room version cap support + room upgrade

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/homeserver/HomeServerCapabilities.kt

@@ -16,6 +16,8 @@
 
 package org.matrix.android.sdk.api.session.homeserver
 
+import org.matrix.android.sdk.api.session.homeserver.HomeServerCapabilities.Companion.MAX_UPLOAD_FILE_SIZE_UNKNOWN
+
 data class HomeServerCapabilities(
         /**
          * True if it is possible to change the password of the account.
@@ -32,7 +34,9 @@ data class HomeServerCapabilities(
         /**
          * Default identity server url, provided in Wellknown
          */
-        val defaultIdentityServerUrl: String? = null
+        val defaultIdentityServerUrl: String? = null,
+
+        val roomVersions: RoomVersionCapabilities? = null
 ) {
     companion object {
         const val MAX_UPLOAD_FILE_SIZE_UNKNOWN = -1L

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/homeserver/RoomVersionModel.kt

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.api.session.homeserver
+
+data class RoomVersionCapabilities(
+        val defaultRoomVersion: String,
+        val supportedVersion: List<RoomVersionInfo>
+)
+
+data class RoomVersionInfo(
+        val version: String,
+        val status: RoomVersionStatus
+)
+
+enum class RoomVersionStatus {
+    STABLE,
+    UNSTABLE
+}

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/Room.kt

@@ -34,6 +34,7 @@ import org.matrix.android.sdk.api.session.room.tags.TagsService
 import org.matrix.android.sdk.api.session.room.timeline.TimelineService
 import org.matrix.android.sdk.api.session.room.typing.TypingService
 import org.matrix.android.sdk.api.session.room.uploads.UploadsService
+import org.matrix.android.sdk.api.session.room.version.RoomVersionService
 import org.matrix.android.sdk.api.session.search.SearchResult
 import org.matrix.android.sdk.api.session.space.Space
 import org.matrix.android.sdk.api.util.Optional
@@ -57,7 +58,8 @@ interface Room :
         RelationService,
         RoomCryptoService,
         RoomPushRuleService,
-        RoomAccountDataService {
+        RoomAccountDataService,
+        RoomVersionService {
 
     /**
      * The roomId of this room

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/version/RoomVersionService.kt

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.api.session.room.version
+
+interface RoomVersionService {
+
+    fun getRoomVersion(): String
+
+    /**
+     * Upgrade to the given room version
+     * @return the replacement room id
+     */
+    suspend fun upgradeToVersion(version: String): String
+
+    suspend fun getRecommendedVersion() : String
+
+    fun userMayUpgradeRoom(userId: String): Boolean
+}

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/space/Space.kt

@@ -18,6 +18,7 @@ package org.matrix.android.sdk.api.session.space
 
 import org.matrix.android.sdk.api.session.room.Room
 import org.matrix.android.sdk.api.session.room.model.RoomSummary
+import org.matrix.android.sdk.api.session.space.model.SpaceChildContent
 
 interface Space {
 
@@ -38,6 +39,8 @@ interface Space {
                             autoJoin: Boolean = false,
                             suggested: Boolean? = false)
 
+    fun getChildInfo(roomId: String): SpaceChildContent?
+
     suspend fun removeChildren(roomId: String)
 
     @Throws

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/database/RealmSessionStoreMigration.kt

@@ -46,7 +46,7 @@ import javax.inject.Inject
 class RealmSessionStoreMigration @Inject constructor() : RealmMigration {
 
     companion object {
-        const val SESSION_STORE_SCHEMA_VERSION = 14L
+        const val SESSION_STORE_SCHEMA_VERSION = 15L
     }
 
     override fun migrate(realm: DynamicRealm, oldVersion: Long, newVersion: Long) {
@@ -66,6 +66,7 @@ class RealmSessionStoreMigration @Inject constructor() : RealmMigration {
         if (oldVersion <= 11) migrateTo12(realm)
         if (oldVersion <= 12) migrateTo13(realm)
         if (oldVersion <= 13) migrateTo14(realm)
+        if (oldVersion <= 14) migrateTo15(realm)
     }
 
     private fun migrateTo1(realm: DynamicRealm) {
@@ -306,4 +307,10 @@ class RealmSessionStoreMigration @Inject constructor() : RealmMigration {
 
         roomAccountDataSchema.isEmbedded = true
     }
+
+    private fun migrateTo15(realm: DynamicRealm) {
+        Timber.d("Step 14 -> 15")
+        realm.schema.get("HomeServerCapabilitiesEntity")
+                ?.addField(HomeServerCapabilitiesEntityFields.ROOM_VERSION_JSON, String::class.java)
+    }
 }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/database/mapper/HomeServerCapabilitiesMapper.kt

@@ -16,8 +16,15 @@
 
 package org.matrix.android.sdk.internal.database.mapper
 
+import org.matrix.android.sdk.api.extensions.tryOrNull
 import org.matrix.android.sdk.api.session.homeserver.HomeServerCapabilities
+import org.matrix.android.sdk.api.session.homeserver.RoomVersionCapabilities
+import org.matrix.android.sdk.api.session.homeserver.RoomVersionInfo
+import org.matrix.android.sdk.api.session.homeserver.RoomVersionStatus
 import org.matrix.android.sdk.internal.database.model.HomeServerCapabilitiesEntity
+import org.matrix.android.sdk.internal.di.MoshiProvider
+import org.matrix.android.sdk.internal.session.homeserver.RoomVersions
+import org.matrix.android.sdk.internal.session.room.version.DefaultRoomVersionService
 
 /**
  * HomeServerCapabilitiesEntity -> HomeSeverCapabilities
@@ -29,7 +36,21 @@ internal object HomeServerCapabilitiesMapper {
                 canChangePassword = entity.canChangePassword,
                 maxUploadFileSize = entity.maxUploadFileSize,
                 lastVersionIdentityServerSupported = entity.lastVersionIdentityServerSupported,
-                defaultIdentityServerUrl = entity.defaultIdentityServerUrl
+                defaultIdentityServerUrl = entity.defaultIdentityServerUrl,
+                roomVersions = entity.roomVersionJson?.let {
+                    tryOrNull {
+                        MoshiProvider.providesMoshi().adapter(RoomVersions::class.java).fromJson(it)?.let {
+                            RoomVersionCapabilities(
+                                    defaultRoomVersion = it.default ?: DefaultRoomVersionService.DEFAULT_ROOM_VERSION,
+                                    supportedVersion = it.available.entries.map { entry ->
+                                        RoomVersionInfo(entry.key, RoomVersionStatus.STABLE
+                                                .takeIf { entry.value == "stable" }
+                                                ?: RoomVersionStatus.UNSTABLE)
+                                    }
+                            )
+                        }
+                    }
+                }
         )
     }
 }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/database/model/HomeServerCapabilitiesEntity.kt

@@ -24,7 +24,8 @@ internal open class HomeServerCapabilitiesEntity(
         var maxUploadFileSize: Long = HomeServerCapabilities.MAX_UPLOAD_FILE_SIZE_UNKNOWN,
         var lastVersionIdentityServerSupported: Boolean = false,
         var defaultIdentityServerUrl: String? = null,
-        var lastUpdatedTimestamp: Long = 0L
+        var lastUpdatedTimestamp: Long = 0L,
+        var roomVersionJson: String? = null
 ) : RealmObject() {
 
     companion object

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/homeserver/GetCapabilitiesResult.kt

@@ -19,6 +19,7 @@ package org.matrix.android.sdk.internal.session.homeserver
 import com.squareup.moshi.Json
 import com.squareup.moshi.JsonClass
 import org.matrix.android.sdk.api.extensions.orTrue
+import org.matrix.android.sdk.api.util.JsonDict
 
 /**
  * Ref: https://matrix.org/docs/spec/client_server/latest#get-matrix-client-r0-capabilities
@@ -38,9 +39,14 @@ internal data class Capabilities(
          * Capability to indicate if the user can change their password.
          */
         @Json(name = "m.change_password")
-        val changePassword: ChangePassword? = null
+        val changePassword: ChangePassword? = null,
 
-        // No need for m.room_versions for the moment
+        /**
+         * This capability describes the default and available room versions a server supports, and at what level of stability.
+         * Clients should make use of this capability to determine if users need to be encouraged to upgrade their rooms.
+         */
+        @Json(name = "m.room_versions")
+        val roomVersions: RoomVersions? = null
 )
 
 @JsonClass(generateAdapter = true)
@@ -52,6 +58,18 @@ internal data class ChangePassword(
         val enabled: Boolean?
 )
 
+@JsonClass(generateAdapter = true)
+internal data class RoomVersions(
+        /**
+         * Required. True if the user can change their password, false otherwise.
+         */
+        @Json(name = "default")
+        val default: String?,
+
+        @Json(name = "available")
+        val available: JsonDict
+)
+
 // The spec says: If not present, the client should assume that password changes are possible via the API
 internal fun GetCapabilitiesResult.canChangePassword(): Boolean {
     return capabilities?.changePassword?.enabled.orTrue()

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/homeserver/GetHomeServerCapabilitiesTask.kt

@@ -24,6 +24,7 @@ import org.matrix.android.sdk.internal.auth.version.Versions
 import org.matrix.android.sdk.internal.auth.version.isLoginAndRegistrationSupportedBySdk
 import org.matrix.android.sdk.internal.database.model.HomeServerCapabilitiesEntity
 import org.matrix.android.sdk.internal.database.query.getOrCreate
+import org.matrix.android.sdk.internal.di.MoshiProvider
 import org.matrix.android.sdk.internal.di.SessionDatabase
 import org.matrix.android.sdk.internal.di.UserId
 import org.matrix.android.sdk.internal.network.GlobalErrorReceiver
@@ -104,6 +105,10 @@ internal class DefaultGetHomeServerCapabilitiesTask @Inject constructor(
 
             if (getCapabilitiesResult != null) {
                 homeServerCapabilitiesEntity.canChangePassword = getCapabilitiesResult.canChangePassword()
+
+                homeServerCapabilitiesEntity.roomVersionJson = getCapabilitiesResult.capabilities?.roomVersions?.let {
+                    MoshiProvider.providesMoshi().adapter(RoomVersions::class.java).toJson(it)
+                }
             }
 
             if (getMediaConfigResult != null) {

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/DefaultRoom.kt

@@ -37,6 +37,7 @@ import org.matrix.android.sdk.api.session.room.tags.TagsService
 import org.matrix.android.sdk.api.session.room.timeline.TimelineService
 import org.matrix.android.sdk.api.session.room.typing.TypingService
 import org.matrix.android.sdk.api.session.room.uploads.UploadsService
+import org.matrix.android.sdk.api.session.room.version.RoomVersionService
 import org.matrix.android.sdk.api.session.search.SearchResult
 import org.matrix.android.sdk.api.session.space.Space
 import org.matrix.android.sdk.api.util.Optional
@@ -69,7 +70,8 @@ internal class DefaultRoom(override val roomId: String,
                            private val roomAccountDataService: RoomAccountDataService,
                            private val sendStateTask: SendStateTask,
                            private val viaParameterFinder: ViaParameterFinder,
-                           private val searchTask: SearchTask) :
+                           private val searchTask: SearchTask,
+                           private val roomVersionService: RoomVersionService) :
         Room,
         TimelineService by timelineService,
         SendService by sendService,
@@ -85,7 +87,8 @@ internal class DefaultRoom(override val roomId: String,
         RelationService by relationService,
         MembershipService by roomMembersService,
         RoomPushRuleService by roomPushRuleService,
-        RoomAccountDataService by roomAccountDataService {
+        RoomAccountDataService by roomAccountDataService,
+        RoomVersionService by roomVersionService {
 
     override fun getRoomSummaryLive(): LiveData<Optional<RoomSummary>> {
         return roomSummaryDataSource.getRoomSummaryLive(roomId)

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/RoomAPI.kt

@@ -369,4 +369,15 @@ internal interface RoomAPI {
                                    @Path("roomId") roomId: String,
                                    @Path("type") type: String,
                                    @Body content: JsonDict)
+
+    /**
+     * Upgrades the given room to a particular room version.
+     * Errors:
+     * 400, The request was invalid. One way this can happen is if the room version requested is not supported by the homeserver
+     * (M_UNSUPPORTED_ROOM_VERSION)
+     * 403: The user is not permitted to upgrade the room.(M_FORBIDDEN)
+     */
+    @POST(NetworkConstants.URI_API_PREFIX_PATH_R0 + "rooms/{roomId}/upgrade")
+    suspend fun upgradeRoom(@Path("roomId") roomId: String,
+                            @Body body: RoomUpgradeBody): RoomUpgradeResponse
 }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/RoomFactory.kt

@@ -37,6 +37,7 @@ import org.matrix.android.sdk.internal.session.room.tags.DefaultTagsService
 import org.matrix.android.sdk.internal.session.room.timeline.DefaultTimelineService
 import org.matrix.android.sdk.internal.session.room.typing.DefaultTypingService
 import org.matrix.android.sdk.internal.session.room.uploads.DefaultUploadsService
+import org.matrix.android.sdk.internal.session.room.version.DefaultRoomVersionService
 import org.matrix.android.sdk.internal.session.search.SearchTask
 import javax.inject.Inject
 
@@ -61,6 +62,7 @@ internal class DefaultRoomFactory @Inject constructor(private val cryptoService:
                                                       private val relationServiceFactory: DefaultRelationService.Factory,
                                                       private val membershipServiceFactory: DefaultMembershipService.Factory,
                                                       private val roomPushRuleServiceFactory: DefaultRoomPushRuleService.Factory,
+                                                      private val roomVersionServiceFactory: DefaultRoomVersionService.Factory,
                                                       private val roomAccountDataServiceFactory: DefaultRoomAccountDataService.Factory,
                                                       private val sendStateTask: SendStateTask,
                                                       private val viaParameterFinder: ViaParameterFinder,
@@ -89,7 +91,8 @@ internal class DefaultRoomFactory @Inject constructor(private val cryptoService:
                 roomAccountDataService = roomAccountDataServiceFactory.create(roomId),
                 sendStateTask = sendStateTask,
                 searchTask = searchTask,
-                viaParameterFinder = viaParameterFinder
+                viaParameterFinder = viaParameterFinder,
+                roomVersionService = roomVersionServiceFactory.create(roomId)
         )
     }
 }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/RoomModule.kt

@@ -92,6 +92,8 @@ import org.matrix.android.sdk.internal.session.room.typing.DefaultSendTypingTask
 import org.matrix.android.sdk.internal.session.room.typing.SendTypingTask
 import org.matrix.android.sdk.internal.session.room.uploads.DefaultGetUploadsTask
 import org.matrix.android.sdk.internal.session.room.uploads.GetUploadsTask
+import org.matrix.android.sdk.internal.session.room.version.DefaultRoomVersionUpgradeTask
+import org.matrix.android.sdk.internal.session.room.version.RoomVersionUpgradeTask
 import org.matrix.android.sdk.internal.session.space.DefaultSpaceService
 import retrofit2.Retrofit
 
@@ -243,4 +245,7 @@ internal abstract class RoomModule {
 
     @Binds
     abstract fun bindGetEventTask(task: DefaultGetEventTask): GetEventTask
+
+    @Binds
+    abstract fun bindRoomVersionUpgradeTask(task: DefaultRoomVersionUpgradeTask): RoomVersionUpgradeTask
 }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/RoomUpgradeBody.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.internal.session.room
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+@JsonClass(generateAdapter = true)
+internal data class RoomUpgradeBody(
+        @Json(name = "new_version")
+        val newVersion: String
+)

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/RoomUpgradeResponse.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.internal.session.room
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+@JsonClass(generateAdapter = true)
+internal data class RoomUpgradeResponse(
+        @Json(name = "replacement_room")
+        val replacementRoomId: String
+)

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/summary/RoomSummaryUpdater.kt

@@ -354,7 +354,7 @@ internal class RoomSummaryUpdater @Inject constructor(
                             // we keep real m.child/m.parent relations and add the one for common memberships
                             dmRoom.flattenParentIds += "|${flattenRelated.joinToString("|")}|"
                         }
-//                        Timber.v("## SPACES: flatten of ${dmRoom.otherMemberIds.joinToString(",")} is ${dmRoom.flattenParentIds}")
+                        Timber.v("## SPACES: flatten of ${dmRoom.otherMemberIds.joinToString(",")} is ${dmRoom.flattenParentIds}")
                     }
 
             // Maybe a good place to count the number of notifications for spaces?

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/version/DefaultRoomVersionService.kt

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.internal.session.room.version
+
+import com.zhuinden.monarchy.Monarchy
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+import io.realm.Realm
+import org.matrix.android.sdk.api.query.QueryStringValue
+import org.matrix.android.sdk.api.session.events.model.EventType
+import org.matrix.android.sdk.api.session.events.model.toModel
+import org.matrix.android.sdk.api.session.room.model.PowerLevelsContent
+import org.matrix.android.sdk.api.session.room.model.create.RoomCreateContent
+import org.matrix.android.sdk.api.session.room.powerlevels.PowerLevelsHelper
+import org.matrix.android.sdk.api.session.room.version.RoomVersionService
+import org.matrix.android.sdk.internal.database.mapper.HomeServerCapabilitiesMapper
+import org.matrix.android.sdk.internal.database.model.HomeServerCapabilitiesEntity
+import org.matrix.android.sdk.internal.database.query.get
+import org.matrix.android.sdk.internal.di.SessionDatabase
+import org.matrix.android.sdk.internal.session.room.state.StateEventDataSource
+
+internal class DefaultRoomVersionService @AssistedInject constructor(
+        @Assisted private val roomId: String,
+        @SessionDatabase private val monarchy: Monarchy,
+        private val stateEventDataSource: StateEventDataSource,
+        private val roomVersionUpgradeTask: RoomVersionUpgradeTask
+) : RoomVersionService {
+
+    @AssistedFactory
+    interface Factory {
+        fun create(roomId: String): DefaultRoomVersionService
+    }
+
+    override fun getRoomVersion(): String {
+        return stateEventDataSource.getStateEvent(roomId, EventType.STATE_ROOM_CREATE, QueryStringValue.IsEmpty)
+                ?.content
+                ?.toModel<RoomCreateContent>()
+                ?.roomVersion
+        // as per spec -> Defaults to "1" if the key does not exist.
+                ?: DEFAULT_ROOM_VERSION
+    }
+
+    override suspend fun upgradeToVersion(version: String): String {
+        return roomVersionUpgradeTask.execute(
+                RoomVersionUpgradeTask.Params(
+                        roomId, version
+                )
+        )
+    }
+
+    override suspend fun getRecommendedVersion(): String {
+        return Realm.getInstance(monarchy.realmConfiguration).use { realm ->
+            HomeServerCapabilitiesEntity.get(realm)?.let {
+                HomeServerCapabilitiesMapper.map(it)
+            }?.roomVersions?.defaultRoomVersion ?: DEFAULT_ROOM_VERSION
+        }
+    }
+
+    override fun userMayUpgradeRoom(userId: String): Boolean {
+        val powerLevelsHelper = stateEventDataSource.getStateEvent(roomId, EventType.STATE_ROOM_POWER_LEVELS, QueryStringValue.NoCondition)
+                ?.content?.toModel<PowerLevelsContent>()
+                ?.let { PowerLevelsHelper(it) }
+
+        return powerLevelsHelper?.isUserAllowedToSend(userId, true, EventType.STATE_ROOM_TOMBSTONE) ?: false
+    }
+
+    companion object {
+        const val DEFAULT_ROOM_VERSION = "1"
+    }
+}

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/version/RoomVersionUpgradeTask.kt

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.internal.session.room.version
+
+import io.realm.RealmConfiguration
+import org.matrix.android.sdk.api.extensions.tryOrNull
+import org.matrix.android.sdk.api.session.room.model.Membership
+import org.matrix.android.sdk.internal.database.awaitNotEmptyResult
+import org.matrix.android.sdk.internal.database.model.RoomSummaryEntity
+import org.matrix.android.sdk.internal.database.model.RoomSummaryEntityFields
+import org.matrix.android.sdk.internal.di.SessionDatabase
+import org.matrix.android.sdk.internal.network.GlobalErrorReceiver
+import org.matrix.android.sdk.internal.network.executeRequest
+import org.matrix.android.sdk.internal.session.room.RoomAPI
+import org.matrix.android.sdk.internal.session.room.RoomUpgradeBody
+import org.matrix.android.sdk.internal.task.Task
+import java.util.concurrent.TimeUnit
+import javax.inject.Inject
+
+internal interface RoomVersionUpgradeTask : Task<RoomVersionUpgradeTask.Params, String> {
+    data class Params(
+            val roomId: String,
+            val newVersion: String
+    )
+}
+
+internal class DefaultRoomVersionUpgradeTask @Inject constructor(
+        private val roomAPI: RoomAPI,
+        private val globalErrorReceiver: GlobalErrorReceiver,
+        @SessionDatabase
+        private val realmConfiguration: RealmConfiguration
+) : RoomVersionUpgradeTask {
+
+    override suspend fun execute(params: RoomVersionUpgradeTask.Params): String {
+        val replacementRoomId = executeRequest(globalErrorReceiver) {
+            roomAPI.upgradeRoom(
+                    roomId = params.roomId,
+                    body = RoomUpgradeBody(params.newVersion)
+            )
+        }.replacementRoomId
+
+        // Wait for room to come back from the sync (but it can maybe be in the DB if the sync response is received before)
+        tryOrNull {
+            awaitNotEmptyResult(realmConfiguration, TimeUnit.MINUTES.toMillis(1L)) { realm ->
+                realm.where(RoomSummaryEntity::class.java)
+                        .equalTo(RoomSummaryEntityFields.ROOM_ID, replacementRoomId)
+                        .equalTo(RoomSummaryEntityFields.MEMBERSHIP_STR, Membership.JOIN.name)
+            }
+        }
+        return replacementRoomId
+    }
+}

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/space/DefaultSpace.kt

@@ -86,6 +86,12 @@ internal class DefaultSpace(
         )
     }
 
+    override fun getChildInfo(roomId: String): SpaceChildContent? {
+        return room.getStateEvents(setOf(EventType.STATE_SPACE_CHILD), QueryStringValue.Equals(roomId))
+                .firstOrNull()
+                ?.content.toModel<SpaceChildContent>()
+    }
+
     override suspend fun setChildrenOrder(roomId: String, order: String?) {
         val existing = room.getStateEvents(setOf(EventType.STATE_SPACE_CHILD), QueryStringValue.Equals(roomId))
                 .firstOrNull()

vector/src/main/java/im/vector/app/VectorApplication.kt

@@ -159,7 +159,6 @@ class VectorApplication :
             // Do not display the name change popup
             doNotShowDisclaimerDialog(this)
         }
-
         if (authenticationService.hasAuthenticatedSessions() && !activeSessionHolder.hasActiveSession()) {
             val lastAuthenticatedSession = authenticationService.getLastAuthenticatedSession()!!
             activeSessionHolder.setActiveSession(lastAuthenticatedSession)

vector/src/main/java/im/vector/app/core/di/ScreenComponent.kt

@@ -40,12 +40,14 @@ import im.vector.app.features.debug.DebugMenuActivity
 import im.vector.app.features.devtools.RoomDevToolActivity
 import im.vector.app.features.home.HomeActivity
 import im.vector.app.features.home.HomeModule
+import im.vector.app.features.home.room.detail.JoinReplacementRoomBottomSheet
 import im.vector.app.features.home.room.detail.RoomDetailActivity
 import im.vector.app.features.home.room.detail.readreceipts.DisplayReadReceiptsBottomSheet
 import im.vector.app.features.home.room.detail.search.SearchActivity
 import im.vector.app.features.home.room.detail.timeline.action.MessageActionsBottomSheet
 import im.vector.app.features.home.room.detail.timeline.edithistory.ViewEditHistoryBottomSheet
 import im.vector.app.features.home.room.detail.timeline.reactions.ViewReactionsBottomSheet
+import im.vector.app.features.home.room.detail.upgrade.MigrateRoomBottomSheet
 import im.vector.app.features.home.room.detail.widget.RoomWidgetsBottomSheet
 import im.vector.app.features.home.room.filtered.FilteredRoomsActivity
 import im.vector.app.features.home.room.list.RoomListModule
@@ -191,6 +193,8 @@ interface ScreenComponent {
     fun inject(bottomSheet: SpaceSettingsMenuBottomSheet)
     fun inject(bottomSheet: InviteRoomSpaceChooserBottomSheet)
     fun inject(bottomSheet: SpaceInviteBottomSheet)
+    fun inject(bottomSheet: JoinReplacementRoomBottomSheet)
+    fun inject(bottomSheet: MigrateRoomBottomSheet)
 
     /* ==========================================================================================
      * Others

vector/src/main/java/im/vector/app/core/platform/VectorBaseBottomSheetDialogFragment.kt

@@ -46,7 +46,7 @@ import java.util.concurrent.TimeUnit
 /**
  * Add MvRx capabilities to bottomsheetdialog (like BaseMvRxFragment)
  */
-abstract class VectorBaseBottomSheetDialogFragment<VB: ViewBinding> : BottomSheetDialogFragment(), MvRxView {
+abstract class VectorBaseBottomSheetDialogFragment<VB : ViewBinding> : BottomSheetDialogFragment(), MvRxView {
 
     private val mvrxViewIdProperty = MvRxViewId()
     final override val mvrxViewId: String by mvrxViewIdProperty
@@ -168,6 +168,10 @@ abstract class VectorBaseBottomSheetDialogFragment<VB: ViewBinding> : BottomShee
 
     @CallSuper
     override fun invalidate() {
+        forceExpandState()
+    }
+
+    protected fun forceExpandState() {
         if (showExpanded) {
             // Force the bottom sheet to be expanded
             bottomSheetBehavior?.state = BottomSheetBehavior.STATE_EXPANDED

vector/src/main/java/im/vector/app/core/ui/list/GenericProgressBarItem.kt

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package im.vector.app.core.ui.list
+
+import android.widget.ProgressBar
+import com.airbnb.epoxy.EpoxyAttribute
+import com.airbnb.epoxy.EpoxyModelClass
+import im.vector.app.R
+import im.vector.app.core.epoxy.VectorEpoxyHolder
+import im.vector.app.core.epoxy.VectorEpoxyModel
+
+/**
+ * A generic list item.
+ * Displays an item with a title, and optional description.
+ * Can display an accessory on the right, that can be an image or an indeterminate progress.
+ * If provided with an action, will display a button at the bottom of the list item.
+ */
+@EpoxyModelClass(layout = R.layout.item_generic_progress)
+abstract class GenericProgressBarItem : VectorEpoxyModel<GenericProgressBarItem.Holder>() {
+
+    @EpoxyAttribute
+    var progress: Int = 0
+
+    @EpoxyAttribute
+    var total: Int = 100
+
+    @EpoxyAttribute
+    var indeterminate: Boolean = false
+
+    override fun bind(holder: Holder) {
+        super.bind(holder)
+        holder.progressbar.progress = progress
+        holder.progressbar.max = total
+        holder.progressbar.isIndeterminate = indeterminate
+    }
+
+    class Holder : VectorEpoxyHolder() {
+        val progressbar by bind<ProgressBar>(R.id.genericProgressBar)
+    }
+}

vector/src/main/java/im/vector/app/core/ui/views/NotificationAreaView.kt

@@ -21,7 +21,7 @@ import android.graphics.Color
 import android.text.method.LinkMovementMethod
 import android.util.AttributeSet
 import android.view.View
-import android.widget.RelativeLayout
+import android.widget.LinearLayout
 import androidx.core.content.ContextCompat
 import androidx.core.text.italic
 import im.vector.app.R
@@ -44,7 +44,7 @@ class NotificationAreaView @JvmOverloads constructor(
         context: Context,
         attrs: AttributeSet? = null,
         defStyleAttr: Int = 0
-) : RelativeLayout(context, attrs, defStyleAttr) {
+) : LinearLayout(context, attrs, defStyleAttr) {
 
     var delegate: Delegate? = null
     private var state: State = State.Initial
@@ -127,7 +127,7 @@ class NotificationAreaView @JvmOverloads constructor(
 
     private fun renderTombstone(state: State.Tombstone) {
         visibility = View.VISIBLE
-        views.roomNotificationIcon.setImageResource(R.drawable.error)
+        views.roomNotificationIcon.setImageResource(R.drawable.ic_warning_badge)
         val message = span {
             +resources.getString(R.string.room_tombstone_versioned_description)
             +"\n"

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

@@ -50,7 +50,8 @@ enum class Command(val command: String, val parameters: String, @StringRes val d
     CREATE_SPACE("/createspace", "<name> <invitee>*", R.string.command_description_create_space,  true),
     ADD_TO_SPACE("/addToSpace", "spaceId", R.string.command_description_create_space, true),
     JOIN_SPACE("/joinSpace", "spaceId", R.string.command_description_join_space, true),
-    LEAVE_ROOM("/leave", "<roomId?>", R.string.command_description_leave_room, true);
+    LEAVE_ROOM("/leave", "<roomId?>", R.string.command_description_leave_room, true),
+    UPGRADE_ROOM("/upgraderoom", "newVersion", R.string.command_description_upgrade_room, true);
 
     val length
         get() = command.length + 1

vector/src/main/java/im/vector/app/features/command/CommandParser.kt

@@ -330,6 +330,10 @@ object CommandParser {
                             spaceIdOrAlias
                     )
                 }
+                Command.UPGRADE_ROOM.command           -> {
+                    val newVersion = textMessage.substring(Command.UPGRADE_ROOM.command.length).trim()
+                    ParsedCommand.UpgradeRoom(newVersion)
+                }
                 else                                   -> {
                     // Unknown command
                     ParsedCommand.ErrorUnknownSlashCommand(slashCommand)

vector/src/main/java/im/vector/app/features/command/ParsedCommand.kt

@@ -61,4 +61,5 @@ sealed class ParsedCommand {
     class AddToSpace(val spaceId: String) : ParsedCommand()
     class JoinSpace(val spaceIdOrAlias: String) : ParsedCommand()
     class LeaveRoom(val roomId: String) : ParsedCommand()
+    class UpgradeRoom(val newVersion: String) : ParsedCommand()
 }

vector/src/main/java/im/vector/app/features/home/room/detail/JoinReplacementRoomBottomSheet.kt

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import com.airbnb.mvrx.Fail
+import com.airbnb.mvrx.Loading
+import com.airbnb.mvrx.Success
+import com.airbnb.mvrx.Uninitialized
+import com.airbnb.mvrx.parentFragmentViewModel
+import com.airbnb.mvrx.withState
+import im.vector.app.R
+import im.vector.app.core.di.ScreenComponent
+import im.vector.app.core.epoxy.ClickListener
+import im.vector.app.core.error.ErrorFormatter
+import im.vector.app.core.platform.ButtonStateView
+import im.vector.app.core.platform.VectorBaseBottomSheetDialogFragment
+import im.vector.app.databinding.BottomSheetTombstoneJoinBinding
+import javax.inject.Inject
+
+class JoinReplacementRoomBottomSheet :
+        VectorBaseBottomSheetDialogFragment<BottomSheetTombstoneJoinBinding>() {
+
+    override fun getBinding(inflater: LayoutInflater, container: ViewGroup?) =
+            BottomSheetTombstoneJoinBinding.inflate(inflater, container, false)
+
+    @Inject
+    lateinit var errorFormatter: ErrorFormatter
+
+    override fun injectWith(injector: ScreenComponent) {
+        injector.inject(this)
+    }
+
+    private val viewModel: RoomDetailViewModel by parentFragmentViewModel()
+
+    override val showExpanded: Boolean
+        get() = true
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+
+        views.roomUpgradeButton.retryClicked = object : ClickListener {
+            override fun invoke(view: View) {
+                withState(viewModel) { it.tombstoneEvent }?.let {
+                    viewModel.handle(RoomDetailAction.HandleTombstoneEvent(it))
+                }
+            }
+        }
+
+        viewModel.selectSubscribe(this, RoomDetailViewState::tombstoneEventHandling) { joinState ->
+            when (joinState) {
+                // it should never be Uninitialized
+                Uninitialized -> views.roomUpgradeButton.render(ButtonStateView.State.Loaded)
+                is Loading    -> {
+                    views.roomUpgradeButton.render(ButtonStateView.State.Loading)
+                    views.descriptionText.setText(R.string.it_may_take_some_time)
+                }
+                is Success    -> {
+                    views.roomUpgradeButton.render(ButtonStateView.State.Loaded)
+                    dismiss()
+                }
+                is Fail       -> {
+                    // display the error message
+                    views.descriptionText.text = errorFormatter.toHumanReadable(joinState.error)
+                    views.roomUpgradeButton.render(ButtonStateView.State.Error)
+                }
+            }
+        }
+    }
+}

vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailAction.kt

@@ -108,4 +108,5 @@ sealed class RoomDetailAction : VectorViewModelAction {
 
     // Failed messages
     object RemoveAllFailedMessages : RoomDetailAction()
+    data class RoomUpgradeSuccess(val replacementRoom: String): RoomDetailAction()
 }

vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailFragment.kt

@@ -51,6 +51,7 @@ import androidx.core.view.ViewCompat
 import androidx.core.view.forEach
 import androidx.core.view.isInvisible
 import androidx.core.view.isVisible
+import androidx.fragment.app.setFragmentResultListener
 import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.ItemTouchHelper
 import androidx.recyclerview.widget.LinearLayoutManager
@@ -147,6 +148,7 @@ import im.vector.app.features.home.room.detail.timeline.item.MessageTextItem
 import im.vector.app.features.home.room.detail.timeline.item.ReadReceiptData
 import im.vector.app.features.home.room.detail.timeline.reactions.ViewReactionsBottomSheet
 import im.vector.app.features.home.room.detail.timeline.url.PreviewUrlRetriever
+import im.vector.app.features.home.room.detail.upgrade.MigrateRoomBottomSheet
 import im.vector.app.features.home.room.detail.widget.RoomWidgetsBottomSheet
 import im.vector.app.features.html.EventHtmlRenderer
 import im.vector.app.features.html.PillImageSpan
@@ -306,6 +308,15 @@ class RoomDetailFragment @Inject constructor(
 
     private lateinit var emojiPopup: EmojiPopup
 
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setFragmentResultListener(MigrateRoomBottomSheet.REQUEST_KEY) { _, bundle ->
+            bundle.getString(MigrateRoomBottomSheet.BUNDLE_KEY_REPLACEMENT_ROOM)?.let { replacementRoomId ->
+                roomDetailViewModel.handle(RoomDetailAction.RoomUpgradeSuccess(replacementRoomId))
+            }
+        }
+    }
+
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
         sharedActionViewModel = activityViewModelProvider.get(MessageSharedActionViewModel::class.java)
@@ -405,6 +416,8 @@ class RoomDetailFragment @Inject constructor(
                 is RoomDetailViewEvents.StartChatEffect                  -> handleChatEffect(it.type)
                 RoomDetailViewEvents.StopChatEffects                     -> handleStopChatEffects()
                 is RoomDetailViewEvents.DisplayAndAcceptCall             -> acceptIncomingCall(it)
+                RoomDetailViewEvents.RoomReplacementStarted              -> handleRoomReplacement()
+                is RoomDetailViewEvents.ShowRoomUpgradeDialog            -> handleShowRoomUpgradeDialog(it)
             }.exhaustive
         }
 
@@ -423,6 +436,19 @@ class RoomDetailFragment @Inject constructor(
         startActivity(intent)
     }
 
+    private fun handleRoomReplacement() {
+        // this will join a new room, it can take time and might fail
+        // so we need to report progress and retry
+        val tag = JoinReplacementRoomBottomSheet::javaClass.name
+        JoinReplacementRoomBottomSheet().show(childFragmentManager, tag)
+    }
+
+    private fun handleShowRoomUpgradeDialog(roomDetailViewEvents: RoomDetailViewEvents.ShowRoomUpgradeDialog) {
+        val tag = MigrateRoomBottomSheet::javaClass.name
+        MigrateRoomBottomSheet.newInstance(roomDetailArgs.roomId, roomDetailViewEvents.newVersion)
+                .show(parentFragmentManager, tag)
+    }
+
     private fun handleChatEffect(chatEffect: ChatEffect) {
         when (chatEffect) {
             ChatEffect.CONFETTI -> {
@@ -1306,16 +1332,14 @@ class RoomDetailFragment @Inject constructor(
     private fun renderTombstoneEventHandling(async: Async<String>) {
         when (async) {
             is Loading -> {
-                // TODO Better handling progress
+                // shown in bottom sheet
-                vectorBaseActivity.showWaitingView(getString(R.string.joining_room))
             }
             is Success -> {
                 navigator.openRoom(vectorBaseActivity, async())
                 vectorBaseActivity.finish()
             }
             is Fail    -> {
-                vectorBaseActivity.hideWaitingView()
+                // shown in bottom sheet
-                vectorBaseActivity.toast(errorFormatter.toHumanReadable(async.error))
             }
         }
     }

vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailViewEvents.kt

@@ -94,4 +94,6 @@ sealed class RoomDetailViewEvents : VectorViewEvents {
 
     data class StartChatEffect(val type: ChatEffect) : RoomDetailViewEvents()
     object StopChatEffects : RoomDetailViewEvents()
+    object RoomReplacementStarted : RoomDetailViewEvents()
+    data class ShowRoomUpgradeDialog(val newVersion: String, val isPublic: Boolean): RoomDetailViewEvents()
 }

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

@@ -321,6 +321,11 @@ class RoomDetailViewModel @AssistedInject constructor(
             is RoomDetailAction.DoNotShowPreviewUrlFor           -> handleDoNotShowPreviewUrlFor(action)
             RoomDetailAction.RemoveAllFailedMessages             -> handleRemoveAllFailedMessages()
             RoomDetailAction.ResendAll                           -> handleResendAll()
+            is RoomDetailAction.RoomUpgradeSuccess               -> {
+                setState {
+                    copy(tombstoneEventHandling = Success(action.replacementRoom))
+                }
+            }
         }.exhaustive
     }
 
@@ -585,6 +590,11 @@ class RoomDetailViewModel @AssistedInject constructor(
             val viaServers = MatrixPatterns.extractServerNameFromId(action.event.senderId)
                     ?.let { listOf(it) }
                     .orEmpty()
+            // need to provide feedback as joining could take some time
+            _viewEvents.post(RoomDetailViewEvents.RoomReplacementStarted)
+            setState {
+                copy(tombstoneEventHandling = Loading())
+            }
             viewModelScope.launch {
                 val result = runCatchingToAsync {
                     session.joinRoom(roomId, viaServers = viaServers)
@@ -817,6 +827,23 @@ class RoomDetailViewModel @AssistedInject constructor(
                             _viewEvents.post(RoomDetailViewEvents.SlashCommandHandled())
                             popDraft()
                         }
+                        is ParsedCommand.UpgradeRoom              -> {
+                            _viewEvents.post(
+                                    RoomDetailViewEvents.ShowRoomUpgradeDialog(
+                                            slashCommandResult.newVersion,
+                                            room.roomSummary()?.isPublic ?: false
+                                    )
+                            )
+//                            session.coroutineScope.launch {
+//                                try {
+//                                    room.upgradeToVersion(slashCommandResult.newVersion)
+//                                } catch (failure: Throwable) {
+//                                    _viewEvents.post(RoomDetailViewEvents.SlashCommandResultError(failure))
+//                                }
+//                            }
+                            _viewEvents.post(RoomDetailViewEvents.SlashCommandHandled())
+                            popDraft()
+                        }
                     }.exhaustive
                 }
                 is SendMode.EDIT    -> {

vector/src/main/java/im/vector/app/features/home/room/detail/upgrade/MigrateRoomAction.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail.upgrade
+
+import im.vector.app.core.platform.VectorViewModelAction
+
+sealed class MigrateRoomAction : VectorViewModelAction {
+    data class SetAutoInvite(val autoInvite: Boolean) : MigrateRoomAction()
+    data class SetUpdateKnownParentSpace(val update: Boolean) : MigrateRoomAction()
+    object UpgradeRoom : MigrateRoomAction()
+}

vector/src/main/java/im/vector/app/features/home/room/detail/upgrade/MigrateRoomBottomSheet.kt

@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail.upgrade
+
+import android.os.Bundle
+import android.os.Parcelable
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.setFragmentResult
+import com.airbnb.epoxy.OnModelBuildFinishedListener
+import com.airbnb.mvrx.Success
+import com.airbnb.mvrx.fragmentViewModel
+import com.airbnb.mvrx.withState
+import im.vector.app.core.di.ScreenComponent
+import im.vector.app.core.extensions.cleanup
+import im.vector.app.core.extensions.configureWith
+import im.vector.app.core.platform.VectorBaseBottomSheetDialogFragment
+import im.vector.app.databinding.BottomSheetGenericListBinding
+import kotlinx.parcelize.Parcelize
+import javax.inject.Inject
+
+class MigrateRoomBottomSheet :
+        VectorBaseBottomSheetDialogFragment<BottomSheetGenericListBinding>(),
+        MigrateRoomViewModel.Factory, MigrateRoomController.InteractionListener {
+
+    @Parcelize
+    data class Args(
+            val roomId: String,
+            val newVersion: String
+    ) : Parcelable
+
+    @Inject
+    lateinit var viewModelFactory: MigrateRoomViewModel.Factory
+
+    override val showExpanded = true
+
+    @Inject
+    lateinit var epoxyController: MigrateRoomController
+
+    val viewModel: MigrateRoomViewModel by fragmentViewModel()
+
+    override fun injectWith(injector: ScreenComponent) {
+        injector.inject(this)
+    }
+
+    override fun getBinding(inflater: LayoutInflater, container: ViewGroup?) =
+            BottomSheetGenericListBinding.inflate(inflater, container, false)
+
+    override fun invalidate() = withState(viewModel) { state ->
+        epoxyController.setData(state)
+        super.invalidate()
+
+        when (val result = state.upgradingStatus) {
+            is Success -> {
+                val result = result.invoke()
+                if (result is UpgradeRoomViewModelTask.Result.Success) {
+                    setFragmentResult(REQUEST_KEY, Bundle().apply {
+                        putString(BUNDLE_KEY_REPLACEMENT_ROOM, result.replacementRoomId)
+                    })
+                    dismiss()
+                }
+            }
+        }
+    }
+
+    val postBuild = OnModelBuildFinishedListener {
+        view?.post { forceExpandState() }
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        epoxyController.callback = this
+        views.bottomSheetRecyclerView.configureWith(epoxyController)
+        epoxyController.addModelBuildListener(postBuild)
+    }
+
+    override fun onDestroyView() {
+        views.bottomSheetRecyclerView.cleanup()
+        epoxyController.removeModelBuildListener(postBuild)
+        super.onDestroyView()
+    }
+
+    override fun create(initialState: MigrateRoomViewState): MigrateRoomViewModel {
+        return viewModelFactory.create(initialState)
+    }
+
+    companion object {
+
+        const val REQUEST_KEY = "MigrateRoomBottomSheetRequest"
+        const val BUNDLE_KEY_REPLACEMENT_ROOM = "BUNDLE_KEY_REPLACEMENT_ROOM"
+
+        fun newInstance(roomId: String, newVersion: String)
+                : MigrateRoomBottomSheet {
+            return MigrateRoomBottomSheet().apply {
+                setArguments(Args(roomId, newVersion))
+            }
+        }
+    }
+
+    override fun onAutoInvite(autoInvite: Boolean) {
+        viewModel.handle(MigrateRoomAction.SetAutoInvite(autoInvite))
+    }
+
+    override fun onAutoUpdateParent(update: Boolean) {
+        viewModel.handle(MigrateRoomAction.SetUpdateKnownParentSpace(update))
+    }
+
+    override fun onConfirmUpgrade() {
+        viewModel.handle(MigrateRoomAction.UpgradeRoom)
+    }
+}

vector/src/main/java/im/vector/app/features/home/room/detail/upgrade/MigrateRoomController.kt

@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail.upgrade
+
+import com.airbnb.epoxy.TypedEpoxyController
+import com.airbnb.mvrx.Loading
+import com.airbnb.mvrx.Success
+import im.vector.app.R
+import im.vector.app.core.epoxy.errorWithRetryItem
+import im.vector.app.core.error.ErrorFormatter
+import im.vector.app.core.resources.StringProvider
+import im.vector.app.core.ui.bottomsheet.bottomSheetTitleItem
+import im.vector.app.core.ui.list.ItemStyle
+import im.vector.app.core.ui.list.genericFooterItem
+import im.vector.app.core.ui.list.genericProgressBarItem
+import im.vector.app.features.form.formSubmitButtonItem
+import im.vector.app.features.form.formSwitchItem
+import javax.inject.Inject
+
+class MigrateRoomController @Inject constructor(
+        private val stringProvider: StringProvider,
+        private val errorFormatter: ErrorFormatter
+) : TypedEpoxyController<MigrateRoomViewState>() {
+
+    interface InteractionListener {
+        fun onAutoInvite(autoInvite: Boolean)
+        fun onAutoUpdateParent(update: Boolean)
+        fun onConfirmUpgrade()
+    }
+
+    var callback: InteractionListener? = null
+
+    override fun buildModels(data: MigrateRoomViewState?) {
+        data ?: return
+
+        val host = this@MigrateRoomController
+
+        bottomSheetTitleItem {
+            id("title")
+            title(
+                    host.stringProvider.getString(if (data.isPublic) R.string.upgrade_public_room else R.string.upgrade_private_room)
+            )
+        }
+
+        genericFooterItem {
+            id("warning_text")
+            centered(false)
+            style(ItemStyle.NORMAL_TEXT)
+            text(host.stringProvider.getString(R.string.upgrade_room_warning))
+        }
+
+        genericFooterItem {
+            id("from_to_room")
+            centered(false)
+            style(ItemStyle.NORMAL_TEXT)
+            text(host.stringProvider.getString(R.string.upgrade_public_room_from_to, data.currentVersion, data.newVersion))
+        }
+
+        if (!data.isPublic && data.otherMemberCount > 0) {
+            formSwitchItem {
+                id("auto_invite")
+                switchChecked(data.shouldIssueInvites)
+                title(host.stringProvider.getString(R.string.upgrade_room_auto_invite))
+                listener { switch -> host.callback?.onAutoInvite(switch) }
+            }
+        }
+
+        if (data.knownParents.isNotEmpty()) {
+            formSwitchItem {
+                id("update_parent")
+                switchChecked(data.shouldUpdateKnownParents)
+                title(host.stringProvider.getString(R.string.upgrade_room_update_parent))
+                listener { switch -> host.callback?.onAutoUpdateParent(switch) }
+            }
+        }
+        when (data.upgradingStatus) {
+            is Loading -> {
+                genericProgressBarItem {
+                    id("upgrade_progress")
+                    indeterminate(data.upgradingProgressIndeterminate)
+                    progress(data.upgradingProgress)
+                    total(data.upgradingProgressTotal)
+                }
+            }
+            is Success -> {
+                when (val result = data.upgradingStatus.invoke()) {
+                    is UpgradeRoomViewModelTask.Result.Failure -> {
+                        val errorText = when (result) {
+                            is UpgradeRoomViewModelTask.Result.UnknownRoom  -> {
+                                // should not happen
+                                host.stringProvider.getString(R.string.unknown_error)
+                            }
+                            is UpgradeRoomViewModelTask.Result.NotAllowed   -> {
+                                host.stringProvider.getString(R.string.upgrade_room_no_power_to_manage)
+                            }
+                            is UpgradeRoomViewModelTask.Result.ErrorFailure -> {
+                                host.errorFormatter.toHumanReadable(result.throwable)
+                            }
+                            else                                            -> null
+                        }
+                        errorWithRetryItem {
+                            id("error")
+                            text(errorText)
+                            listener { host.callback?.onConfirmUpgrade() }
+                        }
+                    }
+                    is UpgradeRoomViewModelTask.Result.Success -> {
+                        // nop, dismisses
+                    }
+                }
+            }
+            else       -> {
+                formSubmitButtonItem {
+                    id("migrate")
+                    buttonTitleId(R.string.upgrade)
+                    buttonClickListener { host.callback?.onConfirmUpgrade() }
+                }
+            }
+        }
+    }
+}

vector/src/main/java/im/vector/app/features/home/room/detail/upgrade/MigrateRoomViewModel.kt

@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail.upgrade
+
+import com.airbnb.mvrx.ActivityViewModelContext
+import com.airbnb.mvrx.FragmentViewModelContext
+import com.airbnb.mvrx.Loading
+import com.airbnb.mvrx.MvRxViewModelFactory
+import com.airbnb.mvrx.Success
+import com.airbnb.mvrx.ViewModelContext
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+import im.vector.app.core.platform.EmptyViewEvents
+import im.vector.app.core.platform.VectorViewModel
+import im.vector.app.features.session.coroutineScope
+import kotlinx.coroutines.launch
+import org.matrix.android.sdk.api.session.Session
+
+class MigrateRoomViewModel @AssistedInject constructor(
+        @Assisted initialState: MigrateRoomViewState,
+        private val session: Session,
+        private val upgradeRoomViewModelTask: UpgradeRoomViewModelTask)
+    : VectorViewModel<MigrateRoomViewState, MigrateRoomAction, EmptyViewEvents>(initialState) {
+
+    init {
+        val room = session.getRoom(initialState.roomId)
+        val summary = session.getRoomSummary(initialState.roomId)
+        setState {
+            copy(
+                    currentVersion = room?.getRoomVersion(),
+                    isPublic = summary?.isPublic ?: false,
+                    otherMemberCount = summary?.otherMemberIds?.count() ?: 0,
+                    knownParents = summary?.flattenParentIds ?: emptyList()
+            )
+        }
+    }
+
+    @AssistedFactory
+    interface Factory {
+        fun create(initialState: MigrateRoomViewState): MigrateRoomViewModel
+    }
+
+    companion object : MvRxViewModelFactory<MigrateRoomViewModel, MigrateRoomViewState> {
+
+        override fun create(viewModelContext: ViewModelContext, state: MigrateRoomViewState): MigrateRoomViewModel? {
+            val factory = when (viewModelContext) {
+                is FragmentViewModelContext -> viewModelContext.fragment as? Factory
+                is ActivityViewModelContext -> viewModelContext.activity as? Factory
+            }
+            return factory?.create(state) ?: error("You should let your activity/fragment implements Factory interface")
+        }
+    }
+
+    override fun handle(action: MigrateRoomAction) {
+        when (action) {
+            is MigrateRoomAction.SetAutoInvite             -> {
+                setState {
+                    copy(shouldIssueInvites = action.autoInvite)
+                }
+            }
+            is MigrateRoomAction.SetUpdateKnownParentSpace -> {
+                setState {
+                    copy(shouldUpdateKnownParents = action.update)
+                }
+            }
+            MigrateRoomAction.UpgradeRoom                  -> {
+                handleUpgradeRoom(action)
+            }
+        }
+    }
+
+    val upgradingProgress: ((indeterminate: Boolean, progress: Int, total: Int) -> Unit) = { indeterminate, progress, total ->
+        setState {
+            copy(
+                    upgradingProgress = progress,
+                    upgradingProgressTotal = total,
+                    upgradingProgressIndeterminate = indeterminate
+            )
+        }
+    }
+
+    private fun handleUpgradeRoom(action: MigrateRoomAction) = withState { state ->
+        val summary = session.getRoomSummary(state.roomId)
+        setState {
+            copy(upgradingStatus = Loading())
+        }
+        session.coroutineScope.launch {
+            val result = upgradeRoomViewModelTask.execute(UpgradeRoomViewModelTask.Params(
+                    roomId = state.roomId,
+                    newVersion = state.newVersion,
+                    userIdsToAutoInvite = summary?.otherMemberIds?.takeIf { state.shouldIssueInvites } ?: emptyList(),
+                    parentSpaceToUpdate = summary?.flattenParentIds?.takeIf { state.shouldUpdateKnownParents } ?: emptyList(),
+                    progressReporter = upgradingProgress
+            ))
+
+            setState {
+                copy(upgradingStatus = Success(result))
+            }
+        }
+    }
+}

vector/src/main/java/im/vector/app/features/home/room/detail/upgrade/MigrateRoomViewState.kt

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail.upgrade
+
+import com.airbnb.mvrx.Async
+import com.airbnb.mvrx.MvRxState
+import com.airbnb.mvrx.Uninitialized
+
+data class MigrateRoomViewState(
+        val roomId: String,
+        val newVersion: String,
+        val currentVersion: String? = null,
+        val isPublic: Boolean = false,
+        val shouldIssueInvites: Boolean = false,
+        val shouldUpdateKnownParents: Boolean = false,
+        val otherMemberCount: Int = 0,
+        val knownParents: List<String> = emptyList(),
+        val upgradingStatus: Async<UpgradeRoomViewModelTask.Result> = Uninitialized,
+        val upgradingProgress: Int = 0,
+        val upgradingProgressTotal: Int = 0,
+        val upgradingProgressIndeterminate: Boolean = true
+) : MvRxState {
+    constructor(args: MigrateRoomBottomSheet.Args) : this(
+            roomId = args.roomId,
+            newVersion = args.newVersion
+    )
+}

vector/src/main/java/im/vector/app/features/home/room/detail/upgrade/UpgradeRoomViewModelTask.kt

@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.detail.upgrade
+
+import im.vector.app.core.platform.ViewModelTask
+import im.vector.app.core.resources.StringProvider
+import org.matrix.android.sdk.api.extensions.tryOrNull
+import org.matrix.android.sdk.api.session.Session
+import timber.log.Timber
+import javax.inject.Inject
+
+class UpgradeRoomViewModelTask @Inject constructor(
+        val session: Session,
+        val stringProvider: StringProvider
+) : ViewModelTask<UpgradeRoomViewModelTask.Params, UpgradeRoomViewModelTask.Result> {
+
+    sealed class Result {
+        data class Success(val replacementRoomId: String) : Result()
+        abstract class Failure(val throwable: Throwable?) : Result()
+        object UnknownRoom : Failure(null)
+        object NotAllowed : Failure(null)
+        class ErrorFailure(throwable: Throwable) : Failure(throwable)
+    }
+
+    data class Params(
+            val roomId: String,
+            val newVersion: String,
+            val userIdsToAutoInvite: List<String> = emptyList(),
+            val parentSpaceToUpdate: List<String> = emptyList(),
+            val progressReporter: ((indeterminate: Boolean, progress: Int, total: Int) -> Unit)? = null
+    )
+
+    override suspend fun execute(params: Params): Result {
+        params.progressReporter?.invoke(true, 0, 0)
+
+        val room = session.getRoom(params.roomId)
+                ?: return Result.UnknownRoom
+        if (!room.userMayUpgradeRoom(session.myUserId)) {
+            return Result.NotAllowed
+        }
+
+        val updatedRoomId = try {
+            room.upgradeToVersion(params.newVersion)
+        } catch (failure: Throwable) {
+            return Result.ErrorFailure(failure)
+        }
+
+        val totalStep = params.userIdsToAutoInvite.size + params.parentSpaceToUpdate.size
+        var currentStep = 0
+        params.userIdsToAutoInvite.forEach {
+            params.progressReporter?.invoke(false, currentStep, totalStep)
+            tryOrNull {
+                session.getRoom(updatedRoomId)?.invite(it)
+            }
+            currentStep++
+        }
+
+        params.parentSpaceToUpdate.forEach { parentId ->
+            params.progressReporter?.invoke(false, currentStep, totalStep)
+            // we try and silently fail
+            try {
+                session.getRoom(parentId)?.asSpace()?.let { parentSpace ->
+                    val currentInfo = parentSpace.getChildInfo(params.roomId)
+                    if (currentInfo != null) {
+                        parentSpace.addChildren(
+                                roomId = updatedRoomId,
+                                viaServers = currentInfo.via,
+                                order = currentInfo.order,
+                                autoJoin = currentInfo.autoJoin ?: false,
+                                suggested = currentInfo.suggested
+                        )
+
+                        parentSpace.removeChildren(params.roomId)
+                    }
+                }
+            } catch (failure: Throwable) {
+                Timber.d("## Migrate: Failed to update space parent. cause: ${failure.localizedMessage}")
+            } finally {
+                currentStep++
+            }
+        }
+
+        return Result.Success(updatedRoomId)
+    }
+}

vector/src/main/java/im/vector/app/features/settings/homeserver/HomeserverSettingsController.kt

@@ -26,16 +26,20 @@ import im.vector.app.core.epoxy.errorWithRetryItem
 import im.vector.app.core.epoxy.loadingItem
 import im.vector.app.core.error.ErrorFormatter
 import im.vector.app.core.resources.StringProvider
+import im.vector.app.core.ui.list.genericWithValueItem
 import im.vector.app.features.discovery.settingsCenteredImageItem
 import im.vector.app.features.discovery.settingsInfoItem
 import im.vector.app.features.discovery.settingsSectionTitleItem
+import im.vector.app.features.settings.VectorPreferences
 import org.matrix.android.sdk.api.federation.FederationVersion
 import org.matrix.android.sdk.api.session.homeserver.HomeServerCapabilities
+import org.matrix.android.sdk.api.session.homeserver.RoomVersionStatus
 import javax.inject.Inject
 
 class HomeserverSettingsController @Inject constructor(
         private val stringProvider: StringProvider,
-        private val errorFormatter: ErrorFormatter
+        private val errorFormatter: ErrorFormatter,
+        private val vectorPreferences: VectorPreferences
 ) : TypedEpoxyController<HomeServerSettingsViewState>() {
 
     var callback: Callback? = null
@@ -118,5 +122,36 @@ class HomeserverSettingsController @Inject constructor(
                 helperText(host.stringProvider.getString(R.string.settings_server_upload_size_content, "${limit / 1048576L} MB"))
             }
         }
+
+        if (vectorPreferences.developerMode()) {
+            val roomCapabilities = data.homeServerCapabilities.roomVersions
+            if (roomCapabilities != null) {
+                settingsSectionTitleItem {
+                    id("room_versions")
+                    titleResId(R.string.settings_server_room_versions)
+                }
+
+                genericWithValueItem {
+                    id("room_version_default")
+                    title(host.stringProvider.getString(R.string.settings_server_default_room_version))
+                    value(roomCapabilities.defaultRoomVersion)
+                }
+
+                roomCapabilities.supportedVersion.forEach {
+                    genericWithValueItem {
+                        id("room_version_${it.version}")
+                        title(it.version)
+                        value(
+                                host.stringProvider.getString(
+                                        when (it.status) {
+                                            RoomVersionStatus.STABLE   -> R.string.settings_server_room_version_stable
+                                            RoomVersionStatus.UNSTABLE -> R.string.settings_server_room_version_unstable
+                                        }
+                                )
+                        )
+                    }
+                }
+            }
+        }
     }
 }

vector/src/main/res/layout/bottom_sheet_tombstone_join.xml

@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:background="?colorSurface"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <TextView
+        android:id="@+id/headerText"
+        style="@style/Widget.Vector.TextView.Subtitle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:layout_marginBottom="12dp"
+        android:gravity="center"
+        android:text="@string/joining_replacement_room"
+        android:textColor="?vctr_content_primary"
+        android:textStyle="bold"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <TextView
+        android:id="@+id/descriptionText"
+        style="@style/Widget.Vector.TextView.Subtitle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginBottom="20dp"
+        android:gravity="center"
+        android:textColor="?vctr_content_secondary"
+        app:layout_constraintBottom_toTopOf="@id/joinInfoHelpText"
+        app:layout_constraintTop_toBottomOf="@id/headerText"
+        app:layout_constraintVertical_bias="1"
+        tools:text="@string/it_may_take_some_time" />
+
+    <im.vector.app.core.platform.ButtonStateView
+        android:id="@+id/roomUpgradeButton"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:layout_marginTop="8dp"
+        android:layout_marginBottom="@dimen/layout_vertical_margin_big"
+        app:bsv_button_text="@string/join"
+        app:bsv_loaded_image_src="@drawable/ic_tick"
+        app:bsv_use_flat_button="true" />
+
+</LinearLayout>

vector/src/main/res/layout/item_generic_progress.xml

@@ -0,0 +1,6 @@
+<ProgressBar xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/genericProgressBar"
+    style="?android:attr/progressBarStyleHorizontal"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_margin="8dp" />

vector/src/main/res/layout/item_timeline_event_create.xml

@@ -10,7 +10,7 @@
         style="@style/Widget.Vector.TextView.Body"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:layout_marginStart="16dp"
+        android:layout_marginStart="0dp"
         android:layout_marginTop="16dp"
         android:layout_marginBottom="16dp"
         android:background="?vctr_keys_backup_banner_accent_color"
@@ -18,7 +18,7 @@
         android:gravity="center|start"
         android:minHeight="80dp"
         android:padding="16dp"
-        app:drawableStartCompat="@drawable/error"
+        app:drawableStartCompat="@drawable/ic_warning_badge"
         tools:text="This room is continuation…" />
 
 </FrameLayout>

vector/src/main/res/layout/view_notification_area.xml

@@ -1,38 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 
-<merge xmlns:android="http://schemas.android.com/apk/res/android"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
+    android:background="?vctr_keys_backup_banner_accent_color"
     android:minHeight="48dp"
-    tools:parentTag="android.widget.RelativeLayout">
+    android:orientation="horizontal"
-
+    android:padding="16dp">
-    <View
-        android:layout_width="match_parent"
-        android:layout_height="1dp"
-        android:background="?vctr_list_separator" />
 
     <ImageView
         android:id="@+id/roomNotificationIcon"
         android:layout_width="32dp"
         android:layout_height="32dp"
-        android:layout_centerVertical="true"
+        android:layout_gravity="top"
-        android:layout_marginStart="24dp"
         android:importantForAccessibility="no"
         android:padding="5dp"
-        tools:src="@drawable/error" />
+        tools:src="@drawable/ic_warning_badge" />
 
     <TextView
         android:id="@+id/roomNotificationMessage"
         style="@style/Widget.Vector.TextView.Body"
-        android:layout_width="wrap_content"
+        android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:layout_centerVertical="true"
+        android:layout_gravity="center_vertical"
-        android:layout_marginStart="64dp"
+        android:paddingStart="4dp"
-        android:layout_marginEnd="16dp"
+        android:paddingEnd="0dp"
         android:accessibilityLiveRegion="polite"
-        android:gravity="center"
+        android:gravity="start"
         android:textColor="?vctr_content_primary"
         tools:text="@string/room_do_not_have_permission_to_post" />
 
-</merge>
+</LinearLayout>

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

@@ -926,7 +926,7 @@
     <string name="room_resend_unsent_messages">Resend unsent messages</string>
     <string name="room_delete_unsent_messages">Delete unsent messages</string>
     <string name="room_message_file_not_found">File not found</string>
-    <string name="room_do_not_have_permission_to_post">You do not have permission to post to this room</string>
+    <string name="room_do_not_have_permission_to_post">You do not have permission to post to this room.</string>
     <plurals name="room_new_messages_notification">
         <item quantity="one">%d new message</item>
         <item quantity="other">%d new messages</item>
@@ -1820,7 +1820,7 @@
 
     <string name="error_empty_field_enter_user_name">Please enter a username.</string>
     <string name="error_empty_field_your_password">Please enter your password.</string>
-    <string name="room_tombstone_versioned_description">This room has been replaced and is no longer active</string>
+    <string name="room_tombstone_versioned_description">This room has been replaced and is no longer active.</string>
     <string name="room_tombstone_continuation_link">The conversation continues here</string>
     <string name="room_tombstone_continuation_description">This room is a continuation of another conversation</string>
     <string name="room_tombstone_predecessor_link">Click here to see older messages</string>
@@ -2735,6 +2735,11 @@
     <string name="settings_server_upload_size_title">Server file upload limit</string>
     <string name="settings_server_upload_size_content">Your homeserver accepts attachments (files, media, etc.) with a size up to %s.</string>
     <string name="settings_server_upload_size_unknown">The limit is unknown.</string>
+    <!-- Only visible in developer mode-->
+    <string name="settings_server_room_versions">Room Versions 🕶</string>
+    <string name="settings_server_default_room_version">Default Version</string>
+    <string name="settings_server_room_version_stable">stable</string>
+    <string name="settings_server_room_version_unstable">unstable</string>
 
     <string name="settings_failed_to_get_crypto_device_info">No cryptographic information available</string>
 
@@ -3295,6 +3300,7 @@
     <string name="command_description_create_space">Create a Space</string>
     <string name="command_description_join_space">Join the Space with the given id</string>
     <string name="command_description_leave_room">Leave room with given id (or current room if null)</string>
+    <string name="command_description_upgrade_room">Upgrades a room to a new version</string>
 
     <string name="event_status_a11y_sending">Sending</string>
     <string name="event_status_a11y_sent">Sent</string>
@@ -3406,4 +3412,19 @@
 
     <string name="teammate_spaces_arent_quite_ready">"Teammate spaces aren’t quite ready but you can still give them a try"</string>
     <string name="teammate_spaces_might_not_join">"At the moment people might not be able to join any private rooms you make.\n\nWe’ll be improving this as part of the beta, but just wanted to let you know."</string>
-</resources>
+
+    <string name="joining_replacement_room">Join replacement room</string>
+    <string name="it_may_take_some_time">Please be patient, it may take some time.</string>
+
+
+    <string name="upgrade">Upgrade</string>
+    <string name="upgrade_public_room">Upgrade public room</string>
+    <string name="upgrade_private_room">Upgrade private room</string>
+    <string name="upgrade_room_warning">Upgrading a room is an advanced action and is usually recommended when a room is unstable due to bugs, missing features or security vulnerabilities.\nThis usually only affects how the room is processed on the server.</string>
+    <string name="upgrade_public_room_from_to">You\'ll upgrade this room from %s to %s.</string>
+    <string name="upgrade_room_auto_invite">Automatically invite users</string>
+    <string name="upgrade_room_update_parent_sapce">Automatically update space parent</string>
+    <string name="upgrade_room_update_parent">Automatically update parent space</string>
+    <string name="upgrade_room_no_power_to_manage">You need permission to upgrade a room</string>
+
+ </resources>