jellyflood/Shared/ViewModels/ServerTaskObserver.swift

128 lines
3.2 KiB
Swift

//
// Swiftfin is subject to the terms of the Mozilla Public
// License, v2.0. If a copy of the MPL was not distributed with this
// file, you can obtain one at https://mozilla.org/MPL/2.0/.
//
// Copyright (c) 2024 Jellyfin & Jellyfin Contributors
//
import Combine
import Foundation
import JellyfinAPI
// TODO: refactor with socket implementation
// TODO: edit triggers
final class ServerTaskObserver: ViewModel, Stateful, Identifiable {
enum Action: Equatable {
case start
case stop
case stopObserving
}
enum State: Hashable {
case error(JellyfinAPIError)
case initial
case running
}
@Published
final var state: State = .initial
@Published
private(set) var task: TaskInfo
private var progressCancellable: AnyCancellable?
private var cancelCancellable: AnyCancellable?
var id: String? { task.id }
init(task: TaskInfo) {
self.task = task
}
func respond(to action: Action) -> State {
switch action {
case .start:
if case .running = state {
return state
}
progressCancellable = Task {
do {
try await start()
await MainActor.run {
self.state = .initial
}
} catch {
await MainActor.run {
self.state = .error(.init(error.localizedDescription))
}
}
}
.asAnyCancellable()
return .running
case .stop:
progressCancellable?.cancel()
cancelCancellable?.cancel()
cancelCancellable = Task {
do {
try await stop()
await MainActor.run {
self.state = .initial
}
} catch {
await MainActor.run {
self.state = .error(.init(error.localizedDescription))
}
}
}
.asAnyCancellable()
return .initial
case .stopObserving:
progressCancellable?.cancel()
cancelCancellable?.cancel()
return .initial
}
}
private func start() async throws {
guard let id = task.id else { return }
let request = Paths.startTask(taskID: id)
try await userSession.client.send(request)
try await pollTaskProgress(id: id)
}
private func pollTaskProgress(id: String) async throws {
while true {
let request = Paths.getTask(taskID: id)
let response = try await userSession.client.send(request)
await MainActor.run {
self.task = response.value
}
guard response.value.state == .running || response.value.state == .cancelling else {
break
}
try await Task.sleep(nanoseconds: 2_000_000_000)
}
}
private func stop() async throws {
guard let id = task.id else { return }
let request = Paths.stopTask(taskID: id)
try await userSession.client.send(request)
}
}