import { SerialParser } from '../types/index.js';
export interface PacketLengthOptions {
    /** Delimiter byte that marks the start of a packet. Defaults to `0xAA`. */
    delimiter?: number;
    /** Total overhead bytes in the packet (delimiter + length field(s) + any footer). Defaults to `2`. */
    packetOverhead?: number;
    /** Number of consecutive bytes that encode the payload length. Defaults to `1`. */
    lengthBytes?: number;
    /** Byte offset from the delimiter to the first length byte. Defaults to `1`. */
    lengthOffset?: number;
    /** Maximum allowed payload length. Packets exceeding this are discarded. Defaults to `0xFF`. */
    maxLen?: number;
}
/**
 * Creates a packet-length parser that buffers bytes, locates the delimiter,
 * reads the embedded length field, and emits complete packets as `Uint8Array`.
 *
 * @param options - Configuration options.
 * @returns A {@link SerialParser} that emits `Uint8Array` values.
 *
 * @example
 * ```ts
 * import { AbstractSerialDevice, packetLength } from 'webserial-core';
 *
 * // Packets: [0xBC][0x00][len0][len1][cargo...][footer0][footer1]
 * class MyDevice extends AbstractSerialDevice<Uint8Array> {
 *   constructor() {
 *     super({
 *       baudRate: 115200,
 *       parser: packetLength({ delimiter: 0xbc, packetOverhead: 5, lengthBytes: 2, lengthOffset: 2 }),
 *     });
 *   }
 * }
 * ```
 */
export declare function packetLength(options?: PacketLengthOptions): SerialParser<Uint8Array>;