Cleanup and doc

vector/src/main/java/im/vector/riotx/core/extensions/Collections.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2020 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.riotx.core.extensions
+
+inline fun <reified T> List<T>.nextOrNull(index: Int) = getOrNull(index + 1)
+inline fun <reified T> List<T>.prevOrNull(index: Int) = getOrNull(index - 1)

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

@@ -35,6 +35,7 @@ import im.vector.matrix.android.api.session.room.timeline.TimelineEvent
 import im.vector.riotx.core.date.VectorDateFormatter
 import im.vector.riotx.core.epoxy.LoadingItem_
 import im.vector.riotx.core.extensions.localDateTime
+import im.vector.riotx.core.extensions.nextOrNull
 import im.vector.riotx.features.home.room.detail.RoomDetailAction
 import im.vector.riotx.features.home.room.detail.RoomDetailViewState
 import im.vector.riotx.features.home.room.detail.UnreadState
@@ -45,7 +46,6 @@ import im.vector.riotx.features.home.room.detail.timeline.helper.ReadMarkerVisib
 import im.vector.riotx.features.home.room.detail.timeline.helper.TimelineEventDiffUtilCallback
 import im.vector.riotx.features.home.room.detail.timeline.helper.TimelineEventVisibilityStateChangedListener
 import im.vector.riotx.features.home.room.detail.timeline.helper.TimelineMediaSizeProvider
-import im.vector.riotx.features.home.room.detail.timeline.helper.nextOrNull
 import im.vector.riotx.features.home.room.detail.timeline.item.BaseEventItem
 import im.vector.riotx.features.home.room.detail.timeline.item.BasedMergedItem
 import im.vector.riotx.features.home.room.detail.timeline.item.DaySeparatorItem

vector/src/main/java/im/vector/riotx/features/home/room/detail/timeline/factory/MergedHeaderItemFactory.kt

@@ -22,7 +22,7 @@ import im.vector.matrix.android.api.session.room.model.create.RoomCreateContent
 import im.vector.matrix.android.api.session.room.timeline.TimelineEvent
 import im.vector.matrix.android.internal.crypto.MXCRYPTO_ALGORITHM_MEGOLM
 import im.vector.matrix.android.internal.crypto.model.event.EncryptionEventContent
-import im.vector.riotx.core.di.ActiveSessionHolder
+import im.vector.riotx.core.extensions.prevOrNull
 import im.vector.riotx.features.home.AvatarRenderer
 import im.vector.riotx.features.home.room.detail.timeline.TimelineEventController
 import im.vector.riotx.features.home.room.detail.timeline.helper.AvatarSizeProvider
@@ -37,15 +37,15 @@ import im.vector.riotx.features.home.room.detail.timeline.item.MergedRoomCreatio
 import im.vector.riotx.features.home.room.detail.timeline.item.MergedRoomCreationItem_
 import javax.inject.Inject
 
-class MergedHeaderItemFactory @Inject constructor(private val sessionHolder: ActiveSessionHolder,
+class MergedHeaderItemFactory @Inject constructor(private val avatarRenderer: AvatarRenderer,
-                                                  private val avatarRenderer: AvatarRenderer,
                                                   private val avatarSizeProvider: AvatarSizeProvider) {
 
     private val collapsedEventIds = linkedSetOf<Long>()
     private val mergeItemCollapseStates = HashMap<Long, Boolean>()
 
     /**
-     * Note: nextEvent is an older event than event
+     * @param nextEvent is an older event than event
+     * @param items all known items, sorted from newer event to oldest event
      */
     fun create(event: TimelineEvent,
                nextEvent: TimelineEvent?,
@@ -127,9 +127,9 @@ class MergedHeaderItemFactory @Inject constructor(private val sessionHolder: Act
                                                eventIdToHighlight: String?,
                                                requestModelBuild: () -> Unit,
                                                callback: TimelineEventController.Callback?): MergedRoomCreationItem_? {
-        var prevEvent = if (currentPosition > 0) items[currentPosition - 1] else null
+        var prevEvent = items.prevOrNull(currentPosition)
         var tmpPos = currentPosition - 1
-        val mergedEvents = ArrayList<TimelineEvent>().also { it.add(event) }
+        val mergedEvents = mutableListOf(event)
         var hasEncryption = false
         var encryptionAlgorithm: String? = null
         while (prevEvent != null && prevEvent.isRoomConfiguration(null)) {
@@ -139,7 +139,7 @@ class MergedHeaderItemFactory @Inject constructor(private val sessionHolder: Act
             }
             mergedEvents.add(prevEvent)
             tmpPos--
-            prevEvent = if (tmpPos >= 0) items[tmpPos] else null
+            prevEvent = items.getOrNull(tmpPos)
         }
         return if (mergedEvents.size > 2) {
             var highlighted = false

vector/src/main/java/im/vector/riotx/features/home/room/detail/timeline/helper/TimelineDisplayableEvents.kt

@@ -106,11 +106,3 @@ fun List<TimelineEvent>.prevSameTypeEvents(index: Int, minSize: Int): List<Timel
             .nextSameTypeEvents(0, minSize)
             .reversed()
 }
-
-fun List<TimelineEvent>.nextOrNull(index: Int): TimelineEvent? {
-    return if (index >= size - 1) {
-        null
-    } else {
-        subList(index + 1, this.size).firstOrNull()
-    }
-}