package jnpf.dmsService;

import jnpf.base.UserInfo;
import jnpf.dmsEntity.permission.entity.DmsDocumentEntity;
import jnpf.dmsEntity.permission.entity.DmsFileVersionEntity;
import jnpf.dmsEntity.permission.entity.DmsPermissionResourceEntity;
import jnpf.dmsEntity.permission.enums.DmsPermissionAction;
import jnpf.dmsEntity.permission.enums.DmsResourceType;
import jnpf.dmsEntity.storage.entity.DmsFileObjectEntity;
import jnpf.dmsEntity.storage.form.DmsFileRevisionRegisterForm;
import jnpf.dmsEntity.storage.vo.DmsFileUploadVO;
import jnpf.dmsIntegration.audit.DmsAuditAdapter;
import jnpf.dmsMapper.DmsDocumentMapper;
import jnpf.dmsMapper.DmsFileObjectMapper;
import jnpf.dmsMapper.DmsFileVersionMapper;
import jnpf.dmsMapper.DmsPermissionResourceMapper;
import jnpf.dmsMapper.DmsVersionStateMapper;
import jnpf.dmsPermission.DmsCurrentIdentity;
import jnpf.dmsPermission.DmsPermissionError;
import jnpf.dmsPermission.DmsPermissionException;
import lombok.RequiredArgsConstructor;
import org.springframework.dao.DuplicateKeyException;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.Locale;
import java.util.Objects;

@Service
@RequiredArgsConstructor
public class DmsFileRevisionService {
    private static final String SOURCE_PREFIX = "revision:";

    private final DmsCurrentIdentity currentIdentity;
    private final DmsPermissionDecisionService decisionService;
    private final DmsDocumentMapper documentMapper;
    private final DmsFileVersionMapper fileVersionMapper;
    private final DmsPermissionResourceMapper resourceMapper;
    private final DmsFileObjectMapper fileObjectMapper;
    private final DmsVersionStateMapper versionStateMapper;
    private final DmsAuditAdapter auditAdapter;

    @Transactional
    public DmsFileUploadVO register(DmsFileRevisionRegisterForm form, String serviceId) {
        UserInfo user = currentIdentity.requireUser();
        String tenantId = currentIdentity.tenantId(user);
        String sourceId = form.getSourceId().trim();
        decisionService.requireAllowed(DmsResourceType.DOCUMENT, form.getDocumentId(),
                DmsPermissionAction.UPDATE);

        fileObjectMapper.lockSource(tenantId, serviceId, sourceId);
        DmsFileUploadVO existing = fileObjectMapper.selectUploadBySource(tenantId, serviceId, sourceId);
        if (existing != null) {
            validateRetry(existing, form);
            return existing;
        }

        DmsDocumentEntity document = documentMapper.selectByTenantAndIdForUpdate(tenantId,
                form.getDocumentId());
        if (document == null) {
            throw DmsPermissionException.of(DmsPermissionError.RESOURCE_NOT_FOUND, "待修订文件不存在");
        }
        DmsFileVersionEntity current = fileVersionMapper.selectCurrentEffective(tenantId,
                form.getDocumentId());
        if (current == null || !Objects.equals(current.getId(), form.getBaseFileVersionId())) {
            throw DmsPermissionException.of(DmsPermissionError.REVISION_CONFLICT,
                    "待修订版本已不是现行有效版本，请刷新后重试");
        }

        long nextVersionNo = fileVersionMapper.selectNextVersionNo(tenantId, form.getDocumentId());
        try {
            insertFileVersion(form, tenantId, user.getUserId(), nextVersionNo);
            insertRegistry(form, tenantId, serviceId, sourceId);
            insertFileObject(form, tenantId, user.getUserId(), serviceId, sourceId);
            int superseded = versionStateMapper.supersedeCurrent(tenantId, form.getDocumentId(),
                    form.getBaseFileVersionId(), form.getVersionLabel().trim(), user.getUserId());
            if (superseded != 1) {
                throw DmsPermissionException.of(DmsPermissionError.REVISION_CONFLICT,
                        "现行有效版本已发生变化，请刷新后重试");
            }
            versionStateMapper.insertRevisionEffective(tenantId, form.getDocumentId(),
                    form.getBaseFileVersionId(), form.getFileVersionId(), sourceId,
                    form.getRevisionReason().trim(), user.getUserId());
        } catch (DuplicateKeyException exception) {
            throw conflict("修订登记的资源 ID、source_id、版本号、版本标签或对象键已被占用", exception);
        }

        auditAdapter.dataChange("UPDATE", "模拟修订 DMS 文件", "dms_documents",
                form.getDocumentId().toString(),
                "{\"fileVersionId\":\"" + form.getBaseFileVersionId() + "\"}",
                "{\"fileVersionId\":\"" + form.getFileVersionId() + "\",\"versionLabel\":\""
                        + escapeJson(form.getVersionLabel().trim()) + "\"}");
        return fileObjectMapper.selectUploadBySource(tenantId, serviceId, sourceId);
    }

    private void insertFileVersion(DmsFileRevisionRegisterForm form, String tenantId,
                                   String userId, long versionNo) {
        DmsFileVersionEntity version = new DmsFileVersionEntity();
        version.setId(form.getFileVersionId());
        version.setTenantId(tenantId);
        version.setDocumentId(form.getDocumentId());
        version.setVersionNo(versionNo);
        version.setVersionLabel(form.getVersionLabel().trim());
        version.setFileName(form.getFileName().trim());
        version.setMimeType(trimToNull(form.getMimeType()));
        version.setSizeBytes(form.getSizeBytes());
        version.setChecksumSha256(form.getChecksumSha256().toLowerCase(Locale.ROOT));
        version.setPreparedBy(form.getPreparedBy().trim());
        version.setPreparedOn(form.getPreparedOn());
        version.setCreatedBy(userId);
        fileVersionMapper.insert(version);
    }

    private void insertRegistry(DmsFileRevisionRegisterForm form, String tenantId,
                                String serviceId, String sourceId) {
        DmsPermissionResourceEntity registry = new DmsPermissionResourceEntity();
        registry.setId(form.getFileVersionId());
        registry.setTenantId(tenantId);
        registry.setResourceType(DmsResourceType.FILE_VERSION.name());
        registry.setSourceType("SYSTEM");
        registry.setSourceId(SOURCE_PREFIX + sourceId + ":version");
        registry.setRegisteredBy(serviceId);
        resourceMapper.insert(registry);
    }

    private void insertFileObject(DmsFileRevisionRegisterForm form, String tenantId, String userId,
                                  String serviceId, String sourceId) {
        DmsFileObjectEntity object = new DmsFileObjectEntity();
        object.setId(form.getFileObjectId());
        object.setTenantId(tenantId);
        object.setFileVersionId(form.getFileVersionId());
        object.setStoragePlatform(form.getStoragePlatform().trim());
        object.setBucketName(form.getBucketName().trim());
        object.setBasePath(trimToEmpty(form.getBasePath()));
        object.setObjectPath(form.getObjectPath().trim());
        object.setObjectName(form.getObjectName().trim());
        object.setSourceServiceId(serviceId);
        object.setSourceId(sourceId);
        object.setCreatedBy(userId);
        fileObjectMapper.insert(object);
    }

    private void validateRetry(DmsFileUploadVO existing, DmsFileRevisionRegisterForm form) {
        if (!Objects.equals(existing.getDocumentId(), form.getDocumentId())
                || !Objects.equals(existing.getBaseFileVersionId(), form.getBaseFileVersionId())
                || !Objects.equals(existing.getVersionLabel(), form.getVersionLabel().trim())
                || !Objects.equals(existing.getFileName(), form.getFileName().trim())
                || !Objects.equals(existing.getMimeType(), trimToNull(form.getMimeType()))
                || !Objects.equals(existing.getSizeBytes(), form.getSizeBytes())
                || !equalsIgnoreCase(existing.getChecksumSha256(), form.getChecksumSha256())
                || !Objects.equals(existing.getPreparedBy(), form.getPreparedBy().trim())
                || !Objects.equals(existing.getPreparedOn(), form.getPreparedOn())
                || !Objects.equals(existing.getRevisionReason(), form.getRevisionReason().trim())) {
            throw DmsPermissionException.of(DmsPermissionError.IDEMPOTENCY_CONFLICT,
                    "source_id 对应的修订内容与本次请求不一致");
        }
    }

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

    private String trimToEmpty(String value) {
        return value == null ? "" : value.trim();
    }

    private boolean equalsIgnoreCase(String left, String right) {
        return left == null ? right == null : right != null && left.equalsIgnoreCase(right);
    }

    private String escapeJson(String value) {
        return value.replace("\\", "\\\\").replace("\"", "\\\"");
    }

    private DmsPermissionException conflict(String message, Throwable cause) {
        DmsPermissionException exception = DmsPermissionException.of(DmsPermissionError.SOURCE_CONFLICT, message);
        exception.initCause(cause);
        return exception;
    }
}