Handle screenshot notifications

Session/Conversations/ConversationVC+Interaction.swift

@@ -653,6 +653,16 @@ extension ConversationVC : InputViewDelegate, MessageCellDelegate, ContextMenuAc
         audioRecorder?.stop()
         audioSession.endAudioActivity(recordVoiceMessageActivity)
     }
+    
+    // MARK: Screenshot Notifications
+    @objc func sendScreenshotNotificationIfNeeded() {
+        guard thread is TSContactThread else { return }
+        let message = DataExtractionNotification()
+        message.kind = .screenshot
+        Storage.write { transaction in
+            MessageSender.send(message, in: self.thread, using: transaction)
+        }
+    }
 
     // MARK: Requesting Permission
     func requestCameraPermissionIfNeeded() -> Bool {

Session/Conversations/ConversationVC.swift

@@ -184,6 +184,7 @@ final class ConversationVC : BaseVC, ConversationViewModelDelegate, OWSConversat
         notificationCenter.addObserver(self, selector: #selector(handleAudioDidFinishPlayingNotification(_:)), name: .SNAudioDidFinishPlaying, object: nil)
         notificationCenter.addObserver(self, selector: #selector(addOrRemoveBlockedBanner), name: NSNotification.Name(rawValue: kNSNotificationName_BlockListDidChange), object: nil)
         notificationCenter.addObserver(self, selector: #selector(handleGroupUpdatedNotification), name: .groupThreadUpdated, object: nil)
+        notificationCenter.addObserver(self, selector: #selector(sendScreenshotNotificationIfNeeded), name: UIApplication.userDidTakeScreenshotNotification, object: nil)
         // Mentions
         MentionsManager.populateUserPublicKeyCacheIfNeeded(for: thread.uniqueId!)
         // Draft

SessionMessagingKit/Sending & Receiving/Data Extraction/DataExtractionNotificationInfoMessage.swift

@@ -1,35 +1,29 @@
 
 @objc(SNDataExtractionNotificationInfoMessage)
 final class DataExtractionNotificationInfoMessage : TSInfoMessage {
-    private let kind: DataExtractionNotification.Kind
     
-    init(kind: DataExtractionNotification.Kind, timestamp: UInt64, thread: TSThread) {
-        self.kind = kind
-        let infoMessageType: TSInfoMessageType
-        switch kind {
-        case .screenshot: infoMessageType = .screenshotNotification
-        case .mediaSaved: infoMessageType = .mediaSavedNotification
-        }
-        super.init(timestamp: timestamp, in: thread, messageType: infoMessageType)
+    init(type: TSInfoMessageType, sentTimestamp: UInt64, thread: TSThread, referencedAttachmentTimestamp: UInt64?) {
+        super.init(timestamp: sentTimestamp, in: thread, messageType: type)
     }
     
     required init(coder: NSCoder) {
-        preconditionFailure("Not implemented.")
+        super.init(coder: coder)
     }
     
     required init(dictionary dictionaryValue: [String:Any]!) throws {
-        preconditionFailure("Not implemented.")
+        try super.init(dictionary: dictionaryValue)
     }
     
     override func previewText(with transaction: YapDatabaseReadTransaction) -> String {
         guard let thread = thread as? TSContactThread else { return "" } // Should never occur
         let sessionID = thread.contactIdentifier()
         let displayName = Storage.shared.getContact(with: sessionID)?.displayName(for: .regular) ?? sessionID
-        switch kind {
-        case .screenshot: return "\(displayName) took a screenshot."
-        case .mediaSaved:
-            // TODO: Use the timestamp and tell the user * which * media was saved
+        switch messageType {
+        case .screenshotNotification: return "\(displayName) took a screenshot."
+        case .mediaSavedNotification:
+            // TODO: Use referencedAttachmentTimestamp to tell the user * which * media was saved
             return "Media saved by \(displayName)."
+        default: preconditionFailure()
         }
     }
 }

SessionMessagingKit/Sending & Receiving/MessageReceiver+Handling.swift

@@ -108,7 +108,12 @@ extension MessageReceiver {
     // MARK: - Data Extraction Notification
     
     private static func handleDataExtractionNotification(_ message: DataExtractionNotification, using transaction: Any) {
-        
+        let transaction = transaction as! YapDatabaseReadWriteTransaction
+        guard message.groupPublicKey == nil,
+            let thread = TSContactThread.getWithContactId(message.sender!, transaction: transaction) else { return }
+        // TODO: Handle media saved type notifications
+        let message = DataExtractionNotificationInfoMessage(type: .screenshotNotification, sentTimestamp: message.sentTimestamp!, thread: thread, referencedAttachmentTimestamp: nil)
+        message.save(with: transaction)
     }