import { SpectrumElement } from '../../element/index.js';
import { DropEffect, DropzoneSize } from './Dropzone.types.js';
declare const DropzoneBase_base: typeof SpectrumElement & {
    new (...args: any[]): import('../../mixins/index.js').SizedElementInterface;
    prototype: import('../../mixins/index.js').SizedElementInterface;
} & import('../../mixins/index.js').SizedElementConstructor;
/**
 * Base class for the `<swc-dropzone>` drop zone component.
 *
 * Encapsulates all drag-and-drop event handling, state management, and
 * validation logic. Rendering, ARIA, and CSS are provided by the concrete
 * SWC subclass.
 *
 * @attribute {DropzoneSize} size - Controls the illustrated icon scale and container dimensions.
 *
 * @slot - Slot for the illustrated message and browse control. Hidden automatically when `filled` is true.
 * @slot filled-content - Slot for the uploaded-state content (e.g. an image preview). Shown automatically when `filled` is true; hidden otherwise.
 *
 * @fires swc-dropzone-should-accept - Cancelable event fired on every native `dragover`
 *   tick while a drag is over the zone, not just on entry. Cancel to reject the dragged
 *   payload and set the cursor to `none`.
 * @fires swc-dropzone-dragover - Fired once when dragged files enter the zone and are
 *   accepted; does not repeat on subsequent `dragover` ticks while still hovering.
 * @fires swc-dropzone-dragleave - Fired when an accepted drag leaves the zone after a
 *   100 ms debounce, or immediately when it becomes rejected. Detail is a plain snapshot
 *   `{ clientX, clientY, relatedTarget }` captured synchronously from the native event.
 * @fires swc-dropzone-drop - Fired when files are dropped on the zone. `element.dragged`
 *   is still `true` when this event fires; it transitions to `false` after dispatch.
 */
export declare abstract class DropzoneBase extends DropzoneBase_base {
    /**
     * The size of the drop zone.
     *
     * @default m
     */
    size: DropzoneSize;
    /**
     * Whether files are currently being dragged over the drop zone.
     * Set automatically by the component; also settable to reflect programmatic state.
     *
     * @attr dragged
     * @default false
     */
    dragged: boolean;
    /**
     * Whether the drop zone has received a file and is in the filled state.
     * Set by consuming code after a successful drop or browse-file selection to
     * switch the zone to its filled visual.
     *
     * @attr filled
     * @default false
     */
    filled: boolean;
    /**
     * The OS drag-cursor feedback shown while a file is held over the zone.
     * Maps directly to `DataTransfer.dropEffect`. Settable via the `drop-effect`
     * attribute, but property changes do not reflect back to the attribute
     * because it controls browser chrome, not component state.
     *
     * @attr drop-effect
     * @type {'copy' | 'move' | 'link' | 'none'}
     * @default 'copy'
     */
    get dropEffect(): DropEffect;
    set dropEffect(value: DropEffect | null);
    /** @internal */
    private _dropEffect;
    protected constructor();
    /** @internal */
    private readonly _sizePropagation;
    /** @internal */
    protected handleDefaultSlotChange(): void;
}
export {};