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rOACCT/node_modules/@restart/hooks/cjs/useIntersectionObserver.js
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useIntersectionObserver.js
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"use strict";
exports.__esModule = true;
exports.default = void 0;
var _react = require("react");
var _useStableMemo = _interopRequireDefault(require("./useStableMemo"));
var _useIsomorphicEffect = _interopRequireDefault(require("./useIsomorphicEffect"));
var _useEventCallback = _interopRequireDefault(require("./useEventCallback"));
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
function useIntersectionObserver(element, callbackOrOptions, maybeOptions) {
var callback;
var options;
if (typeof callbackOrOptions === 'function') {
callback = callbackOrOptions;
options = maybeOptions || {};
} else {
options = callbackOrOptions || {};
}
var _options = options,
threshold = _options.threshold,
root = _options.root,
rootMargin = _options.rootMargin;
var _useState = (0, _react.useState)(null),
entries = _useState[0],
setEntry = _useState[1];
var handler = (0, _useEventCallback.default)(callback || setEntry); // We wait for element to exist before constructing
var observer = (0, _useStableMemo.default)(function () {
return root !== null && typeof IntersectionObserver !== 'undefined' && new IntersectionObserver(handler, {
threshold: threshold,
root: root,
rootMargin: rootMargin
});
}, [handler, root, rootMargin, threshold && JSON.stringify(threshold)]);
(0, _useIsomorphicEffect.default)(function () {
if (!element || !observer) return;
observer.observe(element);
return function () {
observer.unobserve(element);
};
}, [observer, element]);
return callback ? undefined : entries || [];
}
var _default = useIntersectionObserver;
exports.default = _default;
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