Show different messages based on join group link error header.

app/src/main/java/org/thoughtcrime/securesms/groups/GroupManagerV2.java

@@ -1041,7 +1041,7 @@ final class GroupManagerV2 {
         throw new GroupChangeFailedException(e);
       } catch (AuthorizationFailedException e) {
         Log.w(TAG, e);
-        throw new GroupLinkNotActiveException(e);
+        throw new GroupLinkNotActiveException(e, Optional.absent());
       }
     }
 

app/src/main/java/org/thoughtcrime/securesms/groups/ui/invitesandrequests/joining/FetchGroupDetailsError.java

@@ -2,5 +2,6 @@ package org.thoughtcrime.securesms.groups.ui.invitesandrequests.joining;
 
 enum FetchGroupDetailsError {
   GroupLinkNotActive,
+  BannedFromGroup,
   NetworkError
 }

app/src/main/java/org/thoughtcrime/securesms/groups/ui/invitesandrequests/joining/GroupJoinBottomSheetDialogFragment.java

@@ -127,10 +127,7 @@ public final class GroupJoinBottomSheetDialogFragment extends BottomSheetDialogF
 
     viewModel.isBusy().observe(getViewLifecycleOwner(), isBusy -> busy.setVisibility(isBusy ? View.VISIBLE : View.GONE));
 
-    viewModel.getErrors().observe(getViewLifecycleOwner(), error -> {
-      Toast.makeText(requireContext(), errorToMessage(error), Toast.LENGTH_SHORT).show();
-      dismiss();
-    });
+    viewModel.getErrors().observe(getViewLifecycleOwner(), this::showError);
 
     viewModel.getJoinErrors().observe(getViewLifecycleOwner(), error -> Toast.makeText(requireContext(), errorToMessage(error), Toast.LENGTH_SHORT).show());
 
@@ -156,16 +153,34 @@ public final class GroupJoinBottomSheetDialogFragment extends BottomSheetDialogF
                                  () -> GroupDescriptionDialog.show(getChildFragmentManager(), name, description, true));
   }
 
-  private @NonNull String errorToMessage(@NonNull FetchGroupDetailsError error) {
-    if (error == FetchGroupDetailsError.GroupLinkNotActive) {
-      return getString(R.string.GroupJoinBottomSheetDialogFragment_this_group_link_is_not_active);
+  private void showError(FetchGroupDetailsError error) {
+    avatar.setVisibility(View.INVISIBLE);
+    groupCancelButton.setVisibility(View.GONE);
+    groupDetails.setVisibility(View.VISIBLE);
+    groupJoinButton.setVisibility(View.VISIBLE);
+    groupJoinButton.setText(getString(android.R.string.ok));
+    groupJoinButton.setOnClickListener(v -> dismissAllowingStateLoss());
+
+    switch (error) {
+      case GroupLinkNotActive:
+        groupName.setText(R.string.GroupJoinBottomSheetDialogFragment_cant_join_group);
+        groupDetails.setText(R.string.GroupJoinBottomSheetDialogFragment_this_group_link_is_no_longer_valid);
+        break;
+      case BannedFromGroup:
+        groupName.setText(R.string.GroupJoinBottomSheetDialogFragment_cant_join_group);
+        groupDetails.setText(R.string.GroupJoinBottomSheetDialogFragment_you_cant_join_this_group_via_the_group_link_because_an_admin_removed_you);
+        break;
+      case NetworkError:
+        groupName.setText(R.string.GroupJoinBottomSheetDialogFragment_link_error);
+        groupDetails.setText(R.string.GroupJoinBottomSheetDialogFragment_joining_via_this_link_failed_try_joining_again_later);
+        break;
     }
-    return getString(R.string.GroupJoinBottomSheetDialogFragment_unable_to_get_group_information_please_try_again_later);
   }
 
   private @NonNull String errorToMessage(@NonNull JoinGroupError error) {
     switch (error) {
       case GROUP_LINK_NOT_ACTIVE: return getString(R.string.GroupJoinBottomSheetDialogFragment_this_group_link_is_not_active);
+      case BANNED               : return getString(R.string.GroupJoinBottomSheetDialogFragment_you_cant_join_this_group_via_the_group_link_because_an_admin_removed_you);
       case NETWORK_ERROR        : return getString(R.string.GroupJoinBottomSheetDialogFragment_encountered_a_network_error);
       default                   : return getString(R.string.GroupJoinBottomSheetDialogFragment_unable_to_join_group_please_try_again_later);
     }

app/src/main/java/org/thoughtcrime/securesms/groups/ui/invitesandrequests/joining/GroupJoinRepository.java

@@ -39,7 +39,9 @@ final class GroupJoinRepository {
         callback.onComplete(getGroupDetails());
       } catch (IOException e) {
         callback.onError(FetchGroupDetailsError.NetworkError);
-      } catch (VerificationFailedException | GroupLinkNotActiveException e) {
+      } catch (GroupLinkNotActiveException e) {
+        callback.onError(e.getReason() == GroupLinkNotActiveException.Reason.BANNED ? FetchGroupDetailsError.BannedFromGroup : FetchGroupDetailsError.GroupLinkNotActive);
+      } catch (VerificationFailedException e) {
         callback.onError(FetchGroupDetailsError.GroupLinkNotActive);
       }
     });
@@ -62,7 +64,7 @@ final class GroupJoinRepository {
       } catch (GroupChangeBusyException e) {
         callback.onError(JoinGroupError.BUSY);
       } catch (GroupLinkNotActiveException e) {
-        callback.onError(JoinGroupError.GROUP_LINK_NOT_ACTIVE);
+        callback.onError(e.getReason() == GroupLinkNotActiveException.Reason.BANNED ? JoinGroupError.BANNED : JoinGroupError.GROUP_LINK_NOT_ACTIVE);
       } catch (GroupChangeFailedException | MembershipNotSuitableForV2Exception e) {
         callback.onError(JoinGroupError.FAILED);
       }

app/src/main/java/org/thoughtcrime/securesms/groups/ui/invitesandrequests/joining/JoinGroupError.java

@@ -3,6 +3,7 @@ package org.thoughtcrime.securesms.groups.ui.invitesandrequests.joining;
 enum JoinGroupError {
   BUSY,
   GROUP_LINK_NOT_ACTIVE,
+  BANNED,
   FAILED,
   NETWORK_ERROR,
 }

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

@@ -44,8 +44,11 @@
     <TextView
         android:id="@+id/group_join_group_details"
         style="@style/Signal.Text.Body"
-        android:layout_width="wrap_content"
+        android:layout_width="0dp"
         android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginEnd="16dp"
+        android:gravity="center_horizontal"
         android:textColor="@color/signal_text_secondary"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintHorizontal_bias="0.5"
@@ -95,7 +98,6 @@
         android:layout_height="64dp"
         android:layout_marginStart="16dp"
         android:layout_marginTop="8dp"
-        android:layout_marginEnd="16dp"
         android:layout_marginBottom="16dp"
         android:text="@android:string/cancel"
         android:visibility="invisible"
@@ -112,7 +114,7 @@
         style="@style/Button.Primary"
         android:layout_width="0dp"
         android:layout_height="64dp"
-        android:layout_marginStart="0dp"
+        android:layout_marginStart="16dp"
         android:layout_marginTop="8dp"
         android:layout_marginEnd="16dp"
         android:layout_marginBottom="16dp"

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

@@ -873,8 +873,17 @@
     <string name="GroupJoinBottomSheetDialogFragment_unable_to_join_group_please_try_again_later">Unable to join group. Please try again later</string>
     <string name="GroupJoinBottomSheetDialogFragment_encountered_a_network_error">Encountered a network error.</string>
     <string name="GroupJoinBottomSheetDialogFragment_this_group_link_is_not_active">This group link is not active</string>
+    <!-- Title shown when there was an known issue getting group information from a group link -->
+    <string name="GroupJoinBottomSheetDialogFragment_cant_join_group">Can\'t join group</string>
+    <!-- Message shown when you try to get information for a group via link but an admin has removed you -->
+    <string name="GroupJoinBottomSheetDialogFragment_you_cant_join_this_group_via_the_group_link_because_an_admin_removed_you">You can\'t join this group via the group link because an admin removed you.</string>
+    <!-- Message shown when you try to get information for a group via link but the link is no longer valid -->
+    <string name="GroupJoinBottomSheetDialogFragment_this_group_link_is_no_longer_valid">This group link is no longer valid.</string>
+    <!-- Title shown when there was an unknown issue getting group information from a group link -->
+    <string name="GroupJoinBottomSheetDialogFragment_link_error">Link error</string>
+    <!-- Message shown when you try to get information for a group via link but an unknown issue occurred -->
+    <string name="GroupJoinBottomSheetDialogFragment_joining_via_this_link_failed_try_joining_again_later">Joining via this link failed. Try joining again later.</string>
 
-    <string name="GroupJoinBottomSheetDialogFragment_unable_to_get_group_information_please_try_again_later">Unable to get group information, please try again later</string>
     <string name="GroupJoinBottomSheetDialogFragment_direct_join">Do you want to join this group and share your name and photo with its members?</string>
     <string name="GroupJoinBottomSheetDialogFragment_admin_approval_needed">An admin of this group must approve your request before you can join this group. When you request to join, your name and photo will be shared with its members.</string>
     <plurals name="GroupJoinBottomSheetDialogFragment_group_dot_d_members">

libsignal/service/src/main/java/org/whispersystems/signalservice/api/groupsv2/GroupLinkNotActiveException.java

@@ -1,16 +1,34 @@
 package org.whispersystems.signalservice.api.groupsv2;
 
+import org.whispersystems.libsignal.util.guava.Optional;
+
 /**
  * Thrown when a group link:
  * - has an out of date password, or;
  * - is currently not shared, or;
+ * - has been banned from the group, or;
  * - the master key does not match a group on the server
  */
 public final class GroupLinkNotActiveException extends Exception {
-  public GroupLinkNotActiveException() {
+
+  private final Reason reason;
+
+  public GroupLinkNotActiveException(Throwable t, Optional<String> reason) {
+    super(t);
+
+    if (reason.isPresent() && reason.get().equalsIgnoreCase("banned")) {
+      this.reason = Reason.BANNED;
+    } else {
+      this.reason = Reason.UNKNOWN;
+    }
   }
 
-  public GroupLinkNotActiveException(Throwable t) {
-    super(t);
+  public Reason getReason() {
+    return reason;
+  }
+
+  public enum Reason {
+    UNKNOWN,
+    BANNED
   }
 }

libsignal/service/src/main/java/org/whispersystems/signalservice/api/groupsv2/GroupsV2Api.java

@@ -134,7 +134,7 @@ public class GroupsV2Api {
 
       return groupOperations.decryptGroupJoinInfo(joinInfo);
     } catch (ForbiddenException e) {
-      throw new GroupLinkNotActiveException();
+      throw new GroupLinkNotActiveException(null, e.getReason());
     }
   }
 

libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java

@@ -36,6 +36,7 @@ import org.whispersystems.libsignal.state.PreKeyBundle;
 import org.whispersystems.libsignal.state.PreKeyRecord;
 import org.whispersystems.libsignal.state.SignedPreKeyRecord;
 import org.whispersystems.libsignal.util.Pair;
+import org.whispersystems.libsignal.util.guava.Function;
 import org.whispersystems.libsignal.util.guava.Optional;
 import org.whispersystems.signalservice.api.account.AccountAttributes;
 import org.whispersystems.signalservice.api.account.ChangePhoneNumberRequest;
@@ -1968,7 +1969,7 @@ public class PushServiceSocket {
 
     ResponseBody responseBody = response.body();
     try {
-      responseCodeHandler.handle(response.code(), responseBody);
+      responseCodeHandler.handle(response.code(), responseBody, response::header);
 
       switch (response.code()) {
         case 204:
@@ -2293,6 +2294,10 @@ public class PushServiceSocket {
 
   private interface ResponseCodeHandler {
     void handle(int responseCode, ResponseBody body) throws NonSuccessfulResponseCodeException, PushNetworkException;
+
+    default void handle(int responseCode, ResponseBody body, Function<String, String> getHeader) throws NonSuccessfulResponseCodeException, PushNetworkException {
+      handle(responseCode, body);
+    }
   }
 
   private static class EmptyResponseCodeHandler implements ResponseCodeHandler {
@@ -2328,8 +2333,18 @@ public class PushServiceSocket {
   private static final ResponseCodeHandler GROUPS_V2_PATCH_RESPONSE_HANDLER = (responseCode, body) -> {
     if (responseCode == 400) throw new GroupPatchNotAcceptedException();
   };
-  private static final ResponseCodeHandler GROUPS_V2_GET_JOIN_INFO_HANDLER  = (responseCode, body) -> {
-    if (responseCode == 403) throw new ForbiddenException();
+  private static final ResponseCodeHandler GROUPS_V2_GET_JOIN_INFO_HANDLER  = new ResponseCodeHandler() {
+    @Override
+    public void handle(int responseCode, ResponseBody body) throws NonSuccessfulResponseCodeException {
+      if (responseCode == 403) throw new ForbiddenException();
+    }
+
+    @Override
+    public void handle(int responseCode, ResponseBody body, Function<String, String> getHeader) throws NonSuccessfulResponseCodeException {
+      if (responseCode == 403) {
+        throw new ForbiddenException(Optional.fromNullable(getHeader.apply("X-Signal-Forbidden-Reason")));
+      }
+    }
   };
 
   public void putNewGroupsV2Group(Group group, GroupsV2AuthorizationString authorization)

libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/exceptions/ForbiddenException.java

@@ -1,9 +1,21 @@
 package org.whispersystems.signalservice.internal.push.exceptions;
 
+import org.whispersystems.libsignal.util.guava.Optional;
 import org.whispersystems.signalservice.api.push.exceptions.NonSuccessfulResponseCodeException;
 
 public final class ForbiddenException extends NonSuccessfulResponseCodeException {
+  private Optional<String> reason;
+
   public ForbiddenException() {
+    this(Optional.absent());
+  }
+
+  public ForbiddenException(Optional<String> reason) {
     super(403);
+    this.reason = reason;
+  }
+
+  public Optional<String> getReason() {
+    return reason;
   }
 }