import * as http from 'http';
import { WebSocketServer } from 'ws';
import { type CaptureCodec } from './capture-file.js';
export declare const RECORD_STREAM_PATH = "/api/dev/record-stream";
export declare const FRAME_HEADER_BYTES = 4;
/** Sanity bounds on a start request — nothing a real recorder sends is refused. */
export declare const MAX_FRAME_DIMENSION = 8192;
export interface StreamStart {
    recordingName: string;
    width: number;
    height: number;
    /** Absent for raw RGBA frames. */
    codec?: CaptureCodec;
}
export interface StreamError {
    error: string;
}
/** Validate the `start` message. */
export declare function parseStreamStart(raw: unknown): StreamStart | StreamError;
/** Split a binary message into its frame index and pixel bytes; null when it is not a frame. */
export declare function parseFrameMessage(data: Buffer, frameBytes: number): {
    frameIndex: number;
    pixels: Buffer;
} | null;
/**
 * Keeps the raw encoder's input contiguous. The encoder numbers frames sequentially from 0, so the
 * frame written Nth becomes `_00000N.png`; feeding it exactly one frame per index — the real one
 * when it arrived, the previous one when it did not — is what keeps the files aligned with the
 * recorder's own frame count (the trailer's clock).
 */
export declare class FrameSequencer {
    private expected;
    private previous;
    readonly missing: number[];
    /** The buffers to hand to the encoder for this arrival, in order. Empty for a duplicate/late frame. */
    accept(frameIndex: number, pixels: Buffer): Buffer[];
    /** Pad up to the recorder's declared count at stop, so the sequence ends where the timeline says. */
    finish(frameCount: number): Buffer[];
    get written(): number;
}
/**
 * Raw path ffmpeg arguments: RGBA on stdin, one PNG per frame at `<dir>/<name>_%06d.png`, numbered
 * from 0 — the image2 muxer's own default is 1, which would put frame 0 in `_000001.png` while
 * every reader in `cli/src/trailer/` looks for `_000000.png`.
 */
export declare function encoderArgs(start: StreamStart, dir: string): string[];
/**
 * Mount the sink on the sidecar's HTTP server. One session per socket; a second `start` on the
 * same socket is refused. Every failure is reported to the client as `{type:'error'}` so the
 * recorder can fall back to the HTTP sink rather than lose the recording.
 */
export declare function attachRecordingStream(server: http.Server, root: string, log: (line: string) => void, ffmpegBinary?: string): WebSocketServer;