Got paging working on the conversation screen

Fixed a couple of issues where attachment messages would flicker due to thread changing
Fixed a couple of issues with page loading
Connected the global search result select back up

Session.xcodeproj/project.pbxproj

@@ -685,6 +685,7 @@
 		FD848B87283B844B000E298B /* MessageCellViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD848B86283B844B000E298B /* MessageCellViewModel.swift */; };
 		FD848B8B283DC509000E298B /* PagedDatabaseObserver.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD848B8A283DC509000E298B /* PagedDatabaseObserver.swift */; };
 		FD848B8D283E0B26000E298B /* MessageInputTypes.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD848B8C283E0B26000E298B /* MessageInputTypes.swift */; };
+		FD848B8F283EF2A8000E298B /* UIScrollView+Utilities.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD848B8E283EF2A8000E298B /* UIScrollView+Utilities.swift */; };
 		FD859F0027C4691300510D0C /* MockDataGenerator.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD859EFF27C4691300510D0C /* MockDataGenerator.swift */; };
 		FD88BAD927A7439C00BBC442 /* MessageRequestsCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD88BAD827A7439C00BBC442 /* MessageRequestsCell.swift */; };
 		FD88BADB27A750F200BBC442 /* MessageRequestsMigration.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD88BADA27A750F200BBC442 /* MessageRequestsMigration.swift */; };
@@ -1661,6 +1662,7 @@
 		FD848B86283B844B000E298B /* MessageCellViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageCellViewModel.swift; sourceTree = "<group>"; };
 		FD848B8A283DC509000E298B /* PagedDatabaseObserver.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PagedDatabaseObserver.swift; sourceTree = "<group>"; };
 		FD848B8C283E0B26000E298B /* MessageInputTypes.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageInputTypes.swift; sourceTree = "<group>"; };
+		FD848B8E283EF2A8000E298B /* UIScrollView+Utilities.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "UIScrollView+Utilities.swift"; sourceTree = "<group>"; };
 		FD859EFF27C4691300510D0C /* MockDataGenerator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MockDataGenerator.swift; sourceTree = "<group>"; };
 		FD88BAD827A7439C00BBC442 /* MessageRequestsCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageRequestsCell.swift; sourceTree = "<group>"; };
 		FD88BADA27A750F200BBC442 /* MessageRequestsMigration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageRequestsMigration.swift; sourceTree = "<group>"; };
@@ -1935,6 +1937,7 @@
 				B8783E9D23EB948D00404FB8 /* UILabel+Interaction.swift */,
 				B83F2B87240CB75A000A54AB /* UIImage+Scaling.swift */,
 				FD1C98E3282E3C5B00B76F9E /* UINavigationBar+Utilities.swift */,
+				FD848B8E283EF2A8000E298B /* UIScrollView+Utilities.swift */,
 				C31A6C59247F214E001123EF /* UIView+Glow.swift */,
 				C3548F0724456AB6009433A8 /* UIView+Wrapping.swift */,
 				FD859EFF27C4691300510D0C /* MockDataGenerator.swift */,
@@ -4705,6 +4708,7 @@
 				C3E5C2FA251DBABB0040DFFC /* EditClosedGroupVC.swift in Sources */,
 				B8783E9E23EB948D00404FB8 /* UILabel+Interaction.swift in Sources */,
 				B893063F2383961A005EAA8E /* ScanQRCodeWrapperVC.swift in Sources */,
+				FD848B8F283EF2A8000E298B /* UIScrollView+Utilities.swift in Sources */,
 				B879D449247E1BE300DB3608 /* PathVC.swift in Sources */,
 				454A84042059C787008B8C75 /* MediaTileViewController.swift in Sources */,
 				34D1F0871F8678AA0066283D /* ConversationViewItem.m in Sources */,

Session/Conversations/ConversationVC+Interaction.swift

@@ -632,8 +632,12 @@ extension ConversationVC:
         // Show the context menu if applicable
         guard
             let keyWindow: UIWindow = UIApplication.shared.keyWindow,
-            let index = viewModel.interactionData.firstIndex(of: cellViewModel),
-            let cell = tableView.cellForRow(at: IndexPath(row: index, section: 0)) as? VisibleMessageCell,
+            let sectionIndex: Int = self.viewModel.interactionData
+                .firstIndex(where: { $0.model == .messages }),
+            let index = self.viewModel.interactionData[sectionIndex]
+                .elements
+                .firstIndex(of: cellViewModel),
+            let cell = tableView.cellForRow(at: IndexPath(row: index, section: sectionIndex)) as? VisibleMessageCell,
             let snapshot = cell.bubbleView.snapshotView(afterScreenUpdates: false),
             contextMenuWindow == nil,
             let actions: [ContextMenuVC.Action] = ContextMenuVC.actions(
@@ -693,8 +697,12 @@ extension ConversationVC:
             
             case .mediaMessage:
                 guard
-                    let index = self.viewModel.interactionData.firstIndex(where: { $0.id == cellViewModel.id }),
-                    let cell = tableView.cellForRow(at: IndexPath(row: index, section: 0)) as? VisibleMessageCell,
+                    let sectionIndex: Int = self.viewModel.interactionData
+                        .firstIndex(where: { $0.model == .messages }),
+                    let messageIndex: Int = self.viewModel.interactionData[sectionIndex]
+                        .elements
+                        .firstIndex(where: { $0.id == cellViewModel.id }),
+                    let cell = tableView.cellForRow(at: IndexPath(row: messageIndex, section: sectionIndex)) as? VisibleMessageCell,
                     let albumView: MediaAlbumView = cell.albumView
                 else { return }
                 

Session/Conversations/ConversationVC.swift

@@ -937,12 +937,20 @@ final class ConversationVC: BaseVC, OWSConversationSettingsViewDelegate, Convers
     }
 
     func scrollToBottom(isAnimated: Bool) {
-        guard !isUserScrolling && !viewModel.interactionData.isEmpty else { return }
+        guard
+            !isUserScrolling,
+            let messagesSectionIndex: Int = self.viewModel.interactionData
+                .firstIndex(where: { $0.model == .messages }),
+            !self.viewModel.interactionData[messagesSectionIndex]
+                .elements
+                .isEmpty
+        else { return }
         
         tableView.scrollToRow(
             at: IndexPath(
-                row: viewModel.interactionData.count - 1,
-                section: 0),
+                row: viewModel.interactionData[messagesSectionIndex].elements.count - 1,
+                section: messagesSectionIndex
+            ),
             at: .bottom,
             animated: isAnimated
         )
@@ -959,7 +967,6 @@ final class ConversationVC: BaseVC, OWSConversationSettingsViewDelegate, Convers
     func scrollViewDidScroll(_ scrollView: UIScrollView) {
         scrollButton.alpha = getScrollButtonOpacity()
         unreadCountView.alpha = scrollButton.alpha
-        autoLoadMoreIfNeeded()
     }
 
     func updateUnreadCountView(unreadCount: UInt?) {
@@ -970,14 +977,6 @@ final class ConversationVC: BaseVC, OWSConversationSettingsViewDelegate, Convers
         unreadCountView.isHidden = (unreadCount == 0)
     }
 
-    func autoLoadMoreIfNeeded() {
-        let isMainAppAndActive = CurrentAppContext().isMainAppAndActive
-        guard isMainAppAndActive && didFinishInitialLayout && viewModel.canLoadMoreItems() && !isLoadingMore
-            && messagesTableView.contentOffset.y < ConversationVC.loadMoreThreshold else { return }
-        isLoadingMore = true
-        viewModel.loadAnotherPageOfMessages()
-    }
-
     func getScrollButtonOpacity() -> CGFloat {
         let contentOffsetY = tableView.contentOffset.y
         let x = (lastPageTop - ConversationVC.bottomInset - contentOffsetY).clamp(0, .greatestFiniteMagnitude)
@@ -1078,5 +1077,28 @@ final class ConversationVC: BaseVC, OWSConversationSettingsViewDelegate, Convers
         isAnimated: Bool = true,
         highlighted: Bool = false
     ) {
+        // Ensure the interaction is loaded
+        self.viewModel.pagedDataObserver?.load(.untilInclusive(id: interactionId, padding: 0))
+        
+        guard
+            let messageSectionIndex: Int = self.viewModel.interactionData
+                .firstIndex(where: { $0.model == .messages }),
+            let targetMessageIndex = self.viewModel.interactionData[messageSectionIndex]
+                .elements
+                .firstIndex(where: { $0.id == interactionId })
+        else { return }
+
+        tableView.scrollToRow(
+            at: IndexPath(
+                row: targetMessageIndex,
+                section: messageSectionIndex
+            ),
+            at: position,
+            animated: isAnimated
+        )
+
+        if highlighted {
+            focusedMessageId = interactionId
+        }
     }
 }

Session/Conversations/ConversationViewModel.swift

@@ -7,6 +7,10 @@ import SessionMessagingKit
 import SessionUtilitiesKit
 
 public class ConversationViewModel: OWSAudioPlayerDelegate {
+    public typealias SectionModel = ArraySection<Section, MessageCell.ViewModel>
+    
+    // MARK: - Action
+    
     public enum Action {
         case none
         case compose
@@ -15,6 +19,16 @@ public class ConversationViewModel: OWSAudioPlayerDelegate {
     }
     
     public static let pageSize: Int = 50
+    // MARK: - Section
+    
+    public enum Section: Differentiable, Equatable, Comparable, Hashable {
+        case loadOlder
+        case messages
+        case loadNewer
+    }
+    
+    // MARK: - Variables
+    
     
     // MARK: - Initialization
     
@@ -34,58 +48,52 @@ public class ConversationViewModel: OWSAudioPlayerDelegate {
         
         self.threadId = threadId
         self.threadData = threadData
-        self.focusedInteractionId = focusedInteractionId    // TODO: This
+        self.focusedInteractionId = focusedInteractionId
         self.pagedDataObserver = nil
-        var hasSavedIntialUpdate: Bool = false
-        self.pagedDataObserver = PagedDatabaseObserver(
-            pagedTable: Interaction.self,
-            pageSize: ConversationViewModel.pageSize,
-            idColumn: .id,
-            initialFocusedId: nil,
-            observedChanges: [
-                PagedData.ObservedChanges(
-                    table: Interaction.self,
-                    columns: Interaction.Columns
-                        .allCases
-                        .filter { $0 != .wasRead }
-                )
-            ],
-            filterSQL: MessageCell.ViewModel.filterSQL(threadId: threadId),
-            orderSQL: MessageCell.ViewModel.orderSQL,
-            dataQuery: MessageCell.ViewModel.baseQuery(
+        
+        DispatchQueue.global(qos: .default).async { [weak self] in
+            self?.pagedDataObserver = PagedDatabaseObserver(
+                pagedTable: Interaction.self,
+                pageSize: ConversationViewModel.pageSize,
+                idColumn: .id,
+                initialFocusedId: focusedInteractionId,
+                observedChanges: [
+                    PagedData.ObservedChanges(
+                        table: Interaction.self,
+                        columns: Interaction.Columns
+                            .allCases
+                            .filter { $0 != .wasRead }
+                    )
+                ],
+                filterSQL: MessageCell.ViewModel.filterSQL(threadId: threadId),
                 orderSQL: MessageCell.ViewModel.orderSQL,
-                baseFilterSQL: MessageCell.ViewModel.filterSQL(threadId: threadId)
-            ),
-            associatedRecords: [
-                AssociatedRecord<MessageCell.AttachmentInteractionInfo, MessageCell.ViewModel>(
-                    trackedAgainst: Attachment.self,
-                    observedChanges: [
-                        PagedData.ObservedChanges(
-                            table: Attachment.self,
-                            columns: [.state]
-                        )
-                    ],
-                    dataQuery: MessageCell.AttachmentInteractionInfo.baseQuery,
-                    joinToPagedType: MessageCell.AttachmentInteractionInfo.joinToViewModelQuerySQL,
-                    associateData: MessageCell.AttachmentInteractionInfo.createAssociateDataClosure()
-                )
-            ],
-            onChangeUnsorted: { [weak self] updatedData, updatedPageInfo in
-                guard let updatedInteractionData: [MessageCell.ViewModel] = self?.process(data: updatedData, for: updatedPageInfo) else {
-                    return
-                }
-                
-                // If we haven't stored the data for the initial fetch then do so now (no need
-                // to call 'onInteractionsChange' in this case as it will always be null)
-                guard hasSavedIntialUpdate else {
-                    self?.updateInteractionData(updatedInteractionData)
-                    hasSavedIntialUpdate = true
-                    return
+                dataQuery: MessageCell.ViewModel.baseQuery(
+                    orderSQL: MessageCell.ViewModel.orderSQL,
+                    baseFilterSQL: MessageCell.ViewModel.filterSQL(threadId: threadId)
+                ),
+                associatedRecords: [
+                    AssociatedRecord<MessageCell.AttachmentInteractionInfo, MessageCell.ViewModel>(
+                        trackedAgainst: Attachment.self,
+                        observedChanges: [
+                            PagedData.ObservedChanges(
+                                table: Attachment.self,
+                                columns: [.state]
+                            )
+                        ],
+                        dataQuery: MessageCell.AttachmentInteractionInfo.baseQuery,
+                        joinToPagedType: MessageCell.AttachmentInteractionInfo.joinToViewModelQuerySQL,
+                        associateData: MessageCell.AttachmentInteractionInfo.createAssociateDataClosure()
+                    )
+                ],
+                onChangeUnsorted: { [weak self] updatedData, updatedPageInfo in
+                    guard let updatedInteractionData: [SectionModel] = self?.process(data: updatedData, for: updatedPageInfo) else {
+                        return
+                    }
+                    
+                    self?.onInteractionChange?(updatedInteractionData)
                 }
-                
-                self?.onInteractionChange?(updatedInteractionData)
-            }
-        )
+            )
+        }
     }
     
     // MARK: - Variables
@@ -130,29 +138,44 @@ public class ConversationViewModel: OWSAudioPlayerDelegate {
     
     // MARK: - Interaction Data
     
-    public private(set) var interactionData: [MessageCell.ViewModel] = []
+    public private(set) var interactionData: [SectionModel] = []
     public private(set) var pagedDataObserver: PagedDatabaseObserver<Interaction, MessageCell.ViewModel>?
-    public var onInteractionChange: (([MessageCell.ViewModel]) -> ())?
+    public var onInteractionChange: (([SectionModel]) -> ())?
     
-    private func process(data: [MessageCell.ViewModel], for pageInfo: PagedData.PageInfo) -> [MessageCell.ViewModel] {
+    private func process(data: [MessageCell.ViewModel], for pageInfo: PagedData.PageInfo) -> [SectionModel] {
         let sortedData: [MessageCell.ViewModel] = data
             .sorted { lhs, rhs -> Bool in lhs.timestampMs < rhs.timestampMs }
         
-        return sortedData
-            .enumerated()
-            .map { index, cellViewModel -> MessageCell.ViewModel in
-                cellViewModel.withClusteringChanges(
-                    prevModel: (index > 0 ? sortedData[index - 1] : nil),
-                    nextModel: (index < (sortedData.count - 2) ? sortedData[index + 1] : nil),
-                    isLast: (
-                        index == (sortedData.count - 1) &&
-                        pageInfo.currentCount == pageInfo.totalCount
-                    )
+        return [
+            (!data.isEmpty && (pageInfo.pageOffset + pageInfo.currentCount) < pageInfo.totalCount ?
+                [SectionModel(section: .loadOlder)] :
+                []
+            ),
+            [
+                SectionModel(
+                    section: .messages,
+                    elements: sortedData
+                        .enumerated()
+                        .map { index, cellViewModel -> MessageCell.ViewModel in
+                            cellViewModel.withClusteringChanges(
+                                prevModel: (index > 0 ? sortedData[index - 1] : nil),
+                                nextModel: (index < (sortedData.count - 2) ? sortedData[index + 1] : nil),
+                                isLast: (
+                                    index == (sortedData.count - 1) &&
+                                    pageInfo.currentCount == pageInfo.totalCount
+                                )
+                            )
+                        }
                 )
-            }
+            ],
+            (data.isEmpty && pageInfo.pageOffset > 0 ?
+                [SectionModel(section: .loadNewer)] :
+                []
+            )
+        ].flatMap { $0 }
     }
     
-    public func updateInteractionData(_ updatedData: [MessageCell.ViewModel]) {
+    public func updateInteractionData(_ updatedData: [SectionModel]) {
         self.interactionData = updatedData
     }
     
@@ -288,7 +311,13 @@ public class ConversationViewModel: OWSAudioPlayerDelegate {
     }
     
     public func markAllAsRead() {
-        guard let lastInteractionId: Int64 = self.interactionData.last?.id else { return }
+        guard
+            let lastInteractionId: Int64 = self.interactionData
+                .first(where: { $0.model == .messages })?
+                .elements
+                .last?
+                .id
+        else { return }
         
         GRDBStorage.shared.write { db in
             try Interaction.markAsRead(
@@ -487,12 +516,15 @@ public class ConversationViewModel: OWSAudioPlayerDelegate {
         
         // If the next interaction is another voice message then autoplay it
         guard
-            let currentIndex: Int = self.interactionData.firstIndex(where: { $0.id == interactionId }),
-            currentIndex < (self.interactionData.count - 1),
-            self.interactionData[currentIndex + 1].cellType == .audio
+            let messageSection: SectionModel = self.interactionData
+                .first(where: { $0.model == .messages }),
+            let currentIndex: Int = messageSection.elements
+                .firstIndex(where: { $0.id == interactionId }),
+            currentIndex < (messageSection.elements.count - 1),
+            messageSection.elements[currentIndex + 1].cellType == .audio
         else { return }
         
-        let nextItem: MessageCell.ViewModel = self.interactionData[currentIndex + 1]
+        let nextItem: MessageCell.ViewModel = messageSection.elements[currentIndex + 1]
         playOrPauseAudio(for: nextItem)
     }
     

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

@@ -173,7 +173,7 @@ public class MediaView: UIView {
                         owsFailDebug("Media has unexpected type: \(type(of: media))")
                         return
                     }
-                    
+                    // FIXME: Animated images flicker when reloading the cells (even though they are in the cache)
                     animatedImageView.image = image
                 },
                 cacheKey: attachment.id
@@ -365,9 +365,9 @@ public class MediaView: UIView {
         if let media: AnyObject = self.mediaCache.object(forKey: cacheKey as NSString) {
             Logger.verbose("media cache hit")
             
-            guard !Thread.isMainThread else {
+            guard Thread.isMainThread else {
                 DispatchQueue.main.async {
-                    loadMediaBlock(loadCompletion)
+                    loadCompletion(media)
                 }
                 return
             }

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

@@ -136,10 +136,16 @@ final class QuoteView: UIView {
             attachment.thumbnail(
                 size: .small,
                 success: { image, _ in
-                    DispatchQueue.main.async {
-                        imageView.image = image
-                        imageView.contentMode = .scaleAspectFill
+                    guard Thread.isMainThread else {
+                        DispatchQueue.main.async {
+                            imageView.image = image
+                            imageView.contentMode = .scaleAspectFill
+                        }
+                        return
                     }
+                    
+                    imageView.image = image
+                    imageView.contentMode = .scaleAspectFill
                 },
                 failure: {}
             )

Session/Conversations/Views & Modals/InsetLockableTableView.swift

@@ -2,9 +2,14 @@
 
 import UIKit
 
-/// This custom UITableView allows us to lock the contentOffset to a specific value - it's current used to prevent
-/// the ConversationVC first responder resignation from making the MediaGalleryDetailViewController transition
-/// from looking buggy (ie. the table scrolls down with the resignation during the transition)
+/// This custom UITableView gives us two convenience behaviours:
+///
+/// 1. It allows us to lock the contentOffset to a specific value - it's currently used to prevent the ConversationVC first
+/// responder resignation from making the MediaGalleryDetailViewController transition from looking buggy (ie. the table
+/// scrolls down with the resignation during the transition)
+///
+/// 2. It allows us to provode a callback which gets triggered if a condition closure returns true - it's currently used to prevent
+/// the table view from jumping when inserting new pages at the top of a conversation screen
 public class InsetLockableTableView: UITableView {
     public var lockContentOffset: Bool = false {
         didSet {
@@ -15,6 +20,8 @@ public class InsetLockableTableView: UITableView {
     }
     public var oldOffset: CGPoint = .zero
     public var newOffset: CGPoint = .zero
+    private var afterNextLayoutCondition: ((Int, [Int]) -> Bool)?
+    private var afterNextLayoutCallback: (() -> ())?
     
     public override func layoutSubviews() {
         newOffset = self.contentOffset
@@ -24,12 +31,35 @@ public class InsetLockableTableView: UITableView {
                 x: newOffset.x,
                 y: oldOffset.y
             )
+            
             super.layoutSubviews()
+            
+            self.performNextLayoutCallbackIfPossible()
             return
         }
         
         super.layoutSubviews()
         
-        oldOffset = self.contentOffset
+        self.performNextLayoutCallbackIfPossible()
+        self.oldOffset = self.contentOffset
+    }
+    
+    // MARK: - Function
+    
+    public func afterNextLayout(when condition: @escaping (Int, [Int]) -> Bool, then callback: @escaping () -> ()) {
+        self.afterNextLayoutCondition = condition
+        self.afterNextLayoutCallback = callback
+    }
+    
+    private func performNextLayoutCallbackIfPossible() {
+        let numSections: Int = self.numberOfSections
+        let numRowInSections: [Int] = (0..<numSections)
+            .map { self.numberOfRows(inSection: $0) }
+        
+        guard self.afterNextLayoutCondition?(numSections, numRowInSections) == true else { return }
+        
+        self.afterNextLayoutCallback?()
+        self.afterNextLayoutCondition = nil
+        self.afterNextLayoutCallback = nil
     }
 }

Session/Home/GlobalSearch/EmptySearchResultCell.swift

@@ -26,6 +26,7 @@ class EmptySearchResultCell: UITableViewCell {
         super.init(style: style, reuseIdentifier: reuseIdentifier)
         
         backgroundColor = .clear
+        selectionStyle = .none
         
         contentView.addSubview(messageLabel)
         messageLabel.autoSetDimension(.height, toSize: 150)

Session/Home/GlobalSearch/GlobalSearchViewController.swift

@@ -9,13 +9,35 @@ import SessionUtilitiesKit
 import SignalUtilitiesKit
 
 class GlobalSearchViewController: BaseVC, UITableViewDelegate, UITableViewDataSource {
-    private struct SearchResultSet {
-        let contactsAndGroups: [ConversationCell.ViewModel]
-        let messages: [ConversationCell.ViewModel]
+    fileprivate typealias SectionModel = ArraySection<SearchSection, ConversationCell.ViewModel>
+    
+    // MARK: - SearchSection
+    
+    enum SearchSection: Int, Differentiable {
+        case noResults
+        case contactsAndGroups
+        case messages
     }
     
-    let isRecentSearchResultsEnabled = false
-
+    // MARK: - Variables
+    
+    private lazy var defaultSearchResults: [SectionModel] = {
+        let result: ConversationCell.ViewModel? = GRDBStorage.shared.read { db -> ConversationCell.ViewModel? in
+            try ConversationCell.ViewModel
+                .noteToSelfOnlyQuery(userPublicKey: getUserHexEncodedPublicKey(db))
+                .fetchOne(db)
+        }
+        
+        return [ result.map { ArraySection(model: .contactsAndGroups, elements: [$0]) } ]
+            .compactMap { $0 }
+    }()
+    private lazy var searchResultSet: [SectionModel] = self.defaultSearchResults
+    private var termForCurrentSearchResultSet: String = ""
+    private var lastSearchText: String?
+    private var refreshTimer: Timer?
+    
+    var isLoading = false
+    
     @objc public var searchText = "" {
         didSet {
             AssertIsOnMainThread()
@@ -23,23 +45,6 @@ class GlobalSearchViewController: BaseVC, UITableViewDelegate, UITableViewDataSo
             refreshSearchResults()
         }
     }
-    var defaultSearchResults: HomeScreenSearchResultSet = HomeScreenSearchResultSet.noteToSelfOnly
-    
-    var searchResultSet: [ArraySection<SearchSection, ConversationCell.ViewModel>] = []
-    private var termForCurrentSearchResultSet: String = ""
-    
-    
-    private var lastSearchText: String?
-    var searcher: FullTextSearcher {
-        return FullTextSearcher.shared
-    }
-    var isLoading = false
-
-    enum SearchSection: Int, Differentiable {
-        case noResults
-        case contactsAndGroups
-        case messages
-    }
 
     // MARK: - UI Components
 
@@ -114,8 +119,6 @@ class GlobalSearchViewController: BaseVC, UITableViewDelegate, UITableViewDataSo
 
     // MARK: - Update Search Results
 
-    var refreshTimer: Timer?
-
     private func refreshSearchResults() {
         refreshTimer?.invalidate()
         refreshTimer = WeakTimer.scheduledTimer(timeInterval: 0.1, target: self, userInfo: nil, repeats: false) { [weak self] _ in
@@ -136,49 +139,55 @@ class GlobalSearchViewController: BaseVC, UITableViewDelegate, UITableViewDataSo
 
         lastSearchText = searchText
 
-        GRDBStorage.shared
-            .read { db -> Result<SearchResultSet, Error> in
-                do {
-                    let contactsAndGroupsResults: [ConversationCell.ViewModel] = try ConversationCell.ViewModel
-                        .contactsAndGroupsQuery(
-                            userPublicKey: getUserHexEncodedPublicKey(db),
-                            pattern: try ConversationCell.ViewModel.pattern(db, searchTerm: searchText),
-                            searchTerm: searchText
-                        )
-                        .fetchAll(db)
-                    
-                    let messageResults: [ConversationCell.ViewModel] = try ConversationCell.ViewModel
-                        .messagesQuery(
-                            userPublicKey: getUserHexEncodedPublicKey(db),
-                            pattern: try ConversationCell.ViewModel.pattern(db, searchTerm: searchText)
-                        )
-                        .fetchAll(db)
-                    
-                    return .success(SearchResultSet(
-                        contactsAndGroups: contactsAndGroupsResults,
-                        messages: messageResults
-                    ))
-                }
-                catch {
-                    return .failure(error)
-                }
+        let result: Result<[SectionModel], Error>? = GRDBStorage.shared.read { db -> Result<[SectionModel], Error> in
+            do {
+                let userPublicKey: String = getUserHexEncodedPublicKey(db)
+                
+                let contactsAndGroupsResults: [ConversationCell.ViewModel] = try ConversationCell.ViewModel
+                    .contactsAndGroupsQuery(
+                        userPublicKey: userPublicKey,
+                        pattern: try ConversationCell.ViewModel.pattern(db, searchTerm: searchText),
+                        searchTerm: searchText
+                    )
+                    .fetchAll(db)
+                
+                let messageResults: [ConversationCell.ViewModel] = try ConversationCell.ViewModel
+                    .messagesQuery(
+                        userPublicKey: userPublicKey,
+                        pattern: try ConversationCell.ViewModel.pattern(db, searchTerm: searchText)
+                    )
+                    .fetchAll(db)
+                
+                return .success([
+                    ArraySection(model: .contactsAndGroups, elements: contactsAndGroupsResults),
+                    ArraySection(model: .messages, elements: messageResults)
+                ])
             }
-            .map { [weak self] result in
-                switch result {
-                    case .success(let resultSet):
-                        self?.termForCurrentSearchResultSet = searchText
-                        self?.searchResultSet = [
-                            ArraySection(model: .contactsAndGroups, elements: resultSet.contactsAndGroups),
-                            ArraySection(model: .messages, elements: resultSet.messages)
-                        ]
-                        self?.isLoading = false
-                        self?.reloadTableData()
-                        self?.refreshTimer = nil
-                        
-                        
-                    case .failure: break
-                }
+            catch {
+                return .failure(error)
             }
+        }
+        
+        switch result {
+            case .success(let sections):
+                let hasResults: Bool = (
+                    !searchText.isEmpty &&
+                    (sections.map { $0.elements.count }.reduce(0, +) > 0)
+                )
+                
+                self.termForCurrentSearchResultSet = searchText
+                self.searchResultSet = [
+                    (hasResults ? nil : [ArraySection(model: .noResults, elements: [ConversationCell.ViewModel(unreadCount: 0)])]),
+                    (hasResults ? sections : nil)
+                ]
+                .compactMap { $0 }
+                .flatMap { $0 }
+                self.isLoading = false
+                self.reloadTableData()
+                self.refreshTimer = nil
+                
+            default: break
+        }
     }
 }
 
@@ -218,30 +227,40 @@ extension GlobalSearchViewController {
     public func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
         tableView.deselectRow(at: indexPath, animated: false)
         
-        guard let searchSection = SearchSection(rawValue: indexPath.section) else { return }
+        let section: SectionModel = self.searchResultSet[indexPath.section]
         
-        switch searchSection {
-            case .noResults:
-                SNLog("shouldn't be able to tap 'no results' section")
-                
-            case .contactsAndGroups:
-                break
-                
-            case .messages:
-                break
+        switch section.model {
+            case .noResults: break
+            case .contactsAndGroups, .messages:
+                show(
+                    threadId: section.elements[indexPath.row].threadId,
+                    focusedInteractionId: section.elements[indexPath.row].interactionId
+                )
         }
     }
 
-    private func show(_ thread: TSThread, highlightedMessageID: String?, animated: Bool, isFromRecent: Bool = false) {
-            if let presentedVC = self.presentedViewController {
-                presentedVC.dismiss(animated: false, completion: nil)
+    private func show(threadId: String, focusedInteractionId: Int64? = nil, animated: Bool = true) {
+        guard Thread.isMainThread else {
+            DispatchQueue.main.async { [weak self] in
+                self?.show(threadId: threadId, focusedInteractionId: focusedInteractionId, animated: animated)
             }
-            let conversationVC = ConversationVC(thread: thread, focusedMessageID: highlightedMessageID)
-            var viewControllers = self.navigationController?.viewControllers
-            if isFromRecent, let index = viewControllers?.firstIndex(of: self) { viewControllers?.remove(at: index) }
-            viewControllers?.append(conversationVC)
-            self.navigationController?.setViewControllers(viewControllers!, animated: true)
+            return
+        }
+        
+        guard let conversationVC: ConversationVC = ConversationVC(threadId: threadId, focusedInteractionId: focusedInteractionId) else {
+            return
+        }
+        
+        if let presentedVC = self.presentedViewController {
+            presentedVC.dismiss(animated: false, completion: nil)
         }
+        
+        let viewControllers: [UIViewController] = (self.navigationController?
+            .viewControllers)
+            .defaulting(to: [])
+            .appending(conversationVC)
+        
+        self.navigationController?.setViewControllers(viewControllers, animated: true)
     }
 
     // MARK: - UITableViewDataSource
@@ -249,6 +268,10 @@ extension GlobalSearchViewController {
     public func numberOfSections(in tableView: UITableView) -> Int {
         return self.searchResultSet.count
     }
+    
+    public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
+        return self.searchResultSet[section].elements.count
+    }
 
     public func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
         UIView()
@@ -286,7 +309,8 @@ extension GlobalSearchViewController {
     }
 
     public func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
-        let section: ArraySection<SearchSection, ConversationCell.ViewModel> = self.searchResultSet[section]
+        let section: SectionModel = self.searchResultSet[section]
+        
         switch section.model {
             case .noResults: return nil
             case .contactsAndGroups: return (section.elements.isEmpty ? nil : "SEARCH_SECTION_CONTACTS".localized())
@@ -294,16 +318,12 @@ extension GlobalSearchViewController {
         }
     }
 
-    public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
-        return self.searchResultSet[section].elements.count
-    }
-
     public func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
         return UITableView.automaticDimension
     }
 
     public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
-        let section: ArraySection<SearchSection, ConversationCell.ViewModel> = self.searchResultSet[indexPath.section]
+        let section: SectionModel = self.searchResultSet[indexPath.section]
         
         switch section.model {
             case .noResults:

Session/Media Viewing & Editing/MediaGalleryViewModel.swift

@@ -18,6 +18,8 @@ public class MediaGalleryViewModel {
         case loadNewer
     }
     
+    // MARK: - Variables
+    
     public let threadId: String
     public let threadVariant: SessionThread.Variant
     private var focusedAttachmentId: String?
@@ -30,7 +32,7 @@ public class MediaGalleryViewModel {
     public var interactionIdBefore: [Int64: Int64] { cachedInteractionIdBefore.wrappedValue }
     public var interactionIdAfter: [Int64: Int64] { cachedInteractionIdAfter.wrappedValue }
     public private(set) var albumData: [Int64: [Item]] = [:]
-    public private(set) var pagedDatabaseObserver: PagedDatabaseObserver<Attachment, Item>?
+    public private(set) var pagedDataObserver: PagedDatabaseObserver<Attachment, Item>?
     
     /// This value is the current state of a gallery view
     public private(set) var galleryData: [SectionModel] = []
@@ -48,13 +50,13 @@ public class MediaGalleryViewModel {
         self.threadId = threadId
         self.threadVariant = threadVariant
         self.focusedAttachmentId = focusedAttachmentId
-        self.pagedDatabaseObserver = nil
+        self.pagedDataObserver = nil
         
         guard isPagedData else { return }
      
         var hasSavedIntialUpdate: Bool = false
         let filterSQL: SQL = Item.filterSQL(threadId: threadId)
-        self.pagedDatabaseObserver = PagedDatabaseObserver(
+        self.pagedDataObserver = PagedDatabaseObserver(
             pagedTable: Attachment.self,
             pageSize: pageSize,
             idColumn: .id,
@@ -433,14 +435,6 @@ public class MediaGalleryViewModel {
         }
     }
     
-    public func loadNewerGalleryItems() {
-        self.pagedDatabaseObserver?.load(.pageBefore)
-    }
-    
-    public func loadOlderGalleryItems() {
-        self.pagedDatabaseObserver?.load(.pageAfter)
-    }
-    
     public func updateFocusedItem(attachmentId: String, indexPath: IndexPath) {
         // Note: We need to set both of these as the 'focusedIndexPath' is usually
         // derived and if the data changes it will be regenerated using the

Session/Media Viewing & Editing/MediaTileViewController.swift

@@ -20,6 +20,7 @@ public class MediaTileViewController: UIViewController, UICollectionViewDataSour
     
     private let viewModel: MediaGalleryViewModel
     private var hasLoadedInitialData: Bool = false
+    private var isAutoLoadingNextPage: Bool = false
     private var currentTargetOffset: CGPoint?
     
     var isInBatchSelectMode = false {
@@ -34,7 +35,7 @@ public class MediaTileViewController: UIViewController, UICollectionViewDataSour
 
     init(viewModel: MediaGalleryViewModel) {
         self.viewModel = viewModel
-        GRDBStorage.shared.addObserver(viewModel.pagedDatabaseObserver)
+        GRDBStorage.shared.addObserver(viewModel.pagedDataObserver)
 
         super.init(nibName: nil, bundle: nil)
     }
@@ -212,20 +213,30 @@ public class MediaTileViewController: UIViewController, UICollectionViewDataSour
     }
     
     private func autoLoadNextPageIfNeeded() {
+        guard !self.isAutoLoadingNextPage else { return }
+        
+        self.isAutoLoadingNextPage = true
+        
         DispatchQueue.main.asyncAfter(deadline: .now() + MediaTileViewController.autoLoadNextPageDelay) { [weak self] in
+            self?.isAutoLoadingNextPage = false
+            
+            // Note: We sort the headers as we want to prioritise loading newer pages over older ones
             let sortedVisibleIndexPaths: [IndexPath] = (self?.collectionView
                 .indexPathsForVisibleSupplementaryElements(ofKind: UICollectionView.elementKindSectionHeader))
                 .defaulting(to: [])
                 .sorted()
             
             for headerIndexPath in sortedVisibleIndexPaths {
-                switch self?.viewModel.galleryData[safe: headerIndexPath.section]?.model {
-                    case .loadNewer:
-                        self?.viewModel.loadNewerGalleryItems()
-                        return
-                        
-                    case .loadOlder:
-                        self?.viewModel.loadOlderGalleryItems()
+                let section: MediaGalleryViewModel.SectionModel? = self?.viewModel.galleryData[safe: headerIndexPath.section]
+                
+                switch section?.model {
+                    case .loadNewer, .loadOlder:
+                        // Attachments are loaded in descending order so 'loadOlder' actually corresponds with
+                        // 'pageAfter' in this case
+                        self?.viewModel.pagedDataObserver?.load(section?.model == .loadOlder ?
+                            .pageAfter :
+                            .pageBefore
+                        )
                         return
                         
                     default: continue
@@ -242,7 +253,7 @@ public class MediaTileViewController: UIViewController, UICollectionViewDataSour
     }
     
     private func stopObservingChanges() {
-        // Note: The 'PagedDatabaseObserver' will continue to get changes but
+        // Note: The 'pagedDataObserver' will continue to get changes but
         // we don't want to trigger any UI updates
         self.viewModel.onGalleryChange = nil
     }
@@ -261,8 +272,8 @@ public class MediaTileViewController: UIViewController, UICollectionViewDataSour
         // Determine if we are inserting content at the top of the collectionView
         let isInsertingAtTop: Bool = {
             let oldFirstSectionIsLoadMore: Bool = (
-                self.viewModel.galleryData[safe: 0]?.model == .loadNewer ||
-                self.viewModel.galleryData[safe: 0]?.model == .loadOlder
+                self.viewModel.galleryData.first?.model == .loadNewer ||
+                self.viewModel.galleryData.first?.model == .loadOlder
             )
             let oldTargetSectionIndex: Int = (oldFirstSectionIsLoadMore ? 1 : 0)
             
@@ -399,41 +410,17 @@ public class MediaTileViewController: UIViewController, UICollectionViewDataSour
         guard self.hasLoadedInitialData else { return }
         
         let section: MediaGalleryViewModel.SectionModel = self.viewModel.galleryData[indexPath.section]
-        let fastEndScrollingThen: ((@escaping () -> ()) -> ()) = { callback in
-            let endOffset: CGPoint
-            
-            if let currentTargetOffset: CGPoint = self.currentTargetOffset {
-                endOffset = currentTargetOffset
-            }
-            else {
-                let currentVelocity: CGPoint = collectionView.panGestureRecognizer.velocity(in: collectionView)
-                
-                endOffset = CGPoint(
-                    x: collectionView.contentOffset.x,
-                    y: collectionView.contentOffset.y - (currentVelocity.y / 100)
-                )
-            }
-            
-            guard endOffset != collectionView.contentOffset else {
-                return callback()
-            }
-            
-            UIView.animate(
-                withDuration: 0.1,
-                delay: 0,
-                options: .curveEaseOut,
-                animations: {
-                    collectionView.setContentOffset(endOffset, animated: false)
-                },
-                completion: { _ in
-                    callback()
-                }
-            )
-        }
         
         switch section.model {
-            case .loadOlder: fastEndScrollingThen { self.viewModel.loadOlderGalleryItems() }
-            case .loadNewer: fastEndScrollingThen { self.viewModel.loadNewerGalleryItems() }
+            case .loadOlder, .loadNewer:
+                UIScrollView.fastEndScrollingThen(collectionView, self.currentTargetOffset) { [weak self] in
+                    // Attachments are loaded in descending order so 'loadOlder' actually corresponds with
+                    // 'pageAfter' in this case
+                    self?.viewModel.pagedDataObserver?.load(section.model == .loadOlder ?
+                        .pageAfter :
+                        .pageBefore
+                    )
+                }
                 
             case .emptyGallery, .galleryMonth: break
         }

Session/Utilities/UIScrollView+Utilities.swift

@@ -0,0 +1,37 @@
+// Copyright © 2022 Rangeproof Pty Ltd. All rights reserved.
+
+import UIKit
+
+public extension UIScrollView {
+    static let fastEndScrollingThen: ((UIScrollView, CGPoint?, @escaping () -> ()) -> ()) = { scrollView, currentTargetOffset, callback in
+        let endOffset: CGPoint
+        
+        if let currentTargetOffset: CGPoint = currentTargetOffset {
+            endOffset = currentTargetOffset
+        }
+        else {
+            let currentVelocity: CGPoint = scrollView.panGestureRecognizer.velocity(in: scrollView)
+            
+            endOffset = CGPoint(
+                x: scrollView.contentOffset.x,
+                y: scrollView.contentOffset.y - (currentVelocity.y / 100)
+            )
+        }
+        
+        guard endOffset != scrollView.contentOffset else {
+            return callback()
+        }
+        
+        UIView.animate(
+            withDuration: 0.1,
+            delay: 0,
+            options: .curveEaseOut,
+            animations: {
+                scrollView.setContentOffset(endOffset, animated: false)
+            },
+            completion: { _ in
+                callback()
+            }
+        )
+    }
+}

SessionMessagingKit/Shared Models/ConversationCellViewModel.swift

@@ -198,9 +198,9 @@ extension ConversationCell {
 // MARK: - Convenience Initialization
 
 public extension ConversationCell.ViewModel {
-    // Note: This init method is only used for the message requests cell on the home screen so we can avoid having
-    init(unreadCount: UInt) {
-        self.threadId = "UNREAD_MESSAGE_REQUEST_THREADS"
+    // Note: This init method is only used for the message requests cell or empty states
+    init(unreadCount: UInt = 0) {
+        self.threadId = "INVALID_THREAD_ID"
         self.threadVariant = .contact
         self.threadCreationDateTimestamp = 0
         self.threadMemberNames = nil
@@ -1175,6 +1175,51 @@ public extension ConversationCell.ViewModel {
             ])
         }
     }
+    
+    /// This method returns only the 'Note to Self' thread in the structure of a search result conversation
+    static func noteToSelfOnlyQuery(userPublicKey: String) -> AdaptedFetchRequest<SQLRequest<ConversationCell.ViewModel>> {
+        let thread: TypedTableAlias<SessionThread> = TypedTableAlias()
+        let profileIdColumnLiteral: SQL = SQL(stringLiteral: Profile.Columns.id.name)
+        
+        /// **Note:** The `numColumnsBeforeProfiles` value **MUST** match the number of fields before
+        /// the `ViewModel.contactProfileKey` entry below otherwise the query will fail to
+        /// parse and might throw
+        let numColumnsBeforeProfiles: Int = 7
+        let request: SQLRequest<ViewModel> = """
+            SELECT
+                100 AS \(Column.rank),
+                
+                \(thread[.id]) AS \(ViewModel.threadIdKey),
+                \(thread[.variant]) AS \(ViewModel.threadVariantKey),
+                \(thread[.creationDateTimestamp]) AS \(ViewModel.threadCreationDateTimestampKey),
+                '' AS \(ViewModel.threadMemberNamesKey),
+                
+                true AS \(ViewModel.threadIsNoteToSelfKey),
+                \(thread[.isPinned]) AS \(ViewModel.threadIsPinnedKey),
+                
+                \(ViewModel.contactProfileKey).*,
+                
+                \(SQL("\(userPublicKey)")) AS \(ViewModel.currentUserPublicKeyKey)
+
+            FROM \(SessionThread.self)
+            JOIN \(Profile.self) AS \(ViewModel.contactProfileKey) ON \(ViewModel.contactProfileKey).\(profileIdColumnLiteral) = \(thread[.id])
+        
+            WHERE \(SQL("\(thread[.id]) = \(userPublicKey)"))
+        """
+        
+        // Add adapters which will group the various 'Profile' columns so they can be decoded
+        // as instances of 'Profile' types
+        return request.adapted { db in
+            let adapters = try splittingRowAdapters(columnCounts: [
+                numColumnsBeforeProfiles,
+                Profile.numberOfSelectedColumns(db)
+            ])
+
+            return ScopeAdapter([
+                ViewModel.contactProfileString: adapters[1]
+            ])
+        }
+    }
 }
 
 // MARK: - Share Extension

SessionUtilitiesKit/Database/Types/PagedDatabaseObserver.swift

@@ -450,6 +450,7 @@ public class PagedDatabaseObserver<ObservedTable, T>: TransactionObserver where
             if let updatedPageInfo: PagedData.PageInfo = loadedPage?.pageInfo {
                 self.pageInfo.mutate { $0 = updatedPageInfo }
             }
+            self.isLoadingMoreData.mutate { $0 = false }
             return
         }
         

SignalUtilitiesKit/Utilities/UIView+OWS.swift

@@ -137,7 +137,7 @@ public extension UIViewController {
     }
 
     func presentAlert(_ alert: UIAlertController, animated: Bool) {
-        if !Thread.isMainThread {
+        guard Thread.isMainThread else {
             DispatchQueue.main.async { [weak self] in
                 self?.presentAlert(alert, animated: animated)
             }
@@ -150,7 +150,7 @@ public extension UIViewController {
     }
 
     func presentAlert(_ alert: UIAlertController, completion: @escaping (() -> Void)) {
-        if !Thread.isMainThread {
+        guard Thread.isMainThread else {
             DispatchQueue.main.async { [weak self] in
                 self?.presentAlert(alert, completion: completion)
             }