Conversations

DB/Sources/DB/Content/ContentDatabase+Migration.swift

@@ -105,6 +105,21 @@ extension ContentDatabase {
                 t.column("wholeWord", .boolean).notNull()
             }
 
+            try db.create(table: "conversationRecord") { t in
+                t.column("id", .text).primaryKey(onConflict: .replace)
+                t.column("unread", .boolean).notNull()
+                t.column("lastStatusId", .text).references("statusRecord")
+            }
+
+            try db.create(table: "conversationAccountJoin") { t in
+                t.column("conversationId", .text).indexed().notNull()
+                    .references("conversationRecord", onDelete: .cascade)
+                t.column("accountId", .text).indexed().notNull()
+                    .references("accountRecord", onDelete: .cascade)
+
+                t.primaryKey(["conversationId", "accountId"], onConflict: .replace)
+            }
+
             try db.create(table: "lastReadIdRecord") { t in
                 t.column("markerTimeline", .text).primaryKey(onConflict: .replace)
                 t.column("id", .text).notNull()

DB/Sources/DB/Content/ContentDatabase.swift

@@ -302,6 +302,16 @@ public extension ContentDatabase {
         .eraseToAnyPublisher()
     }
 
+    func insert(conversations: [Conversation]) -> AnyPublisher<Never, Error> {
+        databaseWriter.writePublisher {
+            for conversation in conversations {
+                try conversation.save($0)
+            }
+        }
+        .ignoreOutput()
+        .eraseToAnyPublisher()
+    }
+
     func timelinePublisher(_ timeline: Timeline) -> AnyPublisher<[[CollectionItem]], Error> {
         ValueObservation.tracking(
             TimelineItemsInfo.request(TimelineRecord.filter(TimelineRecord.Columns.id == timeline.id)).fetchOne)
@@ -378,6 +388,17 @@ public extension ContentDatabase {
             .eraseToAnyPublisher()
     }
 
+    func conversationsPublisher() -> AnyPublisher<[Conversation], Error> {
+        ValueObservation.tracking(ConversationInfo.request(ConversationRecord.all()).fetchAll)
+            .removeDuplicates()
+            .publisher(in: databaseWriter)
+            .map {
+                $0.sorted { $0.lastStatusInfo.record.createdAt > $1.lastStatusInfo.record.createdAt }
+                    .map(Conversation.init(info:))
+            }
+            .eraseToAnyPublisher()
+    }
+
     func lastReadId(_ markerTimeline: Marker.Timeline) -> String? {
         try? databaseWriter.read {
             try String.fetchOne(
@@ -402,6 +423,8 @@ private extension ContentDatabase {
             let notificationAccountIds: [Account.Id]
             let notificationStatusIds: [Status.Id]
 
+            try ConversationRecord.deleteAll($0)
+
             if useNotificationsLastReadId {
                 var notificationIds = try MastodonNotification.Id.fetchAll(
                     $0,

DB/Sources/DB/Content/ConversationAccountJoin.swift

@@ -0,0 +1,19 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import GRDB
+import Mastodon
+
+struct ConversationAccountJoin: ContentDatabaseRecord {
+    let conversationId: Conversation.Id
+    let accountId: Account.Id
+}
+
+extension ConversationAccountJoin {
+    enum Columns {
+        static let conversationId = Column(ConversationAccountJoin.CodingKeys.conversationId)
+        static let accountId = Column(ConversationAccountJoin.CodingKeys.accountId)
+    }
+
+    static let account = belongsTo(AccountRecord.self)
+}

DB/Sources/DB/Content/ConversationInfo.swift

@@ -0,0 +1,22 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import GRDB
+
+struct ConversationInfo: Codable, Hashable, FetchableRecord {
+    let record: ConversationRecord
+    let accountInfos: [AccountInfo]
+    let lastStatusInfo: StatusInfo
+}
+
+extension ConversationInfo {
+    static func addingIncludes<T: DerivableRequest>(_ request: T) -> T where T.RowDecoder == ConversationRecord {
+        request.including(all: AccountInfo.addingIncludes(ConversationRecord.accounts).forKey(CodingKeys.accountInfos))
+            .including(required: StatusInfo.addingIncludes(ConversationRecord.lastStatus)
+                        .forKey(CodingKeys.lastStatusInfo))
+    }
+
+    static func request(_ request: QueryInterfaceRequest<ConversationRecord>) -> QueryInterfaceRequest<Self> {
+        addingIncludes(request).asRequest(of: self)
+    }
+}

DB/Sources/DB/Content/ConversationRecord.swift

@@ -0,0 +1,32 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import GRDB
+import Mastodon
+
+struct ConversationRecord: ContentDatabaseRecord, Hashable {
+    let id: Conversation.Id
+    let unread: Bool
+    let lastStatusId: Status.Id?
+}
+
+extension ConversationRecord {
+    enum Columns {
+        static let id = Column(ConversationRecord.CodingKeys.id)
+        static let unread = Column(ConversationRecord.CodingKeys.unread)
+        static let lastStatusId = Column(ConversationRecord.CodingKeys.lastStatusId)
+    }
+
+    static let lastStatus = belongsTo(StatusRecord.self)
+    static let accountJoins = hasMany(ConversationAccountJoin.self)
+    static let accounts = hasMany(
+        AccountRecord.self,
+        through: accountJoins,
+        using: ConversationAccountJoin.account)
+
+    init(conversation: Conversation) {
+        id = conversation.id
+        unread = conversation.unread
+        lastStatusId = conversation.lastStatus?.id
+    }
+}

DB/Sources/DB/Entities/CollectionItem.swift

@@ -7,6 +7,7 @@ public enum CollectionItem: Hashable {
     case loadMore(LoadMore)
     case account(Account)
     case notification(MastodonNotification, StatusConfiguration?)
+    case conversation(Conversation)
 }
 
 public extension CollectionItem {
@@ -45,6 +46,8 @@ public extension CollectionItem {
             return account.id
         case let .notification(notification, _):
             return notification.id
+        case let .conversation(conversation):
+            return conversation.id
         }
     }
 }

DB/Sources/DB/Extensions/Conversation+Extensions.swift

@@ -0,0 +1,27 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import GRDB
+import Mastodon
+
+extension Conversation {
+    func save(_ db: Database) throws {
+        guard let lastStatus = lastStatus else { return }
+
+        try lastStatus.save(db)
+        try ConversationRecord(conversation: self).save(db)
+
+        for account in accounts {
+            try account.save(db)
+            try ConversationAccountJoin(conversationId: id, accountId: account.id).save(db)
+        }
+    }
+
+    init(info: ConversationInfo) {
+        self.init(
+            id: info.record.id,
+            accounts: info.accountInfos.map(Account.init(info:)),
+            unread: info.record.unread,
+        lastStatus: Status(info: info.lastStatusInfo))
+    }
+}

Data Sources/TableViewDataSource.swift

@@ -26,6 +26,8 @@ final class TableViewDataSource: UITableViewDiffableDataSource<Int, CollectionIt
                 loadMoreCell.viewModel = loadMoreViewModel
             case let (notificationListCell as NotificationListCell, notificationViewModel as NotificationViewModel):
                 notificationListCell.viewModel = notificationViewModel
+            case let (conversationListCell as ConversationListCell, conversationViewModel as ConversationViewModel):
+                conversationListCell.viewModel = conversationViewModel
             default:
                 break
             }

Extensions/CollectionItem+Extensions.swift

@@ -8,7 +8,8 @@ extension CollectionItem {
         StatusListCell.self,
         AccountListCell.self,
         LoadMoreCell.self,
-        NotificationListCell.self]
+        NotificationListCell.self,
+        ConversationListCell.self]
 
     var cellClass: AnyClass {
         switch self {
@@ -20,6 +21,8 @@ extension CollectionItem {
             return LoadMoreCell.self
         case let .notification(_, statusConfiguration):
             return statusConfiguration == nil ? NotificationListCell.self : StatusListCell.self
+        case .conversation:
+            return ConversationListCell.self
         }
     }
 }

Localizations/Localizable.strings

@@ -31,6 +31,7 @@
 "identities.pending" = "Pending";
 "lists.new-list-title" = "New List Title";
 "load-more" = "Load More";
+"messages" = "Messages";
 "pending.pending-confirmation" = "Your account is pending confirmation";
 "preferences" = "Preferences";
 "preferences.app" = "App Preferences";

Mastodon/Sources/Mastodon/Entities/Conversation.swift

@@ -0,0 +1,21 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+
+public struct Conversation: Codable, Hashable {
+    public let id: Id
+    public let accounts: [Account]
+    public let unread: Bool
+    public let lastStatus: Status?
+
+    public init(id: String, accounts: [Account], unread: Bool, lastStatus: Status?) {
+        self.id = id
+        self.accounts = accounts
+        self.unread = unread
+        self.lastStatus = lastStatus
+    }
+}
+
+public extension Conversation {
+    typealias Id = String
+}

MastodonAPI/Sources/MastodonAPI/Endpoints/ConversationsEndpoint.swift

@@ -0,0 +1,19 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import HTTP
+import Mastodon
+
+public enum ConversationsEndpoint {
+    case conversations
+}
+
+extension ConversationsEndpoint: Endpoint {
+    public typealias ResultType = [Conversation]
+
+    public var pathComponentsInContext: [String] {
+        ["conversations"]
+    }
+
+    public var method: HTTPMethod { .get }
+}

Metatext.xcodeproj/project.pbxproj

@@ -8,6 +8,10 @@
 
 /* Begin PBXBuildFile section */
 		D0030982250C6C8500EACB32 /* URL+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0030981250C6C8500EACB32 /* URL+Extensions.swift */; };
+		D00702292555E51200F38136 /* ConversationListCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D00702282555E51200F38136 /* ConversationListCell.swift */; };
+		D00702312555F4AE00F38136 /* ConversationView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D00702302555F4AE00F38136 /* ConversationView.swift */; };
+		D00702362555F4C500F38136 /* ConversationContentConfiguration.swift in Sources */ = {isa = PBXBuildFile; fileRef = D00702352555F4C500F38136 /* ConversationContentConfiguration.swift */; };
+		D007023E25562A2800F38136 /* ConversationAvatarsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D007023D25562A2800F38136 /* ConversationAvatarsView.swift */; };
 		D00CB2ED2533ACC00080096B /* StatusView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D00CB2EC2533ACC00080096B /* StatusView.swift */; };
 		D01C6FAC252024BD003D0300 /* Array+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D01C6FAB252024BD003D0300 /* Array+Extensions.swift */; };
 		D01EF22425182B1F00650C6B /* AccountHeaderView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D01EF22325182B1F00650C6B /* AccountHeaderView.swift */; };
@@ -116,6 +120,10 @@
 
 /* Begin PBXFileReference section */
 		D0030981250C6C8500EACB32 /* URL+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "URL+Extensions.swift"; sourceTree = "<group>"; };
+		D00702282555E51200F38136 /* ConversationListCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConversationListCell.swift; sourceTree = "<group>"; };
+		D00702302555F4AE00F38136 /* ConversationView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConversationView.swift; sourceTree = "<group>"; };
+		D00702352555F4C500F38136 /* ConversationContentConfiguration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConversationContentConfiguration.swift; sourceTree = "<group>"; };
+		D007023D25562A2800F38136 /* ConversationAvatarsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConversationAvatarsView.swift; sourceTree = "<group>"; };
 		D00CB2EC2533ACC00080096B /* StatusView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusView.swift; sourceTree = "<group>"; };
 		D01C6FAB252024BD003D0300 /* Array+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Array+Extensions.swift"; sourceTree = "<group>"; };
 		D01EF22325182B1F00650C6B /* AccountHeaderView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AccountHeaderView.swift; sourceTree = "<group>"; };
@@ -338,6 +346,10 @@
 				D0F0B125251A90F400942152 /* AccountListCell.swift */,
 				D0F0B10D251A868200942152 /* AccountView.swift */,
 				D0C7D42424F76169001EBDBB /* AddIdentityView.swift */,
+				D007023D25562A2800F38136 /* ConversationAvatarsView.swift */,
+				D00702352555F4C500F38136 /* ConversationContentConfiguration.swift */,
+				D00702282555E51200F38136 /* ConversationListCell.swift */,
+				D00702302555F4AE00F38136 /* ConversationView.swift */,
 				D0C7D42324F76169001EBDBB /* CustomEmojiText.swift */,
 				D0BEB21024FA2A90001B0F04 /* EditFilterView.swift */,
 				D0BEB20424FA1107001B0F04 /* FiltersView.swift */,
@@ -606,6 +618,7 @@
 			files = (
 				D0C7D4A324F7616A001EBDBB /* TabNavigationView.swift in Sources */,
 				D02E1F95250B13210071AD56 /* SafariView.swift in Sources */,
+				D00702292555E51200F38136 /* ConversationListCell.swift in Sources */,
 				D03B1B2A253818F3008F964B /* MediaPreferencesView.swift in Sources */,
 				D0C7D49C24F7616A001EBDBB /* RootView.swift in Sources */,
 				D0F0B126251A90F400942152 /* AccountListCell.swift in Sources */,
@@ -615,6 +628,7 @@
 				D0E569E0252931B100FA1D72 /* LoadMoreContentConfiguration.swift in Sources */,
 				D0FE1C9825368A9D003EF1EB /* PlayerCache.swift in Sources */,
 				D0F0B136251AA12700942152 /* CollectionItem+Extensions.swift in Sources */,
+				D007023E25562A2800F38136 /* ConversationAvatarsView.swift in Sources */,
 				D0625E5D250F0B5C00502611 /* StatusContentConfiguration.swift in Sources */,
 				D0BEB1F324F8EE8C001B0F04 /* StatusAttachmentView.swift in Sources */,
 				D0C7D49A24F7616A001EBDBB /* TableView.swift in Sources */,
@@ -638,6 +652,7 @@
 				D08B8D8D2544E6EC00B1EBEF /* PollResultView.swift in Sources */,
 				D0C7D4D524F7616A001EBDBB /* String+Extensions.swift in Sources */,
 				D0C7D4A224F7616A001EBDBB /* NotificationTypesPreferencesView.swift in Sources */,
+				D00702362555F4C500F38136 /* ConversationContentConfiguration.swift in Sources */,
 				D0BEB1F724F9A84B001B0F04 /* LoadingTableFooterView.swift in Sources */,
 				D06BC5E625202AD90079541D /* ProfileViewController.swift in Sources */,
 				D01C6FAC252024BD003D0300 /* Array+Extensions.swift in Sources */,
@@ -656,6 +671,7 @@
 				D08B8D3D253F929E00B1EBEF /* ImageViewController.swift in Sources */,
 				D0B8510C25259E56004E0744 /* LoadMoreCell.swift in Sources */,
 				D01F41E424F8889700D55A2D /* StatusAttachmentsView.swift in Sources */,
+				D00702312555F4AE00F38136 /* ConversationView.swift in Sources */,
 				D0BEB21124FA2A91001B0F04 /* EditFilterView.swift in Sources */,
 				D08B8D4A253FC36500B1EBEF /* ImageNavigationController.swift in Sources */,
 				D0030982250C6C8500EACB32 /* URL+Extensions.swift in Sources */,

ServiceLayer/Sources/ServiceLayer/Services/ConversationService.swift

@@ -0,0 +1,23 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Combine
+import DB
+import Foundation
+import Mastodon
+import MastodonAPI
+
+public struct ConversationService {
+    public let conversation: Conversation
+    public let navigationService: NavigationService
+    private let mastodonAPIClient: MastodonAPIClient
+    private let contentDatabase: ContentDatabase
+
+    init(conversation: Conversation, mastodonAPIClient: MastodonAPIClient, contentDatabase: ContentDatabase) {
+        self.conversation = conversation
+        self.navigationService = NavigationService(
+            mastodonAPIClient: mastodonAPIClient,
+            contentDatabase: contentDatabase)
+        self.mastodonAPIClient = mastodonAPIClient
+        self.contentDatabase = contentDatabase
+    }
+}

ServiceLayer/Sources/ServiceLayer/Services/ConversationsService.swift

@@ -0,0 +1,40 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Combine
+import DB
+import Foundation
+import Mastodon
+import MastodonAPI
+
+public struct ConversationsService {
+    public let sections: AnyPublisher<[[CollectionItem]], Error>
+    public let nextPageMaxId: AnyPublisher<String, Never>
+    public let navigationService: NavigationService
+
+    private let mastodonAPIClient: MastodonAPIClient
+    private let contentDatabase: ContentDatabase
+    private let nextPageMaxIdSubject = PassthroughSubject<String, Never>()
+
+    init(mastodonAPIClient: MastodonAPIClient, contentDatabase: ContentDatabase) {
+        self.mastodonAPIClient = mastodonAPIClient
+        self.contentDatabase = contentDatabase
+        sections = contentDatabase.conversationsPublisher()
+            .map { [$0.map(CollectionItem.conversation)] }
+            .eraseToAnyPublisher()
+        nextPageMaxId = nextPageMaxIdSubject.eraseToAnyPublisher()
+        navigationService = NavigationService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
+    }
+}
+
+extension ConversationsService: CollectionService {
+    public func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error> {
+        mastodonAPIClient.pagedRequest(ConversationsEndpoint.conversations, maxId: maxId, minId: minId)
+            .handleEvents(receiveOutput: {
+                guard let maxId = $0.info.maxId else { return }
+
+                nextPageMaxIdSubject.send(maxId)
+            })
+            .flatMap { contentDatabase.insert(conversations: $0.result) }
+            .eraseToAnyPublisher()
+    }
+}

ServiceLayer/Sources/ServiceLayer/Services/IdentityService.swift

@@ -212,6 +212,10 @@ public extension IdentityService {
     func notificationsService() -> NotificationsService {
         NotificationsService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
     }
+
+    func conversationsService() -> ConversationsService {
+        ConversationsService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
+    }
 }
 
 private extension IdentityService {

ServiceLayer/Sources/ServiceLayer/Services/NavigationService.swift

@@ -79,6 +79,13 @@ public extension NavigationService {
             mastodonAPIClient: mastodonAPIClient,
             contentDatabase: contentDatabase)
     }
+
+    func conversationService(conversation: Conversation) -> ConversationService {
+        ConversationService(
+            conversation: conversation,
+            mastodonAPIClient: mastodonAPIClient,
+            contentDatabase: contentDatabase)
+    }
 }
 
 private extension NavigationService {

ViewModels/Sources/ViewModels/CollectionItemsViewModel.swift

@@ -140,6 +140,13 @@ extension CollectionItemsViewModel: CollectionViewModel {
                                             .navigationService
                                             .profileService(account: notification.account))))
             }
+        case let .conversation(conversation):
+            guard let status = conversation.lastStatus else { break }
+
+            eventsSubject.send(
+                .navigation(.collection(collectionService
+                                            .navigationService
+                                            .contextService(id: status.displayStatus.id))))
         }
     }
 
@@ -164,7 +171,7 @@ extension CollectionItemsViewModel: CollectionViewModel {
         }
     }
 
-    // swiftlint:disable:next function_body_length
+    // swiftlint:disable:next function_body_length cyclomatic_complexity
     public func viewModel(indexPath: IndexPath) -> CollectionItemViewModel {
         let item = items.value[indexPath.section][indexPath.item]
         let cachedViewModel = viewModelCache[item]?.viewModel
@@ -228,6 +235,19 @@ extension CollectionItemsViewModel: CollectionViewModel {
                 cache(viewModel: viewModel, forItem: item)
             }
 
+            return viewModel
+        case let .conversation(conversation):
+            if let cachedViewModel = cachedViewModel {
+                return cachedViewModel
+            }
+
+            let viewModel = ConversationViewModel(
+                conversationService: collectionService.navigationService.conversationService(
+                    conversation: conversation),
+                identification: identification)
+
+            cache(viewModel: viewModel, forItem: item)
+
             return viewModel
         }
     }

ViewModels/Sources/ViewModels/ConversationViewModel.swift

@@ -0,0 +1,36 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Combine
+import Foundation
+import Mastodon
+import ServiceLayer
+
+public final class ConversationViewModel: CollectionItemViewModel, ObservableObject {
+    public let accountViewModels: [AccountViewModel]
+    public let statusViewModel: StatusViewModel?
+    public let events: AnyPublisher<AnyPublisher<CollectionItemEvent, Error>, Never>
+
+    private let conversationService: ConversationService
+    private let identification: Identification
+    private let eventsSubject = PassthroughSubject<AnyPublisher<CollectionItemEvent, Error>, Never>()
+
+    init(conversationService: ConversationService, identification: Identification) {
+        accountViewModels = conversationService.conversation.accounts.map {
+            AccountViewModel(
+                accountService: conversationService.navigationService.accountService(account: $0),
+                identification: identification)
+        }
+
+        if let status = conversationService.conversation.lastStatus {
+            statusViewModel = StatusViewModel(
+                statusService: conversationService.navigationService.statusService(status: status),
+                identification: identification)
+        } else {
+            statusViewModel = nil
+        }
+
+        self.conversationService = conversationService
+        self.identification = identification
+        self.events = eventsSubject.eraseToAnyPublisher()
+    }
+}

ViewModels/Sources/ViewModels/NavigationViewModel.swift

@@ -34,7 +34,22 @@ public final class NavigationViewModel: ObservableObject {
         }
     }
 
+    public var conversationsViewModel: CollectionViewModel? {
+        if identification.identity.authenticated {
+            if _conversationsViewModel == nil {
+                _conversationsViewModel = CollectionItemsViewModel(
+                    collectionService: identification.service.conversationsService(),
+                    identification: identification)
+            }
+
+            return _conversationsViewModel
+        } else {
+            return nil
+        }
+    }
+
     private var _notificationsViewModel: CollectionViewModel?
+    private var _conversationsViewModel: CollectionViewModel?
     private var cancellables = Set<AnyCancellable>()
 
     public init(identification: Identification) {

Views/ConversationAvatarsView.swift

@@ -0,0 +1,88 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Kingfisher
+import UIKit
+import ViewModels
+
+final class ConversationAvatarsView: UIView {
+    private let leftStackView = UIStackView()
+    private let rightStackView = UIStackView()
+
+    var viewModel: ConversationViewModel? {
+        didSet {
+            for stackView in [leftStackView, rightStackView] {
+                for view in stackView.arrangedSubviews {
+                    stackView.removeArrangedSubview(view)
+                    view.removeFromSuperview()
+                }
+            }
+
+            let accountViewModels = viewModel?.accountViewModels ?? []
+            let accountCount = accountViewModels.count
+
+            rightStackView.isHidden = accountCount == 1
+
+            for (index, accountViewModel) in accountViewModels.enumerated() {
+                let imageView = AnimatedImageView()
+
+                imageView.contentMode = .scaleAspectFill
+                imageView.clipsToBounds = true
+                imageView.kf.setImage(with: accountViewModel.avatarURL())
+
+                if accountCount == 2 && index == 1
+                    || accountCount == 3 && index != 0
+                    || accountCount > 3 && index % 2 != 0 {
+                    rightStackView.addArrangedSubview(imageView)
+                } else {
+                    leftStackView.addArrangedSubview(imageView)
+                }
+            }
+        }
+    }
+
+    override init(frame: CGRect) {
+        super.init(frame: frame)
+
+        initialSetup()
+    }
+
+    @available(*, unavailable)
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    override func layoutSubviews() {
+        super.layoutSubviews()
+
+        layer.cornerRadius = bounds.height / 2
+    }
+}
+
+private extension ConversationAvatarsView {
+    func initialSetup() {
+        backgroundColor = .clear
+        clipsToBounds = true
+
+        let containerStackView = UIStackView()
+
+        addSubview(containerStackView)
+        containerStackView.translatesAutoresizingMaskIntoConstraints = false
+        containerStackView.distribution = .fillEqually
+        containerStackView.spacing = .ultraCompactSpacing
+        leftStackView.distribution = .fillEqually
+        leftStackView.spacing = .ultraCompactSpacing
+        leftStackView.axis = .vertical
+        rightStackView.distribution = .fillEqually
+        rightStackView.spacing = .ultraCompactSpacing
+        rightStackView.axis = .vertical
+        containerStackView.addArrangedSubview(leftStackView)
+        containerStackView.addArrangedSubview(rightStackView)
+
+        NSLayoutConstraint.activate([
+            containerStackView.leadingAnchor.constraint(equalTo: leadingAnchor),
+            containerStackView.trailingAnchor.constraint(equalTo: trailingAnchor),
+            containerStackView.topAnchor.constraint(equalTo: topAnchor),
+            containerStackView.bottomAnchor.constraint(equalTo: bottomAnchor)
+        ])
+    }
+}

Views/ConversationContentConfiguration.swift

@@ -0,0 +1,18 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import UIKit
+import ViewModels
+
+struct ConversationContentConfiguration {
+    let viewModel: ConversationViewModel
+}
+
+extension ConversationContentConfiguration: UIContentConfiguration {
+    func makeContentView() -> UIView & UIContentView {
+        ConversationView(configuration: self)
+    }
+
+    func updated(for state: UIConfigurationState) -> ConversationContentConfiguration {
+        self
+    }
+}

Views/ConversationListCell.swift

@@ -0,0 +1,26 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import UIKit
+import ViewModels
+
+class ConversationListCell: UITableViewCell {
+    var viewModel: ConversationViewModel?
+
+    override func updateConfiguration(using state: UICellConfigurationState) {
+        guard let viewModel = viewModel else { return }
+
+        contentConfiguration = ConversationContentConfiguration(viewModel: viewModel).updated(for: state)
+    }
+
+    override func layoutSubviews() {
+        super.layoutSubviews()
+
+        if UIDevice.current.userInterfaceIdiom == .phone {
+            separatorInset.left = 0
+            separatorInset.right = 0
+        } else {
+            separatorInset.left = layoutMargins.left
+            separatorInset.right = layoutMargins.right
+        }
+    }
+}

Views/ConversationView.swift

@@ -0,0 +1,99 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import UIKit
+
+final class ConversationView: UIView {
+    let avatarsView = ConversationAvatarsView()
+    let displayNamesLabel = UILabel()
+    let statusBodyView = StatusBodyView()
+
+    private var conversationConfiguration: ConversationContentConfiguration
+
+    init(configuration: ConversationContentConfiguration) {
+        conversationConfiguration = configuration
+
+        super.init(frame: .zero)
+
+        initialSetup()
+        applyConversationConfiguration()
+    }
+
+    @available(*, unavailable)
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+}
+
+extension ConversationView: UIContentView {
+    var configuration: UIContentConfiguration {
+        get { conversationConfiguration }
+        set {
+            guard let conversationConfiguration = newValue as? ConversationContentConfiguration else { return }
+
+            self.conversationConfiguration = conversationConfiguration
+
+            applyConversationConfiguration()
+        }
+    }
+}
+
+private extension ConversationView {
+    func initialSetup() {
+        let containerStackView = UIStackView()
+        let sideStackView = UIStackView()
+        let mainStackView = UIStackView()
+
+        addSubview(containerStackView)
+        containerStackView.translatesAutoresizingMaskIntoConstraints = false
+        containerStackView.spacing = .defaultSpacing
+
+        sideStackView.axis = .vertical
+        sideStackView.alignment = .trailing
+        sideStackView.spacing = .compactSpacing
+        sideStackView.addArrangedSubview(avatarsView)
+        sideStackView.addArrangedSubview(UIView())
+        containerStackView.addArrangedSubview(sideStackView)
+
+        mainStackView.axis = .vertical
+        mainStackView.spacing = .compactSpacing
+        mainStackView.addArrangedSubview(displayNamesLabel)
+        mainStackView.addSubview(UIView())
+        mainStackView.addArrangedSubview(statusBodyView)
+        containerStackView.addArrangedSubview(mainStackView)
+
+        displayNamesLabel.font = .preferredFont(forTextStyle: .headline)
+        displayNamesLabel.adjustsFontForContentSizeCategory = true
+
+        statusBodyView.alpha = 0.5
+        statusBodyView.isUserInteractionEnabled = false
+
+        let avatarsHeightConstraint = avatarsView.heightAnchor.constraint(equalToConstant: .avatarDimension)
+
+        avatarsHeightConstraint.priority = .justBelowMax
+
+        NSLayoutConstraint.activate([
+            containerStackView.leadingAnchor.constraint(equalTo: readableContentGuide.leadingAnchor),
+            containerStackView.topAnchor.constraint(equalTo: readableContentGuide.topAnchor),
+            containerStackView.trailingAnchor.constraint(equalTo: readableContentGuide.trailingAnchor),
+            containerStackView.bottomAnchor.constraint(equalTo: readableContentGuide.bottomAnchor),
+            avatarsView.widthAnchor.constraint(equalToConstant: .avatarDimension),
+            avatarsHeightConstraint,
+            sideStackView.widthAnchor.constraint(equalToConstant: .avatarDimension)
+        ])
+    }
+
+    func applyConversationConfiguration() {
+        let viewModel = conversationConfiguration.viewModel
+        let displayNames = ListFormatter.localizedString(byJoining: viewModel.accountViewModels.map(\.displayName))
+        let mutableDisplayNames = NSMutableAttributedString(string: displayNames)
+
+        mutableDisplayNames.insert(
+            emoji: viewModel.accountViewModels.map(\.emoji).reduce([], +),
+            view: displayNamesLabel)
+        mutableDisplayNames.resizeAttachments(toLineHeight: displayNamesLabel.font.lineHeight)
+
+        displayNamesLabel.attributedText = mutableDisplayNames
+        statusBodyView.viewModel = viewModel.statusViewModel
+        avatarsView.viewModel = viewModel
+    }
+}

Views/TabNavigationView.swift

@@ -58,6 +58,7 @@ private extension TabNavigationView {
     }
 
     @ViewBuilder
+    // swiftlint:disable:next function_body_length
     func view(tab: NavigationViewModel.Tab) -> some View {
         switch tab {
         case .timelines:
@@ -101,6 +102,15 @@ private extension TabNavigationView {
                     .navigationBarTitleDisplayMode(.inline)
                     .navigationBarItems(leading: secondaryNavigationButton)
             }
+        case .messages:
+            if let conversationsViewModel = viewModel.conversationsViewModel {
+                TableView(viewModel: conversationsViewModel)
+                    .id(tab)
+                    .edgesIgnoringSafeArea(.all)
+                    .navigationTitle("messages")
+                    .navigationBarTitleDisplayMode(.inline)
+                    .navigationBarItems(leading: secondaryNavigationButton)
+            }
         default: Text(tab.title)
         }
     }

Views/ViewConstants.swift

@@ -5,6 +5,7 @@ import SwiftUI
 extension CGFloat {
     static let defaultSpacing: Self = 8
     static let compactSpacing: Self = 4
+    static let ultraCompactSpacing: Self = 1
     static let defaultCornerRadius: Self = 8
     static let avatarDimension: Self = 50
     static let hairline = 1 / UIScreen.main.scale