/**
 * Size of the batch header in bytes.
 * Layout: u64 (partitionId) + u64 (baseOffset) + u64 (baseTimestamp) +
 * u64 (originTimestamp) + u64 (batchLength) + u64 (batchChecksum) +
 * u32 (messageCount) + zero padding up to 256 bytes.
 */
export declare const BATCH_HEADER_SIZE = 256;
/**
 * Size of the per-message frame header in bytes.
 * Layout: u64 (checksum) + u128 (id) + u32 (offsetDelta) +
 * u32 (timestampDelta) + u32 (userHeadersLength) + u32 (payloadLength) +
 * u64 (reserved).
 */
export declare const FRAME_HEADER_SIZE = 48;
/**
 * Batch header describing a run of message frames.
 */
export type BatchHeader = {
    /** Partition the batch belongs to (zero when sent by a client) */
    partitionId: bigint;
    /** Offset of the first message in the batch (zero when sent by a client) */
    baseOffset: bigint;
    /** Server timestamp of the batch in microseconds (zero when sent by a client) */
    baseTimestamp: bigint;
    /** Smallest origin timestamp of the batched messages in microseconds */
    originTimestamp: bigint;
    /** Total batch size in bytes, header included */
    batchLength: bigint;
    /** XXH3-64 checksum of the batch header fields and frame checksums */
    batchChecksum: bigint;
    /** Number of message frames in the batch */
    messageCount: number;
};
/**
 * Per-message frame header.
 */
export type FrameHeader = {
    /** XXH3-64 checksum of the frame past this field, payload and user headers included */
    checksum: bigint;
    /** Unique message identifier */
    id: bigint;
    /** Index of the message within the batch */
    offsetDelta: number;
    /** Message origin timestamp minus batch origin timestamp in microseconds */
    timestampDelta: number;
    /** Length of user-defined headers in bytes */
    userHeadersLength: number;
    /** Length of message payload in bytes */
    payloadLength: number;
    /** Reserved for future use, must be zero */
    reserved: bigint;
};
/**
 * Serializes a batch header to its 256-byte wire format.
 *
 * @param header - Batch header to serialize
 * @returns Serialized batch header buffer
 */
export declare const serializeBatchHeader: (header: BatchHeader) => Buffer;
/**
 * Deserializes a batch header from a buffer.
 *
 * @param b - Buffer containing the serialized batch header
 * @param pos - Starting position in the buffer
 * @returns Parsed BatchHeader object
 */
export declare const deserializeBatchHeader: (b: Buffer, pos?: number) => BatchHeader;
/**
 * Deserializes a frame header from a buffer.
 *
 * @param b - Buffer containing the serialized frame header
 * @param pos - Starting position in the buffer
 * @returns Parsed FrameHeader object
 */
export declare const deserializeFrameHeader: (b: Buffer, pos?: number) => FrameHeader;
/**
 * Computes the XXH3-64 checksum of a complete frame.
 * Covers everything past the checksum field: the remaining frame header,
 * the payload, and the user headers.
 *
 * @param frame - Complete frame buffer [header][payload][user headers]
 * @returns Frame checksum
 */
export declare const frameChecksum: (frame: Buffer) => bigint;
/**
 * Computes the XXH3-64 checksum of a batch.
 * Covers the batch header fields up to the checksum, the message count,
 * and each frame checksum in message order.
 *
 * @param header - Batch header fields, batchChecksum ignored
 * @param frameChecksums - Frame checksums in message order
 * @returns Batch checksum
 */
export declare const batchChecksum: (header: Omit<BatchHeader, "batchChecksum" | "messageCount">, frameChecksums: bigint[]) => bigint;
/**
 * Iggy message header containing metadata for each polled message.
 */
export type IggyMessageHeader = {
    /** Message checksum for integrity verification */
    checksum: bigint;
    /** Unique message identifier (UUID or numeric) */
    id: string | bigint;
    /** Message offset within the partition */
    offset: bigint;
    /** Server-assigned timestamp */
    timestamp: Date;
    /** Client-provided origin timestamp */
    originTimestamp: Date;
    /** Length of user-defined headers in bytes */
    userHeadersLength: number;
    /** Length of message payload in bytes */
    payloadLength: number;
    /** Reserved for future use */
    reserved: bigint;
};
/**
 * Deserializes a message ID from a 16-byte buffer to BigInt.
 *
 * @param b - 16-byte buffer containing the message ID
 * @returns Message ID as BigInt
 */
export declare const deserialiseMessageId: (b: Buffer) => bigint;
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