feat: add Community tab into discovery scene

Mastodon.xcodeproj/project.pbxproj

@@ -233,6 +233,12 @@
 		DB3E6FF52807C40300B035AE /* DiscoveryForYouViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3E6FF42807C40300B035AE /* DiscoveryForYouViewController.swift */; };
 		DB3E6FF82807C45300B035AE /* DiscoveryForYouViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3E6FF72807C45300B035AE /* DiscoveryForYouViewModel.swift */; };
 		DB3E6FFA2807C47900B035AE /* DiscoveryForYouViewModel+Diffable.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3E6FF92807C47900B035AE /* DiscoveryForYouViewModel+Diffable.swift */; };
+		DB3EA8E6281B79E200598866 /* DiscoveryCommunityViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3EA8E5281B79E200598866 /* DiscoveryCommunityViewController.swift */; };
+		DB3EA8E9281B7A3700598866 /* DiscoveryCommunityViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3EA8E8281B7A3700598866 /* DiscoveryCommunityViewModel.swift */; };
+		DB3EA8EB281B7E0700598866 /* DiscoveryCommunityViewModel+State.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3EA8EA281B7E0700598866 /* DiscoveryCommunityViewModel+State.swift */; };
+		DB3EA8ED281B810100598866 /* APIService+PublicTimeline.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3EA8EC281B810100598866 /* APIService+PublicTimeline.swift */; };
+		DB3EA8EF281B837000598866 /* DiscoveryCommunityViewController+DataSourceProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3EA8EE281B837000598866 /* DiscoveryCommunityViewController+DataSourceProvider.swift */; };
+		DB3EA8F1281B9EF600598866 /* DiscoveryCommunityViewModel+Diffable.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB3EA8F0281B9EF600598866 /* DiscoveryCommunityViewModel+Diffable.swift */; };
 		DB427DD625BAA00100D1B89D /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB427DD525BAA00100D1B89D /* AppDelegate.swift */; };
 		DB427DD825BAA00100D1B89D /* SceneDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB427DD725BAA00100D1B89D /* SceneDelegate.swift */; };
 		DB427DDD25BAA00100D1B89D /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = DB427DDB25BAA00100D1B89D /* Main.storyboard */; };
@@ -962,6 +968,12 @@
 		DB3E6FF42807C40300B035AE /* DiscoveryForYouViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DiscoveryForYouViewController.swift; sourceTree = "<group>"; };
 		DB3E6FF72807C45300B035AE /* DiscoveryForYouViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DiscoveryForYouViewModel.swift; sourceTree = "<group>"; };
 		DB3E6FF92807C47900B035AE /* DiscoveryForYouViewModel+Diffable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "DiscoveryForYouViewModel+Diffable.swift"; sourceTree = "<group>"; };
+		DB3EA8E5281B79E200598866 /* DiscoveryCommunityViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DiscoveryCommunityViewController.swift; sourceTree = "<group>"; };
+		DB3EA8E8281B7A3700598866 /* DiscoveryCommunityViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DiscoveryCommunityViewModel.swift; sourceTree = "<group>"; };
+		DB3EA8EA281B7E0700598866 /* DiscoveryCommunityViewModel+State.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "DiscoveryCommunityViewModel+State.swift"; sourceTree = "<group>"; };
+		DB3EA8EC281B810100598866 /* APIService+PublicTimeline.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "APIService+PublicTimeline.swift"; sourceTree = "<group>"; };
+		DB3EA8EE281B837000598866 /* DiscoveryCommunityViewController+DataSourceProvider.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "DiscoveryCommunityViewController+DataSourceProvider.swift"; sourceTree = "<group>"; };
+		DB3EA8F0281B9EF600598866 /* DiscoveryCommunityViewModel+Diffable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "DiscoveryCommunityViewModel+Diffable.swift"; sourceTree = "<group>"; };
 		DB427DD225BAA00100D1B89D /* Mastodon.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = Mastodon.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		DB427DD525BAA00100D1B89D /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		DB427DD725BAA00100D1B89D /* SceneDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SceneDelegate.swift; sourceTree = "<group>"; };
@@ -2165,6 +2177,18 @@
 			path = ForYou;
 			sourceTree = "<group>";
 		};
+		DB3EA8E7281B79E500598866 /* Community */ = {
+			isa = PBXGroup;
+			children = (
+				DB3EA8E5281B79E200598866 /* DiscoveryCommunityViewController.swift */,
+				DB3EA8EE281B837000598866 /* DiscoveryCommunityViewController+DataSourceProvider.swift */,
+				DB3EA8E8281B7A3700598866 /* DiscoveryCommunityViewModel.swift */,
+				DB3EA8F0281B9EF600598866 /* DiscoveryCommunityViewModel+Diffable.swift */,
+				DB3EA8EA281B7E0700598866 /* DiscoveryCommunityViewModel+State.swift */,
+			);
+			path = Community;
+			sourceTree = "<group>";
+		};
 		DB427DC925BAA00100D1B89D = {
 			isa = PBXGroup;
 			children = (
@@ -2258,6 +2282,7 @@
 				2D9DB96A263A91D1007C1D71 /* APIService+DomainBlock.swift */,
 				DB45FB1C25CA9D23005A8AC7 /* APIService+HomeTimeline.swift */,
 				DB482A4A261340A7008AE74C /* APIService+UserTimeline.swift */,
+				DB3EA8EC281B810100598866 /* APIService+PublicTimeline.swift */,
 				DBA465922696B495002B41DB /* APIService+WebFinger.swift */,
 				DB0AC6FB25CD02E600D75117 /* APIService+Instance.swift */,
 				DB59F10D25EF724F001F1DAB /* APIService+Poll.swift */,
@@ -3128,6 +3153,7 @@
 				DBDFF19828055A0900557A48 /* Posts */,
 				DB3E6FDE2806A41200B035AE /* Hashtags */,
 				DB3E6FED2806D7FC00B035AE /* News */,
+				DB3EA8E7281B79E500598866 /* Community */,
 				DB3E6FF62807C40500B035AE /* ForYou */,
 				DBDFF19928055A1400557A48 /* DiscoveryViewController.swift */,
 				DBDFF19B28055BD600557A48 /* DiscoveryViewModel.swift */,
@@ -4049,6 +4075,7 @@
 				DB63F7452799056400455B82 /* HashtagTableViewCell.swift in Sources */,
 				DBD9149025DF6D8D00903DFD /* APIService+Onboarding.swift in Sources */,
 				DBAE3FAF26172FC0004B8251 /* RemoteProfileViewModel.swift in Sources */,
+				DB3EA8EB281B7E0700598866 /* DiscoveryCommunityViewModel+State.swift in Sources */,
 				DB0FCB7227952986006C02E2 /* NamingState.swift in Sources */,
 				DB73BF47271199CA00781945 /* Instance.swift in Sources */,
 				DB0F8150264D1E2500F2A12B /* PickServerLoaderTableViewCell.swift in Sources */,
@@ -4181,6 +4208,7 @@
 				DB040ED126538E3D00BEE9D8 /* Trie.swift in Sources */,
 				DB73BF4B27140C0800781945 /* UITableViewDiffableDataSource.swift in Sources */,
 				DBB525642612C988002F1F29 /* MeProfileViewModel.swift in Sources */,
+				DB3EA8EF281B837000598866 /* DiscoveryCommunityViewController+DataSourceProvider.swift in Sources */,
 				DB6B74EF272FB55000C70B6E /* FollowerListViewController.swift in Sources */,
 				DB4AA6B327BA34B6009EC082 /* CellFrameCacheContainer.swift in Sources */,
 				DB0FCB942797E2B0006C02E2 /* SearchResultViewModel+Diffable.swift in Sources */,
@@ -4222,10 +4250,12 @@
 				DB697DE1278F5296004EF2F7 /* DataSourceFacade+Model.swift in Sources */,
 				DBCC3B8F26148F7B0045B23D /* CachedProfileViewModel.swift in Sources */,
 				DB4F097526A037F500D62E92 /* SearchHistoryViewModel.swift in Sources */,
+				DB3EA8E9281B7A3700598866 /* DiscoveryCommunityViewModel.swift in Sources */,
 				DB6180F826391D660018D199 /* MediaPreviewingViewController.swift in Sources */,
 				DB0140CF25C42AEE00F9F3CF /* OSLog.swift in Sources */,
 				DB98EB5627B0FF1B0082E365 /* ReportViewControllerAppearance.swift in Sources */,
 				DB938F1526241FDF00E5B6C1 /* APIService+Thread.swift in Sources */,
+				DB3EA8E6281B79E200598866 /* DiscoveryCommunityViewController.swift in Sources */,
 				2D206B8625F5FB0900143C56 /* Double.swift in Sources */,
 				DB9F58F126EF512300E7BBE9 /* AccountListTableViewCell.swift in Sources */,
 				2D76319F25C1521200929FB9 /* StatusSection.swift in Sources */,
@@ -4276,6 +4306,7 @@
 				DB73BF45271195AC00781945 /* APIService+CoreData+Instance.swift in Sources */,
 				DB336F21278D6D960031E64B /* MastodonEmoji.swift in Sources */,
 				DB1D84382657B275000346B3 /* SegmentedControlNavigateable.swift in Sources */,
+				DB3EA8ED281B810100598866 /* APIService+PublicTimeline.swift in Sources */,
 				DB447697260B439000B66B82 /* CustomEmojiPickerHeaderCollectionReusableView.swift in Sources */,
 				DB025B97278D66D5002F581E /* MastodonUser+Property.swift in Sources */,
 				DB45FAF925CA80A2005A8AC7 /* APIService+CoreData+MastodonAuthentication.swift in Sources */,
@@ -4338,6 +4369,7 @@
 				DB9D6BFF25E4F5940051B173 /* ProfileViewController.swift in Sources */,
 				DB63F756279949BD00455B82 /* Persistence+SearchHistory.swift in Sources */,
 				2D4AD8A226316CD200613EFC /* SelectedAccountSection.swift in Sources */,
+				DB3EA8F1281B9EF600598866 /* DiscoveryCommunityViewModel+Diffable.swift in Sources */,
 				DB63F775279A997D00455B82 /* NotificationTableViewCell+ViewModel.swift in Sources */,
 				DB98EB5927B109890082E365 /* ReportSupplementaryViewController.swift in Sources */,
 				DB0617EB277EF3820030EE79 /* GradientBorderView.swift in Sources */,

Mastodon/Generated/AutoGenerateTableViewDelegate.generated.swift

@@ -1,14 +1,7 @@
 // Generated using Sourcery 1.6.1 — https://github.com/krzysztofzablocki/Sourcery
 // DO NOT EDIT
 
-
+// sourcery:inline:DiscoveryCommunityViewController.AutoGenerateTableViewDelegate
-
-
-
-
-
-
-// sourcery:inline:UserTimelineViewController.AutoGenerateTableViewDelegate
 
 // Generated using Sourcery
 // DO NOT EDIT
@@ -33,3 +26,13 @@ func tableView(_ tableView: UITableView, willPerformPreviewActionForMenuWith con
 }
 // sourcery:end
 
+
+
+
+
+
+
+
+
+
+

Mastodon/Scene/Discovery/Community/CommunityViewViewModel.swift

@@ -0,0 +1,64 @@
+//
+//  DiscoveryCommunityViewViewModel.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import os.log
+import UIKit
+import Combine
+import GameplayKit
+import CoreData
+import CoreDataStack
+import MastodonSDK
+
+final class DiscoveryCommunityViewViewModel {
+    
+    let logger = Logger(subsystem: "DiscoveryCommunityViewViewModel", category: "ViewModel")
+    
+    var disposeBag = Set<AnyCancellable>()
+    
+    // input
+    let context: AppContext
+    let viewDidAppeared = PassthroughSubject<Void, Never>()
+    let statusFetchedResultsController: StatusFetchedResultsController
+
+    // output
+    var diffableDataSource: UITableViewDiffableDataSource<StatusSection, StatusItem>?
+    private(set) lazy var stateMachine: GKStateMachine = {
+        let stateMachine = GKStateMachine(states: [
+            State.Initial(viewModel: self),
+            State.Reloading(viewModel: self),
+            State.Fail(viewModel: self),
+            State.Idle(viewModel: self),
+            State.Loading(viewModel: self),
+            State.NoMore(viewModel: self),
+        ])
+        stateMachine.enter(State.Initial.self)
+        return stateMachine
+    }()
+    
+    let didLoadLatest = PassthroughSubject<Void, Never>()
+    
+    init(context: AppContext) {
+        self.context = context
+        self.statusFetchedResultsController = StatusFetchedResultsController(
+            managedObjectContext: context.managedObjectContext,
+            domain: nil,
+            additionalTweetPredicate: nil
+        )
+        // end init
+        
+        context.authenticationService.activeMastodonAuthentication
+            .map { $0?.domain }
+            .assign(to: \.value, on: statusFetchedResultsController.domain)
+            .store(in: &disposeBag)
+    
+    }
+    
+    deinit {
+        os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s", ((#file as NSString).lastPathComponent), #line, #function)
+    }
+    
+}

Mastodon/Scene/Discovery/Community/DiscoveryCommunityViewController+DataSourceProvider.swift

@@ -0,0 +1,34 @@
+//
+//  DiscoveryCommunityViewController+DataSourceProvider.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import UIKit
+
+extension DiscoveryCommunityViewController: DataSourceProvider {
+    func item(from source: DataSourceItem.Source) async -> DataSourceItem? {
+        var _indexPath = source.indexPath
+        if _indexPath == nil, let cell = source.tableViewCell {
+            _indexPath = await self.indexPath(for: cell)
+        }
+        guard let indexPath = _indexPath else { return nil }
+        
+        guard let item = viewModel.diffableDataSource?.itemIdentifier(for: indexPath) else {
+            return nil
+        }
+        
+        switch item {
+        case .status(let record):
+            return .status(record: record)
+        default:
+            return nil
+        }
+    }
+    
+    @MainActor
+    private func indexPath(for cell: UITableViewCell) async -> IndexPath? {
+        return tableView.indexPath(for: cell)
+    }
+}

Mastodon/Scene/Discovery/Community/DiscoveryCommunityViewController.swift

@@ -0,0 +1,154 @@
+//
+//  DiscoveryCommunityViewController.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import os.log
+import UIKit
+import Combine
+import MastodonUI
+
+// Local Timeline
+final class DiscoveryCommunityViewController: UIViewController, NeedsDependency, MediaPreviewableViewController {
+    
+    let logger = Logger(subsystem: "DiscoveryCommunityViewController", category: "ViewController")
+    
+    weak var context: AppContext! { willSet { precondition(!isViewLoaded) } }
+    weak var coordinator: SceneCoordinator! { willSet { precondition(!isViewLoaded) } }
+    
+    var disposeBag = Set<AnyCancellable>()
+    var viewModel: DiscoveryCommunityViewModel!
+    
+    let mediaPreviewTransitionController = MediaPreviewTransitionController()
+
+    lazy var tableView: UITableView = {
+        let tableView = UITableView()
+        tableView.rowHeight = UITableView.automaticDimension
+        tableView.estimatedRowHeight = 100
+        tableView.separatorStyle = .none
+        tableView.backgroundColor = .clear
+        return tableView
+    }()
+    
+    let refreshControl = UIRefreshControl()
+    
+    deinit {
+        os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s", ((#file as NSString).lastPathComponent), #line, #function)
+    }
+    
+}
+
+extension DiscoveryCommunityViewController {
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        
+        view.backgroundColor = ThemeService.shared.currentTheme.value.secondarySystemBackgroundColor
+        ThemeService.shared.currentTheme
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] theme in
+                guard let self = self else { return }
+                self.view.backgroundColor = theme.secondarySystemBackgroundColor
+            }
+            .store(in: &disposeBag)
+        
+        tableView.translatesAutoresizingMaskIntoConstraints = false
+        view.addSubview(tableView)
+        NSLayoutConstraint.activate([
+            tableView.topAnchor.constraint(equalTo: view.topAnchor),
+            tableView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
+            tableView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
+            tableView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
+        ])
+        
+        tableView.refreshControl = refreshControl
+        refreshControl.addTarget(self, action: #selector(DiscoveryCommunityViewController.refreshControlValueChanged(_:)), for: .valueChanged)
+        viewModel.didLoadLatest
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in
+                guard let self = self else { return }
+                self.refreshControl.endRefreshing()
+            }
+            .store(in: &disposeBag)
+
+        tableView.delegate = self
+        viewModel.setupDiffableDataSource(
+            tableView: tableView,
+            statusTableViewCellDelegate: self
+        )
+        
+        // setup batch fetch
+        viewModel.listBatchFetchViewModel.setup(scrollView: tableView)
+        viewModel.listBatchFetchViewModel.shouldFetch
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in
+                guard let self = self else { return }
+                guard self.view.window != nil else { return }
+                self.viewModel.stateMachine.enter(DiscoveryCommunityViewModel.State.Loading.self)
+            }
+            .store(in: &disposeBag)
+    }
+    
+    override func viewWillAppear(_ animated: Bool) {
+        super.viewWillAppear(animated)
+        
+        tableView.deselectRow(with: transitionCoordinator, animated: animated)
+    }
+    
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        
+        viewModel.viewDidAppeared.send()
+    }
+    
+}
+
+extension DiscoveryCommunityViewController {
+    
+    @objc private func refreshControlValueChanged(_ sender: UIRefreshControl) {
+        if !viewModel.stateMachine.enter(DiscoveryCommunityViewModel.State.Reloading.self) {
+            refreshControl.endRefreshing()
+        }
+    }
+    
+}
+
+// MARK: - UITableViewDelegate
+extension DiscoveryCommunityViewController: UITableViewDelegate, AutoGenerateTableViewDelegate {
+    // sourcery:inline:CommunityViewController.AutoGenerateTableViewDelegate
+
+    // Generated using Sourcery
+    // DO NOT EDIT
+    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
+        aspectTableView(tableView, didSelectRowAt: indexPath)
+    }
+
+    func tableView(_ tableView: UITableView, contextMenuConfigurationForRowAt indexPath: IndexPath, point: CGPoint) -> UIContextMenuConfiguration? {
+        return aspectTableView(tableView, contextMenuConfigurationForRowAt: indexPath, point: point)
+    }
+
+    func tableView(_ tableView: UITableView, previewForHighlightingContextMenuWithConfiguration configuration: UIContextMenuConfiguration) -> UITargetedPreview? {
+        return aspectTableView(tableView, previewForHighlightingContextMenuWithConfiguration: configuration)
+    }
+
+    func tableView(_ tableView: UITableView, previewForDismissingContextMenuWithConfiguration configuration: UIContextMenuConfiguration) -> UITargetedPreview? {
+        return aspectTableView(tableView, previewForDismissingContextMenuWithConfiguration: configuration)
+    }
+
+    func tableView(_ tableView: UITableView, willPerformPreviewActionForMenuWith configuration: UIContextMenuConfiguration, animator: UIContextMenuInteractionCommitAnimating) {
+        aspectTableView(tableView, willPerformPreviewActionForMenuWith: configuration, animator: animator)
+    }
+    // sourcery:end
+}
+
+// MARK: - StatusTableViewCellDelegate
+extension DiscoveryCommunityViewController: StatusTableViewCellDelegate { }
+
+// MARK: ScrollViewContainer
+extension DiscoveryCommunityViewController: ScrollViewContainer {
+    var scrollView: UIScrollView? {
+        tableView
+    }
+}

Mastodon/Scene/Discovery/Community/DiscoveryCommunityViewModel+Diffable.swift

@@ -0,0 +1,65 @@
+//
+//  DiscoveryCommunityViewModel+Diffable.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import UIKit
+import Combine
+
+extension DiscoveryCommunityViewModel {
+    
+    func setupDiffableDataSource(
+        tableView: UITableView,
+        statusTableViewCellDelegate: StatusTableViewCellDelegate
+    ) {
+        diffableDataSource = StatusSection.diffableDataSource(
+            tableView: tableView,
+            context: context,
+            configuration: StatusSection.Configuration(
+                statusTableViewCellDelegate: statusTableViewCellDelegate,
+                timelineMiddleLoaderTableViewCellDelegate: nil,
+                filterContext: .none,
+                activeFilters: nil
+            )
+        )
+        
+        stateMachine.enter(State.Reloading.self)
+        
+        statusFetchedResultsController.$records
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] records in
+                guard let self = self else { return }
+                guard let diffableDataSource = self.diffableDataSource else { return }
+                
+                var snapshot = NSDiffableDataSourceSnapshot<StatusSection, StatusItem>()
+                snapshot.appendSections([.main])
+                
+                let items = records.map { StatusItem.status(record: $0) }
+                snapshot.appendItems(items, toSection: .main)
+                
+                if let currentState = self.stateMachine.currentState {
+                    switch currentState {
+                    case is State.Initial,
+                        is State.Reloading,
+                        is State.Loading,
+                        is State.Idle,
+                        is State.Fail:
+                        if !items.isEmpty {
+                            snapshot.appendItems([.bottomLoader], toSection: .main)
+                        }
+                    case is State.NoMore:
+                        break
+                    default:
+                        assertionFailure()
+                        break
+                    }
+                }
+            
+                diffableDataSource.applySnapshot(snapshot, animated: false)
+            }
+            .store(in: &disposeBag)
+    }
+    
+}

Mastodon/Scene/Discovery/Community/DiscoveryCommunityViewModel+State.swift

@@ -0,0 +1,206 @@
+//
+//  DiscoveryCommunityViewModel+State.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import os.log
+import Foundation
+import GameplayKit
+import MastodonSDK
+
+extension DiscoveryCommunityViewModel {
+    class State: GKState, NamingState {
+        
+        let logger = Logger(subsystem: "DiscoveryCommunityViewModel.State", category: "StateMachine")
+
+        let id = UUID()
+
+        var name: String {
+            String(describing: Self.self)
+        }
+        
+        weak var viewModel: DiscoveryCommunityViewModel?
+        
+        init(viewModel: DiscoveryCommunityViewModel) {
+            self.viewModel = viewModel
+        }
+        
+        override func didEnter(from previousState: GKState?) {
+            super.didEnter(from: previousState)
+            let previousState = previousState as? DiscoveryCommunityViewModel.State
+            logger.log(level: .debug, "\((#file as NSString).lastPathComponent, privacy: .public)[\(#line, privacy: .public)], \(#function, privacy: .public): [\(self.id.uuidString)] enter \(self.name), previous: \(previousState?.name  ?? "<nil>")")
+        }
+        
+        @MainActor
+        func enter(state: State.Type) {
+            stateMachine?.enter(state)
+        }
+        
+        deinit {
+            logger.log(level: .debug, "\((#file as NSString).lastPathComponent, privacy: .public)[\(#line, privacy: .public)], \(#function, privacy: .public): [\(self.id.uuidString)] \(self.name)")
+        }
+    }
+}
+
+extension DiscoveryCommunityViewModel.State {
+    class Initial: DiscoveryCommunityViewModel.State {
+        override func isValidNextState(_ stateClass: AnyClass) -> Bool {
+            switch stateClass {
+            case is Reloading.Type:
+                return true
+            default:
+                return false
+            }
+        }
+    }
+    
+    class Reloading: DiscoveryCommunityViewModel.State {
+        override func isValidNextState(_ stateClass: AnyClass) -> Bool {
+            switch stateClass {
+            case is Loading.Type:
+                return true
+            default:
+                return false
+            }
+        }
+        
+        override func didEnter(from previousState: GKState?) {
+            super.didEnter(from: previousState)
+            guard let _ = viewModel, let stateMachine = stateMachine else { return }
+
+            stateMachine.enter(Loading.self)
+        }
+    }
+    
+    class Fail: DiscoveryCommunityViewModel.State {
+        
+        override func isValidNextState(_ stateClass: AnyClass) -> Bool {
+            switch stateClass {
+            case is Loading.Type:
+                return true
+            default:
+                return false
+            }
+        }
+        
+        override func didEnter(from previousState: GKState?) {
+            super.didEnter(from: previousState)
+            guard let _ = viewModel, let stateMachine = stateMachine else { return }
+            
+            os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: retry loading 3s later…", ((#file as NSString).lastPathComponent), #line, #function)
+            DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
+                os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: retry loading", ((#file as NSString).lastPathComponent), #line, #function)
+                stateMachine.enter(Loading.self)
+            }
+        }
+    }
+    
+    class Idle: DiscoveryCommunityViewModel.State {
+        override func isValidNextState(_ stateClass: AnyClass) -> Bool {
+            switch stateClass {
+            case is Reloading.Type, is Loading.Type:
+                return true
+            default:
+                return false
+            }
+        }
+    }
+    
+    class Loading: DiscoveryCommunityViewModel.State {
+        
+        var maxID: String?
+
+        override func isValidNextState(_ stateClass: AnyClass) -> Bool {
+            switch stateClass {
+            case is Fail.Type:
+                return true
+            case is Idle.Type:
+                return true
+            case is NoMore.Type:
+                return true
+            default:
+                return false
+            }
+        }
+        
+        override func didEnter(from previousState: GKState?) {
+            super.didEnter(from: previousState)
+            guard let viewModel = viewModel, let stateMachine = stateMachine else { return }
+                        
+            switch previousState {
+            case is Reloading:
+                maxID = nil
+            default:
+                break
+            }
+            
+            guard let authenticationBox = viewModel.context.authenticationService.activeMastodonAuthenticationBox.value else {
+                stateMachine.enter(Fail.self)
+                return
+            }
+            
+            let maxID = self.maxID
+            let isReloading = maxID == nil
+
+            Task {
+                do {
+                    let response = try await viewModel.context.apiService.publicTimeline(
+                        query: .init(
+                            local: true,
+                            remote: nil,
+                            onlyMedia: nil,
+                            maxID: maxID,
+                            sinceID: nil,
+                            minID: nil,
+                            limit: 20
+                        ),
+                        authenticationBox: authenticationBox
+                    )
+                    
+                    let newMaxID = response.link?.maxID
+                    let hasMore = newMaxID != nil
+                    self.maxID = newMaxID
+                    
+                    var hasNewStatusesAppend = false
+                    var statusIDs = isReloading ? [] : viewModel.statusFetchedResultsController.statusIDs.value
+                    for status in response.value {
+                        guard !statusIDs.contains(status.id) else { continue }
+                        statusIDs.append(status.id)
+                        hasNewStatusesAppend = true
+                    }
+                    
+                    if hasNewStatusesAppend, hasMore {
+                        self.maxID = response.link?.maxID
+                        await enter(state: Idle.self)
+                    } else {
+                        await enter(state: NoMore.self)
+                    }
+                    viewModel.statusFetchedResultsController.statusIDs.value = statusIDs
+                    viewModel.didLoadLatest.send()
+                    
+                } catch {
+                    logger.log(level: .debug, "\((#file as NSString).lastPathComponent, privacy: .public)[\(#line, privacy: .public)], \(#function, privacy: .public): fetch user timeline fail: \(error.localizedDescription)")
+                    await enter(state: Fail.self)
+                }
+            }   // end Task
+        }   // end func
+    }
+    
+    class NoMore: DiscoveryCommunityViewModel.State {
+        override func isValidNextState(_ stateClass: AnyClass) -> Bool {
+            switch stateClass {
+            case is Reloading.Type:
+                return true
+            default:
+                return false
+            }
+        }
+        
+        override func didEnter(from previousState: GKState?) {
+            super.didEnter(from: previousState)
+            
+        }
+    }
+}

Mastodon/Scene/Discovery/Community/DiscoveryCommunityViewModel.swift

@@ -0,0 +1,65 @@
+//
+//  DiscoveryCommunityViewModel.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import os.log
+import UIKit
+import Combine
+import GameplayKit
+import CoreData
+import CoreDataStack
+import MastodonSDK
+
+final class DiscoveryCommunityViewModel {
+    
+    let logger = Logger(subsystem: "DiscoveryCommunityViewModel", category: "ViewModel")
+    
+    var disposeBag = Set<AnyCancellable>()
+    
+    // input
+    let context: AppContext
+    let viewDidAppeared = PassthroughSubject<Void, Never>()
+    let statusFetchedResultsController: StatusFetchedResultsController
+    let listBatchFetchViewModel = ListBatchFetchViewModel()
+
+    // output
+    var diffableDataSource: UITableViewDiffableDataSource<StatusSection, StatusItem>?
+    private(set) lazy var stateMachine: GKStateMachine = {
+        let stateMachine = GKStateMachine(states: [
+            State.Initial(viewModel: self),
+            State.Reloading(viewModel: self),
+            State.Fail(viewModel: self),
+            State.Idle(viewModel: self),
+            State.Loading(viewModel: self),
+            State.NoMore(viewModel: self),
+        ])
+        stateMachine.enter(State.Initial.self)
+        return stateMachine
+    }()
+    
+    let didLoadLatest = PassthroughSubject<Void, Never>()
+    
+    init(context: AppContext) {
+        self.context = context
+        self.statusFetchedResultsController = StatusFetchedResultsController(
+            managedObjectContext: context.managedObjectContext,
+            domain: nil,
+            additionalTweetPredicate: nil
+        )
+        // end init
+        
+        context.authenticationService.activeMastodonAuthentication
+            .map { $0?.domain }
+            .assign(to: \.value, on: statusFetchedResultsController.domain)
+            .store(in: &disposeBag)
+    
+    }
+    
+    deinit {
+        os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s", ((#file as NSString).lastPathComponent), #line, #function)
+    }
+    
+}

Mastodon/Scene/Discovery/Community/DiscoveryCommunityViewViewModel.swift

@@ -0,0 +1,64 @@
+//
+//  DiscoveryCommunityViewModel.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import os.log
+import UIKit
+import Combine
+import GameplayKit
+import CoreData
+import CoreDataStack
+import MastodonSDK
+
+final class DiscoveryCommunityViewModel {
+    
+    let logger = Logger(subsystem: "DiscoveryCommunityViewModel", category: "ViewModel")
+    
+    var disposeBag = Set<AnyCancellable>()
+    
+    // input
+    let context: AppContext
+    let viewDidAppeared = PassthroughSubject<Void, Never>()
+    let statusFetchedResultsController: StatusFetchedResultsController
+
+    // output
+    var diffableDataSource: UITableViewDiffableDataSource<StatusSection, StatusItem>?
+    private(set) lazy var stateMachine: GKStateMachine = {
+        let stateMachine = GKStateMachine(states: [
+            State.Initial(viewModel: self),
+            State.Reloading(viewModel: self),
+            State.Fail(viewModel: self),
+            State.Idle(viewModel: self),
+            State.Loading(viewModel: self),
+            State.NoMore(viewModel: self),
+        ])
+        stateMachine.enter(State.Initial.self)
+        return stateMachine
+    }()
+    
+    let didLoadLatest = PassthroughSubject<Void, Never>()
+    
+    init(context: AppContext) {
+        self.context = context
+        self.statusFetchedResultsController = StatusFetchedResultsController(
+            managedObjectContext: context.managedObjectContext,
+            domain: nil,
+            additionalTweetPredicate: nil
+        )
+        // end init
+        
+        context.authenticationService.activeMastodonAuthentication
+            .map { $0?.domain }
+            .assign(to: \.value, on: statusFetchedResultsController.domain)
+            .store(in: &disposeBag)
+    
+    }
+    
+    deinit {
+        os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s", ((#file as NSString).lastPathComponent), #line, #function)
+    }
+    
+}

Mastodon/Scene/Discovery/DiscoveryViewModel.swift

@@ -9,6 +9,7 @@ import UIKit
 import Combine
 import Tabman
 import Pageboy
+import MastodonLocalization
 
 final class DiscoveryViewModel {
     
@@ -19,6 +20,7 @@ final class DiscoveryViewModel {
     let discoveryPostsViewController: DiscoveryPostsViewController
     let discoveryHashtagsViewController: DiscoveryHashtagsViewController
     let discoveryNewsViewController: DiscoveryNewsViewController
+    let discoveryCommunityViewController: DiscoveryCommunityViewController
     let discoveryForYouViewController: DiscoveryForYouViewController
     
     @Published var viewControllers: [ScrollViewContainer & PageViewController]
@@ -48,6 +50,12 @@ final class DiscoveryViewModel {
             viewController.viewModel = DiscoveryNewsViewModel(context: context)
             return viewController
         }()
+        discoveryCommunityViewController = {
+            let viewController = DiscoveryCommunityViewController()
+            setupDependency(viewController)
+            viewController.viewModel = DiscoveryCommunityViewModel(context: context)
+            return viewController
+        }()
         discoveryForYouViewController = {
             let viewController = DiscoveryForYouViewController()
             setupDependency(viewController)
@@ -58,6 +66,7 @@ final class DiscoveryViewModel {
             discoveryPostsViewController,
             discoveryHashtagsViewController,
             discoveryNewsViewController,
+            discoveryCommunityViewController,
             discoveryForYouViewController,
         ]
         // end init
@@ -123,7 +132,7 @@ protocol PageViewController: UIViewController {
 
 // MARK: - PageViewController
 extension DiscoveryPostsViewController: PageViewController {
-    var tabItemTitle: String { "Posts" }
+    var tabItemTitle: String { L10n.Scene.Discovery.Tabs.posts }
     var tabItem: TMBarItemable {
         return TMBarItem(title: tabItemTitle)
     }
@@ -132,7 +141,7 @@ extension DiscoveryPostsViewController: PageViewController {
 
 // MARK: - PageViewController
 extension DiscoveryHashtagsViewController: PageViewController {
-    var tabItemTitle: String { "Hashtags" }
+    var tabItemTitle: String { L10n.Scene.Discovery.Tabs.hashtags }
     var tabItem: TMBarItemable {
 
         return TMBarItem(title: tabItemTitle)
@@ -141,7 +150,15 @@ extension DiscoveryHashtagsViewController: PageViewController {
 
 // MARK: - PageViewController
 extension DiscoveryNewsViewController: PageViewController {
-    var tabItemTitle: String { "News" }
+    var tabItemTitle: String { L10n.Scene.Discovery.Tabs.news }
+    var tabItem: TMBarItemable {
+        return TMBarItem(title: tabItemTitle)
+    }
+}
+
+// MARK: - PageViewController
+extension DiscoveryCommunityViewController: PageViewController {
+    var tabItemTitle: String { "Community" }
     var tabItem: TMBarItemable {
         return TMBarItem(title: tabItemTitle)
     }
@@ -149,7 +166,7 @@ extension DiscoveryNewsViewController: PageViewController {
 
 // MARK: - PageViewController
 extension DiscoveryForYouViewController: PageViewController {
-    var tabItemTitle: String { "For You" }
+    var tabItemTitle: String { L10n.Scene.Discovery.Tabs.forYou }
     var tabItem: TMBarItemable {
         return TMBarItem(title: tabItemTitle)
     }

Mastodon/Scene/Discovery/Hashtags/DiscoveryHashtagsViewModel.swift

@@ -73,4 +73,5 @@ extension DiscoveryHashtagsViewModel {
         hashtags = response.value.filter { !$0.name.isEmpty }
         logger.log(level: .debug, "\((#file as NSString).lastPathComponent, privacy: .public)[\(#line, privacy: .public)], \(#function, privacy: .public): fetch tags: \(response.value.count)")
     }
+    
 }

Mastodon/Scene/Discovery/Posts/DiscoveryPostsViewModel+State.swift

@@ -180,7 +180,7 @@ extension DiscoveryPostsViewModel.State {
                     }
                     viewModel.statusFetchedResultsController.statusIDs.value = statusIDs
                     viewModel.didLoadLatest.send()
-//                } catch let error as? 
+                    
                 } catch {
                     logger.log(level: .debug, "\((#file as NSString).lastPathComponent, privacy: .public)[\(#line, privacy: .public)], \(#function, privacy: .public): fetch posts fail: \(error.localizedDescription)")
                     if let error = error as? Mastodon.API.Error, error.httpResponseStatus.code == 404 {

Mastodon/Scene/Profile/Timeline/UserTimelineViewModel+State.swift

@@ -195,6 +195,12 @@ extension UserTimelineViewModel.State {
             
             // trigger data source update. otherwise, spinner always display
             viewModel.isSuspended.value = viewModel.isSuspended.value
+
+            // remove bottom loader
+            guard let diffableDataSource = viewModel.diffableDataSource else { return }
+            var snapshot = diffableDataSource.snapshot()
+            snapshot.deleteItems([.bottomLoader])
+            diffableDataSource.apply(snapshot)
         }
     }
 }

Mastodon/Service/APIService/APIService+PublicTimeline.swift

@@ -0,0 +1,52 @@
+//
+//  APIService+PublicTimeline.swift
+//  Mastodon
+//
+//  Created by MainasuK on 2022-4-29.
+//
+
+import Foundation
+import Combine
+import CoreData
+import CoreDataStack
+import CommonOSLog
+import MastodonSDK
+
+extension APIService {
+ 
+    func publicTimeline(
+        query: Mastodon.API.Timeline.PublicTimelineQuery,
+        authenticationBox: MastodonAuthenticationBox
+    ) async throws -> Mastodon.Response.Content<[Mastodon.Entity.Status]> {
+        let domain = authenticationBox.domain
+        let authorization = authenticationBox.userAuthorization
+        
+        let response = try await Mastodon.API.Timeline.public(
+            session: session,
+            domain: domain,
+            query: query,
+            authorization: authorization
+        ).singleOutput()
+        
+        let managedObjectContext = self.backgroundManagedObjectContext
+        try await managedObjectContext.performChanges {
+            let me = authenticationBox.authenticationRecord.object(in: managedObjectContext)?.user
+            for entity in response.value {
+                _ = Persistence.Status.createOrMerge(
+                    in: managedObjectContext,
+                    context: Persistence.Status.PersistContext(
+                        domain: domain,
+                        entity: entity,
+                        me: me,
+                        statusCache: nil,
+                        userCache: nil,
+                        networkDate: response.networkDate
+                    )
+                )
+            }
+        }
+        
+        return response
+    }   // end func
+    
+}

Mastodon/Service/APIService/APIService+UserTimeline.swift

@@ -48,7 +48,7 @@ extension APIService {
         try await managedObjectContext.performChanges {
             let me = authenticationBox.authenticationRecord.object(in: managedObjectContext)?.user
             for entity in response.value {
-                Persistence.Status.createOrMerge(
+                _ = Persistence.Status.createOrMerge(
                     in: managedObjectContext,
                     context: Persistence.Status.PersistContext(
                         domain: domain,

MastodonSDK/Sources/MastodonSDK/API/Mastodon+API+Timeline.swift

@@ -33,16 +33,18 @@ extension Mastodon.API.Timeline {
     ///   - session: `URLSession`
     ///   - domain: Mastodon instance domain. e.g. "example.com"
     ///   - query: `PublicTimelineQuery` with query parameters
+    ///   - authorization:  required if the instance has disabled public preview
     /// - Returns: `AnyPublisher` contains `Token` nested in the response
     public static func `public`(
         session: URLSession,
         domain: String,
-        query: PublicTimelineQuery
+        query: PublicTimelineQuery,
+        authorization: Mastodon.API.OAuth.Authorization?
     ) -> AnyPublisher<Mastodon.Response.Content<[Mastodon.Entity.Status]>, Error>  {
         let request = Mastodon.API.get(
             url: publicTimelineEndpointURL(domain: domain),
             query: query,
-            authorization: nil
+            authorization: authorization
         )
         return session.dataTaskPublisher(for: request)
             .tryMap { data, response in