import { ILogger } from "@node-lightning/logger";
import { IWireMessage } from "../messages/IWireMessage";
import { IPeer } from "../Peer";
/**
 * Interface for the sub-system for handling the gossip message relay,
 * also known as rumor mongering.This system is responsible for
 * periodically flushing messages to connected peers and makes a best
 * effort to not send message that have already been sent to a peer.
 *
 * The idea of rumor mongering is that a piece of information is hot. A
 * node attempts to infect connected peers with this information by
 * sending it to them. Once it has been sent, we no longer need to
 * infect them with information.
 */
export interface IGossipRelay {
    /**
     * The current state of gossip relay
     */
    state: GossipRelayState;
    /**
     * Starts gossip relay
     */
    start(): void;
    /**
     * Stops gossip relay
     */
    stop(): void;
    /**
     * Adds a new peer to relay messages to
     * @param peer
     */
    addPeer(peer: IPeer): void;
    /**
     * Removes the peer from relay
     * @param peer
     */
    removePeer(peer: IPeer): void;
    /**
     * Enqueues a message to be broadcast to peers
     * @param msg
     */
    enqueue(msg: IWireMessage): void;
}
/**
 * The state of a IGossipRelay rumor mongerer
 */
export declare enum GossipRelayState {
    /**
     * Rumor mongering is not active
     */
    Inactive = 0,
    /**
     * Rumor mongering is active
     */
    Active = 1
}
/**
 * This is a basic implementation of IGossipRelay that enques all
 * messages and maintaining an index of each peer in the queue. When
 * messages are flushed, only messages that haven't been sent to a peer
 * are sent and the index position for that peer is updated. When the
 * queue of messages has reached a maximum length, older messages are
 * pruned and the index positions are updated.
 */
export declare class GossipRelay {
    readonly logger: ILogger;
    readonly relayPeriodMs: number;
    readonly maxQueueLen: number;
    private _queue;
    private _peers;
    private _timer;
    private _state;
    constructor(logger: ILogger, relayPeriodMs?: number, maxQueueLen?: number);
    /**
     * Gets the current state of gossip relay
     */
    get state(): GossipRelayState;
    /**
     * Starts relay to peers. This enables messages to be enqueued and
     * periodically sent to the peers.
     */
    start(): void;
    /**
     * Stops relay to peers.
     */
    stop(): void;
    /**
     * Adds a new peer to relay messages to
     * @param peer
     */
    addPeer(peer: IPeer): void;
    /**
     * Removes the peer from relay
     * @param peer
     */
    removePeer(peer: IPeer): void;
    /**
     * Enqueues a message to be broadcast to peers.
     * @param msg
     */
    enqueue(msg: IWireMessage): void;
    /**
     * Finds a channel_announcement message based on the short_channel_id
     * @param scid
     */
    private _findChanAnn;
    /**
     * Finds a channel_update message based on the short_channel_id and
     * direction. The found message can then be compared to an inbound
     * message to determine if the new message is newer.
     * @param scid
     * @param direction
     */
    private _findChanUpd;
    /**
     * Finds a node_announcement message based on the node_id. The
     * returned message can be compared to newer messages using the
     * timestamp.
     * @param nodeId
     */
    private _findNodeAnn;
    /**
     * Fires when the timer ticks and will flush messages to peers and
     * prune the queue
     */
    private _onTimer;
    /**
     * Flushes message to a peer based on the index of messages that
     * the peer has received.
     * @param peer
     */
    private _flushToPeer;
    /**
     * Prunes excess message
     */
    private _pruneQueue;
}