package com.baiyue.eventbridge.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.baiyue.eventbridge.domain.BridgeInbox;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import java.util.List;

/**
 * 入站事件持久化映射。
 */
@Mapper
public interface BridgeInboxMapper extends BaseMapper<BridgeInbox> {
    @Select("""
            SELECT event_id FROM bridge_inbox
            WHERE ((status IN ('RECEIVED','RETRY') AND (next_retry_at IS NULL OR next_retry_at <= CURRENT_TIMESTAMP(3)))
                OR (status = 'PROCESSING' AND lease_until < CURRENT_TIMESTAMP(3)))
            ORDER BY received_at LIMIT #{limit}
            """)
    List<String> dispatchCandidates(@Param("limit") int limit);

    @Update("""
            UPDATE bridge_inbox SET status='PROCESSING', lease_owner=#{owner},
              lease_until=DATE_ADD(CURRENT_TIMESTAMP(3), INTERVAL #{leaseSeconds} SECOND)
            WHERE event_id=#{eventId}
              AND ((status IN ('RECEIVED','RETRY') AND (next_retry_at IS NULL OR next_retry_at <= CURRENT_TIMESTAMP(3)))
                OR (status='PROCESSING' AND lease_until < CURRENT_TIMESTAMP(3)))
            """)
    int claim(@Param("eventId") String eventId, @Param("owner") String owner,
              @Param("leaseSeconds") long leaseSeconds);

    @Update("""
            UPDATE bridge_inbox SET status='PROCESSED', processed_at=CURRENT_TIMESTAMP(3),
              lease_owner=NULL, lease_until=NULL, next_retry_at=NULL, last_error=NULL
            WHERE event_id=#{eventId} AND status='PROCESSING' AND lease_owner=#{owner}
            """)
    int markProcessed(@Param("eventId") String eventId, @Param("owner") String owner);

    @Update("""
            UPDATE bridge_inbox SET retry_count=retry_count+1,
              status=CASE WHEN retry_count+1 >= #{maxAttempts} THEN 'DEAD' ELSE 'RETRY' END,
              next_retry_at=CASE WHEN retry_count+1 >= #{maxAttempts} THEN NULL
                ELSE DATE_ADD(CURRENT_TIMESTAMP(3), INTERVAL #{backoffSeconds} SECOND) END,
              lease_owner=NULL, lease_until=NULL, last_error=#{error}
            WHERE event_id=#{eventId} AND status='PROCESSING' AND lease_owner=#{owner}
            """)
    int markFailed(@Param("eventId") String eventId, @Param("owner") String owner,
                   @Param("maxAttempts") int maxAttempts,
                   @Param("backoffSeconds") long backoffSeconds, @Param("error") String error);

    @Select("SELECT COALESCE(MAX(attempt_no), 0) + 1 FROM bridge_delivery_attempt WHERE event_id=#{eventId}")
    int nextAttemptNo(@Param("eventId") String eventId);

    @Update("""
            UPDATE bridge_inbox SET status='RETRY', retry_count=0, next_retry_at=CURRENT_TIMESTAMP(3),
              lease_owner=NULL, lease_until=NULL, last_error=#{reason}
            WHERE event_id=#{eventId} AND status='DEAD'
            """)
    int replayDead(@Param("eventId") String eventId, @Param("reason") String reason);
}