feat: app update checker

Feather/Backend/Observable/UpdateManager.swift

@@ -0,0 +1,131 @@
+//
+//  UpdateManager.swift
+//  Feather
+//
+//  Created by Dominic on 24.05.2026.
+//
+
+import AltSourceKit
+import CoreData
+import Foundation
+import NimbleJSON
+
+struct AppUpdate: Identifiable, Equatable {
+	let id: String
+	let localUUID: String
+	let localVersion: String?
+	let remoteVersion: String
+	let appName: String
+	let bundleIdentifier: String
+	let downloadURL: URL
+	let sourceURL: URL
+}
+
+@MainActor
+final class UpdateManager: ObservableObject {
+	static let shared = UpdateManager()
+
+	typealias RepositoryDataHandler = Result<ASRepository, Error>
+
+	@Published private(set) var updates: [String: AppUpdate] = [:]
+	@Published private(set) var isChecking = false
+	@Published private(set) var lastCheckedDate: Date?
+
+	private let _dataService = NBFetchService()
+
+	private init() {}
+
+	func update(for app: AppInfoPresentable) -> AppUpdate? {
+		guard let uuid = app.uuid else { return nil }
+		return updates[uuid]
+	}
+
+	func checkForUpdates(
+		sources: [AltSource],
+		localApps: [AppInfoPresentable]
+	) async {
+		guard !isChecking else { return }
+
+		isChecking = true
+		defer {
+			isChecking = false
+			lastCheckedDate = Date()
+		}
+
+		let repositories = await _fetchRepositories(from: sources)
+		updates = _findUpdates(repositories: repositories, localApps: localApps)
+	}
+
+	private func _fetchRepositories(from sources: [AltSource]) async -> [(AltSource, ASRepository)] {
+		var repositories: [(AltSource, ASRepository)] = []
+
+		for source in sources {
+			guard
+				let url = source.sourceURL,
+				let repository = await _fetchRepository(from: url)
+			else {
+				continue
+			}
+
+			repositories.append((source, repository))
+		}
+
+		return repositories
+	}
+
+	private func _fetchRepository(from url: URL) async -> ASRepository? {
+		await withCheckedContinuation { continuation in
+			_dataService.fetch(from: url) { (result: RepositoryDataHandler) in
+				switch result {
+				case .success(let repository):
+					continuation.resume(returning: repository)
+				case .failure:
+					continuation.resume(returning: nil)
+				}
+			}
+		}
+	}
+
+	private func _findUpdates(
+		repositories: [(AltSource, ASRepository)],
+		localApps: [AppInfoPresentable]
+	) -> [String: AppUpdate] {
+		var foundUpdates: [String: AppUpdate] = [:]
+
+		for localApp in localApps {
+			guard
+				let localUUID = localApp.uuid,
+				let localIdentifier = localApp.identifier
+			else {
+				continue
+			}
+
+			for (source, repository) in repositories {
+				guard
+					let sourceURL = source.sourceURL,
+					let remoteApp = repository.apps.first(where: { $0.id == localIdentifier }),
+					let remoteVersion = remoteApp.currentVersion,
+					!remoteVersion.isEmpty,
+					remoteVersion != localApp.version,
+					let downloadURL = remoteApp.currentDownloadUrl
+				else {
+					continue
+				}
+
+				foundUpdates[localUUID] = AppUpdate(
+					id: localUUID,
+					localUUID: localUUID,
+					localVersion: localApp.version,
+					remoteVersion: remoteVersion,
+					appName: remoteApp.currentName,
+					bundleIdentifier: localIdentifier,
+					downloadURL: downloadURL,
+					sourceURL: sourceURL
+				)
+				break
+			}
+		}
+
+		return foundUpdates
+	}
+}

Feather/Views/Library/LibraryCellView.swift

@@ -13,6 +13,7 @@ import NimbleViews
 struct LibraryCellView: View {
 	@Environment(\.horizontalSizeClass) private var horizontalSizeClass
 	@Environment(\.editMode) private var editMode
+	@ObservedObject private var updateManager = UpdateManager.shared
 
 	var certInfo: Date.ExpirationInfo? {
 		Storage.shared.getCertificate(from: app)?.expiration?.expirationInfo()
@@ -129,6 +130,12 @@ extension LibraryCellView {
 
 	@ViewBuilder
 	private func _contextActionsExtra(for app: AppInfoPresentable) -> some View {
+		if let update = updateManager.update(for: app) {
+			Button(.localized("Update"), systemImage: "arrow.down.circle") {
+				_startUpdateDownload(update)
+			}
+		}
+
 		if app.isSigned {
 			if let id = app.identifier {
 				Button(.localized("Open"), systemImage: "app.badge.checkmark") {
@@ -157,7 +164,17 @@ extension LibraryCellView {
 	@ViewBuilder
 	private func _buttonActions(for app: AppInfoPresentable) -> some View {
 		Group {
-			if app.isSigned {
+			if let update = updateManager.update(for: app) {
+				Button {
+					_startUpdateDownload(update)
+				} label: {
+					FRExpirationPillView(
+						title: .localized("Update"),
+						revoked: false,
+						expiration: nil
+					)
+				}
+			} else if app.isSigned {
 				Button {
 					selectedInstallAppPresenting = AnyApp(base: app)
 				} label: {
@@ -181,4 +198,11 @@ extension LibraryCellView {
 		}
 		.buttonStyle(.borderless)
 	}
+
+	private func _startUpdateDownload(_ update: AppUpdate) {
+		_ = DownloadManager.shared.startDownload(
+			from: update.downloadURL,
+			id: "FeatherManualDownload_Update_\(update.localUUID)"
+		)
+	}
 }

Feather/Views/Library/LibraryView.swift

@@ -12,6 +12,7 @@ import NimbleViews
 // MARK: - View
 struct LibraryView: View {
 	@StateObject var downloadManager = DownloadManager.shared
+	@StateObject var updateManager = UpdateManager.shared
 
 	@State private var _selectedInfoAppPresenting: AnyApp?
 	@State private var _selectedSigningAppPresenting: AnyApp?
@@ -59,6 +60,12 @@ struct LibraryView: View {
 		animation: .snappy
 	) private var _importedApps: FetchedResults<Imported>
 
+	@FetchRequest(
+		entity: AltSource.entity(),
+		sortDescriptors: [NSSortDescriptor(keyPath: \AltSource.name, ascending: true)],
+		animation: .snappy
+	) private var _sources: FetchedResults<AltSource>
+
 	// MARK: Body
 	var body: some View {
 		NBNavigationView(.localized("Library")) {
@@ -146,6 +153,18 @@ struct LibraryView: View {
 						_bulkDeleteSelectedApps()
 					}
 				} else {
+					NBToolbarButton(
+						.localized("Check for Updates"),
+						systemImage: "arrow.triangle.2.circlepath",
+						style: .icon,
+						placement: .topBarTrailing,
+						isDisabled: updateManager.isChecking
+					) {
+						Task {
+							await _checkForUpdates()
+						}
+					}
+
 					NBToolbarMenu(
 						systemImage: "plus",
 						style: .icon,
@@ -253,6 +272,14 @@ extension LibraryView {
 
 		return allApps
 	}
+
+	private func _checkForUpdates() async {
+		let localApps = _signedApps.map { $0 as AppInfoPresentable } + _importedApps.map { $0 as AppInfoPresentable }
+		await updateManager.checkForUpdates(
+			sources: Array(_sources),
+			localApps: localApps
+		)
+	}
 }
 
 // MARK: - Extension: View (Sort)