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import { katex, KatexOptions } from "../../deps/katex.ts";import splitAtDelimiters from "./splitAtDelimiters.js";
/* Note: optionsCopy is mutated by this method. If it is ever exposed in the * API, we should copy it before mutating. */const renderMathInText = function (    document: Document,    text: string,    optionsCopy: KatexOptions,) {    const data = splitAtDelimiters(text, optionsCopy.delimiters);    if (data.length === 1 && data[0].type === 'text') {        // There is no formula in the text.        // Let's return null which means there is no need to replace        // the current text node with a new one.        return null;    }
    const fragment = document.createDocumentFragment();
    for (let i = 0; i < data.length; i++) {        if (data[i].type === "text") {            fragment.appendChild(document.createTextNode(data[i].data));        } else {            const span = document.createElement("span");            let math = data[i].data;            // Override any display mode defined in the settings with that            // defined by the text itself            optionsCopy.displayMode = data[i].display;            if (optionsCopy.preProcess) {                math = optionsCopy.preProcess(math);            }            const rendered = katex.renderToString(                math,                optionsCopy,            );            const div = document.createElement("div");            div.innerHTML = rendered.trim();
            span.appendChild(div.firstChild!);            fragment.appendChild(span);        }    }
    return fragment;};
function renderElem(elem: Element, optionsCopy: KatexOptions) {    for (let i = 0; i < elem.childNodes.length; i++) {        const childNode = elem.childNodes[i];        if (childNode.nodeType === 3) {            // Text node            let textContentConcat = childNode.textContent || "";            let sibling = childNode.nextSibling;            let nSiblings = 0;            while (sibling && (sibling.nodeType === 3)) {                textContentConcat += sibling.textContent;                sibling = sibling.nextSibling;                nSiblings++;            }            const frag = renderMathInText(                elem.ownerDocument!,                textContentConcat,                optionsCopy,            );            if (frag) {                // Remove extra text nodes                for (let j = 0; j < nSiblings; j++) {                    childNode.nextSibling?.remove();                }                i += frag.childNodes.length - 1;                elem.replaceChild(frag, childNode);            } else {                // If the concatenated text does not contain math                // the siblings will not either                i += nSiblings;            }        } else if (childNode.nodeType === 1) {            // Element node            const el = childNode as Element;            const className = " " + el.className + " ";            const shouldRender = optionsCopy.ignoredTags!.indexOf(                        el.nodeName.toLowerCase(),                    ) === -1 &&                optionsCopy.ignoredClasses!.every(                    (x) => className.indexOf(" " + x + " ") === -1,                );
            if (shouldRender) {                renderElem(el, optionsCopy);            }        }        // Otherwise, it's something else, and ignore it.    }}
export function renderMathInElement(    elem: Element | undefined,    options: KatexOptions,) {    if (!elem) {        throw new Error("No element provided to render");    }
    renderElem(elem, Object.assign({}, options));}