package jnpf.dmsService;

import jnpf.dmsEntity.download.entity.DmsWenjianXiazaiShenqingDetailEntity;
import jnpf.dmsEntity.download.entity.DmsWenjianXiazaiShenqingEntity;
import jnpf.dmsEntity.download.form.DmsWorkflowDownloadAuthorizeForm;
import jnpf.dmsEntity.download.vo.DmsWorkflowDownloadAuthorizationVO;
import jnpf.dmsEntity.download.vo.DmsWorkflowDownloadFileVO;
import jnpf.dmsEntity.permission.entity.DmsFilePermissionEntity;
import jnpf.dmsIntegration.audit.DmsAuditRequestSignResolver;
import jnpf.dmsMapper.DmsWenjianXiazaiShenqingDetailMapper;
import jnpf.dmsMapper.DmsWenjianXiazaiShenqingMapper;
import jnpf.exception.DataException;
import jnpf.flowable.WorkFlowApi;
import jnpf.flowable.entity.TaskEntity;
import jnpf.flowable.enums.TaskStatusEnum;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.UUID;

@Service
@RequiredArgsConstructor
public class DmsWorkflowDownloadAuthorizationService {
    private static final String SOURCE_PREFIX = "download-request:";

    private final WorkFlowApi workFlowApi;
    private final DmsWenjianXiazaiShenqingMapper requestMapper;
    private final DmsWenjianXiazaiShenqingDetailMapper detailMapper;
    private final DmsWorkflowFileResolutionService fileResolutionService;
    private final DmsPermissionGrantService permissionGrantService;

    @Transactional(rollbackFor = Exception.class)
    public DmsWorkflowDownloadAuthorizationVO authorize(
            String tenantId, DmsWorkflowDownloadAuthorizeForm form, String serviceId) {
        String flowId = requiredText(form.getSourceId(), "流程ID不能为空");
        String taskId = requiredText(form.getTaskId(), "流程任务ID不能为空");
        TaskEntity task = requireApprovedTask(flowId, taskId);
        DmsWenjianXiazaiShenqingEntity request = uniqueRequest(
                requestMapper.selectByFlowForUpdate(tenantId, flowId, taskId));
        if (!TaskStatusEnum.PASSED.getCode().equals(request.getFlowState())) {
            throw new DataException("文件下载申请尚未审批通过");
        }
        if (trimToNull(form.getBizSign()) == null) {
            form.setBizSign(trimToNull(request.getBizSign()));
        }
        String applicantUserId = requiredText(request.getApplicantUserId(), "文件下载申请缺少申请人");
        List<DmsWenjianXiazaiShenqingDetailEntity> details =
                detailMapper.selectByRequestForUpdate(tenantId, request.getId());
        if (details == null || details.isEmpty()) {
            throw new DataException("文件下载申请没有可授权的文件明细");
        }

        List<ResolvedDownloadFile> files = new ArrayList<>(details.size());
        for (DmsWenjianXiazaiShenqingDetailEntity detail : details) {
            files.add(new ResolvedDownloadFile(detail, fileResolutionService.resolve(
                    tenantId, detail.getId(), detail.getFileReferenceId(), detail.getFileNumber(),
                    detail.getFileName(), detail.getVersionLabel())));
        }
        if (files.stream().map(value -> value.file.getFileVersion().getId()).distinct().count() != files.size()) {
            throw new DataException("下载申请包含重复文件版本");
        }
        List<DmsFilePermissionEntity> permissions = new ArrayList<>();
        for (ResolvedDownloadFile file : files) {
            permissions.addAll(permissionGrantService.ensureWorkflowDownloadPermissions(
                    tenantId, SOURCE_PREFIX + request.getId() + ":" + file.detail.getId(),
                    applicantUserId, java.util.Collections.singletonList(file.file.getFileVersion().getId()),
                    DmsDownloadDeadline.resolve(file.detail.getXiazaiShixian(), file.detail.getId()),
                    serviceId, DmsAuditRequestSignResolver.resolve(form)));
        }
        Map<UUID, UUID> permissionIds = new HashMap<>();
        for (DmsFilePermissionEntity permission : permissions) {
            permissionIds.put(permission.getResourceId(), permission.getId());
        }

        DmsWorkflowDownloadAuthorizationVO result = new DmsWorkflowDownloadAuthorizationVO();
        result.setTaskId(taskId);
        result.setFlowState(task.getStatus());
        result.setFlowStatus(TaskStatusEnum.PASSED.getMessage());
        result.setCompleted(Boolean.TRUE);
        result.setApplicantUserId(applicantUserId);
        for (ResolvedDownloadFile file : files) {
            DmsWorkflowDownloadFileVO item = new DmsWorkflowDownloadFileVO();
            item.setRequestDetailId(file.detail.getId());
            item.setBusinessFileId(file.file.getBusinessFile().getId());
            item.setBusinessFileVersionId(file.file.getBusinessVersion().getId());
            item.setDocumentId(file.file.getFileVersion().getDocumentId());
            item.setFileVersionId(file.file.getFileVersion().getId());
            item.setFileName(file.file.getFileVersion().getFileName());
            item.setMimeType(file.file.getFileVersion().getMimeType());
            item.setSizeBytes(file.file.getFileVersion().getSizeBytes());
            item.setPermissionId(permissionIds.get(file.file.getFileVersion().getId()));
            item.setPermanent(Boolean.FALSE);
            result.getFiles().add(item);
        }
        return result;
    }

    private TaskEntity requireApprovedTask(String flowId, String taskId) {
        TaskEntity task = workFlowApi.getInfoSubmit(taskId);
        if (task == null || !taskId.equals(task.getId())) {
            throw new DataException("未找到与taskId匹配的流程任务");
        }
        if (!flowId.equals(task.getFlowId()) && !flowId.equals(task.getTemplateId())) {
            throw new DataException("流程任务不属于指定flowID");
        }
        if (!TaskStatusEnum.PASSED.getCode().equals(task.getStatus())) {
            throw new DataException("流程任务尚未审核通过，不能授予下载权限");
        }
        return task;
    }

    private DmsWenjianXiazaiShenqingEntity uniqueRequest(
            List<DmsWenjianXiazaiShenqingEntity> requests) {
        if (requests == null || requests.isEmpty()) {
            throw new DataException("未找到对应的文件下载申请");
        }
        if (requests.size() != 1) {
            throw new DataException("流程任务关联了多条文件下载申请");
        }
        return requests.get(0);
    }

    private String requiredText(String value, String message) {
        String normalized = trimToNull(value);
        if (normalized == null) {
            throw new DataException(message);
        }
        return normalized;
    }

    private String trimToNull(String value) {
        return value == null || value.trim().isEmpty() ? null : value.trim();
    }

    private static final class ResolvedDownloadFile {
        private final DmsWenjianXiazaiShenqingDetailEntity detail;
        private final DmsWorkflowFileResolutionService.ResolvedFile file;

        private ResolvedDownloadFile(DmsWenjianXiazaiShenqingDetailEntity detail,
                                     DmsWorkflowFileResolutionService.ResolvedFile file) {
            this.detail = detail;
            this.file = file;
        }
    }
}