import { TemplateResult } from 'lit';
type AlignTo = HTMLElement | string | (() => HTMLElement | null);
type BoundsStrategy = 'element' | 'offsetParent' | 'closest' | 'union';
export interface DropdownPortalOptions {
    alignTo?: AlignTo;
    boundsStrategy?: BoundsStrategy;
    closestSelector?: string;
    unionSelector?: string;
    offset?: {
        x?: number;
        y?: number;
    };
    /** If true, clamp portal to viewport horizontally */
    clampToViewport?: boolean;
    /**
     * The DOM element to append the portal to.
     * - `document.body` (default): portal uses `position: fixed` — escapes overflow containers.
     * - Any other element: portal uses `position: absolute` — respects the container's overflow
     *   and disappears naturally when the trigger scrolls out of view.
     *
     * Use `overflow-strategy="clip"` on `ctt-dropdown-input` to enable auto-detection,
     * or set `portalContainer` directly for deterministic control.
     */
    portalTarget?: HTMLElement;
}
/**
 * Walk up the composed tree (crossing shadow root boundaries via assignedSlot and getRootNode).
 * Required to find overflow ancestors when the component is inside a shadow DOM.
 */
export declare function getComposedParent(node: Node): Node | null;
export interface DropdownPortalRef {
    container: HTMLElement;
    updateContent(newContent: HTMLElement | string | TemplateResult): void;
    updatePosition(): void;
    remove(): void;
}
export declare function createDropdownPortal(id: string, content: HTMLElement | string | TemplateResult, sourceElement: HTMLElement, options?: DropdownPortalOptions): DropdownPortalRef;
/**
 * Position the portal below (or above) the anchor element.
 *
 * Two modes:
 * - **Fixed** (default, `portalTarget` is `document.body`):
 *   Uses viewport coordinates. Flips above if overflowing the viewport bottom.
 *   Clamps horizontally within the viewport.
 *
 * - **Absolute** (`portalTarget` is a specific container):
 *   Uses coordinates relative to the container, accounting for its scroll offset.
 *   No viewport flip — the container's overflow clips the portal naturally,
 *   so the portal disappears when the trigger scrolls out of view.
 */
export declare function updatePortalPosition(id: string, sourceElement: HTMLElement, options?: DropdownPortalOptions): void;
export declare function removeDropdownPortal(id: string): void;
export declare function hasDropdownPortal(id: string): boolean;
export declare function getDropdownPortal(id: string): HTMLElement | null;
export declare function cleanupAllPortals(): void;
export {};