import type { TurnSummaryStatus } from "./turn-summary-model.js";
import type { ActivityItem, TimelineGroup, ToolCallItem } from "./types.js";
import { type OpenGeniText } from "../messages/runtime.js";
export type ActivityGroup = Extract<TimelineGroup, {
    kind: "activity";
}>;
export type TurnGroup = Extract<TimelineGroup, {
    kind: "turn";
}>;
export declare function durationBetween(startedAt: string, endedAt: string): number | undefined;
/** Compaction landmarks among a fold's groups (secondary summary facet). */
export declare function compactedLandmarkCount(groups: readonly TimelineGroup[]): number;
export declare function clusterIsSettled(group: ActivityGroup): boolean;
export declare function flattenActivityItems(groups: readonly TimelineGroup[]): ActivityItem[];
export type ReadableWorkOptions = {
    /** Host shows startup phases as ordinary details (web: startup-details context). */
    startupDetails: boolean;
    /** Startup chrome was dismissed by the reader. */
    startupDismissed: boolean;
};
/**
 * A readable turn whose only work so far is environment preparation renders as one quiet
 * preparation surface instead of a "Working" fold.
 */
export declare function isPreparingWork(group: ActivityGroup, options: ReadableWorkOptions): boolean;
/**
 * Whether a readable turn's work row has anything to reveal when expanded.
 * Unless the host shows startup phases as details, the work row's rail only
 * renders failed or cancelled preparation steps, so a detail made only of
 * completed or still-running steps (for example the queue phase before a turn
 * was parked on a usage limit) renders nothing and does not make the row
 * expandable.
 */
export declare function readableWorkHasDetails(group: ActivityGroup & {
    work: NonNullable<ActivityGroup["work"]>;
}, options: Pick<ReadableWorkOptions, "startupDetails">): boolean;
/**
 * Status of a readable turn's work row, minus the host-rendered live preview.
 * Time spent waiting for model capacity is not work: the worked duration and
 * the live working clock exclude it, and the wait itself shows no clock. A
 * wait's `detail` is its one quiet secondary line.
 */
export declare function readableWorkStatus(t: OpenGeniText, group: ActivityGroup & {
    work: NonNullable<ActivityGroup["work"]>;
}): Omit<TurnSummaryStatus, "preview"> & {
    detail?: string | undefined;
};
/** Whether a readable turn's work fold starts expanded. */
export declare function readableWorkDefaultOpen(group: ActivityGroup): true | undefined;
/** Whether the live preview should show (images stay primary output instead). */
export declare function readableWorkShowsPreview(group: ActivityGroup): boolean;
/**
 * The step a rolling preview shows: steps advance with event order (progress notes and
 * startup phases have their own surfaces). Mirrors the web RollingActivity selection.
 */
export declare function rollingActivityItem(items: readonly ActivityItem[], previousItem?: ActivityItem, mounted?: boolean): {
    item: ActivityItem;
    running: boolean;
    earlierCount: number;
} | null;
export declare function isToolCall(item: ActivityItem): item is ToolCallItem;