStatusEnum.APPROVING.getStatus().equals(borrow.getStatus())) {
            log.warn("[updateBorrowAuditStatus] 借阅单({}) 不处于审批中状态，忽略 BPM 结果回写", borrow.getNo());
            return;
        }

        // 审批通过：档案条件更新为「借出中」；若档案已被他人借出，条件更新失败则整体回滚，避免出现「借阅单已借出但档案未锁定」的脏状态
        if (BpmTaskStatusEnum.APPROVE.getStatus().equals(bpmResult)) {
            if (!documentService.updateDocumentStatusToBorrowed(borrow.getDocumentId())) {
                throw exception(BORROW_DOCUMENT_LOCKED, borrow.getDocumentNo());
            }
            borrowMapper.updateById(new ArchiveBorrowDO()
                    .setId(id)
                    .setStatus(ArchiveBorrowStatusEnum.BORROWED.getStatus())
                    .setApproveTime(LocalDateTime.now()));
            return;
        }

        // 驳回
        if (BpmTaskStatusEnum.REJECT.getStatus().equals(bpmResult)) {
            borrowMapper.updateById(new ArchiveBorrowDO()
                    .setId(id)
                    .setStatus(ArchiveBorrowStatusEnum.REJECTED.getStatus())
                    .setRejectReason(reason)
                    .setRejectTime(LocalDateTime.now()));
            return;
        }

        // 撤回 / 取消：回到草稿，清空流程实例
        borrowMapper.updateById(new ArchiveBorrowDO()
                .setId(id)
                .setStatus(ArchiveBorrowStatusEnum.DRAFT.getStatus())
                .setProcessInstanceId("")
                .setRejectReason("")
                .setRejectTime(null));
    }

    // ==================== 校验逻辑 ====================

    private ArchiveBorrowDO validateBorrowExists(Long id) {
        ArchiveBorrowDO borrow = id != null ? borrowMapper.selectById(id) : null;
        if (borrow == null) {
            throw exception(BORROW_NOT_EXISTS);
        }
        return borrow;
    }

    private void validateBorrower(String borrowerName) {
        if (StrUtil.isBlank(borrowerName)) {
            throw exception(BORROW_BORROWER_REQUIRED);
        }
    }

    private void validateReturnDeadline(ArchiveBorrowSaveReqVO reqVO) {
        if (reqVO.getReturnDeadline() != null && reqVO.getBorrowDate() != null
                && reqVO.getReturnDeadline().isBefore(reqVO.getBorrowDate())) {
            throw exception(BORROW_DEADLINE_BEFORE_DATE, reqVO.getReturnDeadline(), reqVO.getBorrowDate());
        }
    }

    /**
     * 校验档案可借：档案存在、处于在库、且没有未归还的借阅单
     *
     * @param excludeBorrowId 需要排除的借阅单编号（更新 / 重新提交时传自身）
     */
    private ArchiveDocumentDO validateDocumentBorrowable(Long documentId, Long excludeBorrowId) {
        ArchiveDocumentDO document = documentId != null
                ? documentService.getDocumentWithoutPermissionCheck(documentId) : null;
        if (document == null) {
            throw exception(BORROW_DOCUMENT_NOT_EXISTS);
        }
        if (!ArchiveDocumentStatusEnum.IN_STOCK.getStatus().equals(document.getStatus())) {
            throw exception(BORROW_DOCUMENT_NOT_IN_STOCK, document.getNo(),
                    ArchiveDocumentStatusEnum.nameOf(document.getStatus()));
        }
        List<ArchiveBorrowDO> openBorrows = borrowMapper.selectListByDocumentIdAndStatusIn(documentId,
                List.of(ArchiveBorrowStatusEnum.APPROVING.getStatus(), ArchiveBorrowStatusEnum.BORROWED.getStatus()));
        for (ArchiveBorrowDO openBorrow : openBorrows) {
            if (excludeBorrowId != null && excludeBorrowId.equals(openBorrow.getId())) {
                continue;
            }
            throw exception(BORROW_DOCUMENT_ALREADY_BORROWED, document.getNo(), openBorrow.getNo());
        }
        return document;
    }

    private void validateApproveCategory() {
        List<BpmCategoryDO> categories = bpmCategoryService.getCategoryListByCode(
                Collections.singletonList(BORROW_APPROVE_CATEGORY_CODE));
        if (CollUtil.isEmpty(categories)) {
            throw exception(BORROW_BPM_CATEGORY_NOT_EXISTS);
        }
    }

    /** 解析可用的流程定义 key：优先使用前端传入且确实已发布的最新流程，否则取分类下最新已发布流程 */
    private String resolveProcessDefinitionKey(String processDefinitionKey) {
        List<Map<String, Object>> definitionList = getApproveProcessDefinitionList();
        if (CollUtil.isEmpty(definitionList)) {
            throw exception(BORROW_BPM_PROCESS_DEFINITION_NOT_EXISTS);
        }
        if (StrUtil.isNotBlank(processDefinitionKey)) {
            for (Map<String, Object> item : definitionList) {
                if (processDefinitionKey.equals(String.valueOf(item.get("key")))) {
                    return processDefinitionKey;
                }
            }
        }
        return String.valueOf(definitionList.get(0).get("key"));
    }

}