From 31f53d27c164347a48836f068625294e02a97ed9 Mon Sep 17 00:00:00 2001
From: Bruno Windels <274386+bwindels@users.noreply.github.com>
Date: Fri, 25 Nov 2022 11:51:22 +0100
Subject: [PATCH] emit update from datetile when date might have changed

---
 .../session/room/timeline/TilesCollection.js       | 14 ++------------
 src/domain/session/room/timeline/tiles/DateTile.ts |  5 ++++-
 2 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/src/domain/session/room/timeline/TilesCollection.js b/src/domain/session/room/timeline/TilesCollection.js
index e4ed9d24..6652e89c 100644
--- a/src/domain/session/room/timeline/TilesCollection.js
+++ b/src/domain/session/room/timeline/TilesCollection.js
@@ -151,7 +151,6 @@ export class TilesCollection extends BaseObservableList {
     }
 
     _evaluateDateHeaderAtIdx(tileIdx) {
-        //console.log("_evaluateDateHeaderAtIdx", tileIdx);
         // consider two tiles after the inserted tile, because
         // the first of the two tiles may be a DateTile in which case,
         // we remove it after looking at the needsDateSeparator prop of the
@@ -167,25 +166,16 @@ export class TilesCollection extends BaseObservableList {
             const tile = this._tiles[idx];
             const prevTile = idx > 0 ? this._tiles[idx - 1] : undefined;
             const hasDateSeparator = prevTile?.shape === TileShape.DateHeader;
-            if (tile.needsDateSeparator) {
-                if (hasDateSeparator) {
-                    // TODO: replace this by return UpdateAction from updateNextSibling
-                    // and do this in onAdd
-                    //console.log("    update", idx - 1, prevTile?.shape, prevTile?.eventId);
-                    this.emitUpdate(idx - 1, prevTile, "date");
-                } else {
-                    //console.log("    add", idx, tile.shape, tile.eventId);
+            if (tile.needsDateSeparator && !hasDateSeparator) {
                     // adding a tile shift all the indices we need to consider
                     // especially given we consider removals for the tile that
                     // comes after a datetile
                     tileIdx += 1;
                     this._addTileAt(idx, tile.createDateSeparator());
-                }
-            } else if (hasDateSeparator) {
+            } else if (!tile.needsDateSeparator && hasDateSeparator) {
                 // this is never triggered because needsDateSeparator is not cleared
                 // when loading more items because we don't do anything once the
                 // direct sibling is a DateTile
-                //console.log("    remove", idx -1, prevTile?.shape, prevTile?.eventId);
                 this._removeTile(idx - 1, prevTile);
             }
         }
diff --git a/src/domain/session/room/timeline/tiles/DateTile.ts b/src/domain/session/room/timeline/tiles/DateTile.ts
index 92bd42e5..4e7cbda2 100644
--- a/src/domain/session/room/timeline/tiles/DateTile.ts
+++ b/src/domain/session/room/timeline/tiles/DateTile.ts
@@ -130,8 +130,11 @@ export class DateTile extends ViewModel implements ITile<BaseEventEntry> {
         // TODO: next can be undefined when a pending event is removed
         // TODO: we need a way to remove this date header
         this._firstTileInDay = next!;
+        const prevDateString = this._dateString;
         this._dateString = undefined;
-        // TODO: do we need to reevaluate our date here and emit an update?
+        if (prevDateString && prevDateString !== this.date) {
+            this._emitUpdate?.(this, "date");
+        }
     }
 
     notifyVisible(): void {