/**
 * Copyright Aquera Inc 2023
 *
 * This source code is licensed under the BSD-3-Clause license found in the
 * LICENSE file in the root directory of this source tree.
 */
import { Marked } from 'marked';
import NileElement from '../internal/nile-element';
import type { CSSResultGroup, PropertyValues, TemplateResult } from 'lit';
/**
 * Nile markdown component.
 *
 * @tag nile-markdown
 */
/**
 * @summary Renders markdown content as HTML in the browser using GitHub Flavored Markdown.
 * @status experimental
 *
 * Content can be provided either through the `value` property or through a
 * `<script type="text/markdown">` element placed as a direct child:
 *
 * ```html
 * <nile-markdown>
 *   <script type="text/markdown">
 *     # Hello
 *     This is **markdown**.
 *   </script>
 * </nile-markdown>
 * ```
 *
 * Leading whitespace common to all lines is stripped, so the markdown can be
 * indented to match the surrounding HTML without rendering as a code block.
 *
 * All instances share a single Marked parser. Use `NileMarkdown.getMarked()`
 * to customize it (extensions, renderers, etc.) and `NileMarkdown.updateAll()`
 * to re-render existing instances after changing the configuration.
 *
 * WARNING: The markdown is converted to HTML without sanitization. Do not
 * render unsanitized user input, as this can expose users to XSS attacks.
 *
 * @event nile-markdown-rendered - Emitted after the markdown has been parsed and rendered.
 *
 * @csspart base - The component's base wrapper containing the rendered HTML.
 */
export declare class NileMarkdown extends NileElement {
    static styles: CSSResultGroup;
    /** The shared Marked instance used by every nile-markdown on the page. */
    private static marked;
    /** All connected instances, used by `updateAll()`. */
    private static instances;
    /**
     * Returns the shared Marked instance so it can be configured with custom
     * options, extensions, or renderers. Changes affect all instances; call
     * `NileMarkdown.updateAll()` afterwards to re-render existing ones.
     */
    static getMarked(): Marked;
    /** Re-renders every connected nile-markdown instance. */
    static updateAll(): void;
    /**
     * The markdown to render. Takes precedence over a
     * `<script type="text/markdown">` child when set.
     */
    value: string;
    /** Number of spaces a tab is converted to during whitespace normalization. */
    tabSize: number;
    private renderedHtml;
    /** Re-renders automatically when the markdown script child changes. */
    private mutationObserver;
    connectedCallback(): void;
    disconnectedCallback(): void;
    protected willUpdate(changed: PropertyValues): void;
    protected updated(changed: PropertyValues): void;
    /** Reads the markdown source from `value` or the script child. */
    private getSource;
    /**
     * Converts tabs to spaces and removes the leading indentation common to all
     * lines, so markdown indented to match the HTML doesn't render as code.
     */
    private normalizeWhitespace;
    /** Parses the markdown source into `renderedHtml`. */
    private computeHtml;
    /** Parses the markdown source and renders the resulting HTML. */
    renderMarkdown(): void;
    render(): TemplateResult;
}
export default NileMarkdown;
declare global {
    interface HTMLElementTagNameMap {
        'nile-markdown': NileMarkdown;
    }
}