Discard session command only encrypted room

vector/src/main/java/im/vector/riotx/features/command/Command.kt

@@ -44,7 +44,7 @@ enum class Command(val command: String, val parameters: String, @StringRes val d
     POLL("/poll", "Question | Option 1 | Option 2 ...", R.string.command_description_poll),
     SHRUG("/shrug", "<message>", R.string.command_description_shrug),
     PLAIN("/plain", "<message>", R.string.command_description_plain),
-    DISCARD_SESSION("/discardsession", "<message>", R.string.command_description_discard_session),
+    DISCARD_SESSION("/discardsession","", R.string.command_description_discard_session),
     // TODO temporary command
     VERIFY_USER("/verify", "<user-id>", R.string.command_description_verify);
 

vector/src/main/java/im/vector/riotx/features/home/room/detail/RoomDetailViewModel.kt

@@ -448,7 +448,17 @@ class RoomDetailViewModel @AssistedInject constructor(
                             _viewEvents.post(RoomDetailViewEvents.SlashCommandNotImplemented)
                         }
                         is ParsedCommand.DiscardSession           -> {
-                            session.cryptoService().discardOutbundSession(room.roomId)
+                            if (room.isEncrypted()) {
+                                session.cryptoService().discardOutbundSession(room.roomId)
+                                _viewEvents.post(RoomDetailViewEvents.SlashCommandHandled())
+                                popDraft()
+                            } else {
+                                _viewEvents.post(RoomDetailViewEvents.SlashCommandHandled())
+                                _viewEvents.post(
+                                        RoomDetailViewEvents
+                                                .ShowMessage(stringProvider.getString(R.string.command_description_discard_session_not_handled))
+                                )
+                            }
                         }
                     }.exhaustive
                 }

vector/src/main/res/values/strings_riotX.xml

@@ -7,6 +7,7 @@
 
     <!-- BEGIN Strings added by Valere -->
     <string name="command_description_discard_session">Forces the current outbound group session in an encrypted room to be discarded</string>
+    <string name="command_description_discard_session_not_handled">Only supported in encrypted rooms</string>
     <!-- END Strings added by Valere -->