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import { useState, useEffect } from 'react';
function getWindowDimensions() {
const { innerWidth: width, innerHeight: height } = window;
return { width, height };
}
export function useWindowDimensions() {
const [windowDimensions, setWindowDimensions] = useState(getWindowDimensions());
useEffect(() => {
function handleResize() { setWindowDimensions(getWindowDimensions()); }
window.addEventListener('resize', handleResize);
return () => window.removeEventListener('resize', handleResize);
});
return windowDimensions;
}
export function useDebounce(value, delay) {
const [debouncedValue, setDebouncedValue] = useState(value);
useEffect(() => {
const handler = setTimeout(() => setDebouncedValue(value), delay);
return () => clearTimeout(handler);
}, [value, delay]);
return debouncedValue;
}
export function GlobalState(initialValue) {
this.value = initialValue;
this.subscribers = [];
this.getValue = () => this.value;
this.setValue = (newState) => {
if (this.getValue() === newState) return;
this.value = newState;
this.subscribers.forEach(subscriber => subscriber(this.value));
}
this.subscribe = (itemToSubscribe) => {
if (this.subscribers.indexOf(itemToSubscribe) > -1) return
this.subscribers.push(itemToSubscribe);
}
this.unsubscribe = (itemToUnsubscribe) => {
this.subscribers = this.subscribers.filter(subscriber => subscriber !== itemToUnsubscribe);
}
}
export function useGlobalState(globalState) {
const [, setState] = useState();
const state = globalState.getValue();
function reRender(newState) { setState({}); }
useEffect(() => {
globalState.subscribe(reRender);
return () => globalState.unsubscribe(reRender);
})
function setGlobalState(newState) { globalState.setValue(newState); }
return [state, setGlobalState];
}
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