import {isDarkTheme} from '../utils.js';
import {makeCodeCopyButton} from './codecopy.js';
import {displayError} from './common.js';
const {mermaidMaxSourceCharacters} = window.config;
// margin removal is for https://github.com/mermaid-js/mermaid/issues/4907
const iframeCss = `:root {color-scheme: normal}
body {margin: 0; padding: 0; overflow: hidden}
#mermaid {display: block; margin: 0 auto}
blockquote, dd, dl, figure, h1, h2, h3, h4, h5, h6, hr, p, pre {margin: 0}`;
export async function renderMermaid() {
const els = document.querySelectorAll('.markup code.language-mermaid');
if (!els.length) return;
const {default: mermaid} = await import(/* webpackChunkName: "mermaid" */'mermaid');
mermaid.initialize({
startOnLoad: false,
theme: isDarkTheme() ? 'dark' : 'neutral',
securityLevel: 'strict',
});
for (const el of els) {
const pre = el.closest('pre');
if (pre.hasAttribute('data-render-done')) continue;
const source = el.textContent;
if (mermaidMaxSourceCharacters >= 0 && source.length > mermaidMaxSourceCharacters) {
displayError(pre, new Error(`Mermaid source of ${source.length} characters exceeds the maximum allowed length of ${mermaidMaxSourceCharacters}.`));
continue;
}
try {
await mermaid.parse(source);
} catch (err) {
displayError(pre, err);
continue;
}
try {
// can't use bindFunctions here because we can't cross the iframe boundary. This
// means js-based interactions won't work but they aren't intended to work either
const {svg} = await mermaid.render('mermaid', source);
const iframe = document.createElement('iframe');
iframe.classList.add('markup-render', 'tw-invisible');
iframe.srcdoc = `${svg}`;
const mermaidBlock = document.createElement('div');
mermaidBlock.classList.add('mermaid-block', 'is-loading', 'tw-hidden');
mermaidBlock.append(iframe);
const btn = makeCodeCopyButton();
btn.setAttribute('data-clipboard-text', source);
mermaidBlock.append(btn);
const updateIframeHeight = () => {
iframe.style.height = `${iframe.contentWindow.document.body.clientHeight}px`;
};
// update height when element's visibility state changes, for example when the diagram is inside
// a + block and the block becomes visible upon user interaction, it
// would initially set a incorrect height and the correct height is set during this callback.
(new IntersectionObserver(() => {
updateIframeHeight();
}, {root: document.documentElement})).observe(iframe);
iframe.addEventListener('load', () => {
pre.replaceWith(mermaidBlock);
mermaidBlock.classList.remove('tw-hidden');
updateIframeHeight();
setTimeout(() => { // avoid flash of iframe background
mermaidBlock.classList.remove('is-loading');
iframe.classList.remove('tw-invisible');
}, 0);
});
document.body.append(mermaidBlock);
} catch (err) {
displayError(pre, err);
}
}
}