Listen to hotspot state changes

app/src/main/java/org/kiwix/kiwixmobile/di/modules/ServiceModule.kt

@@ -10,6 +10,8 @@ import org.kiwix.kiwixlib.JNIKiwixServer
 import org.kiwix.kiwixmobile.di.ServiceScope
 import org.kiwix.kiwixmobile.webserver.WebServerHelper
 import org.kiwix.kiwixmobile.wifi_hotspot.HotspotNotificationManager
+import org.kiwix.kiwixmobile.wifi_hotspot.HotspotStateReceiver
+import org.kiwix.kiwixmobile.wifi_hotspot.HotspotStateReceiver.Callback
 import org.kiwix.kiwixmobile.wifi_hotspot.IpAddressCallbacks
 
 @Module
@@ -44,4 +46,16 @@ class ServiceModule {
     context: Context
   ): HotspotNotificationManager =
     HotspotNotificationManager(notificationManager, context)
+
+  @Provides
+  @ServiceScope
+  fun providesHotspotStateReceiver(
+    callback: Callback
+  ): HotspotStateReceiver = HotspotStateReceiver(callback)
+
+  @Provides
+  @ServiceScope
+  fun providesHotspotStateReceiverCallback(
+    service: Service
+  ): HotspotStateReceiver.Callback = service as Callback
 }

app/src/main/java/org/kiwix/kiwixmobile/wifi_hotspot/HotspotService.java

@@ -10,6 +10,7 @@ import androidx.annotation.Nullable;
 import javax.inject.Inject;
 import org.kiwix.kiwixmobile.KiwixApplication;
 import org.kiwix.kiwixmobile.R;
+import org.kiwix.kiwixmobile.extensions.ContextExtensionsKt;
 import org.kiwix.kiwixmobile.utils.ServerUtils;
 import org.kiwix.kiwixmobile.webserver.WebServerHelper;
 import org.kiwix.kiwixmobile.webserver.ZimHostCallbacks;
@@ -22,7 +23,8 @@ import static org.kiwix.kiwixmobile.wifi_hotspot.HotspotNotificationManager.HOTS
  * Created by Adeel Zafar on 07/01/2019.
  */
 
-public class HotspotService extends Service implements IpAddressCallbacks {
+public class HotspotService extends Service
+  implements IpAddressCallbacks, HotspotStateReceiver.Callback {
 
   public static final String ACTION_START_SERVER = "start_server";
   public static final String ACTION_STOP_SERVER = "stop_server";
@@ -35,6 +37,8 @@ public class HotspotService extends Service implements IpAddressCallbacks {
   WebServerHelper webServerHelper;
   @Inject
   HotspotNotificationManager hotspotNotificationManager;
+  @Inject
+  HotspotStateReceiver hotspotStateReceiver;
 
   @Override public void onCreate() {
     KiwixApplication.getApplicationComponent()
@@ -43,6 +47,12 @@ public class HotspotService extends Service implements IpAddressCallbacks {
       .build()
       .inject(this);
     super.onCreate();
+    ContextExtensionsKt.registerReceiver(this, hotspotStateReceiver);
+  }
+
+  @Override public void onDestroy() {
+    unregisterReceiver(hotspotStateReceiver);
+    super.onDestroy();
   }
 
   @Override public int onStartCommand(@NonNull Intent intent, int flags, int startId) {
@@ -111,6 +121,10 @@ public class HotspotService extends Service implements IpAddressCallbacks {
     }
   }
 
+  @Override public void onHotspotDisabled() {
+    stopHotspotAndDismissNotification();
+  }
+
   public class HotspotBinder extends Binder {
 
     @NonNull public HotspotService getService() {

app/src/main/java/org/kiwix/kiwixmobile/wifi_hotspot/HotspotStateReceiver.kt

@@ -0,0 +1,63 @@
+/*
+ * Kiwix Android
+ * Copyright (C) 2018  Kiwix <android.kiwix.org>
+ *
+ * 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 org.kiwix.kiwixmobile.wifi_hotspot
+
+import android.content.Context
+import android.content.Intent
+import org.kiwix.kiwixmobile.wifi_hotspot.HotspotStateReceiver.HotspotState.DISABLED
+import org.kiwix.kiwixmobile.zim_manager.BaseBroadcastReceiver
+import javax.inject.Inject
+
+const val EXTRA_WIFI_AP_STATE = "wifi_state"
+const val ACTION_WIFI_AP_STATE = "android.net.wifi.WIFI_AP_STATE_CHANGED"
+
+const val WIFI_AP_STATE_DISABLING = 10
+const val WIFI_AP_STATE_DISABLED = 11
+const val WIFI_AP_STATE_ENABLING = 12
+const val WIFI_AP_STATE_ENABLED = 13
+const val WIFI_AP_STATE_FAILED = 14
+
+class HotspotStateReceiver @Inject constructor(val callback: Callback) : BaseBroadcastReceiver() {
+  override val action: String = ACTION_WIFI_AP_STATE
+
+  override fun onIntentWithActionReceived(context: Context, intent: Intent) {
+    if (DISABLED == hotspotState(intent)) {
+      callback.onHotspotDisabled()
+    }
+  }
+
+  private fun hotspotState(intent: Intent) =
+    HotspotState.from(intent.getIntExtra(EXTRA_WIFI_AP_STATE, -1))
+
+  interface Callback {
+    fun onHotspotDisabled()
+  }
+
+  private enum class HotspotState(val state: Int) {
+
+    DISABLING(WIFI_AP_STATE_DISABLING),
+    DISABLED(WIFI_AP_STATE_DISABLED),
+    ENABLING(WIFI_AP_STATE_ENABLING),
+    ENABLED(WIFI_AP_STATE_ENABLED),
+    FAILED(WIFI_AP_STATE_FAILED);
+
+    companion object {
+      fun from(state: Int) = HotspotState.values().firstOrNull { state == it.state }
+    }
+  }
+}