Search wip

DB/Sources/DB/Content/ContentDatabase.swift

@@ -425,6 +425,38 @@ public extension ContentDatabase {
         .eraseToAnyPublisher()
     }
 
+    func process(results: Results) -> AnyPublisher<[[CollectionItem]], Error> {
+        databaseWriter.writePublisher { db -> ([StatusInfo], [Status.Id]) in
+            for account in results.accounts {
+                try account.save(db)
+            }
+
+            for status in results.statuses {
+                try status.save(db)
+            }
+
+            let ids = results.statuses.map(\.id)
+            let statusInfos = try StatusInfo.request(
+                StatusRecord.filter(ids.contains(StatusRecord.Columns.id)))
+                .fetchAll(db)
+
+            return (statusInfos, ids)
+        }
+        .map { statusInfos, ids -> [[CollectionItem]] in
+            [
+                results.accounts.map(CollectionItem.account),
+                statusInfos
+                    .sorted { ids.firstIndex(of: $0.record.id) ?? 0 < ids.firstIndex(of: $1.record.id) ?? 0 }
+                    .map {
+                    .status(.init(info: $0),
+                            .init(showContentToggled: $0.showContentToggled,
+                                  showAttachmentsToggled: $0.showAttachmentsToggled))
+                }
+            ]
+        }
+        .eraseToAnyPublisher()
+    }
+
     func timelinePublisher(_ timeline: Timeline) -> AnyPublisher<[[CollectionItem]], Error> {
         ValueObservation.tracking(
             TimelineItemsInfo.request(TimelineRecord.filter(TimelineRecord.Columns.id == timeline.id)).fetchOne)

MastodonAPI/Sources/MastodonAPI/Endpoints/ResultsEndpoint.swift

@@ -5,7 +5,43 @@ import HTTP
 import Mastodon
 
 public enum ResultsEndpoint {
-    case search(query: String, resolve: Bool)
+    case search(Search)
+}
+
+public extension ResultsEndpoint {
+    struct Search {
+        public let query: String
+        public let type: SearchType?
+        public let excludeUnreviewed: Bool
+        public let resolve: Bool
+        public let limit: Int?
+        public let offset: Int?
+        public let following: Bool
+
+        public init(query: String,
+                    type: SearchType? = nil,
+                    excludeUnreviewed: Bool = false,
+                    resolve: Bool = false,
+                    limit: Int? = nil,
+                    offset: Int? = nil,
+                    following: Bool = false) {
+            self.query = query
+            self.type = type
+            self.excludeUnreviewed = excludeUnreviewed
+            self.resolve = resolve
+            self.limit = limit
+            self.offset = offset
+            self.following = following
+        }
+    }
+}
+
+public extension ResultsEndpoint.Search {
+    enum SearchType: String {
+        case accounts
+        case hashtags
+        case statuses
+    }
 }
 
 extension ResultsEndpoint: Endpoint {
@@ -34,13 +70,33 @@ extension ResultsEndpoint: Endpoint {
 
     public var queryParameters: [URLQueryItem] {
         switch self {
-        case let .search(query, resolve):
+        case let .search(search):
-            var params = [URLQueryItem(name: "q", value: query)]
+            var params = [URLQueryItem(name: "q", value: search.query)]
 
-            if resolve {
+            if let type = search.type {
+                params.append(.init(name: "type", value: type.rawValue))
+            }
+
+            if search.excludeUnreviewed {
+                params.append(.init(name: "exclude_unreviewed", value: "true"))
+            }
+
+            if search.resolve {
                 params.append(.init(name: "resolve", value: "true"))
             }
 
+            if let limit = search.limit {
+                params.append(.init(name: "limit", value: String(limit)))
+            }
+
+            if let offset = search.offset {
+                params.append(.init(name: "offset", value: String(offset)))
+            }
+
+            if search.following {
+                params.append(.init(name: "following", value: "true"))
+            }
+
             return params
         }
     }

Metatext.xcodeproj/project.pbxproj

@@ -74,6 +74,7 @@
 		D07EC81125B232C2006DF726 /* SystemEmoji+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D07EC81025B232C2006DF726 /* SystemEmoji+Extensions.swift */; };
 		D07EC81225B232C2006DF726 /* SystemEmoji+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D07EC81025B232C2006DF726 /* SystemEmoji+Extensions.swift */; };
 		D0849C7F25903C4900A5EBCC /* Status+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0849C7E25903C4900A5EBCC /* Status+Extensions.swift */; };
+		D087671625BAA8C0001FDD43 /* ExploreViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D087671525BAA8C0001FDD43 /* ExploreViewController.swift */; };
 		D088406D25AFBBE200BB749B /* EmojiPickerViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D088406C25AFBBE200BB749B /* EmojiPickerViewController.swift */; };
 		D088406E25AFBBE200BB749B /* EmojiPickerViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D088406C25AFBBE200BB749B /* EmojiPickerViewController.swift */; };
 		D08B8D3D253F929E00B1EBEF /* ImageViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D08B8D3C253F929E00B1EBEF /* ImageViewController.swift */; };
@@ -244,6 +245,7 @@
 		D07EC81025B232C2006DF726 /* SystemEmoji+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "SystemEmoji+Extensions.swift"; sourceTree = "<group>"; };
 		D0849C7E25903C4900A5EBCC /* Status+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Status+Extensions.swift"; sourceTree = "<group>"; };
 		D085C3BB25008DEC008A6C5E /* DB */ = {isa = PBXFileReference; lastKnownFileType = folder; path = DB; sourceTree = "<group>"; };
+		D087671525BAA8C0001FDD43 /* ExploreViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ExploreViewController.swift; sourceTree = "<group>"; };
 		D088406C25AFBBE200BB749B /* EmojiPickerViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EmojiPickerViewController.swift; sourceTree = "<group>"; };
 		D08B8D3C253F929E00B1EBEF /* ImageViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImageViewController.swift; sourceTree = "<group>"; };
 		D08B8D41253F92B600B1EBEF /* ImagePageViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImagePageViewController.swift; sourceTree = "<group>"; };
@@ -549,6 +551,7 @@
 			children = (
 				D05936CE25A8D79800754FDF /* EditAttachmentViewController.swift */,
 				D088406C25AFBBE200BB749B /* EmojiPickerViewController.swift */,
+				D087671525BAA8C0001FDD43 /* ExploreViewController.swift */,
 				D08B8D49253FC36500B1EBEF /* ImageNavigationController.swift */,
 				D08B8D41253F92B600B1EBEF /* ImagePageViewController.swift */,
 				D08B8D3C253F929E00B1EBEF /* ImageViewController.swift */,
@@ -916,6 +919,7 @@
 				D0C7D49924F7616A001EBDBB /* AddIdentityView.swift in Sources */,
 				D0FCC105259C4E61000B67DF /* NewStatusViewController.swift in Sources */,
 				D0F2D54B2581CF7D00986197 /* VisualEffectBlur.swift in Sources */,
+				D087671625BAA8C0001FDD43 /* ExploreViewController.swift in Sources */,
 				D0A7AC7325748BFF00E4E8AB /* ReportStatusView.swift in Sources */,
 				D0C7D4C324F7616A001EBDBB /* MetatextApp.swift in Sources */,
 				D0E1F583251F13EC00D45315 /* WebfingerIndicatorView.swift in Sources */,

ServiceLayer/Sources/ServiceLayer/Entities/Search.swift

@@ -0,0 +1,5 @@
+// Copyright © 2021 Metabolist. All rights reserved.
+
+import MastodonAPI
+
+public typealias Search = ResultsEndpoint.Search

ServiceLayer/Sources/ServiceLayer/Services/AccountListService.swift

@@ -34,7 +34,7 @@ public struct AccountListService {
 }
 
 extension AccountListService: CollectionService {
-    public func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error> {
+    public func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error> {
         mastodonAPIClient.pagedRequest(endpoint, maxId: maxId, minId: minId)
             .handleEvents(receiveOutput: {
                 guard let maxId = $0.info.maxId else { return }

ServiceLayer/Sources/ServiceLayer/Services/CollectionService.swift

@@ -12,7 +12,7 @@ public protocol CollectionService {
     var titleLocalizationComponents: AnyPublisher<[String], Never> { get }
     var navigationService: NavigationService { get }
     var markerTimeline: Marker.Timeline? { get }
-    func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error>
+    func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error>
 }
 
 extension CollectionService {

ServiceLayer/Sources/ServiceLayer/Services/ContextService.swift

@@ -24,7 +24,7 @@ public struct ContextService {
 }
 
 extension ContextService: CollectionService {
-    public func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error> {
+    public func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error> {
         mastodonAPIClient.request(StatusEndpoint.status(id: id))
             .flatMap(contentDatabase.insert(status:))
             .merge(with: mastodonAPIClient.request(ContextEndpoint.context(id: id))

ServiceLayer/Sources/ServiceLayer/Services/ConversationsService.swift

@@ -27,7 +27,7 @@ public struct ConversationsService {
 }
 
 extension ConversationsService: CollectionService {
-    public func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error> {
+    public func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error> {
         mastodonAPIClient.pagedRequest(ConversationsEndpoint.conversations, maxId: maxId, minId: minId)
             .handleEvents(receiveOutput: {
                 guard let maxId = $0.info.maxId else { return }

ServiceLayer/Sources/ServiceLayer/Services/ExploreService.swift

@@ -0,0 +1,23 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Combine
+import DB
+import Foundation
+import Mastodon
+import MastodonAPI
+
+public struct ExploreService {
+    private let mastodonAPIClient: MastodonAPIClient
+    private let contentDatabase: ContentDatabase
+
+    init(mastodonAPIClient: MastodonAPIClient, contentDatabase: ContentDatabase) {
+        self.mastodonAPIClient = mastodonAPIClient
+        self.contentDatabase = contentDatabase
+    }
+}
+
+public extension ExploreService {
+    func searchService() -> SearchService {
+        SearchService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
+    }
+}

ServiceLayer/Sources/ServiceLayer/Services/IdentityService.swift

@@ -249,6 +249,10 @@ public extension IdentityService {
             contentDatabase: contentDatabase)
     }
 
+    func exploreService() -> ExploreService {
+        ExploreService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
+    }
+
     func notificationsService() -> NotificationsService {
         NotificationsService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
     }

ServiceLayer/Sources/ServiceLayer/Services/NavigationService.swift

@@ -114,7 +114,7 @@ private extension NavigationService {
     func webfinger(url: URL) -> AnyPublisher<Navigation, Never> {
         let navigationSubject = PassthroughSubject<Navigation, Never>()
 
-        let request = mastodonAPIClient.request(ResultsEndpoint.search(query: url.absoluteString, resolve: true))
+        let request = mastodonAPIClient.request(ResultsEndpoint.search(.init(query: url.absoluteString, resolve: true)))
             .handleEvents(
                 receiveSubscription: { _ in navigationSubject.send(.webfingerStart) },
                 receiveCompletion: { _ in navigationSubject.send(.webfingerEnd) })

ServiceLayer/Sources/ServiceLayer/Services/NotificationsService.swift

@@ -39,7 +39,7 @@ public struct NotificationsService {
 extension NotificationsService: CollectionService {
     public var markerTimeline: Marker.Timeline? { .notifications }
 
-    public func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error> {
+    public func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error> {
         mastodonAPIClient.pagedRequest(NotificationsEndpoint.notifications, maxId: maxId, minId: minId)
             .handleEvents(receiveOutput: {
                 guard let maxId = $0.info.maxId, maxId < nextPageMaxIdSubject.value else { return }

ServiceLayer/Sources/ServiceLayer/Services/SearchService.swift

@@ -0,0 +1,38 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Combine
+import DB
+import Foundation
+import Mastodon
+import MastodonAPI
+
+public struct SearchService {
+    public let sections: AnyPublisher<[[CollectionItem]], Error>
+    public let navigationService: NavigationService
+    public let nextPageMaxId: AnyPublisher<String, Never>
+
+    private let mastodonAPIClient: MastodonAPIClient
+    private let contentDatabase: ContentDatabase
+    private let nextPageMaxIdSubject = PassthroughSubject<String, Never>()
+    private let sectionsSubject = PassthroughSubject<[[CollectionItem]], Error>()
+
+    init(mastodonAPIClient: MastodonAPIClient, contentDatabase: ContentDatabase) {
+        self.mastodonAPIClient = mastodonAPIClient
+        self.contentDatabase = contentDatabase
+        nextPageMaxId = nextPageMaxIdSubject.eraseToAnyPublisher()
+        navigationService = NavigationService(mastodonAPIClient: mastodonAPIClient, contentDatabase: contentDatabase)
+        sections = sectionsSubject.eraseToAnyPublisher()
+    }
+}
+
+extension SearchService: CollectionService {
+    public func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error> {
+        guard let search = search else { return Empty().eraseToAnyPublisher() }
+
+        return mastodonAPIClient.request(ResultsEndpoint.search(search))
+            .flatMap(contentDatabase.process(results:))
+            .handleEvents(receiveOutput: sectionsSubject.send)
+            .ignoreOutput()
+            .eraseToAnyPublisher()
+    }
+}

ServiceLayer/Sources/ServiceLayer/Services/TimelineService.swift

@@ -44,7 +44,7 @@ extension TimelineService: CollectionService {
         }
     }
 
-    public func request(maxId: String?, minId: String?) -> AnyPublisher<Never, Error> {
+    public func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error> {
         mastodonAPIClient.pagedRequest(timeline.endpoint, maxId: maxId, minId: minId)
             .handleEvents(receiveOutput: {
                 if let maxId = $0.info.maxId {

View Controllers/ExploreViewController.swift

@@ -0,0 +1,50 @@
+// Copyright © 2021 Metabolist. All rights reserved.
+
+import UIKit
+import ViewModels
+
+final class ExploreViewController: UICollectionViewController {
+    private let viewModel: ExploreViewModel
+    private let rootViewModel: RootViewModel
+    private let identification: Identification
+
+    init(viewModel: ExploreViewModel, rootViewModel: RootViewModel, identification: Identification) {
+        self.viewModel = viewModel
+        self.rootViewModel = rootViewModel
+        self.identification = identification
+
+        super.init(collectionViewLayout: UICollectionViewFlowLayout())
+
+        tabBarItem = UITabBarItem(
+            title: NSLocalizedString("main-navigation.explore", comment: ""),
+            image: UIImage(systemName: "magnifyingglass"),
+            selectedImage: nil)
+    }
+
+    @available(*, unavailable)
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+
+        navigationItem.title = NSLocalizedString("main-navigation.explore", comment: "")
+
+        let searchController = UISearchController(
+            searchResultsController: TableViewController(
+                viewModel: viewModel.searchViewModel,
+                rootViewModel: rootViewModel,
+                identification: identification,
+                parentNavigationController: navigationController))
+
+        searchController.searchResultsUpdater = self
+        navigationItem.searchController = searchController
+    }
+}
+
+extension ExploreViewController: UISearchResultsUpdating {
+    func updateSearchResults(for searchController: UISearchController) {
+        viewModel.searchViewModel.query = searchController.searchBar.text ?? ""
+    }
+}

View Controllers/MainNavigationViewController.swift

@@ -54,9 +54,15 @@ final class MainNavigationViewController: UITabBarController {
 
 private extension MainNavigationViewController {
     func setupViewControllers() {
-        var controllers: [UIViewController] = [TimelinesViewController(
+        var controllers: [UIViewController] = [
-                                                viewModel: viewModel,
+            TimelinesViewController(
-                                                rootViewModel: rootViewModel)]
+                viewModel: viewModel,
+                rootViewModel: rootViewModel),
+            ExploreViewController(
+                viewModel: viewModel.exploreViewModel,
+                rootViewModel: rootViewModel,
+                identification: viewModel.identification)
+        ]
 
         if let notificationsViewModel = viewModel.notificationsViewModel {
             let notificationsViewController = TableViewController(

View Controllers/ProfileViewController.swift

@@ -9,10 +9,18 @@ final class ProfileViewController: TableViewController {
     private let viewModel: ProfileViewModel
     private var cancellables = Set<AnyCancellable>()
 
-    required init(viewModel: ProfileViewModel, rootViewModel: RootViewModel, identification: Identification) {
+    required init(
+        viewModel: ProfileViewModel,
+        rootViewModel: RootViewModel,
+        identification: Identification,
+        parentNavigationController: UINavigationController?) {
         self.viewModel = viewModel
 
-        super.init(viewModel: viewModel, rootViewModel: rootViewModel, identification: identification)
+        super.init(
+            viewModel: viewModel,
+            rootViewModel: rootViewModel,
+            identification: identification,
+            parentNavigationController: parentNavigationController)
     }
 
     override func viewDidLoad() {

View Controllers/TableViewController.swift

@@ -21,15 +21,20 @@ class TableViewController: UITableViewController {
     private var cancellables = Set<AnyCancellable>()
     private var cellHeightCaches = [CGFloat: [CollectionItem: CGFloat]]()
     private var shouldKeepPlayingVideoAfterDismissal = false
+    private weak var parentNavigationController: UINavigationController?
 
     private lazy var dataSource: TableViewDataSource = {
         .init(tableView: tableView, viewModelProvider: viewModel.viewModel(indexPath:))
     }()
 
-    init(viewModel: CollectionViewModel, rootViewModel: RootViewModel, identification: Identification) {
+    init(viewModel: CollectionViewModel,
+         rootViewModel: RootViewModel,
+         identification: Identification,
+         parentNavigationController: UINavigationController? = nil) {
         self.viewModel = viewModel
         self.rootViewModel = rootViewModel
         self.identification = identification
+        self.parentNavigationController = parentNavigationController
 
         super.init(style: .plain)
     }
@@ -51,7 +56,7 @@ class TableViewController: UITableViewController {
             refreshControl = UIRefreshControl()
             refreshControl?.addAction(
                 UIAction { [weak self] _ in
-                    self?.viewModel.request(maxId: nil, minId: nil) },
+                    self?.viewModel.request(maxId: nil, minId: nil, search: nil) },
                 for: .valueChanged)
         }
 
@@ -69,7 +74,7 @@ class TableViewController: UITableViewController {
     override func viewWillAppear(_ animated: Bool) {
         super.viewWillAppear(animated)
 
-        viewModel.request(maxId: nil, minId: nil)
+        viewModel.request(maxId: nil, minId: nil, search: nil)
     }
 
     override func scrollViewDidScroll(_ scrollView: UIScrollView) {
@@ -104,7 +109,8 @@ class TableViewController: UITableViewController {
            let maxId = viewModel.preferLastPresentIdOverNextPageMaxId
             ? dataSource.itemIdentifier(for: indexPath)?.itemId
             : viewModel.nextPageMaxId {
-            viewModel.request(maxId: maxId, minId: nil)
+            // TODO: search offset
+            viewModel.request(maxId: maxId, minId: nil, search: nil)
         }
 
         if let loadMoreView = cell.contentView as? LoadMoreView {
@@ -336,21 +342,33 @@ private extension TableViewController {
     func handle(navigation: Navigation) {
         switch navigation {
         case let .collection(collectionService):
-            show(TableViewController(
+            let vc = TableViewController(
-                    viewModel: CollectionItemsViewModel(
+                viewModel: CollectionItemsViewModel(
-                        collectionService: collectionService,
+                    collectionService: collectionService,
-                        identification: identification),
-                    rootViewModel: rootViewModel,
                     identification: identification),
-                 sender: self)
+                rootViewModel: rootViewModel,
+                identification: identification,
+            parentNavigationController: parentNavigationController)
+
+            if let parentNavigationController = parentNavigationController {
+                parentNavigationController.pushViewController(vc, animated: true)
+            } else {
+                show(vc, sender: self)
+            }
         case let .profile(profileService):
-            show(ProfileViewController(
+            let vc = ProfileViewController(
-                    viewModel: ProfileViewModel(
+                viewModel: ProfileViewModel(
-                        profileService: profileService,
+                    profileService: profileService,
-                        identification: identification),
-                    rootViewModel: rootViewModel,
                     identification: identification),
-                 sender: self)
+                rootViewModel: rootViewModel,
+                identification: identification,
+                parentNavigationController: parentNavigationController)
+
+            if let parentNavigationController = parentNavigationController {
+                parentNavigationController.pushViewController(vc, animated: true)
+            } else {
+                show(vc, sender: self)
+            }
         case let .url(url):
             present(SFSafariViewController(url: url), animated: true)
         case .webfingerStart:

View Controllers/TimelinesViewController.swift

@@ -35,6 +35,11 @@ final class TimelinesViewController: UIPageViewController {
         if let firstViewController = timelineViewControllers.first {
             setViewControllers([firstViewController], direction: .forward, animated: false)
         }
+
+        tabBarItem = UITabBarItem(
+            title: NSLocalizedString("main-navigation.timelines", comment: ""),
+            image: UIImage(systemName: "newspaper"),
+            selectedImage: nil)
     }
 
     @available(*, unavailable)
@@ -48,11 +53,6 @@ final class TimelinesViewController: UIPageViewController {
         dataSource = self
         delegate = self
 
-        tabBarItem = UITabBarItem(
-            title: NSLocalizedString("main-navigation.timelines", comment: ""),
-            image: UIImage(systemName: "newspaper"),
-            selectedImage: nil)
-
         navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(systemName: "megaphone"), primaryAction: nil)
         navigationItem.titleView = segmentedControl
         segmentedControl.selectedSegmentIndex = 0

ViewModels/Sources/ViewModels/CollectionItemsViewModel.swift

@@ -5,7 +5,7 @@ import Foundation
 import Mastodon
 import ServiceLayer
 
-public final class CollectionItemsViewModel: ObservableObject {
+public class CollectionItemsViewModel: ObservableObject {
     @Published public var alertItem: AlertItem?
     public private(set) var nextPageMaxId: String?
 
@@ -82,7 +82,7 @@ extension CollectionItemsViewModel: CollectionViewModel {
 
     public var canRefresh: Bool { collectionService.canRefresh }
 
-    public func request(maxId: String? = nil, minId: String? = nil) {
+    public func request(maxId: String? = nil, minId: String? = nil, search: Search?) {
         let publisher: AnyPublisher<Never, Error>
 
         if let markerTimeline = collectionService.markerTimeline,
@@ -90,19 +90,22 @@ extension CollectionItemsViewModel: CollectionViewModel {
            !hasRequestedUsingMarker {
             publisher = identification.service.getMarker(markerTimeline)
                 .flatMap { [weak self] in
-                    self?.collectionService.request(maxId: $0.lastReadId, minId: nil) ?? Empty().eraseToAnyPublisher()
+                    self?.collectionService.request(maxId: $0.lastReadId, minId: nil, search: nil)
+                        ?? Empty().eraseToAnyPublisher()
                 }
                 .catch { [weak self] _ in
-                    self?.collectionService.request(maxId: nil, minId: nil) ?? Empty().eraseToAnyPublisher()
+                    self?.collectionService.request(maxId: nil, minId: nil, search: nil)
+                        ?? Empty().eraseToAnyPublisher()
                 }
                 .collect()
                 .flatMap { [weak self] _ in
-                    self?.collectionService.request(maxId: nil, minId: nil) ?? Empty().eraseToAnyPublisher()
+                    self?.collectionService.request(maxId: nil, minId: nil, search: nil)
+                        ?? Empty().eraseToAnyPublisher()
                 }
                 .eraseToAnyPublisher()
             self.hasRequestedUsingMarker = true
         } else {
-            publisher = collectionService.request(maxId: realMaxId(maxId: maxId), minId: minId)
+            publisher = collectionService.request(maxId: realMaxId(maxId: maxId), minId: minId, search: search)
         }
 
         publisher

ViewModels/Sources/ViewModels/CollectionViewModel.swift

@@ -14,7 +14,7 @@ public protocol CollectionViewModel {
     var nextPageMaxId: String? { get }
     var preferLastPresentIdOverNextPageMaxId: Bool { get }
     var canRefresh: Bool { get }
-    func request(maxId: String?, minId: String?)
+    func request(maxId: String?, minId: String?, search: Search?)
     func viewedAtTop(indexPath: IndexPath)
     func select(indexPath: IndexPath)
     func canSelect(indexPath: IndexPath) -> Bool

ViewModels/Sources/ViewModels/Entities/Search.swift

@@ -0,0 +1,5 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import ServiceLayer
+
+public typealias Search = ServiceLayer.Search

ViewModels/Sources/ViewModels/ExploreViewModel.swift

@@ -0,0 +1,19 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import ServiceLayer
+
+public final class ExploreViewModel: ObservableObject {
+    public let searchViewModel: SearchViewModel
+
+    private let exploreService: ExploreService
+    private let identification: Identification
+
+    init(service: ExploreService, identification: Identification) {
+        exploreService = service
+        self.identification = identification
+        searchViewModel = SearchViewModel(
+            searchService: exploreService.searchService(),
+            identification: identification)
+    }
+}

ViewModels/Sources/ViewModels/NavigationViewModel.swift

@@ -13,13 +13,23 @@ public final class NavigationViewModel: ObservableObject {
     @Published public var presentingSecondaryNavigation = false
     @Published public var alertItem: AlertItem?
 
+    public lazy var exploreViewModel: ExploreViewModel = {
+        let exploreViewModel = ExploreViewModel(
+            service: identification.service.exploreService(),
+            identification: identification)
+
+        // TODO: initial request
+
+        return exploreViewModel
+    }()
+
     public lazy var notificationsViewModel: CollectionViewModel? = {
         if identification.identity.authenticated {
                 let notificationsViewModel = CollectionItemsViewModel(
                     collectionService: identification.service.notificationsService(),
                     identification: identification)
 
-                notificationsViewModel.request(maxId: nil, minId: nil)
+                notificationsViewModel.request(maxId: nil, minId: nil, search: nil)
 
             return notificationsViewModel
         } else {
@@ -33,7 +43,7 @@ public final class NavigationViewModel: ObservableObject {
                     collectionService: identification.service.conversationsService(),
                     identification: identification)
 
-                conversationsViewModel.request(maxId: nil, minId: nil)
+                conversationsViewModel.request(maxId: nil, minId: nil, search: nil)
 
             return conversationsViewModel
         } else {

ViewModels/Sources/ViewModels/ProfileViewModel.swift

@@ -105,7 +105,7 @@ extension ProfileViewModel: CollectionViewModel {
 
     public var canRefresh: Bool { collectionViewModel.value.canRefresh }
 
-    public func request(maxId: String?, minId: String?) {
+    public func request(maxId: String?, minId: String?, search: Search?) {
         if case .statuses = collection, maxId == nil {
             profileService.fetchPinnedStatuses()
                 .assignErrorsToAlertItem(to: \.alertItem, on: self)
@@ -113,7 +113,7 @@ extension ProfileViewModel: CollectionViewModel {
                 .store(in: &cancellables)
         }
 
-        collectionViewModel.value.request(maxId: maxId, minId: minId)
+        collectionViewModel.value.request(maxId: maxId, minId: minId, search: nil)
     }
 
     public func viewedAtTop(indexPath: IndexPath) {

ViewModels/Sources/ViewModels/SearchViewModel.swift

@@ -0,0 +1,27 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Combine
+import Foundation
+import ServiceLayer
+
+public final class SearchViewModel: CollectionItemsViewModel {
+    @Published public var query = ""
+
+    private let searchService: SearchService
+    private var cancellables = Set<AnyCancellable>()
+
+    public init(searchService: SearchService, identification: Identification) {
+        self.searchService = searchService
+
+        super.init(collectionService: searchService, identification: identification)
+
+        $query.throttle(for: .seconds(Self.queryThrottleInterval), scheduler: DispatchQueue.global(), latest: true)
+            .sink { [weak self] in self?.request(maxId: nil, minId: nil, search: .init(query: $0, limit: Self.limit)) }
+            .store(in: &cancellables)
+    }
+}
+
+private extension SearchViewModel {
+    static let queryThrottleInterval: TimeInterval = 0.5
+    static let limit = 5
+}

Views/AccountHeaderView.swift

@@ -310,7 +310,7 @@ private extension AccountHeaderView {
             segmentedControl.insertSegment(
                 action: UIAction(title: collection.title) { [weak self] _ in
                     self?.viewModel?.collection = collection
-                    self?.viewModel?.request(maxId: nil, minId: nil)
+                    self?.viewModel?.request(maxId: nil, minId: nil, search: nil)
                 },
                 at: index,
                 animated: false)