import { BlockHash, Header } from '@dedot/codecs';
import { HexString } from '@dedot/utils';
import type { BlockExplorer, BlockInfo } from '../../types.js';
import type { LegacyClient } from '../LegacyClient.js';
/**
 * @name LegacyBlockExplorer
 * @description Block explorer implementation for LegacyClient using legacy JSON-RPC methods
 * Optimized to share RPC subscriptions across multiple subscribers using Signal pattern
 */
export declare class LegacyBlockExplorer implements BlockExplorer {
    #private;
    constructor(client: LegacyClient<any>);
    /**
     * Convert PinnedBlock to BlockInfo format
     */
    private toBlockInfo;
    /**
     * Fill missing blocks when a gap is detected
     * Fetches and emits all missing blocks between lastNumber and currentNumber
     */
    private fillMissingBlocks;
    /**
     * Start the shared best block subscription if not already active
     */
    private ensureBestBlockSubscription;
    private hasNewRuntime;
    /**
     * Start the shared finalized block subscription if not already active
     */
    private ensureFinalizedBlockSubscription;
    /**
     * Clean up best block subscription when no more listeners
     */
    private cleanupBestBlockSubscription;
    /**
     * Clean up finalized block subscription when no more listeners
     */
    private cleanupFinalizedBlockSubscription;
    private calculateBlockHash;
    /**
     * Get the best block
     */
    best(): Promise<BlockInfo>;
    /**
     * Subscribe to the best block
     * Multiple subscribers will share a single RPC subscription
     * New subscribers immediately receive the current best block if available
     */
    best(callback: (block: BlockInfo) => void): () => void;
    /**
     * Get the finalized block
     */
    finalized(): Promise<BlockInfo>;
    /**
     * Subscribe to the finalized block
     * Multiple subscribers will share a single RPC subscription
     * New subscribers immediately receive the current finalized block if available
     */
    finalized(callback: (block: BlockInfo) => void): () => void;
    /**
     * Get the header of a block by number or hash
     */
    header(hash: BlockHash): Promise<Header>;
    /**
     * Get the body (transactions) of a block by number or hash
     */
    body(hash: BlockHash): Promise<HexString[]>;
}