import { type Writable } from 'svelte/store';
import type { ViewerApi } from '../../core/types/viewer-api';
import type { StoryWithDefaults } from './storyLoader';
import { type NarrationPlayer } from '../narrationPlayer';
import { type StoryPlaybackClock, type StoryPlaybackState } from '../playbackClock.svelte';
import { type TransitionEventMap } from './chapterTransitionOrchestrator';
export type StoryViewerRuntimeState = 'IDLE' | 'LOADING_CHAPTER' | 'PLAYING_NARRATION' | 'PLAYING_MEDIA' | 'PRESENTING_SILENT' | 'TRANSITION_DELAY' | 'PAUSED' | 'ENDED';
type RuntimeDeps = {
    language?: string;
    createNarrationPlayer?: () => NarrationPlayer;
    createPlaybackClock?: () => StoryPlaybackClock;
    now?: () => number;
    setTimeoutFn?: typeof setTimeout;
    clearTimeoutFn?: typeof clearTimeout;
    setIntervalFn?: typeof setInterval;
    clearIntervalFn?: typeof clearInterval;
    requestAnimationFrame?: (callback: FrameRequestCallback) => number;
    cancelAnimationFrame?: (handle: number) => void;
    prefersReducedMotion?: boolean;
    posePaintedTimeoutMs?: number;
    sourceOpenTimeoutMs?: number;
    crossfadeMs?: number;
    onTransitionEvent?: <K extends keyof TransitionEventMap>(event: K, payload: TransitionEventMap[K]) => void;
};
export type StoryViewerRuntime = {
    loadStory: (story: StoryWithDefaults) => Promise<void>;
    loadChapter: (index: number, options?: {
        autoPlay?: boolean;
    }) => Promise<void>;
    play: () => void;
    pause: () => void;
    stop: () => void;
    destroy: () => void;
    getState: () => StoryViewerRuntimeState;
    currentChapterIndex: Writable<number>;
    isLoading: Writable<boolean>;
    playState: Writable<'idle' | 'playing' | 'paused'>;
    playbackState: Writable<StoryPlaybackState>;
    stageFade: Writable<StageFade>;
    getStory: () => StoryWithDefaults | null;
};
/** Target opacity for the story stage, and how long it has to get there. */
export type StageFade = {
    opacity: number;
    durationMs: number;
};
export declare const createStoryViewerRuntime: (viewer: ViewerApi, deps?: RuntimeDeps) => StoryViewerRuntime;
export {};