Filters WIP

Databases/ContentDatabase.swift

@@ -45,7 +45,7 @@ extension ContentDatabase {
         .eraseToAnyPublisher()
     }
 
-    func updateLists(_ lists: [MastodonList]) -> AnyPublisher<Never, Error> {
+    func setLists(_ lists: [MastodonList]) -> AnyPublisher<Never, Error> {
         databaseQueue.writePublisher {
             for list in lists {
                 try Timeline.list(list).save($0)
@@ -65,10 +65,34 @@ extension ContentDatabase {
 
     func deleteList(id: String) -> AnyPublisher<Never, Error> {
         databaseQueue.writePublisher(updates: Timeline.filter(Column("id") == id).deleteAll)
+            .ignoreOutput()
+            .eraseToAnyPublisher()
+    }
+
+    func setFilters(_ filters: [Filter]) -> AnyPublisher<Never, Error> {
+        databaseQueue.writePublisher {
+            for filter in filters {
+                try filter.save($0)
+            }
+
+            try Filter.filter(!filters.map(\.id).contains(Column("id"))).deleteAll($0)
+        }
         .ignoreOutput()
         .eraseToAnyPublisher()
     }
 
+    func createFilter(_ filter: Filter) -> AnyPublisher<Never, Error> {
+        databaseQueue.writePublisher(updates: filter.save)
+            .ignoreOutput()
+            .eraseToAnyPublisher()
+    }
+
+    func deleteFilter(id: String) -> AnyPublisher<Never, Error> {
+        databaseQueue.writePublisher(updates: Filter.filter(Column("id") == id).deleteAll)
+            .ignoreOutput()
+            .eraseToAnyPublisher()
+    }
+
     func statusesObservation(timeline: Timeline) -> AnyPublisher<[Status], Error> {
         ValueObservation
             .tracking(timeline.statuses
@@ -107,9 +131,16 @@ extension ContentDatabase {
         ValueObservation.tracking(Timeline.filter(!Timeline.nonLists.map(\.id).contains(Column("id")))
                                     .order(Column("listTitle").collating(.localizedCaseInsensitiveCompare).asc)
                                     .fetchAll)
-        .removeDuplicates()
+            .removeDuplicates()
-        .publisher(in: databaseQueue)
+            .publisher(in: databaseQueue)
-        .eraseToAnyPublisher()
+            .eraseToAnyPublisher()
+    }
+
+    func filtersObservation() -> AnyPublisher<[Filter], Error> {
+        ValueObservation.tracking(Filter.fetchAll)
+            .removeDuplicates()
+            .publisher(in: databaseQueue)
+            .eraseToAnyPublisher()
     }
 }
 
@@ -193,6 +224,15 @@ private extension ContentDatabase {
 
                 t.primaryKey(["timelineId", "statusId"], onConflict: .replace)
             }
+
+            try db.create(table: "filter", ifNotExists: true) { t in
+                t.column("id", .text).notNull().primaryKey(onConflict: .replace)
+                t.column("phrase", .text).notNull()
+                t.column("context", .blob).notNull()
+                t.column("expiresAt", .date)
+                t.column("irreversible", .boolean).notNull()
+                t.column("wholeWord", .boolean).notNull()
+            }
         }
 
         try migrator.migrate(writer)
@@ -297,6 +337,16 @@ private extension Timeline {
     }
 }
 
+extension Filter: TableRecord, FetchableRecord, PersistableRecord {
+    static func databaseJSONDecoder(for column: String) -> JSONDecoder {
+        MastodonDecoder()
+    }
+
+    static func databaseJSONEncoder(for column: String) -> JSONEncoder {
+        MastodonEncoder()
+    }
+}
+
 private struct TransientStatusCollectionElement: Codable, TableRecord, FetchableRecord, PersistableRecord {
     let transientStatusCollectionId: String
     let statusId: String

Development Assets/DevelopmentModels.swift

@@ -114,6 +114,14 @@ extension NotificationTypesPreferencesViewModel {
     static let development = NotificationTypesPreferencesViewModel(identityService: .development)
 }
 
+extension FiltersViewModel {
+    static let development = FiltersViewModel(identityService: .development)
+}
+
+extension EditFilterViewModel {
+    static let development = EditFilterViewModel(filter: .new, identityService: .development)
+}
+
 extension StatusListViewModel {
     static let development = StatusListViewModel(
         statusListService: IdentityService.development.service(timeline: .home))

Localizations/Localizable.strings

@@ -22,12 +22,30 @@
 "preferences.expand-media.show-all" = "Show all";
 "preferences.expand-media.hide-all" = "Hide all";
 "preferences.reading-expand-spoilers" = "Always expand content warnings";
+"preferences.filters" = "Filters";
 "preferences.notification-types" = "Notification Types";
 "preferences.notification-types.follow" = "Follow";
 "preferences.notification-types.favourite" = "Favorite";
 "preferences.notification-types.reblog" = "Reblog";
 "preferences.notification-types.mention" = "Mention";
 "preferences.notification-types.poll" = "Poll";
+"filter.add-new" = "Add New Filter";
+"filter.edit" = "Edit Filter";
+"filter.keyword-or-phrase" = "Keyword or phrase";
+"filter.never-expires" = "Never expires";
+"filter.expire-after" = "Expire after";
+"filter.contexts" = "Filter contexts";
+"filter.irreversible" = "Drop instead of hide";
+"filter.irreversible-explanation" = "Filtered posts will disappear irreversibly, even if filter is later removed";
+"filter.whole-word" = "Whole word";
+"filter.whole-word-explanation" = "When the keyword or phrase is alphanumeric only, it will only be applied if it matches the whole word";
+"filter.save-changes" = "Save Changes";
+"filter.context.home" = "Home timeline";
+"filter.context.notifications" = "Notifications";
+"filter.context.public" = "Public timelines";
+"filter.context.thread" = "Conversations";
+"filter.context.account" = "Profiles";
+"filter.context.unknown" = "Unknown context";
 "status.reblogged-by" = "%@ boosted";
 "status.pinned-post" = "Pinned post";
 "status.show-more" = "Show More";

Metatext.xcodeproj/project.pbxproj

@@ -33,6 +33,13 @@
 		D0BEB1FD24F9E4E5001B0F04 /* ListsViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB1FC24F9E4E5001B0F04 /* ListsViewModel.swift */; };
 		D0BEB1FF24F9E5BB001B0F04 /* ListsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB1FE24F9E5BB001B0F04 /* ListsView.swift */; };
 		D0BEB20124FA0220001B0F04 /* ListEndpoint.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB20024FA0220001B0F04 /* ListEndpoint.swift */; };
+		D0BEB20524FA1107001B0F04 /* FiltersView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB20424FA1107001B0F04 /* FiltersView.swift */; };
+		D0BEB20724FA1121001B0F04 /* FiltersViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB20624FA1121001B0F04 /* FiltersViewModel.swift */; };
+		D0BEB20924FA1136001B0F04 /* Filter.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB20824FA1136001B0F04 /* Filter.swift */; };
+		D0BEB20B24FA12D8001B0F04 /* FiltersEndpoint.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB20A24FA12D8001B0F04 /* FiltersEndpoint.swift */; };
+		D0BEB20D24FA193A001B0F04 /* FilterEndpoint.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB20C24FA193A001B0F04 /* FilterEndpoint.swift */; };
+		D0BEB21124FA2A91001B0F04 /* EditFilterView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB21024FA2A90001B0F04 /* EditFilterView.swift */; };
+		D0BEB21324FA2C0A001B0F04 /* EditFilterViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0BEB21224FA2C0A001B0F04 /* EditFilterViewModel.swift */; };
 		D0C7D49724F7616A001EBDBB /* IdentitiesView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D42224F76169001EBDBB /* IdentitiesView.swift */; };
 		D0C7D49824F7616A001EBDBB /* CustomEmojiText.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D42324F76169001EBDBB /* CustomEmojiText.swift */; };
 		D0C7D49924F7616A001EBDBB /* AddIdentityView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D42424F76169001EBDBB /* AddIdentityView.swift */; };
@@ -206,6 +213,13 @@
 		D0BEB1FC24F9E4E5001B0F04 /* ListsViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ListsViewModel.swift; sourceTree = "<group>"; };
 		D0BEB1FE24F9E5BB001B0F04 /* ListsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ListsView.swift; sourceTree = "<group>"; };
 		D0BEB20024FA0220001B0F04 /* ListEndpoint.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ListEndpoint.swift; sourceTree = "<group>"; };
+		D0BEB20424FA1107001B0F04 /* FiltersView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FiltersView.swift; sourceTree = "<group>"; };
+		D0BEB20624FA1121001B0F04 /* FiltersViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FiltersViewModel.swift; sourceTree = "<group>"; };
+		D0BEB20824FA1136001B0F04 /* Filter.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Filter.swift; sourceTree = "<group>"; };
+		D0BEB20A24FA12D8001B0F04 /* FiltersEndpoint.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FiltersEndpoint.swift; sourceTree = "<group>"; };
+		D0BEB20C24FA193A001B0F04 /* FilterEndpoint.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FilterEndpoint.swift; sourceTree = "<group>"; };
+		D0BEB21024FA2A90001B0F04 /* EditFilterView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EditFilterView.swift; sourceTree = "<group>"; };
+		D0BEB21224FA2C0A001B0F04 /* EditFilterViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EditFilterViewModel.swift; sourceTree = "<group>"; };
 		D0C7D41E24F76169001EBDBB /* Metatext.entitlements */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.entitlements; path = Metatext.entitlements; sourceTree = "<group>"; };
 		D0C7D41F24F76169001EBDBB /* Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		D0C7D42224F76169001EBDBB /* IdentitiesView.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = IdentitiesView.swift; sourceTree = "<group>"; };
@@ -431,6 +445,8 @@
 				D0C7D42424F76169001EBDBB /* AddIdentityView.swift */,
 				D01F41E024F8885900D55A2D /* Attachments */,
 				D0C7D42324F76169001EBDBB /* CustomEmojiText.swift */,
+				D0BEB21024FA2A90001B0F04 /* EditFilterView.swift */,
+				D0BEB20424FA1107001B0F04 /* FiltersView.swift */,
 				D0C7D42224F76169001EBDBB /* IdentitiesView.swift */,
 				D0BEB1FE24F9E5BB001B0F04 /* ListsView.swift */,
 				D0BEB1F624F9A84B001B0F04 /* LoadingTableFooterView.swift */,
@@ -474,6 +490,7 @@
 				D0C7D43A24F76169001EBDBB /* Attachment.swift */,
 				D0C7D44124F76169001EBDBB /* Card.swift */,
 				D0C7D44B24F76169001EBDBB /* Emoji.swift */,
+				D0BEB20824FA1136001B0F04 /* Filter.swift */,
 				D0C7D44224F76169001EBDBB /* HTML.swift */,
 				D0C7D43B24F76169001EBDBB /* Identity.swift */,
 				D0C7D44524F76169001EBDBB /* Instance.swift */,
@@ -517,6 +534,8 @@
 			children = (
 				D0C7D46024F76169001EBDBB /* AddIdentityViewModel.swift */,
 				D01F41DE24F8868800D55A2D /* AttachmentViewModel.swift */,
+				D0BEB21224FA2C0A001B0F04 /* EditFilterViewModel.swift */,
+				D0BEB20624FA1121001B0F04 /* FiltersViewModel.swift */,
 				D0C7D45F24F76169001EBDBB /* IdentitiesViewModel.swift */,
 				D0BEB1FC24F9E4E5001B0F04 /* ListsViewModel.swift */,
 				D0C7D45D24F76169001EBDBB /* NotificationTypesPreferencesViewModel.swift */,
@@ -591,6 +610,8 @@
 				D0C7D47F24F76169001EBDBB /* AppAuthorizationEndpoint.swift */,
 				D0C7D48324F76169001EBDBB /* ContextEndpoint.swift */,
 				D0C7D48224F76169001EBDBB /* DeletionEndpoint.swift */,
+				D0BEB20C24FA193A001B0F04 /* FilterEndpoint.swift */,
+				D0BEB20A24FA12D8001B0F04 /* FiltersEndpoint.swift */,
 				D0C7D47D24F76169001EBDBB /* InstanceEndpoint.swift */,
 				D0BEB20024FA0220001B0F04 /* ListEndpoint.swift */,
 				D0BEB1F824F9D627001B0F04 /* ListsEndpoint.swift */,
@@ -874,14 +895,17 @@
 				D0C7D4D224F7616A001EBDBB /* ContentDatabase.swift in Sources */,
 				D0C7D4F724F7616A001EBDBB /* StatusService.swift in Sources */,
 				D04FD73924D4A7B4007D572D /* AccountEndpoint+Stubbing.swift in Sources */,
+				D0BEB21324FA2C0A001B0F04 /* EditFilterViewModel.swift in Sources */,
 				D0C7D4FA24F7616A001EBDBB /* AllIdentitiesService.swift in Sources */,
 				D0C7D4CD24F7616A001EBDBB /* AddIdentityViewModel.swift in Sources */,
 				D03658D124EDD80900AC17EC /* ContextEndpoint+Stubbing.swift in Sources */,
 				D0BEB1F324F8EE8C001B0F04 /* AttachmentView.swift in Sources */,
 				D0BEB1F524F9A216001B0F04 /* Paged.swift in Sources */,
 				D0DC174A24CFF15F00A75C65 /* AppAuthorizationEndpoint+Stubbing.swift in Sources */,
+				D0BEB20D24FA193A001B0F04 /* FilterEndpoint.swift in Sources */,
 				D0C7D49A24F7616A001EBDBB /* StatusListView.swift in Sources */,
 				D01F41D924F880C400D55A2D /* TouchFallthroughTextView.swift in Sources */,
+				D0BEB20924FA1136001B0F04 /* Filter.swift in Sources */,
 				D0C7D4A524F7616A001EBDBB /* StatusListViewController.swift in Sources */,
 				D0C7D4CC24F7616A001EBDBB /* IdentitiesViewModel.swift in Sources */,
 				D0C7D4E024F7616A001EBDBB /* WebAuthSession.swift in Sources */,
@@ -952,10 +976,13 @@
 				D01F41E424F8889700D55A2D /* AttachmentsView.swift in Sources */,
 				D0C7D4AA24F7616A001EBDBB /* Attachment.swift in Sources */,
 				D0C7D4AF24F7616A001EBDBB /* PushNotification.swift in Sources */,
+				D0BEB20724FA1121001B0F04 /* FiltersViewModel.swift in Sources */,
 				D0C7D4C924F7616A001EBDBB /* TabNavigationViewModel.swift in Sources */,
+				D0BEB21124FA2A91001B0F04 /* EditFilterView.swift in Sources */,
 				D0C7D4B624F7616A001EBDBB /* ListTimeline.swift in Sources */,
 				D0C7D4E124F7616A001EBDBB /* MastodonDecoder.swift in Sources */,
 				D0C7D4B024F7616A001EBDBB /* PushSubscription.swift in Sources */,
+				D0BEB20B24FA12D8001B0F04 /* FiltersEndpoint.swift in Sources */,
 				D0C7D4C424F7616A001EBDBB /* AppDelegate.swift in Sources */,
 				D074577A24D29366004758DB /* URLSessionConfiguration+Extensions.swift in Sources */,
 				D0C7D4E424F7616A001EBDBB /* PreferencesEndpoint.swift in Sources */,
@@ -966,6 +993,7 @@
 				D0C7D4F324F7616A001EBDBB /* ContextService.swift in Sources */,
 				D0C7D4DD24F7616A001EBDBB /* CodingUserInfoKey+Extensions.swift in Sources */,
 				D0C7D4D824F7616A001EBDBB /* Publisher+Extensions.swift in Sources */,
+				D0BEB20524FA1107001B0F04 /* FiltersView.swift in Sources */,
 				D01F41D824F880C400D55A2D /* StatusTableViewCell.swift in Sources */,
 				D04FD73C24D4A83A007D572D /* InstanceEndpoint+Stubbing.swift in Sources */,
 				D0C7D4BE24F7616A001EBDBB /* Unknowable.swift in Sources */,

Model/Filter.swift

@@ -0,0 +1,56 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+
+struct Filter: Codable, Hashable, Identifiable {
+    enum Context: String, Codable, Unknowable {
+        case home
+        case notifications
+        case `public`
+        case thread
+        case account
+        case unknown
+
+        static var unknownCase: Self { .unknown }
+    }
+
+    let id: String
+    var phrase: String
+    var context: [Context]
+    var expiresAt: Date?
+    var irreversible: Bool
+    var wholeWord: Bool
+}
+
+extension Filter {
+    static let newFilterID: String = "com.metabolist.metatext.new-filter-id"
+    static let new = Self(id: newFilterID,
+                          phrase: "",
+                          context: [],
+                          expiresAt: nil,
+                          irreversible: false,
+                          wholeWord: true)
+}
+
+extension Filter.Context: Identifiable {
+    var id: Self { self }
+}
+
+extension Filter.Context {
+    var localized: String {
+        switch self {
+        case .home:
+            return NSLocalizedString("filter.context.home", comment: "")
+        case .notifications:
+            return NSLocalizedString("filter.context.notifications", comment: "")
+        case .public:
+            return NSLocalizedString("filter.context.public", comment: "")
+        case .thread:
+            return NSLocalizedString("filter.context.thread", comment: "")
+        case .account:
+            return NSLocalizedString("filter.context.account", comment: "")
+        case .unknown:
+            return NSLocalizedString("filter.context.unknown", comment: "")
+        }
+    }
+}

Networking/Mastodon API/Endpoints/DeletionEndpoint.swift

@@ -5,6 +5,7 @@ import Foundation
 enum DeletionEndpoint {
     case oauthRevoke(token: String, clientID: String, clientSecret: String)
     case list(id: String)
+    case filter(id: String)
 }
 
 extension DeletionEndpoint: MastodonEndpoint {
@@ -16,6 +17,8 @@ extension DeletionEndpoint: MastodonEndpoint {
             return ["oauth"]
         case .list:
             return defaultContext + ["lists"]
+        case .filter:
+            return defaultContext + ["filters"]
         }
     }
 
@@ -23,7 +26,7 @@ extension DeletionEndpoint: MastodonEndpoint {
         switch self {
         case .oauthRevoke:
             return ["revoke"]
-        case let .list(id):
+        case let .list(id), let .filter(id):
             return [id]
         }
     }
@@ -32,7 +35,7 @@ extension DeletionEndpoint: MastodonEndpoint {
         switch self {
         case .oauthRevoke:
             return .post
-        case .list:
+        case .list, .filter:
             return .delete
         }
     }
@@ -41,7 +44,7 @@ extension DeletionEndpoint: MastodonEndpoint {
         switch self {
         case let .oauthRevoke(token, clientID, clientSecret):
             return ["token": token, "client_id": clientID, "client_secret": clientSecret]
-        case .list:
+        case .list, .filter:
             return nil
         }
     }

Networking/Mastodon API/Endpoints/FilterEndpoint.swift

@@ -0,0 +1,94 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+
+enum FilterEndpoint {
+    case create(
+            phrase: String,
+            context: [Filter.Context],
+            irreversible: Bool,
+            wholeWord: Bool,
+            expiresIn: Date?)
+    case update(
+            id: String,
+            phrase: String,
+            context: [Filter.Context],
+            irreversible: Bool,
+            wholeWord: Bool,
+            expiresIn: Date?)
+}
+
+extension FilterEndpoint: MastodonEndpoint {
+    typealias ResultType = Filter
+
+    var context: [String] {
+        defaultContext + ["filters"]
+    }
+
+    var pathComponentsInContext: [String] {
+        switch self {
+        case .create:
+            return []
+        case let .update(id, _, _, _, _, _):
+            return [id]
+        }
+    }
+
+    var parameters: [String: Any]? {
+        switch self {
+        case let .create(phrase, context, irreversible, wholeWord, expiresIn):
+            return params(phrase: phrase,
+                          context: context,
+                          irreversible: irreversible,
+                          wholeWord: wholeWord,
+                          expiresIn: expiresIn)
+        case let .update(id, phrase, context, irreversible, wholeWord, expiresIn):
+            var params = self.params(phrase: phrase,
+                                     context: context,
+                                     irreversible: irreversible,
+                                     wholeWord: wholeWord,
+                                     expiresIn: expiresIn)
+
+            params["id"] = id
+
+            return params
+        }
+    }
+
+    var method: HTTPMethod {
+        switch self {
+        case .create:
+            return .post
+        case .update:
+            return .put
+        }
+    }
+}
+
+private extension FilterEndpoint {
+    func params(phrase: String,
+                context: [Filter.Context],
+                irreversible: Bool,
+                wholeWord: Bool,
+                expiresIn: Date?) -> [String: Any] {
+        var params: [String: Any] = [
+            "phrase": phrase,
+            "context": context.map(\.rawValue),
+            "irreversible": irreversible,
+            "whole_word": wholeWord]
+
+        if let expiresIn = expiresIn {
+            params["expires_in"] = Self.dateFormatter.string(from: expiresIn)
+        }
+
+        return params
+    }
+
+    static let dateFormatter: DateFormatter = {
+        let dateFormatter = DateFormatter()
+
+        dateFormatter.dateFormat = MastodonAPI.dateFormat
+
+        return dateFormatter
+    }()
+}

Networking/Mastodon API/Endpoints/FiltersEndpoint.swift

@@ -0,0 +1,29 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+
+enum FiltersEndpoint {
+    case filters
+}
+
+extension FiltersEndpoint: MastodonEndpoint {
+    typealias ResultType = [Filter]
+
+    var context: [String] {
+        defaultContext + ["filters"]
+    }
+
+    var pathComponentsInContext: [String] {
+        switch self {
+        case .filters:
+            return []
+        }
+    }
+
+    var method: HTTPMethod {
+        switch self {
+        case .filters:
+            return .get
+        }
+    }
+}

Services/IdentityService.swift

@@ -88,14 +88,10 @@ extension IdentityService {
 
     func refreshLists() -> AnyPublisher<Never, Error> {
         networkClient.request(ListsEndpoint.lists)
-            .flatMap(contentDatabase.updateLists(_:))
+            .flatMap(contentDatabase.setLists(_:))
             .eraseToAnyPublisher()
     }
 
-    func listsObservation() -> AnyPublisher<[Timeline], Error> {
-        contentDatabase.listsObservation()
-    }
-
     func createList(title: String) -> AnyPublisher<Never, Error> {
         networkClient.request(ListEndpoint.create(title: title))
             .flatMap(contentDatabase.createList(_:))
@@ -109,6 +105,48 @@ extension IdentityService {
             .eraseToAnyPublisher()
     }
 
+    func listsObservation() -> AnyPublisher<[Timeline], Error> {
+        contentDatabase.listsObservation()
+    }
+
+    func refreshFilters() -> AnyPublisher<Never, Error> {
+        networkClient.request(FiltersEndpoint.filters)
+            .flatMap(contentDatabase.setFilters(_:))
+            .eraseToAnyPublisher()
+    }
+
+    func createFilter(_ filter: Filter) -> AnyPublisher<Never, Error> {
+        networkClient.request(FilterEndpoint.create(phrase: filter.phrase,
+                                                    context: filter.context,
+                                                    irreversible: filter.irreversible,
+                                                    wholeWord: filter.wholeWord,
+                                                    expiresIn: filter.expiresAt))
+            .flatMap(contentDatabase.createFilter(_:))
+            .eraseToAnyPublisher()
+    }
+
+    func updateFilter(_ filter: Filter) -> AnyPublisher<Never, Error> {
+        networkClient.request(FilterEndpoint.update(id: filter.id,
+                                                    phrase: filter.phrase,
+                                                    context: filter.context,
+                                                    irreversible: filter.irreversible,
+                                                    wholeWord: filter.wholeWord,
+                                                    expiresIn: filter.expiresAt))
+            .flatMap(contentDatabase.createFilter(_:))
+            .eraseToAnyPublisher()
+    }
+
+    func deleteFilter(id: String) -> AnyPublisher<Never, Error> {
+        networkClient.request(DeletionEndpoint.filter(id: id))
+            .map { _ in id }
+            .flatMap(contentDatabase.deleteFilter(id:))
+            .eraseToAnyPublisher()
+    }
+
+    func filtersObservation() -> AnyPublisher<[Filter], Error> {
+        contentDatabase.filtersObservation()
+    }
+
     func updatePreferences(_ preferences: Identity.Preferences) -> AnyPublisher<Never, Error> {
         identityDatabase.updatePreferences(preferences, forIdentityID: identity.id)
             .zip(Just(self).first().setFailureType(to: Error.self))

View Models/EditFilterViewModel.swift

@@ -0,0 +1,57 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import Combine
+
+class EditFilterViewModel: ObservableObject {
+    @Published var filter: Filter
+    @Published var saving = false
+    @Published var alertItem: AlertItem?
+    var date: Date
+    let dateRange: ClosedRange<Date>
+    let saveCompleted: AnyPublisher<Void, Never>
+
+    private let identityService: IdentityService
+    private let saveCompletedInput = PassthroughSubject<Void, Never>()
+    private var cancellables = Set<AnyCancellable>()
+
+    init(filter: Filter, identityService: IdentityService) {
+        self.filter = filter
+        self.identityService = identityService
+        date = Calendar.autoupdatingCurrent.date(byAdding: .minute, value: 30, to: Date()) ?? Date()
+        dateRange = date...(Calendar.autoupdatingCurrent.date(byAdding: .day, value: 7, to: date) ?? Date())
+        saveCompleted = saveCompletedInput.eraseToAnyPublisher()
+    }
+}
+
+extension EditFilterViewModel {
+    var isNew: Bool { filter.id == Filter.newFilterID }
+
+    var isSaveDisabled: Bool { filter.phrase == "" || filter.context.isEmpty }
+
+    func toggleSelection(context: Filter.Context) {
+        if filter.context.contains(context) {
+            filter.context.removeAll { $0 == context }
+        } else {
+            filter.context.append(context)
+        }
+    }
+
+    func save() {
+        (isNew ? identityService.createFilter(filter) : identityService.updateFilter(filter))
+            .assignErrorsToAlertItem(to: \.alertItem, on: self)
+            .handleEvents(
+                receiveSubscription: { [weak self] _ in self?.saving = true },
+                receiveCompletion: { [weak self] in
+                    guard let self = self else { return }
+
+                    self.saving = false
+
+                    if case .finished = $0 {
+                        self.saveCompletedInput.send(())
+                    }
+                })
+            .sink { _ in }
+            .store(in: &cancellables)
+    }
+}

View Models/FiltersViewModel.swift

@@ -0,0 +1,33 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+import Combine
+
+class FiltersViewModel: ObservableObject {
+    @Published var filters = [Filter]()
+    @Published var alertItem: AlertItem?
+
+    private let identityService: IdentityService
+    private var cancellables = Set<AnyCancellable>()
+
+    init(identityService: IdentityService) {
+        self.identityService = identityService
+
+        identityService.filtersObservation()
+            .assignErrorsToAlertItem(to: \.alertItem, on: self)
+            .assign(to: &$filters)
+    }
+}
+
+extension FiltersViewModel {
+    func refreshFilters() {
+        identityService.refreshFilters()
+            .assignErrorsToAlertItem(to: \.alertItem, on: self)
+            .sink { _ in }
+            .store(in: &cancellables)
+    }
+
+    func editFilterViewModel(filter: Filter) -> EditFilterViewModel {
+        EditFilterViewModel(filter: filter, identityService: identityService)
+    }
+}

View Models/PreferencesViewModel.swift

@@ -24,4 +24,8 @@ extension PreferencesViewModel {
     func notificationTypesPreferencesViewModel() -> NotificationTypesPreferencesViewModel {
         NotificationTypesPreferencesViewModel(identityService: identityService)
     }
+
+    func filtersViewModel() -> FiltersViewModel {
+        FiltersViewModel(identityService: identityService)
+    }
 }

View Models/TabNavigationViewModel.swift

@@ -75,6 +75,11 @@ extension TabNavigationViewModel {
                 .sink { _ in }
                 .store(in: &cancellables)
 
+            identityService.refreshFilters()
+                .assignErrorsToAlertItem(to: \.alertItem, on: self)
+                .sink { _ in }
+                .store(in: &cancellables)
+
             if identity.preferences.useServerPostingReadingPreferences {
                 identityService.refreshServerPreferences()
                     .assignErrorsToAlertItem(to: \.alertItem, on: self)

Views/EditFilterView.swift

@@ -0,0 +1,90 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import SwiftUI
+
+struct EditFilterView: View {
+    @StateObject var viewModel: EditFilterViewModel
+    @Environment(\.presentationMode) var presentationMode
+
+    var body: some View {
+        Form {
+            Section(header: Text("filter.keyword-or-phrase")) {
+                TextField("filter.keyword-or-phrase", text: $viewModel.filter.phrase)
+            }
+
+            Section {
+                if viewModel.isNew || viewModel.filter.expiresAt == nil {
+                    Toggle("filter.never-expires", isOn: .init(
+                            get: { viewModel.filter.expiresAt == nil },
+                            set: {
+                                if $0 {
+                                    viewModel.filter.expiresAt = nil
+                                } else {
+                                    viewModel.filter.expiresAt = viewModel.date
+                                }
+                            }))
+                }
+
+                if viewModel.filter.expiresAt != nil {
+                    DatePicker(selection: $viewModel.date, in: viewModel.dateRange) {
+                        Text("filter.expire-after")
+                    }
+                }
+            }
+
+            Section(header: Text("filter.contexts")) {
+                ForEach(Filter.Context.allCasesExceptUnknown) { context in
+                    Toggle(context.localized, isOn: .init(
+                            get: { viewModel.filter.context.contains(context) },
+                            set: { _ in viewModel.toggleSelection(context: context) }))
+                }
+            }
+
+            Section {
+                Toggle(isOn: $viewModel.filter.irreversible, label: {
+                    VStack(alignment: .leading, spacing: 8) {
+                        Text("filter.irreversible")
+                        Text("filter.irreversible-explanation")
+                            .font(.footnote)
+                            .foregroundColor(.secondary)
+                    }
+                })
+            }
+
+            Section {
+                Toggle(isOn: $viewModel.filter.wholeWord, label: {
+                    VStack(alignment: .leading, spacing: 8) {
+                        Text("filter.whole-word")
+                        Text("filter.whole-word-explanation")
+                            .font(.footnote)
+                            .foregroundColor(.secondary)
+                    }
+                })
+            }
+        }
+        .alertItem($viewModel.alertItem)
+        .onReceive(viewModel.saveCompleted) { presentationMode.wrappedValue.dismiss() }
+        .navigationTitle(viewModel.isNew ? "filter.add-new" : "filter.edit")
+        .toolbar {
+            ToolbarItem(placement: .primaryAction) {
+                Group {
+                    if viewModel.saving {
+                        ProgressView()
+                    } else {
+                        Button(viewModel.isNew ? "add" : "filter.save-changes",
+                            action: viewModel.save)
+                            .disabled(viewModel.isSaveDisabled)
+                    }
+                }
+            }
+        }
+    }
+}
+
+#if DEBUG
+struct EditFilterView_Previews: PreviewProvider {
+    static var previews: some View {
+        EditFilterView(viewModel: .development)
+    }
+}
+#endif

Views/FiltersView.swift

@@ -0,0 +1,42 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import SwiftUI
+
+struct FiltersView: View {
+    @StateObject var viewModel: FiltersViewModel
+
+    var body: some View {
+        Form {
+            Section {
+                NavigationLink(destination: EditFilterView(
+                                viewModel: viewModel.editFilterViewModel(filter: .new))) {
+                    Label("add", systemImage: "plus.circle")
+                }
+            }
+            Section {
+                ForEach(viewModel.filters) { filter in
+                    NavigationLink(destination: EditFilterView(
+                                    viewModel: viewModel.editFilterViewModel(filter: filter))) {
+                        HStack {
+                            Text(filter.phrase)
+                            Spacer()
+                            Text(ListFormatter.localizedString(byJoining: filter.context.map(\.localized)))
+                                .foregroundColor(.secondary)
+                        }
+                    }
+                }
+            }
+        }
+        .navigationTitle("preferences.filters")
+        .alertItem($viewModel.alertItem)
+        .onAppear(perform: viewModel.refreshFilters)
+    }
+}
+
+#if DEBUG
+struct FiltersView_Previews: PreviewProvider {
+    static var previews: some View {
+        FiltersView(viewModel: .development)
+    }
+}
+#endif

Views/PreferencesView.swift

@@ -11,6 +11,9 @@ struct PreferencesView: View {
                 NavigationLink("preferences.posting-reading",
                                destination: PostingReadingPreferencesView(
                                 viewModel: viewModel.postingReadingPreferencesViewModel()))
+                NavigationLink("preferences.filters",
+                               destination: FiltersView(
+                                viewModel: viewModel.filtersViewModel()))
                 if viewModel.shouldShowNotificationTypePreferences {
                     NavigationLink("preferences.notification-types",
                                    destination: NotificationTypesPreferencesView(