extract auth to lib

src/auth/createAuthContext.tsx

@@ -0,0 +1,90 @@
+import { createContext, useCallback, useContext, useMemo, useState } from 'react';
+import type { ReactNode } from 'react';
+
+const DEFAULT_AUTH_TOKEN_KEY = 'authToken';
+const DEFAULT_REFRESH_TOKEN_KEY = 'refreshToken';
+const DEFAULT_LEGACY_KEYS = ['auth_token', 'auth_user', 'token'];
+
+export type AuthState<TUser> = {
+  authToken: string | null;
+  refreshToken: string | null;
+  currentUser: TUser | null;
+};
+
+export type AuthContextValue<TUser> = AuthState<TUser> & {
+  setSession: (authToken: string, refreshToken: string, currentUser: TUser) => void;
+  setCurrentUser: (currentUser: TUser | null) => void;
+  clearSession: () => void;
+};
+
+export type CreateAuthContextOptions = {
+  authTokenKey?: string;
+  refreshTokenKey?: string;
+  legacyKeys?: string[];
+};
+
+export function createAuthContext<TUser>(options: CreateAuthContextOptions = {}) {
+  const authTokenKey = options.authTokenKey ?? DEFAULT_AUTH_TOKEN_KEY;
+  const refreshTokenKey = options.refreshTokenKey ?? DEFAULT_REFRESH_TOKEN_KEY;
+  const legacyKeys = options.legacyKeys ?? DEFAULT_LEGACY_KEYS;
+
+  const AuthContext = createContext<AuthContextValue<TUser> | undefined>(undefined);
+
+  function readStoredSession(): AuthState<TUser> {
+    for (const key of legacyKeys) {
+      localStorage.removeItem(key);
+    }
+
+    const authToken = localStorage.getItem(authTokenKey);
+    const refreshToken = localStorage.getItem(refreshTokenKey);
+
+    return {
+      authToken,
+      refreshToken,
+      currentUser: null
+    };
+  }
+
+  function AuthProvider({ children }: Readonly<{ children: ReactNode }>) {
+    const [state, setState] = useState<AuthState<TUser>>(readStoredSession);
+
+    const setSession = useCallback((authToken: string, refreshToken: string, currentUser: TUser) => {
+      localStorage.setItem(authTokenKey, authToken);
+      localStorage.setItem(refreshTokenKey, refreshToken);
+      setState({ authToken, refreshToken, currentUser });
+    }, []);
+
+    const clearSession = useCallback(() => {
+      localStorage.removeItem(authTokenKey);
+      localStorage.removeItem(refreshTokenKey);
+      setState({ authToken: null, refreshToken: null, currentUser: null });
+    }, []);
+
+    const setCurrentUser = useCallback((currentUser: TUser | null) => {
+      setState((prev) => ({ ...prev, currentUser }));
+    }, []);
+
+    const value = useMemo<AuthContextValue<TUser>>(() => ({
+      ...state,
+      setSession,
+      setCurrentUser,
+      clearSession
+    }), [state, setSession, setCurrentUser, clearSession]);
+
+    return <AuthContext.Provider value={value}>{children}</AuthContext.Provider>;
+  }
+
+  function useAuth() {
+    const ctx = useContext(AuthContext);
+    if (!ctx) {
+      throw new Error('useAuth must be used within AuthProvider');
+    }
+    return ctx;
+  }
+
+  return {
+    AuthProvider,
+    useAuth,
+    AuthContext
+  };
+}