deleted message UI in conversation screen

Session.xcodeproj/project.pbxproj

@@ -137,6 +137,7 @@
 		76C87F19181EFCE600C4ACAB /* MediaPlayer.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 76C87F18181EFCE600C4ACAB /* MediaPlayer.framework */; };
 		76EB054018170B33006006FC /* AppDelegate.m in Sources */ = {isa = PBXBuildFile; fileRef = 76EB03C318170B33006006FC /* AppDelegate.m */; };
 		7B4C75CB26B37E0F0000AC89 /* UnsendRequest.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B4C75CA26B37E0F0000AC89 /* UnsendRequest.swift */; };
+		7B4C75CD26BB92060000AC89 /* DeletedMessageView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B4C75CC26BB92060000AC89 /* DeletedMessageView.swift */; };
 		7BC01A3E241F40AB00BC7C55 /* NotificationServiceExtension.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BC01A3D241F40AB00BC7C55 /* NotificationServiceExtension.swift */; };
 		7BC01A42241F40AB00BC7C55 /* SessionNotificationServiceExtension.appex in Embed App Extensions */ = {isa = PBXBuildFile; fileRef = 7BC01A3B241F40AB00BC7C55 /* SessionNotificationServiceExtension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
 		7BDCFC08242186E700641C39 /* NotificationServiceExtensionContext.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BDCFC07242186E700641C39 /* NotificationServiceExtensionContext.swift */; };
@@ -1099,6 +1100,7 @@
 		76EB03C218170B33006006FC /* AppDelegate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = AppDelegate.h; sourceTree = "<group>"; };
 		76EB03C318170B33006006FC /* AppDelegate.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = AppDelegate.m; sourceTree = "<group>"; };
 		7B4C75CA26B37E0F0000AC89 /* UnsendRequest.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UnsendRequest.swift; sourceTree = "<group>"; };
+		7B4C75CC26BB92060000AC89 /* DeletedMessageView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DeletedMessageView.swift; sourceTree = "<group>"; };
 		7BC01A3B241F40AB00BC7C55 /* SessionNotificationServiceExtension.appex */ = {isa = PBXFileReference; explicitFileType = "wrapper.app-extension"; includeInIndex = 0; path = SessionNotificationServiceExtension.appex; sourceTree = BUILT_PRODUCTS_DIR; };
 		7BC01A3D241F40AB00BC7C55 /* NotificationServiceExtension.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NotificationServiceExtension.swift; sourceTree = "<group>"; };
 		7BC01A3F241F40AB00BC7C55 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
@@ -2089,6 +2091,7 @@
 				B849789525D4A2F500D0D0B3 /* LinkPreviewView.swift */,
 				B8D84EA225DF745A005A043E /* LinkPreviewState.swift */,
 				B8EB20EF2640F7F000773E52 /* OpenGroupInvitationView.swift */,
+				7B4C75CC26BB92060000AC89 /* DeletedMessageView.swift */,
 			);
 			path = "Content Views";
 			sourceTree = "<group>";
@@ -4903,6 +4906,7 @@
 				B8D0A25025E3678700C1835E /* LinkDeviceVC.swift in Sources */,
 				3496957321A301A100DCFE74 /* OWSBackupJob.m in Sources */,
 				B894D0752339EDCF00B4D94D /* NukeDataModal.swift in Sources */,
+				7B4C75CD26BB92060000AC89 /* DeletedMessageView.swift in Sources */,
 				B897621C25D201F7004F83B2 /* ScrollToBottomButton.swift in Sources */,
 				346B66311F4E29B200E5122F /* CropScaleImageViewController.swift in Sources */,
 				45E5A6991F61E6DE001E4A8A /* MarqueeLabel.swift in Sources */,

Session/Conversations/ConversationViewItem.h

@@ -15,6 +15,7 @@ typedef NS_ENUM(NSInteger, OWSMessageCellType) {
     OWSMessageCellType_GenericAttachment,
     OWSMessageCellType_MediaMessage,
     OWSMessageCellType_OversizeTextDownloading,
+    OWSMessageCellType_DeletedMessage
 };
 
 NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType);

Session/Conversations/ConversationViewItem.m

@@ -471,6 +471,11 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType)
 
     TSMessage *message = (TSMessage *)self.interaction;
     
+    if (message.isDeleted) {
+        self.messageCellType = OWSMessageCellType_DeletedMessage;
+        return;
+    }
+
     // Check for quoted replies _before_ media album handling,
     // since that logic may exit early.
     if (message.quotedMessage) {

Session/Conversations/Message Cells/Content Views/DeletedMessageView.swift

@@ -0,0 +1,51 @@
+
+final class DeletedMessageView : UIView {
+    private let viewItem: ConversationViewItem
+    private let textColor: UIColor
+    
+    // MARK: Settings
+    private static let iconSize: CGFloat = 18
+    private static let iconImageViewSize: CGFloat = 30
+    
+    // MARK: Lifecycle
+    init(viewItem: ConversationViewItem, textColor: UIColor) {
+        self.viewItem = viewItem
+        self.textColor = textColor
+        super.init(frame: CGRect.zero)
+        setUpViewHierarchy()
+    }
+    
+    override init(frame: CGRect) {
+        preconditionFailure("Use init(viewItem:textColor:) instead.")
+    }
+    
+    required init?(coder: NSCoder) {
+        preconditionFailure("Use init(viewItem:textColor:) instead.")
+    }
+    
+    private func setUpViewHierarchy() {
+        // Image view
+        let iconSize = DeletedMessageView.iconSize
+        let icon = UIImage(named: "ic_trash")?.withTint(textColor)?.resizedImage(to: CGSize(width: iconSize, height: iconSize))
+        let imageView = UIImageView(image: icon)
+        imageView.contentMode = .center
+        let iconImageViewSize = DeletedMessageView.iconImageViewSize
+        imageView.set(.width, to: iconImageViewSize)
+        imageView.set(.height, to: iconImageViewSize)
+        // Body label
+        let titleLabel = UILabel()
+        titleLabel.lineBreakMode = .byTruncatingTail
+        titleLabel.text = "This message has been deleted."
+        titleLabel.textColor = textColor
+        titleLabel.font = .systemFont(ofSize: Values.smallFontSize)
+        // Stack view
+        let stackView = UIStackView(arrangedSubviews: [ imageView, titleLabel ])
+        stackView.axis = .horizontal
+        stackView.alignment = .center
+        stackView.isLayoutMarginsRelativeArrangement = true
+        stackView.layoutMargins = UIEdgeInsets(top: 0, leading: 0, bottom: 0, trailing: 6)
+        addSubview(stackView)
+        stackView.pin(to: self, withInset: Values.smallSpacing)
+    }
+}
+

Session/Conversations/Message Cells/VisibleMessageCell.swift

@@ -389,6 +389,10 @@ final class VisibleMessageCell : MessageCell, LinkPreviewViewDelegate {
                 snContentView.addSubview(documentView)
                 documentView.pin(to: snContentView)
             }
+        case .deletedMessage:
+            let deletedMessageView = DeletedMessageView(viewItem: viewItem, textColor: bodyLabelTextColor)
+            snContentView.addSubview(deletedMessageView)
+            deletedMessageView.pin(to: snContentView)
         default: return
         }
     }

SessionMessagingKit/Messages/Signal/TSMessage.h

@@ -39,6 +39,7 @@ extern const NSUInteger kOversizeTextMessageSizeThreshold;
 @property (nonatomic, readonly, nullable) NSString *openGroupInvitationName;
 @property (nonatomic, readonly, nullable) NSString *openGroupInvitationURL;
 @property (nonatomic, nullable) NSString *serverHash;
+@property (nonatomic) BOOL isDeleted;
 
 - (instancetype)initInteractionWithTimestamp:(uint64_t)timestamp inThread:(TSThread *)thread NS_UNAVAILABLE;
 
@@ -82,6 +83,8 @@ extern const NSUInteger kOversizeTextMessageSizeThreshold;
 
 - (void)updateWithLinkPreview:(OWSLinkPreview *)linkPreview transaction:(YapDatabaseReadWriteTransaction *)transaction;
 
+- (void)updateForDeletionWithTransaction:(YapDatabaseReadWriteTransaction *)transaction;
+
 @end
 
 NS_ASSUME_NONNULL_END

SessionMessagingKit/Messages/Signal/TSMessage.m

@@ -86,6 +86,7 @@ const NSUInteger kOversizeTextMessageSizeThreshold = 2 * 1024;
     _openGroupInvitationName = openGroupInvitationName;
     _openGroupInvitationURL = openGroupInvitationURL;
     _serverHash = serverHash;
+    _isDeleted = false;
 
     return self;
 }
@@ -423,6 +424,23 @@ const NSUInteger kOversizeTextMessageSizeThreshold = 2 * 1024;
                              }];
 }
 
+- (void)updateForDeletionWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
+{
+    [self applyChangeToSelfAndLatestCopy:transaction
+                             changeBlock:^(TSMessage *message) {
+                                [message setBody:nil];
+                                [message setServerHash:nil];
+                                for (NSString *attachmentId in message.attachmentIds) {
+                                    TSAttachment *_Nullable attachment =
+                                        [TSAttachment fetchObjectWithUniqueID:attachmentId transaction:transaction];
+                                    if (attachment) {
+                                        [attachment removeWithTransaction:transaction];
+                                    }
+                                }
+                                [message setIsDeleted:true];
+                             }];
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

SessionMessagingKit/Sending & Receiving/MessageReceiver+Handling.swift

@@ -234,7 +234,7 @@ extension MessageReceiver {
             if let serverHash = messageToDelete.serverHash {
                 SnodeAPI.deleteMessage(publicKey: author, serverHashes: [serverHash]).retainUntilComplete()
             }
-            messageToDelete.remove(with: transaction)
+            messageToDelete.updateForDeletion(with: transaction)
         }
     }