Show Encryption Authenticity warnings on messages in the timeline. (#3051)

* Initial implementation.

* Add developer option for showing timeline item authenticity.

* Refactor code to use new SendInfo.Status.

---------

Co-authored-by: Doug <douglase@element.io>

ElementX/Sources/Services/Timeline/TimelineItemContent/EncryptionAuthenticity.swift

@@ -0,0 +1,74 @@
+//
+// Copyright 2024 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
+import MatrixRustSDK
+
+/// Represents and issue with a timeline item's authenticity such as coming from an
+/// unsigned session or being sent unencrypted in an encrypted room. See Rust's
+/// `ShieldStateCode` for more information about the meaning of the cases.
+enum EncryptionAuthenticity: Hashable {
+    enum Color { case red, gray }
+    
+    case notGuaranteed(color: Color)
+    case unknownDevice(color: Color)
+    case unsignedDevice(color: Color)
+    case unverifiedIdentity(color: Color)
+    case sentInClear(color: Color)
+    
+    var message: String {
+        switch self {
+        case .notGuaranteed:
+            L10n.eventShieldReasonAuthenticityNotGuaranteed
+        case .unknownDevice:
+            L10n.eventShieldReasonUnknownDevice
+        case .unsignedDevice:
+            L10n.eventShieldReasonUnsignedDevice
+        case .unverifiedIdentity:
+            L10n.eventShieldReasonUnverifiedIdentity
+        case .sentInClear:
+            L10n.eventShieldReasonSentInClear
+        }
+    }
+}
+
+extension EncryptionAuthenticity {
+    init?(shieldState: ShieldState) {
+        switch shieldState {
+        case .red(let code, _):
+            self.init(shieldStateCode: code, color: .red)
+        case .grey(let code, _):
+            self.init(shieldStateCode: code, color: .gray)
+        case .none:
+            return nil
+        }
+    }
+    
+    init(shieldStateCode: ShieldStateCode, color: EncryptionAuthenticity.Color) {
+        switch shieldStateCode {
+        case .authenticityNotGuaranteed:
+            self = .notGuaranteed(color: color)
+        case .unknownDevice:
+            self = .unknownDevice(color: color)
+        case .unsignedDevice:
+            self = .unsignedDevice(color: color)
+        case .unverifiedIdentity:
+            self = .unverifiedIdentity(color: color)
+        case .sentInClear:
+            self = .sentInClear(color: color)
+        }
+    }
+}

ElementX/Sources/Services/Timeline/TimelineItemContent/RoomTimelineItemProperties.swift

@@ -24,6 +24,8 @@ struct RoomTimelineItemProperties: Hashable {
     var reactions: [AggregatedReaction] = []
     /// The delivery status for this item. If a sent message is echoed the value is nil.
     var deliveryStatus: TimelineItemDeliveryStatus?
-    /// The read receipts of the item, ordered from newest to oldest
+    /// The read receipts of the item, ordered from newest to oldest.
     var orderedReadReceipts: [ReadReceipt] = []
+    /// Authenticity warnings for item's sent in encrypted rooms.
+    var encryptionAuthenticity: EncryptionAuthenticity?
 }