import { TemplateResult, CSSResultArray } from 'lit';
import NileElement from '../../internal/nile-element';
import '../../nile-input/index';
import '../../nile-button/index';
/**
 * Floating image insert/edit panel, matching nile-rich-text-editor's image
 * dialog: URL + alt + caption (nile-input) and an Insert action. When
 * `upload-from-computer` is set it also offers an "or / Upload from computer"
 * button (with max-size validation), matching the RTE's `uploadfromcomputer`
 * flag. An edit mode pre-fills the fields and adds Remove.
 *
 * The host positions it and listens for:
 *  - `wysiwyg-image-apply`  detail: { src, alt, caption }         (insert / edit)
 *  - `wysiwyg-image-file`   detail: { file, alt, caption }        (upload)
 *  - `wysiwyg-image-remove`                                       (delete active image)
 *  - `wysiwyg-image-cancel`                                       (Escape)
 */
export declare class NileWysiwygImagePanel extends NileElement {
    open: boolean;
    /** True when editing an already-inserted image (shows Remove, "Save"). */
    editing: boolean;
    /** Shows the "Upload from computer" button below the URL field. */
    uploadFromComputer: boolean;
    /** Maximum allowed upload size in bytes (default 2 MB). */
    maxFileSize: number;
    private srcValue;
    private altValue;
    private captionValue;
    private uploadedFileName;
    private errorMessage;
    /** File staged by "Upload from computer", applied on Insert. */
    private stagedFile;
    static get styles(): CSSResultArray;
    focusInput(): void;
    /** Clears every field and returns to insert (non-editing) mode. */
    reset(): void;
    /** Pre-fills the panel for editing an existing image. */
    prefill(data: {
        src?: string;
        alt?: string;
        caption?: string;
    }): void;
    private onSrc;
    private onAlt;
    private onCaption;
    private triggerFilePicker;
    private onFileChange;
    private handleSubmit;
    private handleKeydown;
    render(): TemplateResult;
}
declare global {
    interface HTMLElementTagNameMap {
        'nile-wysiwyg-image-panel': NileWysiwygImagePanel;
    }
}