/**
 * @file Accessibility Enhancer
 * @description A11y improvements including focus management, screen reader
 * announcements, keyboard navigation, and ARIA utilities.
 *
 * Features:
 * - Focus management and trapping
 * - Screen reader announcements
 * - Keyboard navigation helpers
 * - ARIA attribute management
 * - Reduced motion support
 * - Color contrast utilities
 */
/**
 * Announcement priority
 */
export type AnnouncementPriority = 'polite' | 'assertive';
/**
 * Focus trap options
 */
export interface FocusTrapOptions {
    /** Element to trap focus within */
    container: HTMLElement;
    /** Initial focus element */
    initialFocus?: HTMLElement | string;
    /** Final focus element (when trap is released) */
    returnFocus?: HTMLElement | boolean;
    /** Allow escape key to release trap */
    escapeDeactivates?: boolean;
    /** Callback when escape is pressed */
    onEscape?: () => void;
    /** Click outside behavior */
    clickOutsideDeactivates?: boolean;
    /** Callback when clicking outside */
    onClickOutside?: () => void;
}
/**
 * Focus trap controller
 */
export interface FocusTrapController {
    activate: () => void;
    deactivate: () => void;
    pause: () => void;
    resume: () => void;
}
/**
 * Roving tabindex options
 */
export interface RovingTabindexOptions {
    /** Container element */
    container: HTMLElement;
    /** Selector for focusable items */
    itemSelector: string;
    /** Orientation */
    orientation: 'horizontal' | 'vertical' | 'both';
    /** Loop navigation */
    loop?: boolean;
    /** Initial focused index */
    initialIndex?: number;
    /** Callback when item is focused */
    onFocus?: (element: HTMLElement, index: number) => void;
}
/**
 * Skip link options
 */
export interface SkipLinkOptions {
    /** Target element ID */
    targetId: string;
    /** Link text */
    text?: string;
    /** Custom class name */
    className?: string;
}
/**
 * Color contrast result
 */
export interface ContrastResult {
    ratio: number;
    aa: boolean;
    aaLarge: boolean;
    aaa: boolean;
    aaaLarge: boolean;
}
/**
 * Initialize screen reader announcer elements
 */
export declare function initAnnouncer(): void;
/**
 * Announce a message to screen readers
 */
export declare function announce(message: string, priority?: AnnouncementPriority): void;
/**
 * Announce a message assertively (interrupts current speech)
 */
export declare function announceAssertive(message: string): void;
/**
 * Announce route change
 */
export declare function announceRouteChange(pageTitle: string): void;
/**
 * Announce loading state
 */
export declare function announceLoading(isLoading: boolean, context?: string): void;
/**
 * Announce form validation error
 */
export declare function announceError(message: string): void;
/**
 * Announce success message
 */
export declare function announceSuccess(message: string): void;
/**
 * Get all focusable elements within a container
 */
export declare function getFocusableElements(container: HTMLElement): HTMLElement[];
/**
 * Get the first focusable element within a container
 */
export declare function getFirstFocusable(container: HTMLElement): HTMLElement | null;
/**
 * Get the last focusable element within a container
 */
export declare function getLastFocusable(container: HTMLElement): HTMLElement | null;
/**
 * Focus the first focusable element in a container
 */
export declare function focusFirst(container: HTMLElement): boolean;
/**
 * Focus the last focusable element in a container
 */
export declare function focusLast(container: HTMLElement): boolean;
/**
 * Create a focus trap
 */
export declare function createFocusTrap(options: FocusTrapOptions): FocusTrapController;
/**
 * Create a roving tabindex controller
 */
export declare function createRovingTabindex(options: RovingTabindexOptions): {
    init: () => void;
    destroy: () => void;
    setFocusedIndex: (index: number) => void;
};
/**
 * Create a skip link element
 */
export declare function createSkipLink(options: SkipLinkOptions): HTMLAnchorElement;
/**
 * Install default skip links
 */
export declare function installSkipLinks(): void;
/**
 * Set ARIA expanded state
 */
export declare function setExpanded(element: HTMLElement, expanded: boolean, controlledId?: string): void;
/**
 * Set ARIA pressed state (for toggle buttons)
 */
export declare function setPressed(element: HTMLElement, pressed: boolean): void;
/**
 * Set ARIA selected state
 */
export declare function setSelected(element: HTMLElement, selected: boolean): void;
/**
 * Set ARIA busy state
 */
export declare function setBusy(element: HTMLElement, busy: boolean): void;
/**
 * Set ARIA disabled state
 */
export declare function setDisabled(element: HTMLElement, disabled: boolean): void;
/**
 * Set ARIA hidden state
 */
export declare function setHidden(element: HTMLElement, hidden: boolean): void;
export declare function generateAriaId(prefix?: string): string;
/**
 * Check if user prefers reduced motion
 */
export declare function prefersReducedMotion(): boolean;
/**
 * Subscribe to reduced motion preference changes
 */
export declare function onReducedMotionChange(callback: (prefersReduced: boolean) => void): () => void;
/**
 * Get safe animation duration based on user preference
 */
export declare function getSafeAnimationDuration(normalDuration: number, reducedDuration?: number): number;
/**
 * Calculate relative luminance of a color
 */
export declare function getLuminance(r: number, g: number, b: number): number;
/**
 * Calculate contrast ratio between two colors
 */
export declare function getContrastRatio(color1: [number, number, number], color2: [number, number, number]): number;
/**
 * Check if contrast meets WCAG requirements
 */
export declare function checkContrast(foreground: [number, number, number], background: [number, number, number]): ContrastResult;
/**
 * Parse hex color to RGB
 */
export declare function hexToRgb(hex: string): [number, number, number] | null;
export declare const accessibilityStyles = "\n  .sr-only {\n    position: absolute;\n    width: 1px;\n    height: 1px;\n    padding: 0;\n    margin: -1px;\n    overflow: hidden;\n    clip: rect(0, 0, 0, 0);\n    white-space: nowrap;\n    border: 0;\n  }\n\n  .skip-link {\n    position: absolute;\n    top: -40px;\n    left: 0;\n    background: #000;\n    color: #fff;\n    padding: 8px 16px;\n    z-index: 10000;\n    text-decoration: none;\n  }\n\n  .skip-link:focus {\n    top: 0;\n  }\n\n  .skip-links {\n    position: absolute;\n    top: 0;\n    left: 0;\n    z-index: 10000;\n  }\n\n  /* Visible focus styles */\n  :focus-visible {\n    outline: 2px solid #3b82f6;\n    outline-offset: 2px;\n  }\n\n  /* Reduced motion */\n  @media (prefers-reduced-motion: reduce) {\n    *,\n    *::before,\n    *::after {\n      animation-duration: 0.01ms !important;\n      animation-iteration-count: 1 !important;\n      transition-duration: 0.01ms !important;\n      scroll-behavior: auto !important;\n    }\n  }\n";