import { type Component } from '@earendil-works/pi-tui';
import type { CondensedHistoryMode } from '../../../types.js';
/** A message from the broker snapshot, structurally. */
type Message = {
    role?: string;
    customType?: string;
};
export declare function isCycleDivider(message: Message): boolean;
/** Does this message survive condensation into the frozen block? */
export declare function keepWhenCondensed(message: Message, mode: CondensedHistoryMode): boolean;
/**
 * Index into `messages` at which the LIVE (fully rendered) region begins.
 *
 * The snapshot is `[cycle 0][divider][cycle 1][divider]…[current cycle]`, so a
 * transcript with D dividers holds D+1 cycles. Keeping the trailing
 * `liveCycles` of them means everything up to and including divider
 * `D - liveCycles` is condensed. Returns 0 — condense nothing — when the node
 * has not yielded often enough to have older cycles, so a fresh or
 * single-yield node renders exactly as it always did.
 */
export declare function liveRegionStart(messages: readonly Message[], liveCycles: number): number;
/**
 * A settled block of pre-rendered transcript lines. Renders in O(1) at the width
 * it was frozen at, and clips (never reflows) when the pane is narrower. Ctrl+O /
 * Ctrl+T do not reach it: it holds no components to expand, only text.
 */
export declare class FrozenHistoryComponent implements Component {
    private readonly lines;
    private readonly frozenWidth;
    /** Last clip result, so a stable narrow pane clips once rather than per frame. */
    private clipped;
    constructor(lines: readonly string[], frozenWidth: number);
    get lineCount(): number;
    /** Nothing to recompute — the block is text, already laid out. */
    invalidate(): void;
    render(width: number): string[];
}
export {};