Made fast reconnect when network becomes up. (#28)

* Made fast reconnect when network becomes up.
* Use `retryPeersNow`

Author: Revertron

app/build.gradle

@@ -11,8 +11,8 @@ android {
         applicationId "eu.neilalexander.yggdrasil"
         minSdkVersion 21
         targetSdkVersion 29
-        versionCode 9
-        versionName "0.1"
+        versionCode 10
+        versionName "0.1-010"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }

app/src/main/AndroidManifest.xml

@@ -3,6 +3,7 @@
     package="eu.neilalexander.yggdrasil">
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
 
     <application
         android:name=".GlobalApplication"

app/src/main/java/eu/neilalexander/yggdrasil/GlobalApplication.kt

@@ -9,6 +9,7 @@ class GlobalApplication: Application() {
     override fun onCreate() {
         super.onCreate()
         config = ConfigurationProxy(applicationContext)
+        val callback = NetworkStateCallback(this)
     }
 
     fun subscribe() {

app/src/main/java/eu/neilalexander/yggdrasil/NetworkStateCallback.kt

@@ -0,0 +1,41 @@
+package eu.neilalexander.yggdrasil
+
+import android.content.Context
+import android.content.Intent
+import android.net.*
+import android.util.Log
+
+
+private const val TAG = "Network"
+
+class NetworkStateCallback(val context: Context) : ConnectivityManager.NetworkCallback() {
+
+    init {
+        val request = NetworkRequest.Builder()
+            .addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
+            .addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)
+            .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+            .build()
+
+        val manager = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
+        manager.registerNetworkCallback(request, this)
+    }
+
+    override fun onAvailable(network: Network) {
+        super.onAvailable(network)
+        Log.d(TAG, "onAvailable")
+
+        Thread {
+            // The message often arrives before the connection is fully established
+            Thread.sleep(1000)
+            val intent = Intent(context, PacketTunnelProvider::class.java)
+            intent.action = PacketTunnelProvider.ACTION_CONNECT
+            context.startService(intent)
+        }.start()
+    }
+
+    override fun onLost(network: Network) {
+        super.onLost(network)
+        Log.d(TAG, "onLost")
+    }
+}

app/src/main/java/eu/neilalexander/yggdrasil/PacketTunnelProvider.kt

@@ -21,6 +21,7 @@ class PacketTunnelProvider: VpnService() {
 
         const val ACTION_START = "eu.neilalexander.yggdrasil.PacketTunnelProvider.START"
         const val ACTION_STOP = "eu.neilalexander.yggdrasil.PacketTunnelProvider.STOP"
+        const val ACTION_CONNECT = "eu.neilalexander.yggdrasil.PacketTunnelProvider.CONNECT"
     }
 
     private var yggdrasil = Yggdrasil()
@@ -56,6 +57,10 @@ class PacketTunnelProvider: VpnService() {
                 Log.d(TAG, "Stopping...")
                 stop(); START_NOT_STICKY
             }
+            ACTION_CONNECT -> {
+                Log.d(TAG, "Connecting...")
+                connect(); START_STICKY
+            }
             else -> {
                 Log.d(TAG, "Starting...")
                 start(); START_STICKY
@@ -181,6 +186,13 @@ class PacketTunnelProvider: VpnService() {
         stopSelf()
     }
 
+    private fun connect() {
+        if (!started.get()) {
+            return
+        }
+        yggdrasil.retryPeersNow()
+    }
+
     private fun updater() {
         updates@ while (started.get()) {
             if ((application as  GlobalApplication).needUiUpdates()) {
@@ -260,4 +272,4 @@ class PacketTunnelProvider: VpnService() {
             readerStream = null
         }
     }
-}
+}