Cedric Abonnel
24 lines
851 B
JavaScript
24 lines
851 B
JavaScript
(function () {
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var headings = document.querySelectorAll('.post-content h2, .post-content h3');
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var links = document.querySelectorAll('.toc-list a');
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if (!headings.length || !links.length) return;
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var map = {};
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links.forEach(function (a) {
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map[decodeURIComponent(a.getAttribute('href').slice(1))] = a;
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});
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var active = null;
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var observer = new IntersectionObserver(function (entries) {
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entries.forEach(function (entry) {
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if (entry.isIntersecting) {
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if (active) active.classList.remove('toc-active');
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active = map[entry.target.id] || null;
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if (active) active.classList.add('toc-active');
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}
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});
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}, { rootMargin: '-8% 0px -82% 0px', threshold: 0 });
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headings.forEach(function (h) { observer.observe(h); });
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})();
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