element-ios/RiotSwiftUI/Modules/Room/PollHistory/PollHistoryViewModel.swift

145 lines
4.3 KiB
Swift

//
// Copyright 2021-2024 New Vector Ltd.
//
// SPDX-License-Identifier: AGPL-3.0-only
// Please see LICENSE in the repository root for full details.
//
import Combine
import SwiftUI
typealias PollHistoryViewModelType = StateStoreViewModel<PollHistoryViewState, PollHistoryViewAction>
final class PollHistoryViewModel: PollHistoryViewModelType, PollHistoryViewModelProtocol {
private let pollService: PollHistoryServiceProtocol
private var polls: [TimelinePollDetails]?
private var subcriptions: Set<AnyCancellable> = .init()
var completion: ((PollHistoryViewModelResult) -> Void)?
init(mode: PollHistoryMode, pollService: PollHistoryServiceProtocol) {
self.pollService = pollService
super.init(initialViewState: PollHistoryViewState(mode: mode))
state.canLoadMoreContent = pollService.hasNextBatch
}
// MARK: - Public
override func process(viewAction: PollHistoryViewAction) {
switch viewAction {
case .viewAppeared:
setupUpdateSubscriptions()
fetchContent()
case .segmentDidChange:
updateViewState()
case .showPollDetail(let poll):
completion?(.showPollDetail(poll: poll))
case .loadMoreContent:
fetchContent()
}
}
}
private extension PollHistoryViewModel {
func fetchContent() {
state.isLoading = true
pollService
.nextBatch()
.collect()
.sink { [weak self] completion in
self?.handleBatchEnded(completion: completion)
} receiveValue: { [weak self] polls in
self?.add(polls: polls)
}
.store(in: &subcriptions)
}
func handleBatchEnded(completion: Subscribers.Completion<Error>) {
state.isLoading = false
state.canLoadMoreContent = pollService.hasNextBatch
switch completion {
case .finished:
break
case .failure:
polls = polls ?? []
state.bindings.alertInfo = .init(id: true, title: VectorL10n.pollHistoryFetchingError)
}
updateViewState()
}
func setupUpdateSubscriptions() {
subcriptions.removeAll()
pollService
.updates
.sink { [weak self] detail in
self?.update(poll: detail)
self?.updateViewState()
}
.store(in: &subcriptions)
pollService
.fetchedUpTo
.weakAssign(to: \.state.syncedUpTo, on: self)
.store(in: &subcriptions)
pollService
.livePolls
.sink { [weak self] livePoll in
self?.add(polls: [livePoll])
self?.updateViewState()
}
.store(in: &subcriptions)
}
func update(poll: TimelinePollDetails) {
guard let pollIndex = polls?.firstIndex(where: { $0.id == poll.id }) else {
return
}
polls?[pollIndex] = poll
}
func add(polls: [TimelinePollDetails]) {
self.polls = (self.polls ?? []) + polls
}
func updateViewState() {
let renderedPolls: [TimelinePollDetails]?
switch context.mode {
case .active:
renderedPolls = polls?.filter { $0.closed == false }
case .past:
renderedPolls = polls?.filter { $0.closed == true }
}
state.polls = renderedPolls?.sorted(by: { $0.startDate > $1.startDate })
}
}
extension PollHistoryViewModel.Context {
var emptyPollsText: String {
switch (viewState.bindings.mode, viewState.canLoadMoreContent) {
case (.active, true):
return VectorL10n.pollHistoryNoActivePollPeriodText("\(syncedPastDays)")
case (.active, false):
return VectorL10n.pollHistoryNoActivePollText
case (.past, true):
return VectorL10n.pollHistoryNoPastPollPeriodText("\(syncedPastDays)")
case (.past, false):
return VectorL10n.pollHistoryNoPastPollText
}
}
var syncedPastDays: Int {
guard let days = Calendar.current.dateComponents([.day], from: viewState.syncedUpTo, to: viewState.syncStartDate).day else {
return 0
}
return max(0, days)
}
}