/**
 * Icon-state mixin — all `apply*` helpers that update button icons, aria-labels,
 * and visual state in response to player events.
 *
 * `buttonState.ts` owns the pure DOM-mutation free functions; this mixin binds
 * them to the plugin's button refs, player, and state bags. It also holds the
 * quality-label resolution logic that requires both player and menu state.
 *
 * Owns: applyVolume, applyMuted, applyMutedIcon, applyPopupMuteIcon, applyRate,
 *       applyAudioIcon, applyQualityIcon, playingQualityLabel,
 *       resolvePlayingQualityIdx, applyFullscreen, applyTheaterIcon,
 *       applySubsIcon, applyMenuSubsIcon, applyPipIcon, applyAspectRatioIcon.
 */
import type { DesktopUiInternals } from '../internals.js';
export declare const iconStateMethods: {
    readonly applyVolume: (this: DesktopUiInternals, level: number) => void;
    readonly applyMuted: (this: DesktopUiInternals, muted: boolean) => void;
    readonly applyMutedIcon: (this: DesktopUiInternals) => void;
    readonly applyPopupMuteIcon: (this: DesktopUiInternals, muted: boolean) => void;
    readonly applyRate: (this: DesktopUiInternals) => void;
    readonly applyAudioIcon: (this: DesktopUiInternals) => void;
    readonly applyQualityIcon: (this: DesktopUiInternals) => void;
    /**
     * Human label for the level the backend is actually playing right now
     * (e.g. "1080p"). Returns `undefined` when no level info is available
     * (before `level-switched` lands, or non-HLS sources).
     */
    readonly playingQualityLabel: (this: DesktopUiInternals) => string | undefined;
    /**
     * The level index the backend is actually playing. Prefers the cached
     * `playingQualityIdx` (updated on `level-switched`), falls back to peeking
     * `backend.currentLevel()` before the first `level-switched` fires.
     * Returns null when no level is known.
     */
    readonly resolvePlayingQualityIdx: (this: DesktopUiInternals) => number | null;
    readonly applyFullscreen: (this: DesktopUiInternals) => void;
    readonly applyTheaterIcon: (this: DesktopUiInternals, active: boolean) => void;
    readonly applySubsIcon: (this: DesktopUiInternals) => void;
    /** Mirror the bottom-bar subtitle on/off state onto the menu category button. */
    readonly applyMenuSubsIcon: (this: DesktopUiInternals) => void;
    readonly applyPipIcon: (this: DesktopUiInternals, active: boolean) => void;
    readonly applyAspectRatioIcon: (this: DesktopUiInternals) => void;
};