create netinfo lib

src/lib/net-info.ts

···
+import NetInfo, {
+  NetInfoState,
+  NetInfoSubscription,
+} from '@react-native-community/netinfo'
+
+type NetworkStateChangeListener = (state: NetInfoState) => void
+
+class NetInfoAPI {
+  private subscription: NetInfoSubscription | null = null
+  private listeners: NetworkStateChangeListener[] = []
+
+  constructor() {
+    this.subscribe()
+  }
+
+  private subscribe() {
+    this.subscription = NetInfo.addEventListener(this.handleNetworkStateChange)
+  }
+
+  private handleNetworkStateChange = (state: NetInfoState) => {
+    this.listeners.forEach(listener => listener(state))
+  }
+
+  public addListener(listener: NetworkStateChangeListener) {
+    this.listeners.push(listener)
+  }
+
+  public removeListener(listener: NetworkStateChangeListener) {
+    const index = this.listeners.indexOf(listener)
+    if (index !== -1) {
+      this.listeners.splice(index, 1)
+    }
+  }
+}
+
+export const netInfoAPI = new NetInfoAPI()