package com.imutil.service.impl;

import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.imutil.entity.CrossTenantAudit;
import com.imutil.entity.CrossTenantGrant;
import com.imutil.mapper.CrossTenantAuditMapper;
import com.imutil.mapper.CrossTenantGrantMapper;
import com.imutil.service.CrossTenantService;
import lombok.extern.slf4j.Slf4j;
import org.noear.solon.annotation.Component;
import org.noear.solon.annotation.Inject;

import java.time.OffsetDateTime;

/**
 * 跨租户通讯授权服务实现
 * <p>
 * 授权匹配：正向(from→to) 优先，未命中再查反向双向(to→from 且 direction=1)。
 * user 字段 NULL 表示通配；permissions 用 LIKE 匹配是否含 send_msg。
 *
 * @author imutil
 */
@Slf4j
@Component
public class CrossTenantServiceImpl implements CrossTenantService {

    private static final String PERM_SEND_MSG = "send_msg";

    @Inject
    private CrossTenantGrantMapper grantMapper;

    @Inject
    private CrossTenantAuditMapper auditMapper;

    @Override
    public Long checkSendMsgGrant(String fromTenant, String fromUser, String toTenant, String toUser) {
        // 同租户或任一租户缺失，不算跨租户通讯
        if (fromTenant == null || toTenant == null || fromTenant.equals(toTenant)) {
            return null;
        }
        // 1. 正向授权 from→to
        Long gid = matchDirected(fromTenant, fromUser, toTenant, toUser, false);
        if (gid != null) {
            return gid;
        }
        // 2. 反向双向授权：记录方向为 to→from 且 direction=1
        return matchDirected(toTenant, toUser, fromTenant, fromUser, true);
    }

    @Override
    public void audit(Long grantId, String msgKey, String fromUser, String toUser) {
        try {
            CrossTenantAudit a = new CrossTenantAudit();
            a.setGrantId(grantId);
            a.setMsgKey(msgKey);
            a.setFromImUserId(fromUser);
            a.setToImUserId(toUser);
            a.setActionTime(OffsetDateTime.now());
            auditMapper.insert(a);
        } catch (Exception e) {
            // 审计写入失败不阻塞主流程
            log.warn("跨租户审计写入失败 grant={} msgKey={} : {}", grantId, msgKey, e.getMessage());
        }
    }

    /**
     * 按指定方向匹配一条 send_msg 授权
     *
     * @param matchFromTenant 查询条件 from_tenant
     * @param matchFromUser   查询条件 from_im_user（NULL 通配由 SQL 处理）
     * @param matchToTenant   查询条件 to_tenant
     * @param matchToUser     查询条件 to_im_user
     * @param now             当前时间（校验有效期）
     * @param requireBidir    是否要求 direction=1（反向匹配时）
     * @return 命中的 grantId，未命中返回 null
     */
    private Long matchDirected(String matchFromTenant, String matchFromUser,
                               String matchToTenant, String matchToUser,
                               boolean requireBidir) {
        CrossTenantGrant g = grantMapper.selectOne(Wrappers.<CrossTenantGrant>lambdaQuery()
                .eq(CrossTenantGrant::getFromTenantId, matchFromTenant)
                .eq(CrossTenantGrant::getToTenantId, matchToTenant)
                .eq(CrossTenantGrant::getStatus, 1)
                .eq(requireBidir, CrossTenantGrant::getDirection, 1)
                .like(CrossTenantGrant::getPermissions, PERM_SEND_MSG)
                .and(w -> w.isNull(CrossTenantGrant::getStartAt).or().apply("start_at <= now()"))
                .and(w -> w.isNull(CrossTenantGrant::getEndAt).or().apply("end_at >= now()"))
                .and(w -> w.isNull(CrossTenantGrant::getFromImUserId).or().eq(CrossTenantGrant::getFromImUserId, matchFromUser))
                .and(w -> w.isNull(CrossTenantGrant::getToImUserId).or().eq(CrossTenantGrant::getToImUserId, matchToUser))
                .last("LIMIT 1"));
        return g == null ? null : g.getGrantId();
    }
}