forgejo-federation/web_src/js/markup/anchors.js
Lunny Xiao e8f3efe1da
Fix and rewrite markup anchor processing (#29931)
Fix #29877

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Co-authored-by: silverwind <me@silverwind.io>
(cherry picked from commit 76ec5410510f09b3ea2bfd2602fcb8f3251087b6)
2024-03-26 19:04:26 +01:00

68 lines
2.4 KiB
JavaScript

import {svg} from '../svg.js';
// scroll to anchor while respecting the `user-content` prefix that exists on the target
function scrollToAnchor(encodedId, initial) {
// abort if the browser has already scrolled to another anchor during page load
if (!encodedId || (initial && document.querySelector(':target'))) return;
const id = decodeURIComponent(encodedId);
let el = document.getElementById(`user-content-${id}`);
// check for matching user-generated `a[name]`
if (!el) {
const nameAnchors = document.getElementsByName(`user-content-${id}`);
if (nameAnchors.length) {
el = nameAnchors[0];
}
}
// compat for links with old 'user-content-' prefixed hashes
if (!el && id.startsWith('user-content-')) {
const el = document.getElementById(id);
if (el) el.scrollIntoView();
}
if (el) {
el.scrollIntoView();
}
}
export function initMarkupAnchors() {
const markupEls = document.querySelectorAll('.markup');
if (!markupEls.length) return;
for (const markupEl of markupEls) {
// create link icons for markup headings, the resulting link href will remove `user-content-`
for (const heading of markupEl.querySelectorAll(`:is(h1, h2, h3, h4, h5, h6`)) {
const originalId = heading.id.replace(/^user-content-/, '');
const a = document.createElement('a');
a.classList.add('anchor');
a.setAttribute('href', `#${encodeURIComponent(originalId)}`);
a.innerHTML = svg('octicon-link');
heading.prepend(a);
}
// remove `user-content-` prefix from links so they don't show in url bar when clicked
for (const a of markupEl.querySelectorAll('a[href^="#"]')) {
const href = a.getAttribute('href');
if (!href.startsWith('#user-content-')) continue;
const originalId = href.replace(/^#user-content-/, '');
a.setAttribute('href', `#${originalId}`);
}
// add `user-content-` prefix to user-generated `a[name]` link targets
// TODO: this prefix should be added in backend instead
for (const a of markupEl.querySelectorAll('a[name]')) {
const name = a.getAttribute('name');
if (!name) continue;
a.setAttribute('name', `user-content-${a.name}`);
}
for (const a of markupEl.querySelectorAll('a[href^="#"]')) {
a.addEventListener('click', (e) => {
scrollToAnchor(e.currentTarget.getAttribute('href')?.substring(1), false);
});
}
}
scrollToAnchor(window.location.hash.substring(1), true);
}