Add ability to fetch external signaling settings

app/src/main/java/com/nextcloud/talk/controllers/CallController.java

@@ -461,7 +461,7 @@ public class CallController extends BaseController {
             }
 
             if (!inCall) {
-                startCall();
+                fetchSignalingSettings();
             }
         } else if (getActivity() != null && EffortlessPermissions.somePermissionPermanentlyDenied(getActivity(),
                 PERMISSIONS_CALL)) {
@@ -500,7 +500,7 @@ public class CallController extends BaseController {
         }
 
         if (!inCall) {
-            startCall();
+            fetchSignalingSettings();
         }
     }
 
@@ -518,7 +518,7 @@ public class CallController extends BaseController {
                 EffortlessPermissions.hasPermissions(getActivity(), PERMISSIONS_MICROPHONE))) {
             checkIfSomeAreApproved();
         } else if (!inCall) {
-            startCall();
+            fetchSignalingSettings();
         }
     }
 
@@ -652,7 +652,7 @@ public class CallController extends BaseController {
             }
 
             if (isVoiceOnlyCall && !inCall) {
-                startCall();
+                fetchSignalingSettings();
             }
 
         } else if (getActivity() != null && EffortlessPermissions.somePermissionPermanentlyDenied(getActivity(),
@@ -780,9 +780,6 @@ public class CallController extends BaseController {
         }
     }
 
-    private void startCall() {
-        startPullingSignalingMessages();
-    }
 
     private void animateCallControls(boolean show, long startDelay) {
         if (isVoiceOnlyCall) {
@@ -878,7 +875,7 @@ public class CallController extends BaseController {
         super.onDestroy();
     }
 
-    private void startPullingSignalingMessages() {
+    private void fetchSignalingSettings() {
         leavingCall = false;
 
         ncApi.getSignalingSettings(credentials, ApiUtils.getUrlForSignalingSettings(baseUrl))

app/src/main/java/com/nextcloud/talk/models/json/signaling/settings/Settings.java

@@ -35,4 +35,10 @@ public class Settings {
 
     @JsonField(name = "turnservers")
     List<IceServer> turnServers;
+
+    @JsonField(name = "server")
+    String externalSignalingServer;
+
+    @JsonField(name = "ticket")
+    String externalSignalingTicket;
 }

app/src/main/java/com/nextcloud/talk/webrtc/ScarletHelper.java

@@ -24,15 +24,11 @@ import com.nextcloud.talk.api.ExternalSignaling;
 import com.nextcloud.talk.application.NextcloudTalkApplication;
 import com.tinder.scarlet.Scarlet;
 import com.tinder.scarlet.messageadapter.moshi.MoshiMessageAdapter;
-import com.tinder.scarlet.retry.ExponentialBackoffStrategy;
 import com.tinder.scarlet.retry.LinearBackoffStrategy;
 import com.tinder.scarlet.streamadapter.rxjava2.RxJava2StreamAdapterFactory;
 import com.tinder.scarlet.websocket.okhttp.OkHttpClientUtils;
-import com.tinder.scarlet.websocket.okhttp.OkHttpWebSocket;
 
-import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 
 import javax.inject.Inject;