Merge pull request #904 from RyanRory/fix-link-preview-image

Fix link preview

Session/Conversations/ConversationVC+Interaction.swift

@@ -532,16 +532,34 @@ extension ConversationVC:
                     let insertedInteraction: Interaction = try optimisticData.interaction.inserted(db)
                     self?.viewModel.associate(optimisticMessageId: optimisticData.id, to: insertedInteraction.id)
                     
-                    // If there is a LinkPreview and it doesn't match an existing one then add it now
-                    if
-                        let linkPreviewDraft: LinkPreviewDraft = optimisticData.linkPreviewDraft,
-                        (try? insertedInteraction.linkPreview.isEmpty(db)) == true
-                    {
-                        try LinkPreview(
-                            url: linkPreviewDraft.urlString,
-                            title: linkPreviewDraft.title,
-                            attachmentId: try optimisticData.linkPreviewAttachment?.inserted(db).id
-                        ).insert(db)
+                    // If there is a LinkPreview draft then check the state of any existing link previews and
+                    // insert a new one if needed
+                    if let linkPreviewDraft: LinkPreviewDraft = optimisticData.linkPreviewDraft {
+                        let invalidLinkPreviewAttachmentStates: [Attachment.State] = [
+                            .failedDownload, .pendingDownload, .downloading, .failedUpload, .invalid
+                        ]
+                        let linkPreviewAttachmentId: String? = try? insertedInteraction.linkPreview
+                            .select(.attachmentId)
+                            .asRequest(of: String.self)
+                            .fetchOne(db)
+                        let linkPreviewAttachmentState: Attachment.State = linkPreviewAttachmentId
+                            .map {
+                                try? Attachment
+                                    .filter(id: $0)
+                                    .select(.state)
+                                    .asRequest(of: Attachment.State.self)
+                                    .fetchOne(db)
+                            }
+                            .defaulting(to: .invalid)
+                        
+                        // If we don't have a "valid" existing link preview then upsert a new one
+                        if invalidLinkPreviewAttachmentStates.contains(linkPreviewAttachmentState) {
+                            try LinkPreview(
+                                url: linkPreviewDraft.urlString,
+                                title: linkPreviewDraft.title,
+                                attachmentId: try optimisticData.linkPreviewAttachment?.inserted(db).id
+                            ).save(db)
+                        }
                     }
                     
                     // If there is a Quote the insert it now

Session/Conversations/ConversationViewModel.swift

@@ -265,6 +265,24 @@ public class ConversationViewModel: OWSAudioPlayerDelegate {
                         .allCases
                         .filter { $0 != .wasRead }
                 ),
+                PagedData.ObservedChanges(
+                    table: Attachment.self,
+                    columns: [.state],
+                    joinToPagedType: {
+                        let interaction: TypedTableAlias<Interaction> = TypedTableAlias()
+                        let linkPreview: TypedTableAlias<LinkPreview> = TypedTableAlias()
+                        let linkPreviewAttachment: TypedTableAlias<Attachment> = TypedTableAlias()
+                        
+                        return SQL("""
+                               LEFT JOIN \(LinkPreview.self) ON (
+                                   \(linkPreview[.url]) = \(interaction[.linkPreviewUrl]) AND
+                                   \(Interaction.linkPreviewFilterLiteral())
+                               )
+                               LEFT JOIN \(linkPreviewAttachment) ON \(linkPreviewAttachment[.id]) = \(linkPreview[.attachmentId])
+                            """
+                        )
+                    }()
+                ),
                 PagedData.ObservedChanges(
                     table: Contact.self,
                     columns: [.isTrusted],

Session/Conversations/Message Cells/VisibleMessageCell.swift

@@ -467,7 +467,6 @@ final class VisibleMessageCell: MessageCell, TappableLabelDelegate {
             subview.removeFromSuperview()
         }
         albumView = nil
-        albumView = nil
         bodyTappableLabel = nil
         
         // Handle the deleted state first (it's much simpler than the others)

SessionMessagingKit/Database/Models/LinkPreview.swift

@@ -77,7 +77,7 @@ public struct LinkPreview: Codable, Equatable, Hashable, FetchableRecord, Persis
 // MARK: - Protobuf
 
 public extension LinkPreview {
-    init?(_ db: Database, proto: SNProtoDataMessage, body: String?, sentTimestampMs: TimeInterval) throws {
+    init?(_ db: Database, proto: SNProtoDataMessage, sentTimestampMs: TimeInterval) throws {
         guard let previewProto = proto.preview.first else { throw LinkPreviewError.noPreview }
         guard URL(string: previewProto.url) != nil else { throw LinkPreviewError.invalidInput }
         guard LinkPreview.isValidLinkUrl(previewProto.url) else { throw LinkPreviewError.invalidInput }
@@ -86,9 +86,7 @@ public extension LinkPreview {
         let timestamp: TimeInterval = LinkPreview.timestampFor(sentTimestampMs: sentTimestampMs)
         let maybeLinkPreview: LinkPreview? = try? LinkPreview
             .filter(LinkPreview.Columns.url == previewProto.url)
-            .filter(LinkPreview.Columns.timestamp == LinkPreview.timestampFor(
-                sentTimestampMs: Double(proto.timestamp)
-            ))
+            .filter(LinkPreview.Columns.timestamp == timestamp)
             .fetchOne(db)
         
         if let linkPreview: LinkPreview = maybeLinkPreview {

SessionMessagingKit/Sending & Receiving/Message Handling/MessageReceiver+VisibleMessages.swift

@@ -276,7 +276,6 @@ extension MessageReceiver {
         let linkPreview: LinkPreview? = try? LinkPreview(
             db,
             proto: dataMessage,
-            body: message.text,
             sentTimestampMs: (messageSentTimestamp * 1000)
         )?.saved(db)