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Diffstat (limited to 'src/utils/react.tsx')
-rw-r--r-- | src/utils/react.tsx | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/src/utils/react.tsx b/src/utils/react.tsx new file mode 100644 index 0000000..69c1df2 --- /dev/null +++ b/src/utils/react.tsx @@ -0,0 +1,128 @@ +/* + * Vencord, a modification for Discord's desktop app + * Copyright (c) 2022 Vendicated and contributors + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. +*/ + +import { React, useEffect, useReducer, useState } from "@webpack/common"; + +import { makeLazy } from "./lazy"; +import { checkIntersecting } from "./misc"; + +/** + * Check if an element is on screen + * @param intersectOnly If `true`, will only update the state when the element comes into view + * @returns [refCallback, isIntersecting] + */ +export const useIntersection = (intersectOnly = false): [ + refCallback: React.RefCallback<Element>, + isIntersecting: boolean, +] => { + const observerRef = React.useRef<IntersectionObserver | null>(null); + const [isIntersecting, setIntersecting] = useState(false); + + const refCallback = (element: Element | null) => { + observerRef.current?.disconnect(); + observerRef.current = null; + + if (!element) return; + + if (checkIntersecting(element)) { + setIntersecting(true); + if (intersectOnly) return; + } + + observerRef.current = new IntersectionObserver(entries => { + for (const entry of entries) { + if (entry.target !== element) continue; + if (entry.isIntersecting && intersectOnly) { + setIntersecting(true); + observerRef.current?.disconnect(); + observerRef.current = null; + } else { + setIntersecting(entry.isIntersecting); + } + } + }); + observerRef.current.observe(element); + }; + + return [refCallback, isIntersecting]; +}; + +type AwaiterRes<T> = [T, any, boolean]; +interface AwaiterOpts<T> { + fallbackValue: T; + deps?: unknown[]; + onError?(e: any): void; +} +/** + * Await a promise + * @param factory Factory + * @param fallbackValue The fallback value that will be used until the promise resolved + * @returns [value, error, isPending] + */ + +export function useAwaiter<T>(factory: () => Promise<T>): AwaiterRes<T | null>; +export function useAwaiter<T>(factory: () => Promise<T>, providedOpts: AwaiterOpts<T>): AwaiterRes<T>; +export function useAwaiter<T>(factory: () => Promise<T>, providedOpts?: AwaiterOpts<T | null>): AwaiterRes<T | null> { + const opts: Required<AwaiterOpts<T | null>> = Object.assign({ + fallbackValue: null, + deps: [], + onError: null, + }, providedOpts); + const [state, setState] = useState({ + value: opts.fallbackValue, + error: null, + pending: true + }); + + useEffect(() => { + let isAlive = true; + if (!state.pending) setState({ ...state, pending: true }); + + factory() + .then(value => isAlive && setState({ value, error: null, pending: false })) + .catch(error => isAlive && (setState({ value: null, error, pending: false }), opts.onError?.(error))); + + return () => void (isAlive = false); + }, opts.deps); + + return [state.value, state.error, state.pending]; +} +/** + * Returns a function that can be used to force rerender react components + */ + +export function useForceUpdater(): () => void; +export function useForceUpdater(withDep: true): [unknown, () => void]; +export function useForceUpdater(withDep?: true) { + const r = useReducer(x => x + 1, 0); + return withDep ? r : r[1]; +} +/** + * A lazy component. The factory method is called on first render. For example useful + * for const Component = LazyComponent(() => findByDisplayName("...").default) + * @param factory Function returning a Component + * @returns Result of factory function + */ + +export function LazyComponent<T extends object = any>(factory: () => React.ComponentType<T>) { + const get = makeLazy(factory); + return (props: T) => { + const Component = get(); + return <Component {...props} />; + }; +} |