package jnpf.bizcommon.audit.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import jnpf.audit.AuditConsts;
import jnpf.bizcommon.audit.entity.AuditEventEntity;
import jnpf.bizcommon.audit.entity.model.AuditEventDetailVO;
import jnpf.bizcommon.audit.entity.model.AuditEventListVO;
import jnpf.bizcommon.audit.entity.model.AuditOperationGroupRow;
import jnpf.bizcommon.audit.entity.model.AuditPageQuery;
import jnpf.bizcommon.audit.mapper.AuditEventMapper;
import jnpf.bizcommon.audit.mapper.AuditQueryMapper;
import jnpf.bizcommon.audit.service.AuditFieldDiffViewService;
import jnpf.bizcommon.audit.service.AuditFormRegistry;
import jnpf.bizcommon.audit.service.AuditQueryService;
import jnpf.bizcommon.audit.service.support.AuditQueryResponseSanitizer;
import jnpf.bizcommon.audit.service.support.AuditEventCategories;
import jnpf.base.vo.PageListVO;
import jnpf.base.vo.PaginationVO;
import jnpf.exception.DataException;
import jnpf.util.JsonUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/** 审计事件查询服务；写入侧完成物理合并，查询侧仅按 operationId 组织展示关系。 */
@Service
public class AuditQueryServiceImpl implements AuditQueryService {

    /** timeline 全量上限（spec：LIMIT 500） */
    private static final int TIMELINE_LIMIT = 500;
    /** 列表只下发前 3 条子表标题 + 总数——保持「列表不含 extra 正文」的敏感面约定。 */
    private static final int LIST_SUB_TITLE_LIMIT = 3;
    /** 分页大小上限（Step 2 契约：强制 pageSize<=100） */
    private static final long MAX_PAGE_SIZE = 100L;
    private static final long DEFAULT_PAGE_SIZE = 20L;

    @Autowired
    private AuditQueryMapper auditQueryMapper;

    @Autowired
    private AuditEventMapper auditEventMapper;

    @Autowired
    private AuditFormRegistry auditFormRegistry;

    @Autowired
    private AuditFieldDiffViewService auditFieldDiffViewService;

    @Override
    public PageListVO<AuditEventListVO> page(AuditPageQuery query) {
        long pageSize = query.getPageSize();
        if (pageSize <= 0) {
            pageSize = DEFAULT_PAGE_SIZE;
        } else if (pageSize > MAX_PAGE_SIZE) {
            pageSize = MAX_PAGE_SIZE;
        }
        long currentPage = query.getCurrentPage();
        if (currentPage <= 0) {
            currentPage = 1L;
        }
        // Codex 批次三a Minor#3：OFFSET 溢出防护——currentPage 传超大值（如 Long.MAX_VALUE）时
        // (currentPage-1)*pageSize 会 long 乘法溢出成负数，拼进 SQL LIMIT/OFFSET 语义未定义。
        // Math.multiplyExact 显式检测溢出，命中则降级为空页（total 仍按条件正常返回，不查明细页）。
        long offset;
        boolean offsetOverflow;
        try {
            offset = Math.multiplyExact(currentPage - 1, pageSize);
            offsetOverflow = false;
        } catch (ArithmeticException ex) {
            offset = 0L;
            offsetOverflow = true;
        }

        QueryWrapper<AuditEventEntity> ew = buildWrapper(query);
        long total = auditQueryMapper.countOperations(ew);
        List<AuditEventListVO> list;
        if (offsetOverflow) {
            list = Collections.emptyList();
        } else {
            List<AuditOperationGroupRow> groups = auditQueryMapper.selectOperationPage(ew, offset, pageSize);
            list = buildOperationRows(groups);
        }

        // 回写生效后的分页参数供返回包装读取（对照 LimsBizLogController：Pagination 承载 total，
        // JsonUtil.getJsonToBean 窄化成 PaginationVO——同一惯例，仅挪到 Service 层以贴合本任务
        // 字面执行的 Controller 签名）
        query.setCurrentPage(currentPage);
        query.setPageSize(pageSize);
        query.setTotal(total);

        PageListVO<AuditEventListVO> vo = new PageListVO<>();
        vo.setList(list);
        vo.setPagination(JsonUtil.getJsonToBean(query, PaginationVO.class));
        return vo;
    }

    @Override
    public AuditEventDetailVO detail(Long id) {
        AuditEventEntity entity = auditEventMapper.selectById(id);
        if (entity == null) {
            throw new DataException("审计事件不存在：id=" + id);
        }
        return toDetailVo(entity);
    }

    @Override
    public List<AuditEventListVO> timeline(String targetId) {
        List<AuditOperationGroupRow> groups = groupRows(
                auditQueryMapper.selectTimeline(targetId, TIMELINE_LIMIT));
        // target_id 只属于业务目标行；签名等关联事件使用自己的 target_id，需按 operation_id 补查。
        return buildOperationRows(groups);
    }

    private List<AuditEventListVO> buildOperationRows(List<AuditOperationGroupRow> groups) {
        if (groups.isEmpty()) {
            return Collections.emptyList();
        }
        List<String> gids = new ArrayList<>(groups.size());
        for (AuditOperationGroupRow group : groups) {
            gids.add(group.getGid());
        }
        return buildOperationRows(groups, auditQueryMapper.selectByOperationGids(gids));
    }

    /** 将已物理合并的事件挂到 BUSINESS 主行；这里不得再次组合 fieldDiffs。 */
    private List<AuditEventListVO> buildOperationRows(List<AuditOperationGroupRow> groups,
                                                      List<AuditEventEntity> events) {
        Map<String, List<AuditEventEntity>> eventsByGid = new LinkedHashMap<>();
        for (AuditEventEntity event : events) {
            String gid = operationGid(event);
            eventsByGid.computeIfAbsent(gid, ignored -> new ArrayList<>()).add(event);
        }

        List<AuditEventListVO> result = new ArrayList<>(groups.size());
        for (AuditOperationGroupRow group : groups) {
            List<AuditEventEntity> related = eventsByGid.get(group.getGid());
            if (related == null) {
                continue;
            }
            AuditEventEntity business = null;
            List<AuditEventListVO> signatures = new ArrayList<>(2);
            for (AuditEventEntity event : related) {
                if (AuditEventCategories.BUSINESS.equals(event.getEventCategory())) {
                    business = event;
                } else if (AuditEventCategories.PRIMARY_SIGN.equals(event.getEventCategory())
                        || AuditEventCategories.REVIEW_SIGN.equals(event.getEventCategory())) {
                    signatures.add(toListVo(event));
                }
            }
            if (business == null) {
                continue;
            }
            AuditEventListVO main = toListVo(business);
            main.setSubEvents(signatures);
            main.setSigned(!signatures.isEmpty());
            result.add(main);
        }
        return result;
    }

    private List<AuditOperationGroupRow> groupRows(List<AuditEventEntity> events) {
        Map<String, AuditOperationGroupRow> groups = new LinkedHashMap<>();
        for (AuditEventEntity event : events) {
            String gid = operationGid(event);
            AuditOperationGroupRow group = groups.get(gid);
            if (group == null) {
                group = new AuditOperationGroupRow();
                group.setGid(gid);
                group.setGrpTime(event.getEventTime());
                groups.put(gid, group);
            }
        }
        return new ArrayList<>(groups.values());
    }

    private String operationGid(AuditEventEntity event) {
        return StringUtils.hasText(event.getOperationId()) ? event.getOperationId() : event.getClientEventId();
    }

    private QueryWrapper<AuditEventEntity> buildWrapper(AuditPageQuery query) {
        QueryWrapper<AuditEventEntity> ew = new QueryWrapper<>();
        if (query.getStartTime() != null) {
            ew.ge("event_time", query.getStartTime());
        }
        if (query.getEndTime() != null) {
            ew.le("event_time", query.getEndTime());
        }
        if (StringUtils.hasText(query.getOperatorName())) {
            ew.like("operator_name", query.getOperatorName());
        }
        if (StringUtils.hasText(query.getAppName())) {
            ew.eq("app_name", query.getAppName());
        }
        // Codex 批次三a Important#1：biz_module 是用户视角的业务应用筛选（app_name 层 0 固定为 jnpf-visualdev）
        if (StringUtils.hasText(query.getBizModule())) {
            ew.eq("biz_module", query.getBizModule());
        }
        if (StringUtils.hasText(query.getEventType())) {
            ew.eq("event_type", query.getEventType());
        }
        if (StringUtils.hasText(query.getActionCode())) {
            ew.eq("action_code", query.getActionCode());
        }
        if (StringUtils.hasText(query.getTargetTable())) {
            ew.eq("target_table", query.getTargetTable());
        }
        if (StringUtils.hasText(query.getBizCode())) {
            ew.eq("biz_code", query.getBizCode());
        }
        if (StringUtils.hasText(query.getBizType())) {
            ew.eq("biz_type", query.getBizType());
        }
        if (StringUtils.hasText(query.getKeyword())) {
            ew.like("field_diffs", query.getKeyword());
        }
        return ew;
    }

    private AuditEventListVO toListVo(AuditEventEntity e) {
        AuditEventListVO vo = new AuditEventListVO();
        vo.setId(e.getId());
        vo.setOperationId(e.getOperationId());
        vo.setClientEventId(e.getClientEventId());
        vo.setEventTime(e.getEventTime());
        vo.setTenantId(e.getTenantId());
        vo.setOperatorId(e.getOperatorId());
        vo.setOperatorName(e.getOperatorName());
        vo.setOperatorOrgId(e.getOperatorOrgId());
        vo.setAppName(e.getAppName());
        vo.setBizModule(e.getBizModule());
        vo.setIp(e.getIp());
        vo.setIpRegion(e.getIpRegion());
        vo.setBrowser(e.getBrowser());
        vo.setOs(e.getOs());
        vo.setRequestUri(e.getRequestUri());
        vo.setEventType(e.getEventType());
        if (AuditEventCategories.REVIEW_SIGN.equals(e.getEventCategory())) {
            vo.setSignatureRole("REVIEW");
        } else if (AuditEventCategories.PRIMARY_SIGN.equals(e.getEventCategory())) {
            vo.setSignatureRole("PRIMARY");
        }
        vo.setActionCode(e.getActionCode());
        vo.setActionLabel(e.getActionLabel());
        vo.setSourceLayer(e.getSourceLayer());
        vo.setTargetTable(e.getTargetTable());
        vo.setTargetId(AuditQueryResponseSanitizer.hidesTargetId(e.getTargetTable())
                ? null : e.getTargetId());
        vo.setBizType(e.getBizType());
        vo.setBizCode(e.getBizCode());
        vo.setDiffCount(computeDiffCount(e.getFieldDiffs()));
        vo.setReason(e.getReason());
        vo.setRecordTitle(e.getRecordTitle());
        vo.setEntryType(e.getEntryType());
        vo.setEntryId(e.getEntryId());
        vo.setEntryName(e.getEntryName());
        vo.setCreatedAt(e.getCreatedAt());
        // 子事件保留自身签名标记；BUSINESS 主行会在组装后按关联签名重新赋值。
        vo.setSigned(AuditConsts.TYPE_E_SIGNATURE.equals(e.getEventType()));
        applySubTitles(vo, e.getExtra());
        return vo;
    }

    /**
     * 从 extra.recordSubTitles 取子表标题行，只下发前 {@link #LIST_SUB_TITLE_LIMIT} 条 + 总数。
     * 不整体下发 extra：正文里除 dataSnapshot 外还有各种来源标记与上下文，列表接口不该带出去。
     */
    @SuppressWarnings("unchecked")
    private void applySubTitles(AuditEventListVO vo, String extraJson) {
        if (!StringUtils.hasText(extraJson)) {
            return;
        }
        try {
            Map<String, Object> extra = JsonUtil.stringToMap(extraJson);
            Object raw = extra == null ? null : extra.get("recordSubTitles");
            if (!(raw instanceof List)) {
                return;
            }
            List<?> all = (List<?>) raw;
            List<String> head = new ArrayList<>();
            for (Object item : all) {
                if (head.size() >= LIST_SUB_TITLE_LIMIT) {
                    break;
                }
                if (item != null) {
                    head.add(String.valueOf(item));
                }
            }
            vo.setSubTitles(head);
            vo.setSubTitleCount(all.size());
        } catch (Throwable ignored) {
            // extra 解析失败不影响列表主行——标题是锦上添花，不能炸掉整页
        }
    }

    private AuditEventDetailVO toDetailVo(AuditEventEntity e) {
        AuditEventDetailVO vo = new AuditEventDetailVO();
        vo.setId(e.getId());
        vo.setClientEventId(e.getClientEventId());
        vo.setOperationId(e.getOperationId());
        vo.setEventTime(e.getEventTime());
        vo.setTenantId(e.getTenantId());
        vo.setOperatorId(e.getOperatorId());
        vo.setOperatorName(e.getOperatorName());
        vo.setOperatorOrgId(e.getOperatorOrgId());
        vo.setAppName(e.getAppName());
        vo.setBizModule(e.getBizModule());
        vo.setIp(e.getIp());
        vo.setIpRegion(e.getIpRegion());
        vo.setBrowser(e.getBrowser());
        vo.setOs(e.getOs());
        vo.setRequestUri(e.getRequestUri());
        vo.setEventType(e.getEventType());
        vo.setActionCode(e.getActionCode());
        vo.setActionLabel(e.getActionLabel());
        vo.setSourceLayer(e.getSourceLayer());
        vo.setTargetTable(e.getTargetTable());
        vo.setTargetId(AuditQueryResponseSanitizer.hidesTargetId(e.getTargetTable())
                ? null : e.getTargetId());
        vo.setBizType(e.getBizType());
        vo.setBizCode(e.getBizCode());
        String modelId = AuditQueryResponseSanitizer.sourceModelId(e.getExtra());
        Map<String, jnpf.audit.diff.AuditFieldDiff.FieldMeta> metadata =
                auditFormRegistry.resolveFieldMetadata(modelId, e.getTargetTable());
        String sanitizedFieldDiffs = AuditQueryResponseSanitizer.sanitizeFieldDiffs(
                e.getFieldDiffs(), metadata);
        vo.setFieldDiffs(sanitizedFieldDiffs);
        vo.setFieldDiffList(auditFieldDiffViewService.build(e, sanitizedFieldDiffs, metadata));
        vo.setExtra(AuditQueryResponseSanitizer.sanitizeJson(e.getExtra()));
        vo.setDataSnapshot(AuditQueryResponseSanitizer.sanitizeJson(e.getDataSnapshot(), metadata));
        vo.setReason(e.getReason());
        vo.setRecordTitle(e.getRecordTitle());
        vo.setEntryType(e.getEntryType());
        vo.setEntryId(e.getEntryId());
        vo.setEntryName(e.getEntryName());
        vo.setPrevHash(e.getPrevHash());
        vo.setCreatedAt(e.getCreatedAt());
        return vo;
    }

    /** field_diffs 是 VisualLogModel[] JSON；空/非法 JSON 一律降级为 0，不让摘要计算炸列表接口。 */
    private Integer computeDiffCount(String fieldDiffs) {
        if (!StringUtils.hasText(fieldDiffs)) {
            return 0;
        }
        return AuditQueryResponseSanitizer.effectiveDiffCount(fieldDiffs);
    }
}