@primer/react/dist/live-region/Announce.js

An implementation of GitHub's Primer Design System using React

import { useEffectOnce } from "../internal/hooks/useEffectOnce.js";
import { useEffectCallback } from "../internal/hooks/useEffectCallback.js";
import { c } from "react-compiler-runtime";
import { jsx } from "react/jsx-runtime";
import { useEffect, useRef } from "react";
import { announceFromElement } from "@primer/live-region-element";
//#region src/live-region/Announce.tsx
/**
* `Announce` is a component that will announce the text content of the
* `children` passed in to screen readers using the given politeness level. It
* will also announce any changes to the text content of `children`
*/
function Announce(props) {
	const $ = c(24);
	let children;
	let delayMs;
	let rest;
	let t0;
	let t1;
	let t2;
	let t3;
	if ($[0] !== props) {
		({as: t0, announceOnShow: t1, children, delayMs, hidden: t2, politeness: t3, ...rest} = props);
		$[0] = props;
		$[1] = children;
		$[2] = delayMs;
		$[3] = rest;
		$[4] = t0;
		$[5] = t1;
		$[6] = t2;
		$[7] = t3;
	} else {
		children = $[1];
		delayMs = $[2];
		rest = $[3];
		t0 = $[4];
		t1 = $[5];
		t2 = $[6];
		t3 = $[7];
	}
	const BaseComponent = t0 === void 0 ? "div" : t0;
	const announceOnShow = t1 === void 0 ? true : t1;
	const hidden = t2 === void 0 ? false : t2;
	const politeness = t3 === void 0 ? "polite" : t3;
	const ref = useRef(null);
	const previousAnnouncementText = useRef(null);
	const savedAnnouncement = useRef(null);
	let t4;
	if ($[8] !== delayMs || $[9] !== hidden || $[10] !== politeness) {
		t4 = () => {
			var _savedAnnouncement$cu;
			const { current: element } = ref;
			if (!element) return;
			if (hidden) return;
			const textContent = getTextContent(element);
			if (!textContent) return;
			if (textContent === previousAnnouncementText.current) return;
			if (!isVisible(element)) return;
			(_savedAnnouncement$cu = savedAnnouncement.current) === null || _savedAnnouncement$cu === void 0 || _savedAnnouncement$cu.cancel();
			savedAnnouncement.current = announceFromElement(element, politeness === "assertive" ? { politeness } : {
				politeness,
				delayMs
			});
			previousAnnouncementText.current = textContent;
		};
		$[8] = delayMs;
		$[9] = hidden;
		$[10] = politeness;
		$[11] = t4;
	} else t4 = $[11];
	const announce = useEffectCallback(t4);
	let t5;
	if ($[12] !== announce || $[13] !== announceOnShow) {
		t5 = () => {
			if (announceOnShow) announce();
		};
		$[12] = announce;
		$[13] = announceOnShow;
		$[14] = t5;
	} else t5 = $[14];
	useEffectOnce(t5);
	let t6;
	let t7;
	if ($[15] !== announce) {
		t6 = () => {
			const { current: container } = ref;
			if (container === null) return;
			const observer = new MutationObserver(() => {
				announce();
			});
			observer.observe(container, {
				subtree: true,
				childList: true,
				characterData: true
			});
			return () => {
				observer.disconnect();
			};
		};
		t7 = [announce];
		$[15] = announce;
		$[16] = t6;
		$[17] = t7;
	} else {
		t6 = $[16];
		t7 = $[17];
	}
	useEffect(t6, t7);
	let t8;
	let t9;
	if ($[18] === Symbol.for("react.memo_cache_sentinel")) {
		t8 = () => () => {
			if (savedAnnouncement.current !== null) {
				savedAnnouncement.current.cancel();
				savedAnnouncement.current = null;
			}
		};
		t9 = [];
		$[18] = t8;
		$[19] = t9;
	} else {
		t8 = $[18];
		t9 = $[19];
	}
	useEffect(t8, t9);
	let t10;
	if ($[20] !== BaseComponent || $[21] !== children || $[22] !== rest) {
		t10 = /*#__PURE__*/ jsx(BaseComponent, {
			...rest,
			ref,
			children
		});
		$[20] = BaseComponent;
		$[21] = children;
		$[22] = rest;
		$[23] = t10;
	} else t10 = $[23];
	return t10;
}
function getTextContent(element) {
	let value = "";
	if (element.hasAttribute("aria-label")) value = element.getAttribute("aria-label");
	else if (element.textContent) value = element.textContent;
	return value ? value.trim() : "";
}
/**
* Determine if an element is visible (not hidden via `display: none` or
* `visibility: hidden`). Prefers the native `checkVisibility()` API when
* available and falls back to `getComputedStyle` for older browsers.
*/
function isVisible(element) {
	if (typeof element.checkVisibility === "function") return element.checkVisibility({
		visibilityProperty: true,
		checkVisibilityCSS: true
	});
	const style = window.getComputedStyle(element);
	return style.display !== "none" && style.visibility !== "hidden";
}
//#endregion
export { Announce };