import type { Chart, NormalizedChart } from 'modern-idoc';
import type { Element2D } from './Element2D';
import { CoreObject } from '../../../core';
import { CanvasTexture } from '../../resources';
/**
 * Renders an idoc chart with echarts (optional dependency). echarts draws into an
 * offscreen canvas, which is uploaded as a CanvasTexture and drawn directly onto the
 * parent element in `draw()` — the same way fill/background paint a texture, so the
 * chart is the element's own content (no extra child node). Updates are
 * microtask-coalesced. Without echarts installed, charts render nothing (warned once).
 */
export declare class Element2DChart extends CoreObject implements NormalizedChart {
    protected _parent: Element2D;
    enabled: boolean;
    type: NormalizedChart['type'];
    grouping: NormalizedChart['grouping'];
    categories: NormalizedChart['categories'];
    series: NormalizedChart['series'];
    title: NormalizedChart['title'];
    legend: NormalizedChart['legend'];
    categoryAxis: NormalizedChart['categoryAxis'];
    valueAxis: NormalizedChart['valueAxis'];
    protected _instance?: any;
    protected _container?: HTMLElement;
    protected _texture?: CanvasTexture;
    protected _dirty: boolean;
    protected _scheduled: boolean;
    constructor(_parent: Element2D);
    setProperties(properties?: Chart): this;
    protected _updateProperty(key: string, value: any, oldValue: any): void;
    protected _requestUpdate(): void;
    isValid(): boolean;
    /** Render with echarts into the offscreen canvas backing `_texture`. */
    update(): Promise<void>;
    /** echarts 缺失时画一个虚线框 + 文案的占位纹理，而非静默空白。 */
    protected _renderPlaceholder(width: number, height: number): void;
    /** Paint the echarts texture onto the element, like fill/background do. */
    draw(): void;
    /** Map the normalized idoc chart to an echarts option. */
    protected _toOption(): Record<string, any>;
    protected _teardown(): void;
    protected _destroy(): void;
}