Create a class instead of an extension

src/main/java/com/infomaniak/lib/core/networking/NetworkAvailability.kt

@@ -0,0 +1,117 @@
+/*
+ * Infomaniak Core - Android
+ * Copyright (C) 2024 Infomaniak Network SA
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+package com.infomaniak.lib.core.networking
+
+import android.content.Context
+import android.net.ConnectivityManager
+import android.net.ConnectivityManager.NetworkCallback
+import android.net.Network
+import android.net.NetworkCapabilities
+import android.net.NetworkRequest
+import android.os.Build
+import io.sentry.Sentry
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.channels.ProducerScope
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.callbackFlow
+import kotlinx.coroutines.launch
+
+class NetworkAvailability(private val context: Context) {
+
+    private val connectivityManager by lazy { context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager }
+
+    val isNetworkAvailable: Flow<Boolean> = callbackFlow {
+        val networks = mutableSetOf<Network>()
+
+        val callback = object : NetworkCallback() {
+
+            override fun onAvailable(network: Network) {
+                networks.add(network)
+                sendNetworkAvailability(networks)
+            }
+
+            override fun onLost(network: Network) {
+                networks.remove(network)
+                sendNetworkAvailability(networks)
+            }
+        }
+
+        launch(Dispatchers.IO) {
+            send(getInitialNetworkAvailability(connectivityManager))
+        }
+
+        registerNetworkCallback(connectivityManager, callback)
+
+        awaitClose { unregisterNetworkCallback(connectivityManager, callback) }
+    }
+
+    private suspend fun ProducerScope<Boolean>.registerNetworkCallback(
+        connectivityManager: ConnectivityManager,
+        callback: NetworkCallback,
+    ) {
+        runCatching {
+            connectivityManager.registerNetworkCallback(networkRequestBuilder(), callback)
+        }.onFailure { exception ->
+            // Fix potential Exception thrown by ConnectivityManager on Android 11
+            // Already fixed in Android S and above
+            // https://issuetracker.google.com/issues/175055271
+            Sentry.captureException(exception)
+            send(false)
+        }
+    }
+
+    private fun unregisterNetworkCallback(connectivityManager: ConnectivityManager, callback: NetworkCallback) {
+        runCatching {
+            connectivityManager.unregisterNetworkCallback(callback)
+        }.onFailure { exception ->
+            Sentry.captureException(exception)
+        }
+    }
+
+    @Suppress("DEPRECATION")
+    private fun getInitialNetworkAvailability(connectivityManager: ConnectivityManager): Boolean {
+        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+            connectivityManager.activeNetwork?.let(::hasInternetConnectivity) ?: false
+        } else {
+            connectivityManager.activeNetworkInfo?.isConnected ?: false
+        }
+    }
+
+    private fun ProducerScope<Boolean>.sendNetworkAvailability(networks: MutableSet<Network>) {
+        launch(Dispatchers.IO) {
+            send(hasAvailableNetwork(networks))
+        }
+    }
+
+    private fun networkRequestBuilder(): NetworkRequest {
+        return NetworkRequest.Builder().apply {
+            addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
+        }.build()
+    }
+
+    private fun hasInternetConnectivity(network: Network) = runCatching {
+        network.getByName(ROOT_SERVER_URL) != null
+    }.getOrDefault(false)
+
+    private fun hasAvailableNetwork(networks: MutableSet<Network>) = networks.any(::hasInternetConnectivity)
+
+    companion object {
+        private const val ROOT_SERVER_URL = "a.root-servers.net"
+    }
+}