Extract MessageComposerContext class from MessageComposerPresenter (#876)

When sending "Composer" analytics from screens other than the composer's (e.g. send location from map) we need to know the composer's mode in order to properly fill the analytics event. `MessageComposerContext` hoists this state so that other presenters can also read it.

Related to:
element-hq/element-meta#1674
element-hq/element-meta#1682

Author: Marco Romano

features/messages/api/build.gradle.kts

@@ -25,4 +25,5 @@ android {
 dependencies {
     implementation(projects.libraries.architecture)
     implementation(projects.libraries.matrix.api)
+    api(projects.libraries.textcomposer)
 }

features/messages/api/src/main/kotlin/io/element/android/features/messages/api/MessageComposerContext.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2023 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 io.element.android.features.messages.api
+
+import io.element.android.libraries.textcomposer.MessageComposerMode
+
+/**
+ * Hoist-able state of the message composer.
+ *
+ * Typical use case is inside other presenters, to know if
+ * the composer is in a thread, if it's editing a message, etc.
+ */
+interface MessageComposerContext {
+    val composerMode: MessageComposerMode
+}

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/messagecomposer/MessageComposerContextImpl.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2023 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 io.element.android.features.messages.impl.messagecomposer
+
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import com.squareup.anvil.annotations.ContributesBinding
+import io.element.android.features.messages.api.MessageComposerContext
+import io.element.android.libraries.di.RoomScope
+import io.element.android.libraries.di.SingleIn
+import io.element.android.libraries.textcomposer.MessageComposerMode
+import javax.inject.Inject
+
+@SingleIn(RoomScope::class)
+@ContributesBinding(RoomScope::class)
+class MessageComposerContextImpl @Inject constructor() : MessageComposerContext {
+    override var composerMode: MessageComposerMode by mutableStateOf(MessageComposerMode.Normal(""))
+        internal set
+}

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/messagecomposer/MessageComposerPresenter.kt

@@ -64,6 +64,7 @@ class MessageComposerPresenter @Inject constructor(
     private val mediaSender: MediaSender,
     private val snackbarDispatcher: SnackbarDispatcher,
     private val analyticsService: AnalyticsService,
+    private val messageComposerContext: MessageComposerContextImpl,
 ) : Presenter<MessageComposerState> {
 
     @SuppressLint("UnsafeOptInUsageError")
@@ -96,14 +97,11 @@ class MessageComposerPresenter @Inject constructor(
         val text: MutableState<StableCharSequence> = remember {
             mutableStateOf(StableCharSequence(""))
         }
-        val composerMode: MutableState<MessageComposerMode> = rememberSaveable {
-            mutableStateOf(MessageComposerMode.Normal(""))
-        }
 
         var showAttachmentSourcePicker: Boolean by remember { mutableStateOf(false) }
 
-        LaunchedEffect(composerMode.value) {
-            when (val modeValue = composerMode.value) {
+        LaunchedEffect(messageComposerContext.composerMode) {
+            when (val modeValue = messageComposerContext.composerMode) {
                 is MessageComposerMode.Edit -> text.value = modeValue.defaultContent.toStableCharSequence()
                 else -> Unit
             }
@@ -125,17 +123,21 @@ class MessageComposerPresenter @Inject constructor(
                 is MessageComposerEvents.UpdateText -> text.value = event.text.toStableCharSequence()
                 MessageComposerEvents.CloseSpecialMode -> {
                     text.value = "".toStableCharSequence()
-                    composerMode.setToNormal()
+                    messageComposerContext.composerMode = MessageComposerMode.Normal("")
                 }
 
-                is MessageComposerEvents.SendMessage -> appCoroutineScope.sendMessage(event.message, composerMode, text)
+                is MessageComposerEvents.SendMessage -> appCoroutineScope.sendMessage(
+                    text = event.message,
+                    updateComposerMode = { messageComposerContext.composerMode = it },
+                    textState = text
+                )
                 is MessageComposerEvents.SetMode -> {
-                    composerMode.value = event.composerMode
+                    messageComposerContext.composerMode = event.composerMode
                     analyticsService.capture(
                         Composer(
-                            inThread = false,
-                            isEditing = composerMode.value is MessageComposerMode.Edit,
-                            isReply = composerMode.value is MessageComposerMode.Reply,
+                            inThread = messageComposerContext.composerMode.inThread,
+                            isEditing = messageComposerContext.composerMode.isEditing,
+                            isReply = messageComposerContext.composerMode.isReply,
                             isLocation = false,
                         )
                     )
@@ -171,7 +173,7 @@ class MessageComposerPresenter @Inject constructor(
             text = text.value,
             isFullScreen = isFullScreen.value,
             hasFocus = hasFocus.value,
-            mode = composerMode.value,
+            mode = messageComposerContext.composerMode,
             showAttachmentSourcePicker = showAttachmentSourcePicker,
             attachmentsState = attachmentsState.value,
             eventSink = ::handleEvents
@@ -184,31 +186,30 @@ class MessageComposerPresenter @Inject constructor(
         }
     }
 
-    private fun MutableState<MessageComposerMode>.setToNormal() {
-        value = MessageComposerMode.Normal("")
-    }
-
-    private fun CoroutineScope.sendMessage(text: String, composerMode: MutableState<MessageComposerMode>, textState: MutableState<StableCharSequence>) =
-        launch {
-            val capturedMode = composerMode.value
-            // Reset composer right away
-            textState.value = "".toStableCharSequence()
-            composerMode.setToNormal()
-            when (capturedMode) {
-                is MessageComposerMode.Normal -> room.sendMessage(text)
-                is MessageComposerMode.Edit -> {
-                    val eventId = capturedMode.eventId
-                    val transactionId = capturedMode.transactionId
-                    room.editMessage(eventId, transactionId, text)
-                }
-
-                is MessageComposerMode.Quote -> TODO()
-                is MessageComposerMode.Reply -> room.replyMessage(
-                    capturedMode.eventId,
-                    text
-                )
+    private fun CoroutineScope.sendMessage(
+        text: String,
+        updateComposerMode: (newComposerMode: MessageComposerMode) -> Unit,
+        textState: MutableState<StableCharSequence>
+    ) = launch {
+        val capturedMode = messageComposerContext.composerMode
+        // Reset composer right away
+        textState.value = "".toStableCharSequence()
+        updateComposerMode(MessageComposerMode.Normal(""))
+        when (capturedMode) {
+            is MessageComposerMode.Normal -> room.sendMessage(text)
+            is MessageComposerMode.Edit -> {
+                val eventId = capturedMode.eventId
+                val transactionId = capturedMode.transactionId
+                room.editMessage(eventId, transactionId, text)
             }
+
+            is MessageComposerMode.Quote -> TODO()
+            is MessageComposerMode.Reply -> room.replyMessage(
+                capturedMode.eventId,
+                text
+            )
         }
+    }
 
     private fun CoroutineScope.sendAttachment(
         attachment: Attachment,

features/messages/impl/src/test/kotlin/io/element/android/features/messages/MessagesPresenterTest.kt

@@ -31,6 +31,7 @@ import io.element.android.features.messages.impl.MessagesPresenter
 import io.element.android.features.messages.impl.actionlist.ActionListPresenter
 import io.element.android.features.messages.impl.actionlist.ActionListState
 import io.element.android.features.messages.impl.actionlist.model.TimelineItemAction
+import io.element.android.features.messages.impl.messagecomposer.MessageComposerContextImpl
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerEvents
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerPresenter
 import io.element.android.features.messages.impl.timeline.TimelinePresenter
@@ -568,6 +569,7 @@ class MessagesPresenterTest {
             mediaSender = MediaSender(FakeMediaPreProcessor(), matrixRoom),
             snackbarDispatcher = SnackbarDispatcher(),
             analyticsService = FakeAnalyticsService(),
+            messageComposerContext = MessageComposerContextImpl(),
         )
         val timelinePresenter = TimelinePresenter(
             timelineItemsFactory = aTimelineItemsFactory(),

features/messages/impl/src/test/kotlin/io/element/android/features/messages/textcomposer/MessageComposerPresenterTest.kt

@@ -26,6 +26,7 @@ import app.cash.turbine.test
 import com.google.common.truth.Truth.assertThat
 import io.element.android.features.analytics.test.FakeAnalyticsService
 import io.element.android.features.messages.impl.messagecomposer.AttachmentsState
+import io.element.android.features.messages.impl.messagecomposer.MessageComposerContextImpl
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerEvents
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerPresenter
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerState
@@ -503,7 +504,8 @@ class MessageComposerPresenterTest {
         localMediaFactory,
         MediaSender(mediaPreProcessor, room),
         snackbarDispatcher,
-        FakeAnalyticsService()
+        FakeAnalyticsService(),
+        MessageComposerContextImpl(),
     )
 }
 

features/messages/test/build.gradle.kts

@@ -0,0 +1,27 @@
+/*
+ * 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.
+ */
+
+plugins {
+    id("io.element.android-library")
+}
+
+android {
+    namespace = "io.element.android.features.messages.test"
+}
+
+dependencies {
+    api(projects.features.messages.api)
+}

features/messages/test/src/main/kotlin/io/element/android/features/messages/test/MessageComposerContextFake.kt

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2023 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 io.element.android.features.messages.test
+
+import io.element.android.features.messages.api.MessageComposerContext
+import io.element.android.libraries.textcomposer.MessageComposerMode
+
+class MessageComposerContextFake(
+    override var composerMode: MessageComposerMode = MessageComposerMode.Normal(null)
+) : MessageComposerContext

libraries/textcomposer/src/main/kotlin/io/element/android/libraries/textcomposer/MessageComposerMode.kt

@@ -51,4 +51,13 @@ sealed interface MessageComposerMode : Parcelable {
             is Quote -> eventId
             is Reply -> eventId
         }
+
+    val isEditing: Boolean
+        get() = this is Edit
+
+    val isReply: Boolean
+        get() = this is Reply
+
+    val inThread: Boolean
+        get() = false // TODO
 }