Show the date on a room when the last message is older than today. (#484)

* Format the last message date correctly.
* Update room cell layout - fixes an issue where the longer the date got the smaller the last message width was.

ElementX/Sources/Other/Extensions/Date.swift

@@ -0,0 +1,43 @@
+//
+// Copyright 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.
+//
+
+import Foundation
+
+extension Date {
+    /// The date formatted with the minimal necessary units given how long ago it occurred.
+    func formattedMinimal() -> String {
+        let calendar = Calendar.current
+        
+        if calendar.isDateInToday(self) {
+            // Just the time if it was today.
+            return formatted(date: .omitted, time: .shortened)
+        } else if calendar.isDateInYesterday(self) {
+            // Simply "Yesterday" if it was yesterday.
+            return formatted(Date.RelativeFormatStyle(presentation: .named, capitalizationContext: .beginningOfSentence))
+        } else if let sixDaysAgo = calendar.date(byAdding: .day, value: -6, to: calendar.startOfDay(for: .now)),
+                  sixDaysAgo <= self {
+            // The named day if it was in the last 6 days.
+            return formatted(.dateTime.weekday(.wide))
+        } else if let oneYearAgo = calendar.date(byAdding: .year, value: -1, to: .now),
+                  oneYearAgo <= self {
+            // The day and month if it was in the last 6 days.
+            return formatted(.dateTime.day().month())
+        } else {
+            // The day, month and year if it is any older.
+            return formatted(.dateTime.year().day().month())
+        }
+    }
+}