mastodon-ios/Mastodon/Scene/Profile/Timeline/UserTimelineViewModel+State...

202 lines
7.2 KiB
Swift

//
// UserTimelineViewModel+State.swift
// Mastodon
//
// Created by MainasuK Cirno on 2021-3-30.
//
import os.log
import Foundation
import GameplayKit
import MastodonCore
import MastodonSDK
extension UserTimelineViewModel {
class State: GKState {
let logger = Logger(subsystem: "UserTimelineViewModel.State", category: "StateMachine")
let id = UUID()
weak var viewModel: UserTimelineViewModel?
init(viewModel: UserTimelineViewModel) {
self.viewModel = viewModel
}
override func didEnter(from previousState: GKState?) {
super.didEnter(from: previousState)
let from = previousState.flatMap { String(describing: $0) } ?? "nil"
let to = String(describing: self)
logger.log(level: .debug, "\((#file as NSString).lastPathComponent, privacy: .public)[\(#line, privacy: .public)], \(#function, privacy: .public): \(from) -> \(to)")
}
@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)] \(String(describing: self))")
}
}
}
extension UserTimelineViewModel.State {
class Initial: UserTimelineViewModel.State {
override func isValidNextState(_ stateClass: AnyClass) -> Bool {
guard let viewModel = viewModel else { return false }
switch stateClass {
case is Reloading.Type:
return viewModel.userIdentifier != nil
default:
return false
}
}
}
class Reloading: UserTimelineViewModel.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 = viewModel, let stateMachine = stateMachine else { return }
// reset
viewModel.statusFetchedResultsController.statusIDs = []
stateMachine.enter(Loading.self)
}
}
class Fail: UserTimelineViewModel.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: UserTimelineViewModel.State {
override func isValidNextState(_ stateClass: AnyClass) -> Bool {
switch stateClass {
case is Reloading.Type, is Loading.Type:
return true
default:
return false
}
}
}
class Loading: UserTimelineViewModel.State {
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 }
let maxID = viewModel.statusFetchedResultsController.statusIDs.last
guard let userID = viewModel.userIdentifier?.userID, !userID.isEmpty else {
stateMachine.enter(Fail.self)
return
}
let queryFilter = viewModel.queryFilter
Task {
do {
let response = try await viewModel.context.apiService.userTimeline(
accountID: userID,
maxID: maxID,
sinceID: nil,
excludeReplies: queryFilter.excludeReplies,
excludeReblogs: queryFilter.excludeReblogs,
onlyMedia: queryFilter.onlyMedia,
authenticationBox: viewModel.authContext.mastodonAuthenticationBox
)
var hasNewStatusesAppend = false
var statusIDs = viewModel.statusFetchedResultsController.statusIDs
for status in response.value {
guard !statusIDs.contains(status.id) else { continue }
statusIDs.append(status.id)
hasNewStatusesAppend = true
}
if hasNewStatusesAppend {
await enter(state: Idle.self)
} else {
await enter(state: NoMore.self)
}
viewModel.statusFetchedResultsController.statusIDs = statusIDs
} 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: UserTimelineViewModel.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)
guard let viewModel = viewModel, let _ = stateMachine else { return }
// trigger data source update. otherwise, spinner always display
viewModel.isSuspended = viewModel.isSuspended
// remove bottom loader
guard let diffableDataSource = viewModel.diffableDataSource else { return }
var snapshot = diffableDataSource.snapshot()
snapshot.deleteItems([.bottomLoader])
diffableDataSource.apply(snapshot)
}
}
}