/**
 * manage loading of content like svg files.
 * allow to manage the loading only if the container is visible (lazy mode).
 * put data into cache.
 * allow validators on the received content (if sanitize mode enabled).
 *
 * @example
 * ```typescript
 * const lazy = true;
 * const svgLoadContent = new OdsLoadContent([
 *   (content) => {return content !== 'forbiddenText' ? content : 'filtered' }
 * ]);
 *
 * this.svgLoadContent.waitUntilVisible(yourHTMLElement, '50px', () => {
 *   svgLoadContent.load('my/file/path.svg', true, true);
 * }, lazy);
 * ```
 *
 * ---
 *
 * Code inspired by ionic-icons (version 6.0.3) from Ionic team
 * https://github.com/ionic-team/ionicons
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2015-present Ionic (http://ionic.io/)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
export declare class OdsLoadContent {
    private contentCache;
    private contentValidators;
    private io?;
    private readonly logger;
    private requestCache;
    constructor(contentValidators?: Array<(content: string) => string>);
    /**
     * load a given url only in case of element is visible in browser.
     * check first the cache and if not yet cached, make the call and cache it.
     * the cached content can be sanitized with the validators.
     * @param url - url of the content to load
     * @param isVisible - is the element to display is visible in browser
     * @param sanitize - clean content with your own validators
     * @param isBrowser - browser context or not
     */
    load(url: string, isVisible: boolean, sanitize?: boolean, isBrowser?: boolean): Promise<string | undefined>;
    onDestroy(): void;
    /**
     * wait for calling a callback only when the element is visible in the browser, for lazy mode.
     * if lazy not enabled, it calls directly the callback.
     * an intersection observer is used in order to allow the detection.
     * if the browser does not support it, the lazy mode is not applied.
     * @param el - html element to check visibility
     * @param rootMargin - margin trigger on the viewport border used to detect visibility
     * @param cb - callback to call when visible
     * @param lazy - enable or not the lazy mode
     * @param isBrowser - is browser context or not
     */
    waitUntilVisible(el: HTMLElement, rootMargin: string, cb: () => void, lazy: boolean, isBrowser?: boolean): void;
    /**
     * get the cached content of url or fetch it.
     * requests are also cached in order to not doing multiple times the same.
     * @param url - url to fetch if needed
     * @param sanitize - apply validators on the retrieved content or not
     */
    private getContent;
    private sanitize;
}