Rocket.Chat.ReactNative/app/lib/store/internetStateMiddleware.ts

import NetInfo, { NetInfoState, NetInfoStateType } from '@react-native-community/netinfo';

import { setInternetType } from '../../actions/app';

export default () =>
	(createStore: any) =>
	(...args: any) => {
		const store = createStore(...args);

		let currentType: NetInfoStateType | undefined;

		const handleInternetStateChange = (nextState: NetInfoState) => {
			if (nextState.type !== currentType) {
				store.dispatch(setInternetType(nextState.type));
				currentType = nextState.type;
			}
		};

		NetInfo.addEventListener(handleInternetStateChange);
		return store;
	};