Make link previews work again

Session/Signal/ConversationView/ConversationViewController.m

@@ -3753,22 +3753,29 @@ typedef enum : NSUInteger {
     message.sentTimestamp = [NSDate millisecondTimestamp];
     message.text = text;
     message.quote = [SNQuote from:self.inputToolbar.quotedReply];
-    TSThread *thread = self.thread;
-    TSOutgoingMessage *tsMessage = [TSOutgoingMessage from:message associatedWith:thread];
-    [self.conversationViewModel appendUnsavedOutgoingTextMessage:tsMessage];
+    OWSLinkPreviewDraft *linkPreviewDraft = self.inputToolbar.linkPreviewDraft;
     [LKStorage writeWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
-        [tsMessage saveWithTransaction:transaction];
-    }];
-    [LKStorage writeWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
-        [SNMessageSender send:message withAttachments:@[] inThread:thread usingTransaction:transaction];
-        [thread setDraft:@"" transaction:transaction];
+        message.linkPreview = [SNLinkPreview from:linkPreviewDraft using:transaction];
+    } completion:^{
+        dispatch_async(dispatch_get_main_queue(), ^{
+            TSThread *thread = self.thread;
+            TSOutgoingMessage *tsMessage = [TSOutgoingMessage from:message associatedWith:thread];
+            [self.conversationViewModel appendUnsavedOutgoingTextMessage:tsMessage];
+            [LKStorage writeWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+                [tsMessage saveWithTransaction:transaction];
+            }];
+            [LKStorage writeWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+                [SNMessageSender send:message withAttachments:@[] inThread:thread usingTransaction:transaction];
+                [thread setDraft:@"" transaction:transaction];
+            }];
+            [self messageWasSent:tsMessage];
+            [self.inputToolbar clearTextMessageAnimated:YES];
+            [self resetMentions];
+            dispatch_async(dispatch_get_main_queue(), ^{
+                [[weakSelf inputToolbar] toggleDefaultKeyboard];
+            });
+        });
     }];
-    [self messageWasSent:tsMessage];
-    [self.inputToolbar clearTextMessageAnimated:YES];
-    [self resetMentions];
-    dispatch_async(dispatch_get_main_queue(), ^{
-        [[weakSelf inputToolbar] toggleDefaultKeyboard];
-    });
 }
 
 - (void)voiceMemoGestureDidStart

SessionMessagingKit/Database/Storage+Messaging.swift

@@ -31,11 +31,11 @@ extension Storage {
     }
 
     /// Returns the ID of the `TSIncomingMessage` that was constructed.
-    public func persist(_ message: VisibleMessage, withQuotedMessage quotedMessage: TSQuotedMessage?, groupPublicKey: String?, using transaction: Any) -> String? {
+    public func persist(_ message: VisibleMessage, quotedMessage: TSQuotedMessage?, linkPreview: OWSLinkPreview?, groupPublicKey: String?, using transaction: Any) -> String? {
         let transaction = transaction as! YapDatabaseReadWriteTransaction
         guard let threadID = getOrCreateThread(for: message.sender!, groupPublicKey: groupPublicKey, using: transaction),
             let thread = TSThread.fetch(uniqueId: threadID, transaction: transaction) else { return nil }
-        let message = TSIncomingMessage.from(message, withQuotedMessage: quotedMessage, associatedWith: thread)
+        let message = TSIncomingMessage.from(message, quotedMessage: quotedMessage, linkPreview: linkPreview, associatedWith: thread)
         message.save(with: transaction)
         DispatchQueue.main.async { message.touch() } // FIXME: Hack for a thread updating issue
         return message.uniqueId!

SessionMessagingKit/Messages/Signal/TSIncomingMessage+Conversion.swift

@@ -1,7 +1,7 @@
 
 public extension TSIncomingMessage {
 
-    static func from(_ visibleMessage: VisibleMessage, withQuotedMessage quotedMessage: TSQuotedMessage?, associatedWith thread: TSThread) -> TSIncomingMessage {
+    static func from(_ visibleMessage: VisibleMessage, quotedMessage: TSQuotedMessage?, linkPreview: OWSLinkPreview?, associatedWith thread: TSThread) -> TSIncomingMessage {
         let sender = visibleMessage.sender!
         var expiration: UInt32 = 0
         Storage.read { transaction in
@@ -16,7 +16,7 @@ public extension TSIncomingMessage {
             attachmentIds: visibleMessage.attachmentIDs,
             expiresInSeconds: expiration,
             quotedMessage: quotedMessage,
-            linkPreview: OWSLinkPreview.from(visibleMessage.linkPreview),
+            linkPreview: linkPreview,
             serverTimestamp: nil,
             wasReceivedByUD: true
         )

SessionMessagingKit/Messages/Visible Messages/VisibleMessage+LinkPreview.swift

@@ -6,37 +6,49 @@ public extension VisibleMessage {
     class LinkPreview : NSObject, NSCoding {
         public var title: String?
         public var url: String?
+        public var attachmentID: String?
 
-        public var isValid: Bool { title != nil && url != nil } 
+        public var isValid: Bool { title != nil && url != nil && attachmentID != nil }
 
-        internal init(title: String?, url: String) {
+        internal init(title: String?, url: String, attachmentID: String?) {
             self.title = title
             self.url = url
+            self.attachmentID = attachmentID
         }
 
         public required init?(coder: NSCoder) {
             if let title = coder.decodeObject(forKey: "title") as! String? { self.title = title }
             if let url = coder.decodeObject(forKey: "urlString") as! String? { self.url = url }
+            if let attachmentID = coder.decodeObject(forKey: "attachmentID") as! String? { self.attachmentID = attachmentID }
         }
 
         public func encode(with coder: NSCoder) {
             coder.encode(title, forKey: "title")
             coder.encode(url, forKey: "urlString")
+            coder.encode(attachmentID, forKey: "attachmentID")
         }
 
         public static func fromProto(_ proto: SNProtoDataMessagePreview) -> LinkPreview? {
             let title = proto.title
             let url = proto.url
-            return LinkPreview(title: title, url: url)
+            return LinkPreview(title: title, url: url, attachmentID: nil)
         }
 
         public func toProto() -> SNProtoDataMessagePreview? {
+            preconditionFailure("Use toProto(using:) instead.")
+        }
+
+        public func toProto(using transaction: YapDatabaseReadWriteTransaction) -> SNProtoDataMessagePreview? {
             guard let url = url else {
                 SNLog("Couldn't construct link preview proto from: \(self).")
                 return nil
             }
             let linkPreviewProto = SNProtoDataMessagePreview.builder(url: url)
             if let title = title { linkPreviewProto.setTitle(title) }
+            if let attachmentID = attachmentID, let stream = TSAttachmentStream.fetch(uniqueId: attachmentID, transaction: transaction),
+                let attachmentProto = stream.buildProto() {
+                linkPreviewProto.setImage(attachmentProto)
+            }
             do {
                 return try linkPreviewProto.build()
             } catch {

SessionMessagingKit/Messages/Visible Messages/VisibleMessage.swift

@@ -60,17 +60,27 @@ public final class VisibleMessage : Message {
     
     public func toProto(using transaction: YapDatabaseReadWriteTransaction) -> SNProtoContent? {
         let proto = SNProtoContent.builder()
+        var attachmentIDs = self.attachmentIDs
         let dataMessage: SNProtoDataMessage.SNProtoDataMessageBuilder
+        // Profile
         if let profile = profile, let profileProto = profile.toProto() {
             dataMessage = profileProto.asBuilder()
         } else {
             dataMessage = SNProtoDataMessage.builder()
         }
+        // Text
         if let text = text { dataMessage.setBody(text) }
-        var attachmentIDs = self.attachmentIDs
+        // Quote
         if let quotedAttachmentID = quote?.attachmentID, let index = attachmentIDs.firstIndex(of: quotedAttachmentID) {
             attachmentIDs.remove(at: index)
         }
+        if let quote = quote, let quoteProto = quote.toProto(using: transaction) { dataMessage.setQuote(quoteProto) }
+        // Link preview
+        if let linkPreviewAttachmentID = linkPreview?.attachmentID, let index = attachmentIDs.firstIndex(of: linkPreviewAttachmentID) {
+            attachmentIDs.remove(at: index)
+        }
+        if let linkPreview = linkPreview, let linkPreviewProto = linkPreview.toProto(using: transaction) { dataMessage.setPreview([ linkPreviewProto ]) }
+        // Attachments
         let attachments = attachmentIDs.compactMap { TSAttachmentStream.fetch(uniqueId: $0, transaction: transaction) }
         if !attachments.allSatisfy({ $0.isUploaded }) {
             #if DEBUG
@@ -79,9 +89,8 @@ public final class VisibleMessage : Message {
         }
         let attachmentProtos = attachments.compactMap { $0.buildProto() }
         dataMessage.setAttachments(attachmentProtos)
-        if let quote = quote, let quoteProto = quote.toProto(using: transaction) { dataMessage.setQuote(quoteProto) }
-        if let linkPreview = linkPreview, let linkPreviewProto = linkPreview.toProto() { dataMessage.setPreview([ linkPreviewProto ]) }
         // TODO: Contact
+        // Build
         do {
             proto.setDataMessage(try dataMessage.build())
             return try proto.build()

SessionMessagingKit/Sending & Receiving/Link Previews/OWSLinkPreview+Conversion.swift

@@ -2,6 +2,21 @@
 extension OWSLinkPreview {
     
     public static func from(_ linkPreview: VisibleMessage.LinkPreview?) -> OWSLinkPreview? {
-        return nil // TODO: Implement
+        guard let linkPreview = linkPreview else { return nil }
+        return OWSLinkPreview(urlString: linkPreview.url!, title: linkPreview.title, imageAttachmentId: linkPreview.attachmentID)
+    }
+}
+
+extension VisibleMessage.LinkPreview {
+
+    @objc(from:using:)
+    public static func from(_ linkPreview: OWSLinkPreviewDraft?, using transaction: YapDatabaseReadWriteTransaction) -> VisibleMessage.LinkPreview? {
+        guard let linkPreview = linkPreview else { return nil }
+        do {
+            let linkPreview = try OWSLinkPreview.buildValidatedLinkPreview(fromInfo: linkPreview, transaction: transaction)
+            return VisibleMessage.LinkPreview(title: linkPreview.title, url: linkPreview.urlString!, attachmentID: linkPreview.imageAttachmentId)
+        } catch {
+            return nil
+        }
     }
 }

SessionMessagingKit/Sending & Receiving/MessageReceiver+Handling.swift

@@ -167,8 +167,17 @@ extension MessageReceiver {
                 attachmentIDs.append(id)
             }
         }
+        // Parse link preview if needed
+        var owsLinkPreview: OWSLinkPreview?
+        if message.linkPreview != nil && proto.dataMessage?.preview.isEmpty == false {
+            owsLinkPreview = try? OWSLinkPreview.buildValidatedLinkPreview(dataMessage: proto.dataMessage!, body: message.text, transaction: transaction)
+            if let id = owsLinkPreview?.imageAttachmentId {
+                attachmentIDs.append(id)
+            }
+        }
         // Persist the message
-        guard let tsIncomingMessageID = storage.persist(message, withQuotedMessage: tsQuotedMessage, groupPublicKey: message.groupPublicKey, using: transaction) else { throw Error.noThread }
+        guard let tsIncomingMessageID = storage.persist(message, quotedMessage: tsQuotedMessage, linkPreview: owsLinkPreview,
+            groupPublicKey: message.groupPublicKey, using: transaction) else { throw Error.noThread }
         message.threadID = threadID
         // Start attachment downloads if needed
         storage.withAsync({ transaction in

SessionMessagingKit/Storage.swift

@@ -76,7 +76,7 @@ public protocol SessionMessagingKitStorageProtocol {
     /// Returns the ID of the thread.
     func getOrCreateThread(for publicKey: String, groupPublicKey: String?, using transaction: Any) -> String?
     /// Returns the ID of the `TSIncomingMessage` that was constructed.
-    func persist(_ message: VisibleMessage, withQuotedMessage quotedMessage: TSQuotedMessage?, groupPublicKey: String?, using transaction: Any) -> String?
+    func persist(_ message: VisibleMessage, quotedMessage: TSQuotedMessage?, linkPreview: OWSLinkPreview?, groupPublicKey: String?, using transaction: Any) -> String?
     /// Returns the IDs of the saved attachments.
     func persist(_ attachments: [VisibleMessage.Attachment], using transaction: Any) -> [String]
     /// Also touches the associated message.

SignalUtilitiesKit/Messaging/Sending & Receiving/MessageSender+Handling.swift

@@ -21,12 +21,15 @@ extension MessageSender : SharedSenderKeysDelegate {
             stream.save(with: transaction)
         }
         tsMessage.quotedMessage?.createThumbnailAttachmentsIfNecessary(with: transaction)
-        if let linkPreviewAttachmentID = tsMessage.linkPreview?.imageAttachmentId,
-            let stream = TSAttachment.fetch(uniqueId: linkPreviewAttachmentID, transaction: transaction) as? TSAttachmentStream {
+        var linkPreviewAttachmentID: String?
+        if let id = tsMessage.linkPreview?.imageAttachmentId,
+            let stream = TSAttachment.fetch(uniqueId: id, transaction: transaction) as? TSAttachmentStream {
+            linkPreviewAttachmentID = id
             streams.append(stream)
         }
         message.attachmentIDs = streams.map { $0.uniqueId! }
         tsMessage.attachmentIds.addObjects(from: message.attachmentIDs)
+        if let id = linkPreviewAttachmentID { tsMessage.attachmentIds.remove(id) }
         tsMessage.save(with: transaction)
     }