Show groups that have the same member list during group creation.

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/labs/LabsSettingsEvents.kt

@@ -9,4 +9,5 @@ sealed interface LabsSettingsEvents {
   data class ToggleIndividualChatPlaintextExport(val enabled: Boolean) : LabsSettingsEvents
   data class ToggleStoryArchive(val enabled: Boolean) : LabsSettingsEvents
   data class ToggleIncognito(val enabled: Boolean) : LabsSettingsEvents
+  data class ToggleGroupSuggestionsForMembers(val enabled: Boolean) : LabsSettingsEvents
 }

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/labs/LabsSettingsFragment.kt

@@ -115,6 +115,15 @@ private fun LabsSettingsContent(
           onCheckChanged = { onEvent(LabsSettingsEvents.ToggleIncognito(it)) }
         )
       }
+
+      item {
+        Rows.ToggleRow(
+          checked = state.groupSuggestionsForMembers,
+          text = "Group Suggestions for Members",
+          label = "When creating a group, show existing groups that have the exact same members.",
+          onCheckChanged = { onEvent(LabsSettingsEvents.ToggleGroupSuggestionsForMembers(it)) }
+        )
+      }
     }
   }
 }

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/labs/LabsSettingsState.kt

@@ -11,5 +11,6 @@ import androidx.compose.runtime.Immutable
 data class LabsSettingsState(
   val individualChatPlaintextExport: Boolean = false,
   val storyArchive: Boolean = false,
-  val incognito: Boolean = false
+  val incognito: Boolean = false,
+  val groupSuggestionsForMembers: Boolean = false
 )

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/labs/LabsSettingsViewModel.kt

@@ -29,6 +29,10 @@ class LabsSettingsViewModel : ViewModel() {
         SignalStore.labs.incognito = event.enabled
         _state.value = _state.value.copy(incognito = event.enabled)
       }
+      is LabsSettingsEvents.ToggleGroupSuggestionsForMembers -> {
+        SignalStore.labs.groupSuggestionsForMembers = event.enabled
+        _state.value = _state.value.copy(groupSuggestionsForMembers = event.enabled)
+      }
     }
   }
 
@@ -36,7 +40,8 @@ class LabsSettingsViewModel : ViewModel() {
     return LabsSettingsState(
       individualChatPlaintextExport = SignalStore.labs.individualChatPlaintextExport,
       storyArchive = SignalStore.labs.storyArchive,
-      incognito = SignalStore.labs.incognito
+      incognito = SignalStore.labs.incognito,
+      groupSuggestionsForMembers = SignalStore.labs.groupSuggestionsForMembers
     )
   }
 }

app/src/main/java/org/thoughtcrime/securesms/database/GroupTable.kt

@@ -506,6 +506,17 @@ class GroupTable(context: Context?, databaseHelper: SignalDatabase?) :
       }
   }
 
+  @WorkerThread
+  fun getGroupsWithExactMembers(memberIds: Set<RecipientId>): List<GroupRecord> {
+    if (memberIds.isEmpty()) return emptyList()
+
+    val selfId = Recipient.self().id
+    val expectedMembers = if (selfId in memberIds) memberIds else memberIds + selfId
+
+    return getGroupsContainingMember(selfId, pushOnly = true, includeInactive = false)
+      .filter { it.members.toSet() == expectedMembers }
+  }
+
   fun getGroups(): Reader {
     val cursor = readableDatabase.query(joinedGroupSelect())
     return Reader(cursor)

app/src/main/java/org/thoughtcrime/securesms/groups/ui/creategroup/details/AddGroupDetailsFragment.java

@@ -29,12 +29,16 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
 import com.bumptech.glide.request.target.CustomTarget;
 import com.bumptech.glide.request.transition.Transition;
+import com.bumptech.glide.RequestManager;
+import com.google.android.material.chip.ChipGroup;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 
 import org.signal.core.util.EditTextUtil;
 import org.signal.core.ui.logging.LoggingFragment;
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.avatar.picker.AvatarPickerFragment;
+import org.thoughtcrime.securesms.contacts.ContactChip;
+import org.thoughtcrime.securesms.conversation.ConversationIntents;
 import org.thoughtcrime.securesms.components.settings.app.privacy.expire.ExpireTimerSettingsFragment;
 import org.thoughtcrime.securesms.groups.ui.GroupMemberListView;
 import org.thoughtcrime.securesms.keyvalue.SignalStore;
@@ -150,6 +154,29 @@ public class AddGroupDetailsFragment extends LoggingFragment {
       startActivityForResult(RecipientDisappearingMessagesActivity.forCreateGroup(requireContext(), viewModel.getDisappearingMessagesTimer().getValue()), REQUEST_DISAPPEARING_TIMER);
     });
 
+    View      sameGroupsSection   = view.findViewById(R.id.same_groups_section);
+    ChipGroup sameGroupsChipGroup = view.findViewById(R.id.same_groups_chip_group);
+
+    if (SignalStore.labs().getGroupSuggestionsForMembers()) {
+      viewModel.getSameGroups().observe(getViewLifecycleOwner(), groups -> {
+        sameGroupsChipGroup.removeAllViews();
+        if (groups.isEmpty()) {
+          sameGroupsSection.setVisibility(View.GONE);
+        } else {
+          sameGroupsSection.setVisibility(View.VISIBLE);
+          RequestManager requestManager = Glide.with(this);
+          for (Recipient group : groups) {
+            ContactChip chip = new ContactChip(requireContext());
+            chip.setText(group.getDisplayName(requireContext()));
+            chip.setAvatar(requestManager, group, null);
+            chip.setCloseIconVisible(false);
+            chip.setOnClickListener(v -> navigateToConversation(group.getId()));
+            sameGroupsChipGroup.addView(chip);
+          }
+        }
+      });
+    }
+
     name.requestFocus();
 
     getParentFragmentManager().setFragmentResultListener(AvatarPickerFragment.REQUEST_KEY_SELECT_AVATAR,
@@ -266,6 +293,14 @@ public class AddGroupDetailsFragment extends LoggingFragment {
     create.setEnabled(isEnabled);
   }
 
+  private void navigateToConversation(@NonNull RecipientId groupRecipientId) {
+    ConversationIntents.createBuilder(requireContext(), groupRecipientId, -1L)
+                       .subscribe(builder -> {
+                         startActivity(builder.build());
+                         requireActivity().finish();
+                       });
+  }
+
   private void showAvatarPicker() {
     Media media = viewModel.getAvatarMedia();
 

app/src/main/java/org/thoughtcrime/securesms/groups/ui/creategroup/details/AddGroupDetailsRepository.java

@@ -8,6 +8,8 @@ import androidx.core.util.Consumer;
 
 import org.signal.core.util.concurrent.SignalExecutors;
 import org.signal.core.util.logging.Log;
+import org.thoughtcrime.securesms.database.SignalDatabase;
+import org.thoughtcrime.securesms.database.model.GroupRecord;
 import org.thoughtcrime.securesms.groups.GroupChangeBusyException;
 import org.thoughtcrime.securesms.groups.GroupChangeException;
 import org.thoughtcrime.securesms.groups.GroupManager;
@@ -44,6 +46,19 @@ final class AddGroupDetailsRepository {
     });
   }
 
+  void getGroupsWithSameMembers(@NonNull Set<RecipientId> memberIds, Consumer<List<Recipient>> consumer) {
+    SignalExecutors.BOUNDED.execute(() -> {
+      List<GroupRecord> groups     = SignalDatabase.groups().getGroupsWithExactMembers(memberIds);
+      List<Recipient>   recipients = new ArrayList<>(groups.size());
+
+      for (GroupRecord group : groups) {
+        recipients.add(Recipient.resolved(group.getRecipientId()));
+      }
+
+      consumer.accept(recipients);
+    });
+  }
+
   void createGroup(@NonNull Set<RecipientId> members,
                    @Nullable byte[] avatar,
                    @Nullable String name,

app/src/main/java/org/thoughtcrime/securesms/groups/ui/creategroup/details/AddGroupDetailsViewModel.java

@@ -16,6 +16,7 @@ import com.annimon.stream.Stream;
 import org.thoughtcrime.securesms.groups.ui.GroupMemberEntry;
 import org.thoughtcrime.securesms.keyvalue.SignalStore;
 import org.signal.core.models.media.Media;
+import org.thoughtcrime.securesms.recipients.Recipient;
 import org.thoughtcrime.securesms.recipients.RecipientId;
 import org.thoughtcrime.securesms.util.DefaultValueLiveData;
 import org.thoughtcrime.securesms.util.SingleLiveEvent;
@@ -38,6 +39,7 @@ public final class AddGroupDetailsViewModel extends ViewModel {
   private final MutableLiveData<Integer>                           disappearingMessagesTimer = new MutableLiveData<>(SignalStore.settings().getUniversalExpireTimer());
   private final LiveData<Boolean>                                  isMms;
   private final LiveData<Boolean>                                  canSubmitForm;
+  private final LiveData<List<Recipient>>                           sameGroups;
   private final AddGroupDetailsRepository                          repository;
 
   private Media avatarMedia;
@@ -53,6 +55,16 @@ public final class AddGroupDetailsViewModel extends ViewModel {
     members       = LiveDataUtil.combineLatest(initialMembers, deleted, AddGroupDetailsViewModel::filterDeletedMembers);
     isMms         = Transformations.map(members, AddGroupDetailsViewModel::isAnyForcedSms);
     canSubmitForm = LiveDataUtil.combineLatest(isMms, isValidName, (mms, validName) -> mms || validName);
+    sameGroups    = Transformations.switchMap(members, memberList -> {
+      MutableLiveData<List<Recipient>> result = new MutableLiveData<>(Collections.emptyList());
+      if (!memberList.isEmpty()) {
+        Set<RecipientId> memberIds = Stream.of(memberList)
+                                          .map(member -> member.getMember().getId())
+                                          .collect(Collectors.toSet());
+        repository.getGroupsWithSameMembers(memberIds, result::postValue);
+      }
+      return result;
+    });
 
     repository.resolveMembers(recipientIds, initialMembers::postValue);
   }
@@ -77,6 +89,10 @@ public final class AddGroupDetailsViewModel extends ViewModel {
     return isMms;
   }
 
+  @NonNull LiveData<List<Recipient>> getSameGroups() {
+    return sameGroups;
+  }
+
   @NonNull LiveData<Integer> getDisappearingMessagesTimer() {
     return disappearingMessagesTimer;
   }

app/src/main/java/org/thoughtcrime/securesms/keyvalue/LabsValues.kt

@@ -7,6 +7,7 @@ class LabsValues internal constructor(store: KeyValueStore) : SignalStoreValues(
     const val INDIVIDUAL_CHAT_PLAINTEXT_EXPORT: String = "labs.individual_chat_plaintext_export"
     const val STORY_ARCHIVE: String = "labs.story_archive"
     const val INCOGNITO: String = "labs.incognito"
+    const val GROUP_SUGGESTIONS_FOR_MEMBERS: String = "labs.group_suggestions_for_members"
   }
 
   public override fun onFirstEverAppLaunch() = Unit
@@ -19,6 +20,8 @@ class LabsValues internal constructor(store: KeyValueStore) : SignalStoreValues(
 
   var incognito by booleanValue(INCOGNITO, true).falseForExternalUsers()
 
+  var groupSuggestionsForMembers by booleanValue(GROUP_SUGGESTIONS_FOR_MEMBERS, true).falseForExternalUsers()
+
   private fun SignalStoreValueDelegate<Boolean>.falseForExternalUsers(): SignalStoreValueDelegate<Boolean> {
     return this.map { actualValue -> RemoteConfig.internalUser && actualValue }
   }

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

@@ -98,7 +98,7 @@
         android:layout_marginEnd="@dimen/dsl_settings_gutter"
         android:orientation="vertical"
         android:visibility="gone"
-        app:layout_constraintBottom_toTopOf="@id/member_list_header"
+        app:layout_constraintBottom_toTopOf="@id/same_groups_section"
         app:layout_constraintTop_toBottomOf="@id/divider"
         app:layout_goneMarginTop="23dp"
         tools:visibility="visible">
@@ -118,6 +118,43 @@
 
     </LinearLayout>
 
+    <LinearLayout
+        android:id="@+id/same_groups_section"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="vertical"
+        android:visibility="gone"
+        app:layout_constraintTop_toBottomOf="@id/mms_warning"
+        tools:visibility="visible">
+
+        <TextView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:gravity="center_vertical"
+            android:minHeight="40dp"
+            android:paddingHorizontal="@dimen/dsl_settings_gutter"
+            android:text="@string/AddGroupDetailsFragment__groups_with_same_members"
+            android:textAppearance="@style/Signal.Text.TitleSmall" />
+
+        <HorizontalScrollView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:clipToPadding="false"
+            android:paddingHorizontal="@dimen/dsl_settings_gutter"
+            android:paddingBottom="8dp"
+            android:scrollbars="none">
+
+            <com.google.android.material.chip.ChipGroup
+                android:id="@+id/same_groups_chip_group"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                app:singleLine="true"
+                app:chipSpacingHorizontal="8dp" />
+
+        </HorizontalScrollView>
+
+    </LinearLayout>
+
     <TextView
         android:id="@+id/member_list_header"
         android:layout_width="match_parent"
@@ -128,7 +165,7 @@
         android:minHeight="52sp"
         android:text="@string/AddGroupDetailsFragment__members"
         android:textAppearance="@style/Signal.Text.TitleSmall"
-        app:layout_constraintTop_toBottomOf="@id/mms_warning" />
+        app:layout_constraintTop_toBottomOf="@id/same_groups_section" />
 
     <TextView
         android:id="@+id/add_later"

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

@@ -9615,5 +9615,8 @@
     <!-- Body for screen shown to let the user know that displaying their member label will take priority over their about text. -->
     <string name="MemberLabelsAboutOverride__body">In this group, your Member Label will be displayed beside your photo in place of your About.</string>
 
+    <!-- Label for internal-only section showing groups with same members -->
+    <string name="AddGroupDetailsFragment__groups_with_same_members" translatable="false">Groups with same members (Internal Only)</string>
+
     <!-- EOF -->
 </resources>