Introducing use case to check if an event can be redacted

vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/CheckIfCanRedactEventUseCase.kt

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2022 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.timeline.action
+
+import im.vector.app.core.di.ActiveSessionHolder
+import org.matrix.android.sdk.api.session.events.model.EventType
+import org.matrix.android.sdk.api.session.room.timeline.TimelineEvent
+import javax.inject.Inject
+
+class CheckIfCanRedactEventUseCase @Inject constructor(
+        private val activeSessionHolder: ActiveSessionHolder
+) {
+
+    fun execute(event: TimelineEvent, actionPermissions: ActionPermissions): Boolean {
+        // Only some event types are supported for the moment
+        val canRedactEventTypes = listOf(EventType.MESSAGE, EventType.STICKER) +
+                EventType.POLL_START + EventType.STATE_ROOM_BEACON_INFO
+        if (event.root.getClearType() !in canRedactEventTypes) return false
+        // Message sent by the current user can always be redacted
+        if (event.root.senderId == activeSessionHolder.getActiveSession().myUserId) return true
+        // Check permission for messages sent by other users
+        return actionPermissions.canRedact
+    }
+}

vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsViewModel.kt

@@ -82,6 +82,7 @@ class MessageActionsViewModel @AssistedInject constructor(
         private val pillsPostProcessorFactory: PillsPostProcessor.Factory,
         private val vectorPreferences: VectorPreferences,
         private val checkIfCanReplyEventUseCase: CheckIfCanReplyEventUseCase,
+        private val checkIfCanRedactEventUseCase: CheckIfCanRedactEventUseCase,
 ) : VectorViewModel<MessageActionState, MessageActionsAction, EmptyViewEvents>(initialState) {
 
     private val informationData = initialState.informationData
@@ -518,12 +519,7 @@ class MessageActionsViewModel @AssistedInject constructor(
     }
 
     private fun canRedact(event: TimelineEvent, actionPermissions: ActionPermissions): Boolean {
-        // Only event of type EventType.MESSAGE, EventType.STICKER and EventType.POLL_START are supported for the moment
-        if (event.root.getClearType() !in listOf(EventType.MESSAGE, EventType.STICKER) + EventType.POLL_START) return false
-        // Message sent by the current user can always be redacted
-        if (event.root.senderId == session.myUserId) return true
-        // Check permission for messages sent by other users
-        return actionPermissions.canRedact
+        return checkIfCanRedactEventUseCase.execute(event, actionPermissions)
     }
 
     private fun canRetry(event: TimelineEvent, actionPermissions: ActionPermissions): Boolean {

vector/src/test/java/im/vector/app/features/home/room/detail/timeline/action/CheckIfCanRedactEventUseCaseTest.kt

@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2022 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.timeline.action
+
+import im.vector.app.test.fakes.FakeActiveSessionHolder
+import io.mockk.mockk
+import org.amshove.kluent.shouldBe
+import org.junit.Test
+import org.matrix.android.sdk.api.session.events.model.Event
+import org.matrix.android.sdk.api.session.events.model.EventType
+import org.matrix.android.sdk.api.session.room.timeline.TimelineEvent
+
+class CheckIfCanRedactEventUseCaseTest {
+
+    private val fakeActiveSessionHolder = FakeActiveSessionHolder()
+
+    private val checkIfCanRedactEventUseCase = CheckIfCanRedactEventUseCase(
+            activeSessionHolder = fakeActiveSessionHolder.instance
+    )
+
+    @Test
+    fun `given an event which can be redacted and owned by user when use case executes then the result is true`() {
+        val canRedactEventTypes = listOf(EventType.MESSAGE, EventType.STICKER) +
+                EventType.POLL_START + EventType.STATE_ROOM_BEACON_INFO
+
+        canRedactEventTypes.forEach { eventType ->
+            val event = givenAnEvent(
+                    eventType = eventType,
+                    senderId = fakeActiveSessionHolder.fakeSession.myUserId
+            )
+
+            val actionPermissions = givenActionPermissions(canRedact = false)
+
+            val result = checkIfCanRedactEventUseCase.execute(event, actionPermissions)
+
+            result shouldBe true
+        }
+    }
+
+    @Test
+    fun `given redact permission and an event which can be redacted and sent by another user when use case executes then the result is true`() {
+        val event = givenAnEvent(
+                eventType = EventType.MESSAGE,
+                senderId = "user-id"
+        )
+
+        val actionPermissions = givenActionPermissions(canRedact = true)
+
+        val result = checkIfCanRedactEventUseCase.execute(event, actionPermissions)
+
+        result shouldBe true
+    }
+
+    @Test
+    fun `given an event which cannot be redacted when use case executes then the result is false`() {
+        val event = givenAnEvent(
+                eventType = EventType.CALL_ANSWER,
+                senderId = fakeActiveSessionHolder.fakeSession.myUserId
+        )
+
+        val actionPermissions = givenActionPermissions(canRedact = false)
+
+        val result = checkIfCanRedactEventUseCase.execute(event, actionPermissions)
+
+        result shouldBe false
+    }
+
+    @Test
+    fun `given missing redact permission and an event which can be redacted and sent by another user when use case executes then the result is false`() {
+        val event = givenAnEvent(
+                eventType = EventType.MESSAGE,
+                senderId = "user-id"
+        )
+
+        val actionPermissions = givenActionPermissions(canRedact = false)
+
+        val result = checkIfCanRedactEventUseCase.execute(event, actionPermissions)
+
+        result shouldBe false
+    }
+
+    private fun givenAnEvent(eventType: String, senderId: String): TimelineEvent {
+        val eventId = "event-id"
+        return TimelineEvent(
+                root = Event(
+                        eventId = eventId,
+                        type = eventType,
+                        senderId = senderId
+                ),
+                localId = 123L,
+                eventId = eventId,
+                displayIndex = 1,
+                ownedByThreadChunk = false,
+                senderInfo = mockk()
+        )
+    }
+
+    private fun givenActionPermissions(canRedact: Boolean): ActionPermissions {
+        return ActionPermissions(canRedact = canRedact)
+    }
+}