export declare const DEFAULT_TRANSCRIPT_MOUNT_ROWS = 120;
export declare const DEFAULT_TRANSCRIPT_WINDOW_OVERLAP = 64;
export interface TranscriptMountWindow {
    readonly start: number;
    readonly end: number;
    readonly olderCount: number;
    readonly newerCount: number;
}
export declare function resolveTranscriptMountWindow(totalItems: number, requestedStart: number | undefined, size?: number): TranscriptMountWindow;
export declare function transcriptWindowStartForItem(totalItems: number, itemIndex: number, size?: number): number;
export declare function shiftTranscriptWindowStart(totalItems: number, currentStart: number, direction: "older" | "newer", size?: number, overlap?: number): number;
export interface TranscriptScrollIntent {
    readonly nextScrollTop: number;
    readonly leaveTail: boolean;
    readonly reachedOlderEdge: boolean;
    readonly reachedNewerEdge: boolean;
    readonly atBottom: boolean;
}
export declare function resolveTranscriptScrollIntent(scrollTop: number, maxScrollTop: number, delta: number): TranscriptScrollIntent;
export declare function shouldPinTranscriptBottom(input: {
    readonly following: boolean;
    readonly pointerGestureActive: boolean;
    readonly forced: boolean;
}): boolean;