36 lines
1.3 KiB
TypeScript
36 lines
1.3 KiB
TypeScript
const bufferPx = 150
|
|
const observer = new IntersectionObserver(entries => {
|
|
for (const entry of entries) {
|
|
const slug = entry.target.id
|
|
const tocEntryElement = document.querySelector(`a[data-for="${slug}"]`)
|
|
const windowHeight = entry.rootBounds?.height
|
|
if (windowHeight && tocEntryElement) {
|
|
if (entry.boundingClientRect.y < windowHeight) {
|
|
tocEntryElement.classList.add("in-view")
|
|
} else {
|
|
tocEntryElement.classList.remove("in-view")
|
|
}
|
|
}
|
|
}
|
|
})
|
|
|
|
function toggleCollapsible(this: HTMLElement) {
|
|
this.classList.toggle("collapsed")
|
|
const content = this.nextElementSibling as HTMLElement
|
|
content.classList.toggle("collapsed")
|
|
content.style.maxHeight = content.style.maxHeight === "0px" ? content.scrollHeight + "px" : "0px"
|
|
}
|
|
|
|
document.addEventListener("nav", () => {
|
|
const toc = document.getElementById("toc")!
|
|
const content = toc.nextElementSibling as HTMLElement
|
|
content.style.maxHeight = content.scrollHeight + "px"
|
|
toc.removeEventListener("click", toggleCollapsible)
|
|
toc.addEventListener("click", toggleCollapsible)
|
|
|
|
// update toc entry highlighting
|
|
observer.disconnect()
|
|
const headers = document.querySelectorAll("h1[id], h2[id], h3[id], h4[id], h5[id], h6[id]")
|
|
headers.forEach(header => observer.observe(header))
|
|
})
|