feat(ui/store): FavolinkStore class, createFavolinkStore, 관련 hook 추가 (#…

…315)

* feat(ui/store): FavolinkStore class, createFavolinkStore 추가

* feat(ui/store): store 관련 hook 추가

packages/ui/src/store/hooks.ts

@@ -0,0 +1,26 @@
+import { useSyncExternalStore } from 'react';
+import { type FavolinkStoreObserver } from './store';
+
+export function useFavolinkStore<T>(store: FavolinkStoreObserver<T>) {
+  const state = useSyncExternalStore(
+    store.subscribe,
+    store.getState,
+    store.getState,
+  );
+
+  return [state, store.setState] as const;
+}
+
+export function useFavolinkStoreValue<T>(store: FavolinkStoreObserver<T>) {
+  const state = useSyncExternalStore(
+    store.subscribe,
+    store.getState,
+    store.getState,
+  );
+
+  return state;
+}
+
+export function useSetFavolinkStore<T>(store: FavolinkStoreObserver<T>) {
+  return store.setState;
+}

packages/ui/src/store/index.ts

@@ -0,0 +1,11 @@
+/* eslint-disable @stylistic/padding-line-between-statements */
+export {
+  FavolinkStore,
+  type FavolinkStoreObserver,
+  createFavolinkStore,
+} from './store';
+export {
+  useFavolinkStore,
+  useFavolinkStoreValue,
+  useSetFavolinkStore,
+} from './hooks';

packages/ui/src/store/store.ts

@@ -0,0 +1,53 @@
+export interface FavolinkStoreObserver<T> {
+  getState: () => T;
+  setState: (next: SetStateAction<T>) => void;
+  subscribe: (listener: () => void) => () => void;
+  emitChange: () => void;
+}
+
+type SetStateFn<T> = (prevState: T) => T;
+
+type SetStateAction<T> = SetStateFn<T> | T;
+
+export class FavolinkStore<T> implements FavolinkStoreObserver<T> {
+  private state: T;
+  private listeners: (() => void)[] = [];
+
+  constructor(initialState: T) {
+    this.state = initialState;
+  }
+
+  getState = () => {
+    return this.state;
+  };
+
+  setState = (next: SetStateAction<T>) => {
+    const setter = next as SetStateFn<T>;
+    const nextValue = typeof next === 'function' ? setter(this.state) : next;
+
+    if (this.state === nextValue) {
+      return;
+    }
+
+    this.state = nextValue;
+    this.emitChange();
+  };
+
+  subscribe = (listener: () => void) => {
+    this.listeners = [...this.listeners, listener];
+
+    return () => {
+      this.listeners = this.listeners.filter((l) => l !== listener);
+    };
+  };
+
+  emitChange = () => {
+    this.listeners.forEach((listener) => {
+      listener();
+    });
+  };
+}
+
+export function createFavolinkStore<T>(initialState: T) {
+  return new FavolinkStore(initialState);
+}