/**
 * `application/vnd.amazon.eventstream` decoder.
 *
 * Wire format (all integers big-endian):
 *
 *   [total length     u32]
 *   [headers length   u32]
 *   [prelude CRC32    u32]   <- CRC over the first 8 bytes
 *   [headers          headers_length]
 *   [payload          total_length - headers_length - 16]
 *   [message CRC32    u32]   <- CRC over the entire message minus the trailing 4 bytes
 *
 * Headers: a sequence of `[name_len u8][name utf8][value_type u8][value …]`.
 * We only need the typed values Bedrock emits (boolean true/false, byte, short,
 * integer, long, byte-array, string, timestamp, uuid). All are surfaced as
 * strings for ease of consumption — Bedrock only sets string-valued headers in
 * practice (`:event-type`, `:message-type`, `:content-type`, `:exception-type`).
 */
export interface EventStreamMessage {
    /** Lower-cased copy is *not* applied — Bedrock uses casing like `:event-type` verbatim. */
    headers: Record<string, string>;
    payload: Uint8Array;
}
/** CRC32 (IEEE / zlib polynomial 0xEDB88320), matches `@aws-crypto/crc32`. */
export declare function crc32(bytes: Uint8Array): number;
/**
 * Decode a single, fully buffered eventstream message. Throws if the framing is
 * malformed or either CRC mismatches. Used by both `decodeEventStream` (the
 * streaming entry point) and the unit tests, which exercise it with hand-built
 * frames.
 */
export declare function decodeMessage(frame: Uint8Array): EventStreamMessage;
/**
 * Async generator that consumes a `ReadableStream<Uint8Array>` (e.g. a fetch
 * response body) and yields fully-framed messages. Handles arbitrary chunk
 * boundaries: messages may span multiple chunks, and a single chunk may carry
 * many messages.
 */
export declare function decodeEventStream(source: ReadableStream<Uint8Array>): AsyncGenerator<EventStreamMessage>;