import { PropertyValues } from 'lit';
import { SlotPresenceController } from '../../controllers/slot-presence-controller/index.js';
import { SpectrumElement } from '../../element/index.js';
import { AccordionHeadingLevel, AccordionSize } from './Accordion.types.js';
/**
 * Base class for accordion item components. Manages open/disabled state,
 * heading level (set by the parent accordion), and the toggle event.
 *
 * @attribute {boolean} open - Whether the accordion item panel is expanded.
 * @attribute {boolean} disabled - Whether the accordion item is disabled.
 * @attribute {AccordionSize} size - Size of the item. Inherited from the parent
 *   accordion when slotted; controls the chevron icon when used standalone.
 *
 * @slot label - The heading text for this accordion item.
 * @slot actions - Optional actions rendered adjacent to the heading, outside
 *   the toggle button so they remain independently interactive.
 * @slot - The panel content revealed when the item is open.
 */
export declare abstract class AccordionItemBase extends SpectrumElement {
    /**
     * Observes whether content is slotted into `[slot="actions"]` so the header
     * can conditionally render the actions container.
     *
     * @internal
     */
    protected slotPresence: SlotPresenceController;
    /**
     * Whether the accordion item panel is expanded.
     */
    get open(): boolean;
    set open(value: boolean);
    /**
     * Whether the accordion item is disabled. A disabled item keeps its header
     * in the tab order but blocks toggling.
     */
    disabled: boolean;
    /**
     * The size of the item. Inherited from the parent accordion; controls which
     * chevron icon is displayed. Has no effect when the item is used standalone.
     */
    size?: AccordionSize;
    private _open;
    /**
     * @internal
     * Heading level (2–6) propagated by the parent accordion. Defaults to 3
     * for standalone items.
     */
    protected headingLevel: AccordionHeadingLevel;
    /**
     * @internal
     * Set by the parent accordion when its own `disabled` is true. Causes the
     * item to render as disabled (aria-disabled + inert panel) without clobbering
     * the item's own `disabled` property, so the per-item state is preserved
     * when the accordion is re-enabled.
     */
    protected parentDisabled: boolean;
    /**
     * @internal
     * Whether content is slotted into `[slot="actions"]`. Consumed by the
     * concrete element's `render()` to conditionally render the actions
     * container.
     */
    protected get hasActions(): boolean;
    /**
     * @internal
     * Whether the item may change `open` (expand or collapse). When false, the
     * `open` setter and `toggle()` leave state unchanged.
     */
    protected mayExpand(): boolean;
    private get contentPanel();
    private dispatchAfterEvent;
    private afterEventPending;
    private readonly handleTransitionEnd;
    private readonly handleTransitionCancel;
    /**
     * @internal
     * Toggles the item open state. Guards for disabled, flips `open`, dispatches
     * the toggle event, and reverts if the event is canceled. On success, dispatches
     * `swc-after-open` or `swc-after-close` after the panel height transition ends,
     * or immediately if no transition is active.
     */
    protected toggle(): void;
    /**
     * @internal
     * Synchronizes parent-managed heading level onto the item.
     */
    setManagedHeading(heading: AccordionHeadingLevel): void;
    /**
     * @internal
     * Synchronizes parent-managed disabled state onto the item.
     */
    setManagedParentDisabled(disabled: boolean): void;
    protected firstUpdated(changedProperties: PropertyValues): void;
    connectedCallback(): void;
    disconnectedCallback(): void;
}