import { type Comment } from '@pantheon-systems/css-client';
export interface ThreadCommentsState {
    /**
     * Oldest first. Empty until the thread arrives. An agent the latest comment mentions
     * is shown as working until it speaks for itself, or as failed once it has taken too
     * long to start.
     */
    comments: readonly Comment[];
    /** The thread is being asked for and nothing has come back yet. */
    loading: boolean;
    /** The thread could not be read, so the comments are unknown rather than absent. */
    failed: boolean;
    /** Ask for the thread again. */
    retry: () => void;
}
/**
 * Whether the thread is waiting on an agent: one has said it is working, or the latest
 * comment mentions one and nothing has come back yet. Nothing pushes changes into the
 * canvas, so while this holds the thread is asked for again on a short clock. Both
 * conditions run out, so a turn that never finished does not keep the thread polling.
 */
export declare function awaitingAgent(comments: readonly Comment[], now: number): boolean;
/**
 * Loads one thread's comments while the reader has it open.
 *
 * Nothing is asked for without a thread id, so a context nobody has commented on costs
 * no request, and a host can pass `undefined` to stand down while the view is closed.
 * Like the triggers, this may be mounted outside the editor's providers, so it reads the
 * query cache directly and answers "nothing" wherever there is nothing to read from.
 */
export declare function useThreadComments(threadId: string | undefined): ThreadCommentsState;