Add Group Call peeking in the Conversation view.

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationActivity.java

@@ -25,6 +25,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.pm.ShortcutManager;
+import android.content.res.ColorStateList;
 import android.content.res.Configuration;
 import android.graphics.Bitmap;
 import android.graphics.Color;
@@ -82,6 +83,7 @@ import com.annimon.stream.Stream;
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
 import com.bumptech.glide.request.target.CustomTarget;
 import com.bumptech.glide.request.transition.Transition;
+import com.google.android.material.button.MaterialButton;
 
 import org.greenrobot.eventbus.EventBus;
 import org.greenrobot.eventbus.Subscribe;
@@ -135,6 +137,7 @@ import org.thoughtcrime.securesms.contactshare.SimpleTextWatcher;
 import org.thoughtcrime.securesms.conversation.ConversationGroupViewModel.GroupActiveState;
 import org.thoughtcrime.securesms.conversation.ConversationMessage.ConversationMessageFactory;
 import org.thoughtcrime.securesms.conversation.ui.error.SafetyNumberChangeDialog;
+import org.thoughtcrime.securesms.conversation.ui.groupcall.GroupCallViewModel;
 import org.thoughtcrime.securesms.conversation.ui.mentions.MentionsPickerViewModel;
 import org.thoughtcrime.securesms.conversationlist.model.MessageResult;
 import org.thoughtcrime.securesms.crypto.SecurityEvent;
@@ -159,6 +162,7 @@ import org.thoughtcrime.securesms.database.model.MmsMessageRecord;
 import org.thoughtcrime.securesms.database.model.ReactionRecord;
 import org.thoughtcrime.securesms.database.model.StickerRecord;
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
+import org.thoughtcrime.securesms.events.GroupCallPeekEvent;
 import org.thoughtcrime.securesms.events.ReminderUpdateEvent;
 import org.thoughtcrime.securesms.giph.ui.GiphyActivity;
 import org.thoughtcrime.securesms.groups.GroupChangeException;
@@ -369,6 +373,7 @@ public class ConversationActivity extends PassphraseRequiredActivity
   private   View                     requestingMemberBanner;
   private   View                     cancelJoinRequest;
   private   Stub<View>               mentionsSuggestions;
+  private   MaterialButton           joinGroupCallButton;
 
   private LinkPreviewViewModel         linkPreviewViewModel;
   private ConversationSearchViewModel  searchViewModel;
@@ -377,6 +382,7 @@ public class ConversationActivity extends PassphraseRequiredActivity
   private InviteReminderModel          inviteReminderModel;
   private ConversationGroupViewModel   groupViewModel;
   private MentionsPickerViewModel      mentionsViewModel;
+  private GroupCallViewModel           groupCallViewModel;
 
   private LiveRecipient recipient;
   private long          threadId;
@@ -426,6 +432,7 @@ public class ConversationActivity extends PassphraseRequiredActivity
     initializeViewModel(args);
     initializeGroupViewModel();
     initializeMentionsViewModel();
+    initializeGroupCallViewModel();
     initializeEnabledCheck();
     initializePendingRequestsBanner();
     initializeGroupV1MigrationsBanners();
@@ -532,6 +539,10 @@ public class ConversationActivity extends PassphraseRequiredActivity
                              .enqueue();
     }
 
+    if (groupCallViewModel != null) {
+      groupCallViewModel.peekGroupCall(this);
+    }
+
     setVisibleThread(threadId);
     ConversationUtil.refreshRecipientShortcuts();
   }
@@ -816,6 +827,9 @@ public class ConversationActivity extends PassphraseRequiredActivity
     } else if (isGroupConversation()) {
       if (isActiveV2Group && FeatureFlags.groupCalling()) {
         inflater.inflate(R.menu.conversation_callable_groupv2, menu);
+        if (groupCallViewModel != null && Boolean.TRUE.equals(groupCallViewModel.hasActiveGroupCall().getValue())) {
+          hideMenuItem(menu, R.id.menu_video_secure);
+        }
       }
 
       inflater.inflate(R.menu.conversation_group_options, menu);
@@ -1895,6 +1909,7 @@ public class ConversationActivity extends PassphraseRequiredActivity
     noLongerMemberBanner   = findViewById(R.id.conversation_no_longer_member_banner);
     requestingMemberBanner = findViewById(R.id.conversation_requesting_banner);
     cancelJoinRequest      = findViewById(R.id.conversation_cancel_request);
+    joinGroupCallButton    = findViewById(R.id.conversation_group_cal_join);
 
     container.addOnKeyboardShownListener(this);
     inputPanel.setListener(this);
@@ -1949,6 +1964,8 @@ public class ConversationActivity extends PassphraseRequiredActivity
     inlineAttachmentButton.setOnClickListener(v -> handleAddAttachment());
 
     reactionOverlay.setOnReactionSelectedListener(this);
+
+    joinGroupCallButton.setOnClickListener(v -> handleVideo(getRecipient()));
   }
 
   protected void initializeActionBar() {
@@ -2105,6 +2122,21 @@ public class ConversationActivity extends PassphraseRequiredActivity
     });
   }
 
+  public void initializeGroupCallViewModel() {
+    groupCallViewModel = ViewModelProviders.of(this, new GroupCallViewModel.Factory()).get(GroupCallViewModel.class);
+
+    recipient.observe(this, r -> {
+      groupCallViewModel.onRecipientChange(this, r);
+    });
+
+    groupCallViewModel.hasActiveGroupCall().observe(this, hasActiveCall -> {
+      invalidateOptionsMenu();
+      joinGroupCallButton.setVisibility(hasActiveCall ? View.VISIBLE : View.GONE);
+    });
+
+    groupCallViewModel.canJoinGroupCall().observe(this, canJoin -> joinGroupCallButton.setText(canJoin ? R.string.ConversationActivity_join : R.string.ConversationActivity_full));
+  }
+
   private void showStickerIntroductionTooltip() {
     TextSecurePreferences.setMediaKeyboardMode(this, MediaKeyboardMode.STICKER);
     inputPanel.setMediaKeyboardToggleMode(true);
@@ -2218,6 +2250,10 @@ public class ConversationActivity extends PassphraseRequiredActivity
     if (mentionsViewModel != null) {
       mentionsViewModel.onRecipientChange(recipient);
     }
+
+    if (groupCallViewModel != null) {
+      groupCallViewModel.onRecipientChange(this, recipient);
+    }
   }
 
   @Subscribe(threadMode = ThreadMode.MAIN)
@@ -2239,6 +2275,13 @@ public class ConversationActivity extends PassphraseRequiredActivity
     }
   }
 
+  @Subscribe(threadMode = ThreadMode.MAIN, sticky = true)
+  public void onGroupCallPeekEvent(@NonNull GroupCallPeekEvent event) {
+    if (groupCallViewModel != null) {
+      groupCallViewModel.onGroupCallPeekEvent(event);
+    }
+  }
+
   private void initializeReceivers() {
     securityUpdateReceiver = new BroadcastReceiver() {
       @Override
@@ -2396,8 +2439,13 @@ public class ConversationActivity extends PassphraseRequiredActivity
   private void setActionBarColor(MaterialColor color) {
     ActionBar supportActionBar = getSupportActionBar();
     if (supportActionBar == null) throw new AssertionError();
-    supportActionBar.setBackgroundDrawable(new ColorDrawable(color.toActionBarColor(this)));
+    int actionBarColor = color.toActionBarColor(this);
+    supportActionBar.setBackgroundDrawable(new ColorDrawable(actionBarColor));
     WindowUtil.setStatusBarColor(getWindow(), color.toStatusBarColor(this));
+
+    joinGroupCallButton.setTextColor(actionBarColor);
+    joinGroupCallButton.setIconTint(ColorStateList.valueOf(actionBarColor));
+    joinGroupCallButton.setRippleColor(ColorStateList.valueOf(actionBarColor));
   }
 
   private void setBlockedUserState(Recipient recipient, boolean isSecureText, boolean isDefaultSms) {

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationUpdateItem.java

@@ -19,6 +19,7 @@ import org.thoughtcrime.securesms.BindableConversationItem;
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.VerifyIdentityActivity;
 import org.thoughtcrime.securesms.database.IdentityDatabase.IdentityRecord;
+import org.thoughtcrime.securesms.database.model.GroupCallUpdateDetailsUtil;
 import org.thoughtcrime.securesms.database.model.LiveUpdateMessage;
 import org.thoughtcrime.securesms.database.model.MessageRecord;
 import org.thoughtcrime.securesms.database.model.UpdateDescription;
@@ -182,14 +183,17 @@ public final class ConversationUpdateItem extends LinearLayout
         }
       });
     } else if (conversationMessage.getMessageRecord().isGroupCall()) {
-
       UpdateDescription updateDescription = MessageRecord.getGroupCallUpdateDescription(getContext(), conversationMessage.getMessageRecord().getBody(), true);
       Collection<UUID>  uuids             = updateDescription.getMentioned();
 
       int text = 0;
       if (Util.hasItems(uuids)) {
+        if (GroupCallUpdateDetailsUtil.parse(conversationMessage.getMessageRecord().getBody()).getIsCallFull()) {
+          text = R.string.ConversationUpdateItem_call_is_full;
+        } else {
           text = uuids.contains(TextSecurePreferences.getLocalUuid(getContext())) ? R.string.ConversationUpdateItem_return_to_call : R.string.ConversationUpdateItem_join_call;
         }
+      }
 
       if (text != 0) {
         actionButton.setText(text);

app/src/main/java/org/thoughtcrime/securesms/conversation/ui/groupcall/GroupCallViewModel.java

@@ -0,0 +1,90 @@
+package org.thoughtcrime.securesms.conversation.ui.groupcall;
+
+import android.content.Context;
+import android.content.Intent;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+import androidx.lifecycle.ViewModel;
+import androidx.lifecycle.ViewModelProvider;
+
+import org.thoughtcrime.securesms.events.GroupCallPeekEvent;
+import org.thoughtcrime.securesms.logging.Log;
+import org.thoughtcrime.securesms.recipients.Recipient;
+import org.thoughtcrime.securesms.ringrtc.RemotePeer;
+import org.thoughtcrime.securesms.service.WebRtcCallService;
+import org.thoughtcrime.securesms.util.FeatureFlags;
+
+import java.util.Objects;
+
+public class GroupCallViewModel extends ViewModel {
+
+  private static final String TAG = Log.tag(GroupCallViewModel.class);
+
+  private final MutableLiveData<Boolean> activeGroupCall;
+  private final MutableLiveData<Boolean> canJoin;
+
+  private @Nullable Recipient currentRecipient;
+
+  GroupCallViewModel() {
+    this.activeGroupCall = new MutableLiveData<>(false);
+    this.canJoin         = new MutableLiveData<>(false);
+  }
+
+  public @NonNull LiveData<Boolean> hasActiveGroupCall() {
+    return activeGroupCall;
+  }
+
+  public @NonNull LiveData<Boolean> canJoinGroupCall() {
+    return canJoin;
+  }
+
+  public void onRecipientChange(@NonNull Context context, @Nullable Recipient recipient) {
+    if (Objects.equals(currentRecipient, recipient)) {
+      return;
+    }
+
+    activeGroupCall.postValue(false);
+    canJoin.postValue(false);
+
+    currentRecipient = recipient;
+
+    peekGroupCall(context);
+  }
+
+  public void peekGroupCall(@NonNull Context context) {
+    if (isGroupCallCapable(currentRecipient)) {
+      Log.i(TAG, "peek call for " + currentRecipient.getId());
+      Intent intent = new Intent(context, WebRtcCallService.class);
+      intent.setAction(WebRtcCallService.ACTION_GROUP_CALL_PEEK)
+            .putExtra(WebRtcCallService.EXTRA_REMOTE_PEER, new RemotePeer(currentRecipient.getId()));
+
+      context.startService(intent);
+    }
+  }
+
+  public void onGroupCallPeekEvent(@NonNull GroupCallPeekEvent groupCallPeekEvent) {
+    if (isGroupCallCapable(currentRecipient) && groupCallPeekEvent.getGroupRecipientId().equals(currentRecipient.getId())) {
+      Log.i(TAG, "update UI with call event: active call: " + groupCallPeekEvent.hasActiveCall() + " canJoin: " + groupCallPeekEvent.canJoinCall());
+
+      activeGroupCall.postValue(groupCallPeekEvent.hasActiveCall());
+      canJoin.postValue(groupCallPeekEvent.canJoinCall());
+    } else {
+      Log.i(TAG, "Ignore call event for different recipient.");
+    }
+  }
+
+  private static boolean isGroupCallCapable(@Nullable Recipient recipient) {
+    return recipient != null && recipient.isActiveGroup() && recipient.isPushV2Group() && FeatureFlags.groupCalling();
+  }
+
+  public static final class Factory implements ViewModelProvider.Factory {
+    @Override
+    public @NonNull <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
+      //noinspection ConstantConditions
+      return modelClass.cast(new GroupCallViewModel());
+    }
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/database/MessageDatabase.java

@@ -133,12 +133,14 @@ public abstract class MessageDatabase extends Database implements MmsSmsColumns
   public abstract @NonNull Pair<Long, Long> insertReceivedCall(@NonNull RecipientId address, boolean isVideoOffer);
   public abstract @NonNull Pair<Long, Long> insertOutgoingCall(@NonNull RecipientId address, boolean isVideoOffer);
   public abstract @NonNull Pair<Long, Long> insertMissedCall(@NonNull RecipientId address, long timestamp, boolean isVideoOffer);
-  public abstract @NonNull void insertOrUpdateGroupCall(@NonNull RecipientId groupRecipientId,
+  public abstract void insertOrUpdateGroupCall(@NonNull RecipientId groupRecipientId,
                                                @NonNull RecipientId sender,
                                                long timestamp,
                                                @Nullable String messageGroupCallEraId,
                                                @Nullable String peekGroupCallEraId,
-                                                        @NonNull Collection<UUID> peekJoinedUuids);
+                                               @NonNull Collection<UUID> peekJoinedUuids,
+                                               boolean isCallFull);
+  public abstract boolean updatePreviousGroupCall(long threadId, @Nullable String peekGroupCallEraId, @NonNull Collection<UUID> peekJoinedUuids, boolean isCallFull);
 
   public abstract Optional<InsertResult> insertMessageInbox(IncomingTextMessage message, long type);
   public abstract Optional<InsertResult> insertMessageInbox(IncomingTextMessage message);

app/src/main/java/org/thoughtcrime/securesms/database/MmsDatabase.java

@@ -464,16 +464,22 @@ public class MmsDatabase extends MessageDatabase {
   }
 
   @Override
-  public @NonNull void insertOrUpdateGroupCall(@NonNull RecipientId groupRecipientId,
+  public void insertOrUpdateGroupCall(@NonNull RecipientId groupRecipientId,
                                       @NonNull RecipientId sender,
                                       long timestamp,
                                       @Nullable String messageGroupCallEraId,
                                       @Nullable String peekGroupCallEraId,
-                                               @NonNull Collection<UUID> peekJoinedUuids)
+                                      @NonNull Collection<UUID> peekJoinedUuids,
+                                      boolean isCallFull)
   {
     throw new UnsupportedOperationException();
   }
 
+  @Override
+  public boolean updatePreviousGroupCall(long threadId, @Nullable String peekGroupCallEraId, @NonNull Collection<UUID> peekJoinedUuids, boolean isCallFull) {
+    throw new UnsupportedOperationException();
+  }
+
   @Override
   public Optional<InsertResult> insertMessageInbox(IncomingTextMessage message, long type) {
     throw new UnsupportedOperationException();

app/src/main/java/org/thoughtcrime/securesms/database/SmsDatabase.java

@@ -691,7 +691,8 @@ public class SmsDatabase extends MessageDatabase {
                                       long timestamp,
                                       @Nullable String messageGroupCallEraId,
                                       @Nullable String peekGroupCallEraId,
-                                      @NonNull Collection<UUID> peekJoinedUuids)
+                                      @NonNull Collection<UUID> peekJoinedUuids,
+                                      boolean isCallFull)
   {
     SQLiteDatabase db        = databaseHelper.getWritableDatabase();
 
@@ -701,7 +702,7 @@ public class SmsDatabase extends MessageDatabase {
       Recipient recipient = Recipient.resolved(groupRecipientId);
       long      threadId  = DatabaseFactory.getThreadDatabase(context).getThreadIdFor(recipient);
 
-      boolean peerEraIdSameAsPrevious = updatePreviousGroupCall(threadId, peekGroupCallEraId, peekJoinedUuids);
+      boolean peerEraIdSameAsPrevious = updatePreviousGroupCall(threadId, peekGroupCallEraId, peekJoinedUuids, isCallFull);
 
       if (!peerEraIdSameAsPrevious && !Util.isEmpty(peekGroupCallEraId)) {
         Recipient self     = Recipient.self();
@@ -712,6 +713,7 @@ public class SmsDatabase extends MessageDatabase {
                                                      .setStartedCallUuid(Recipient.resolved(sender).requireUuid().toString())
                                                      .setStartedCallTimestamp(timestamp)
                                                      .addAllInCallUuids(Stream.of(peekJoinedUuids).map(UUID::toString).toList())
+                                                     .setIsCallFull(isCallFull)
                                                      .build()
                                                      .toByteArray();
 
@@ -743,7 +745,8 @@ public class SmsDatabase extends MessageDatabase {
     }
   }
 
-  private boolean updatePreviousGroupCall(long threadId, @Nullable String peekGroupCallEraId, @NonNull Collection<UUID> peekJoinedUuids) {
+  @Override
+  public boolean updatePreviousGroupCall(long threadId, @Nullable String peekGroupCallEraId, @NonNull Collection<UUID> peekJoinedUuids, boolean isCallFull) {
     SQLiteDatabase db    = databaseHelper.getWritableDatabase();
     String         where = TYPE + " = ? AND " + THREAD_ID + " = ?";
     String[]       args  = SqlUtil.buildArgs(Types.GROUP_CALL_TYPE, threadId);
@@ -761,7 +764,7 @@ public class SmsDatabase extends MessageDatabase {
       List<String> inCallUuids = sameEraId ? Stream.of(peekJoinedUuids).map(UUID::toString).toList()
                                            : Collections.emptyList();
 
-      String body = GroupCallUpdateDetailsUtil.createUpdatedBody(groupCallUpdateDetails, inCallUuids);
+      String body = GroupCallUpdateDetailsUtil.createUpdatedBody(groupCallUpdateDetails, inCallUuids, isCallFull);
 
       ContentValues contentValues = new ContentValues();
       contentValues.put(BODY, body);

app/src/main/java/org/thoughtcrime/securesms/database/model/GroupCallUpdateDetailsUtil.java

@@ -34,8 +34,9 @@ public final class GroupCallUpdateDetailsUtil {
     return groupCallUpdateDetails;
   }
 
-  public static @NonNull String createUpdatedBody(@NonNull GroupCallUpdateDetails groupCallUpdateDetails, @NonNull List<String> inCallUuids) {
+  public static @NonNull String createUpdatedBody(@NonNull GroupCallUpdateDetails groupCallUpdateDetails, @NonNull List<String> inCallUuids, boolean isCallFull) {
     GroupCallUpdateDetails.Builder builder = groupCallUpdateDetails.toBuilder()
+                                                                   .setIsCallFull(isCallFull)
                                                                    .clearInCallUuids();
 
     if (Util.hasItems(inCallUuids)) {

app/src/main/java/org/thoughtcrime/securesms/events/GroupCallPeekEvent.java

@@ -0,0 +1,32 @@
+package org.thoughtcrime.securesms.events;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import org.thoughtcrime.securesms.recipients.RecipientId;
+
+public final class GroupCallPeekEvent {
+  private final RecipientId groupRecipientId;
+  private final String      eraId;
+  private final long        deviceCount;
+  private final long        deviceLimit;
+
+  public GroupCallPeekEvent(@NonNull RecipientId groupRecipientId, @Nullable String eraId, @Nullable Long deviceCount, @Nullable Long deviceLimit) {
+    this.groupRecipientId = groupRecipientId;
+    this.eraId            = eraId;
+    this.deviceCount      = deviceCount != null ? deviceCount : 0;
+    this.deviceLimit      = deviceLimit != null ? deviceLimit : 0;
+  }
+
+  public @NonNull RecipientId getGroupRecipientId() {
+    return groupRecipientId;
+  }
+
+  public boolean hasActiveCall() {
+    return eraId != null && deviceCount > 0;
+  }
+
+  public boolean canJoinCall() {
+    return hasActiveCall() && deviceCount < deviceLimit;
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/service/WebRtcCallService.java

@@ -35,6 +35,7 @@ import org.thoughtcrime.securesms.crypto.IdentityKeyParcelable;
 import org.thoughtcrime.securesms.crypto.UnidentifiedAccessUtil;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
+import org.thoughtcrime.securesms.events.GroupCallPeekEvent;
 import org.thoughtcrime.securesms.events.WebRtcViewModel;
 import org.thoughtcrime.securesms.groups.GroupId;
 import org.thoughtcrime.securesms.groups.GroupManager;
@@ -52,6 +53,7 @@ import org.thoughtcrime.securesms.ringrtc.TurnServerInfoParcel;
 import org.thoughtcrime.securesms.service.webrtc.IdleActionProcessor;
 import org.thoughtcrime.securesms.service.webrtc.WebRtcData;
 import org.thoughtcrime.securesms.service.webrtc.WebRtcInteractor;
+import org.thoughtcrime.securesms.service.webrtc.WebRtcUtil;
 import org.thoughtcrime.securesms.service.webrtc.state.WebRtcServiceState;
 import org.thoughtcrime.securesms.util.FutureTaskListener;
 import org.thoughtcrime.securesms.util.ListenableFutureTask;
@@ -200,6 +202,7 @@ public class WebRtcCallService extends Service implements CallManager.Observer,
   public static final String ACTION_GROUP_UPDATE_RENDERED_RESOLUTIONS = "GROUP_UPDATE_RENDERED_RESOLUTIONS";
   public static final String ACTION_GROUP_CALL_ENDED                  = "GROUP_CALL_ENDED";
   public static final String ACTION_GROUP_CALL_UPDATE_MESSAGE         = "GROUP_CALL_UPDATE_MESSAGE";
+  public static final String ACTION_GROUP_CALL_PEEK                   = "GROUP_CALL_PEEK";
 
   public static final int BUSY_TONE_LENGTH = 2000;
 
@@ -686,25 +689,59 @@ public class WebRtcCallService extends Service implements CallManager.Observer,
                                                                        groupCallUpdateMetadata.getServerReceivedTimestamp(),
                                                                        groupCallUpdateMetadata.getGroupCallEraId(),
                                                                        peekInfo.getEraId(),
-                                                                       peekInfo.getJoinedMembers());
+                                                                       peekInfo.getJoinedMembers(),
+                                                                       WebRtcUtil.isCallFull(peekInfo));
 
           long threadId = DatabaseFactory.getThreadDatabase(this).getThreadIdFor(group);
           ApplicationDependencies.getMessageNotifier().updateNotification(this, threadId, true);
+
+          EventBus.getDefault().postSticky(new GroupCallPeekEvent(group.getId(), peekInfo.getEraId(), peekInfo.getDeviceCount(), peekInfo.getMaxDevices()));
         });
 
       } catch (IOException | VerificationFailedException | CallException e) {
-        Log.e(TAG, "error peeking", e);
+        Log.e(TAG, "error peeking from message", e);
       }
     });
   }
 
-  public void updateGroupCallUpdateMessage(@NonNull RecipientId groupId, @Nullable String groupCallEraId, @NonNull Collection<UUID> joinedMembers) {
+  public void peekGroupCall(@NonNull RecipientId id) {
+    networkExecutor.execute(() -> {
+      try {
+        Recipient               group      = Recipient.resolved(id);
+        GroupId.V2              groupId    = group.requireGroupId().requireV2();
+        GroupExternalCredential credential = GroupManager.getGroupExternalCredential(this, groupId);
+
+        List<GroupCall.GroupMemberInfo> members = Stream.of(GroupManager.getUuidCipherTexts(this, groupId))
+                                                        .map(entry -> new GroupCall.GroupMemberInfo(entry.getKey(), entry.getValue().serialize()))
+                                                        .toList();
+
+        callManager.peekGroupCall(BuildConfig.SIGNAL_SFU_URL, credential.getTokenBytes().toByteArray(), members, peekInfo -> {
+          long threadId = DatabaseFactory.getThreadDatabase(this).getThreadIdFor(group);
+
+          DatabaseFactory.getSmsDatabase(this).updatePreviousGroupCall(threadId,
+                                                                       peekInfo.getEraId(),
+                                                                       peekInfo.getJoinedMembers(),
+                                                                       WebRtcUtil.isCallFull(peekInfo));
+
+          ApplicationDependencies.getMessageNotifier().updateNotification(this, threadId, true);
+
+          EventBus.getDefault().postSticky(new GroupCallPeekEvent(id, peekInfo.getEraId(), peekInfo.getDeviceCount(), peekInfo.getMaxDevices()));
+        });
+
+      } catch (IOException | VerificationFailedException | CallException e) {
+        Log.e(TAG, "error peeking from active conversation", e);
+      }
+    });
+  }
+
+  public void updateGroupCallUpdateMessage(@NonNull RecipientId groupId, @Nullable String groupCallEraId, @NonNull Collection<UUID> joinedMembers, boolean isCallFull) {
     DatabaseFactory.getSmsDatabase(this).insertOrUpdateGroupCall(groupId,
                                                                  Recipient.self().getId(),
                                                                  System.currentTimeMillis(),
                                                                  null,
                                                                  groupCallEraId,
-                                                                 joinedMembers);
+                                                                 joinedMembers,
+                                                                 isCallFull);
   }
 
   @Override

app/src/main/java/org/thoughtcrime/securesms/service/webrtc/GroupConnectedActionProcessor.java

@@ -125,7 +125,7 @@ public class GroupConnectedActionProcessor extends GroupActionProcessor {
     if (!members.contains(Recipient.self().requireUuid())) {
       members.add(Recipient.self().requireUuid());
     }
-    webRtcInteractor.updateGroupCallUpdateMessage(currentState.getCallInfoState().getCallRecipient().getId(), eraId, members);
+    webRtcInteractor.updateGroupCallUpdateMessage(currentState.getCallInfoState().getCallRecipient().getId(), eraId, members, WebRtcUtil.isCallFull(peekInfo));
 
     return currentState.builder()
                        .changeCallSetupState()
@@ -149,7 +149,7 @@ public class GroupConnectedActionProcessor extends GroupActionProcessor {
     webRtcInteractor.sendGroupCallMessage(currentState.getCallInfoState().getCallRecipient(), eraId);
 
     List<UUID> members = Stream.of(currentState.getCallInfoState().getRemoteCallParticipants()).map(p -> p.getRecipient().requireUuid()).toList();
-    webRtcInteractor.updateGroupCallUpdateMessage(currentState.getCallInfoState().getCallRecipient().getId(), eraId, members);
+    webRtcInteractor.updateGroupCallUpdateMessage(currentState.getCallInfoState().getCallRecipient().getId(), eraId, members, false);
 
     currentState = currentState.builder()
                                .changeCallInfoState()

app/src/main/java/org/thoughtcrime/securesms/service/webrtc/WebRtcActionProcessor.java

@@ -61,6 +61,7 @@ import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_ENDED_
 import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_ENDED_TIMEOUT;
 import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_FLIP_CAMERA;
 import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_GROUP_CALL_ENDED;
+import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_GROUP_CALL_PEEK;
 import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_GROUP_CALL_UPDATE_MESSAGE;
 import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_GROUP_JOINED_MEMBERSHIP_CHANGED;
 import static org.thoughtcrime.securesms.service.WebRtcCallService.ACTION_GROUP_LOCAL_DEVICE_STATE_CHANGED;
@@ -238,6 +239,7 @@ public abstract class WebRtcActionProcessor {
       case ACTION_GROUP_UPDATE_RENDERED_RESOLUTIONS:   return handleUpdateRenderedResolutions(currentState);
       case ACTION_GROUP_CALL_ENDED:                    return handleGroupCallEnded(currentState, getGroupCallHash(intent), getGroupCallEndReason(intent));
       case ACTION_GROUP_CALL_UPDATE_MESSAGE:           return handleGroupCallUpdateMessage(currentState, GroupCallUpdateMetadata.fromIntent(intent));
+      case ACTION_GROUP_CALL_PEEK:                     return handleGroupCallPeek(currentState, getRemotePeer(intent));
 
       case ACTION_HTTP_SUCCESS:                        return handleHttpSuccess(currentState, HttpData.fromIntent(intent));
       case ACTION_HTTP_FAILURE:                        return handleHttpFailure(currentState, HttpData.fromIntent(intent));
@@ -727,6 +729,11 @@ public abstract class WebRtcActionProcessor {
     return currentState;
   }
 
+  protected @NonNull WebRtcServiceState handleGroupCallPeek(@NonNull WebRtcServiceState currentState, @NonNull RemotePeer remotePeer) {
+    webRtcInteractor.peekGroupCall(remotePeer.getId());
+    return currentState;
+  }
+
   //endregion
 
   protected @NonNull WebRtcServiceState handleHttpSuccess(@NonNull WebRtcServiceState currentState, @NonNull HttpData httpData) {

app/src/main/java/org/thoughtcrime/securesms/service/webrtc/WebRtcInteractor.java

@@ -94,8 +94,8 @@ public class WebRtcInteractor {
     webRtcCallService.sendGroupCallMessage(recipient, groupCallEraId);
   }
 
-  void updateGroupCallUpdateMessage(@NonNull RecipientId groupId, @Nullable String groupCallEraId, @NonNull Collection<UUID> joinedMembers) {
+  void updateGroupCallUpdateMessage(@NonNull RecipientId groupId, @Nullable String groupCallEraId, @NonNull Collection<UUID> joinedMembers, boolean isCallFull) {
-    webRtcCallService.updateGroupCallUpdateMessage(groupId, groupCallEraId, joinedMembers);
+    webRtcCallService.updateGroupCallUpdateMessage(groupId, groupCallEraId, joinedMembers, isCallFull);
   }
 
   void setCallInProgressNotification(int type, @NonNull RemotePeer remotePeer) {
@@ -157,4 +157,8 @@ public class WebRtcInteractor {
   void peekGroupCall(@NonNull WebRtcData.GroupCallUpdateMetadata groupCallUpdateMetadata) {
     webRtcCallService.peekGroupCall(groupCallUpdateMetadata);
   }
+
+  void peekGroupCall(@NonNull RecipientId recipientId) {
+    webRtcCallService.peekGroupCall(recipientId);
+  }
 }

app/src/main/java/org/thoughtcrime/securesms/service/webrtc/WebRtcUtil.java

@@ -77,4 +77,8 @@ public final class WebRtcUtil {
     PeekInfo peekInfo = groupCall.getPeekInfo();
     return peekInfo != null ? peekInfo.getEraId() : null;
   }
+
+  public static boolean isCallFull(@Nullable PeekInfo peekInfo) {
+    return peekInfo != null && peekInfo.getMaxDevices() != null && peekInfo.getDeviceCount() >= peekInfo.getMaxDevices();
+  }
 }

app/src/main/proto/Database.proto

@@ -75,4 +75,5 @@ message GroupCallUpdateDetails {
              string startedCallUuid      = 2;
              int64  startedCallTimestamp = 3;
     repeated string inCallUuids          = 4;
+             bool   isCallFull           = 5;
 }

app/src/main/res/drawable/ic_video_solid_18.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="18dp"
+    android:height="18dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+  <path
+      android:fillColor="#FFFFFFFF"
+      android:pathData="M23,8.563v6.874a1,1 0,0 1,-1.419 0.908L18.5,14.923V9.077l3.081,-1.422A1,1 0,0 1,23 8.563ZM2.535,4.876A2.639,2.639 0,0 0,1.4 5.939,3.854 3.854,0 0,0 1,8.105V15.9a3.854,3.854 0,0 0,0.4 2.166,2.639 2.639,0 0,0 1.134,1.063 4.6,4.6 0,0 0,2.311 0.376h8.308a4.6,4.6 0,0 0,2.311 -0.376A2.639,2.639 0,0 0,16.6 18.061,3.854 3.854,0 0,0 17,15.9V8.105a3.854,3.854 0,0 0,-0.4 -2.166,2.639 2.639,0 0,0 -1.134,-1.063A4.6,4.6 0,0 0,13.154 4.5H4.846A4.6,4.6 0,0 0,2.535 4.876Z"/>
+</vector>

app/src/main/res/layout/conversation_activity.xml

@@ -22,7 +22,33 @@
             app:contentInsetStart="46dp"
             tools:background="#ff007f00">
 
-            <include layout="@layout/conversation_title_view" />
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:orientation="horizontal">
+
+                <include layout="@layout/conversation_title_view"
+                    android:layout_height="match_parent"
+                    android:layout_width="0dp"
+                    android:layout_weight="1"/>
+
+                <com.google.android.material.button.MaterialButton
+                    android:id="@+id/conversation_group_cal_join"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:fontFamily="sans-serif-medium"
+                    android:text="@string/ConversationActivity_join"
+                    android:textAllCaps="false"
+                    android:visibility="gone"
+                    app:backgroundTint="@color/core_white"
+                    app:cornerRadius="1000dp"
+                    app:icon="@drawable/ic_video_solid_18"
+                    app:iconGravity="textStart"
+                    tools:iconTint="@color/core_ultramarine"
+                    tools:textColor="@color/core_ultramarine"
+                    tools:visibility="visible" />
+
+            </LinearLayout>
 
         </androidx.appcompat.widget.Toolbar>
     </com.google.android.material.appbar.AppBarLayout>

app/src/main/res/layout/conversation_title_view.xml

@@ -7,7 +7,8 @@
     android:layout_height="match_parent"
     android:layout_gravity="center_vertical"
     android:gravity="center_vertical"
-    tools:background="#007fff">
+    tools:background="#007fff"
+    tools:layout_height="?actionBarSize">
 
     <org.thoughtcrime.securesms.components.AvatarImageView
         android:id="@+id/contact_photo_image"

app/src/main/res/values/strings.xml

@@ -298,6 +298,9 @@
 
     <string name="ConversationActivity__more_options_now_in_group_settings">More options now in \"Group settings\"</string>
 
+    <string name="ConversationActivity_join">Join</string>
+    <string name="ConversationActivity_full">Full</string>
+
     <!-- ConversationAdapter -->
     <plurals name="ConversationAdapter_n_unread_messages">
         <item quantity="one">%d unread message</item>
@@ -1924,6 +1927,7 @@
     <string name="ConversationUpdateItem_learn_more">Learn more</string>
     <string name="ConversationUpdateItem_join_call">Join call</string>
     <string name="ConversationUpdateItem_return_to_call">Return to call</string>
+    <string name="ConversationUpdateItem_call_is_full">Call is full</string>
 
     <!-- audio_view -->
     <string name="audio_view__play_pause_accessibility_description">Play … Pause</string>