mastodon-ios/Mastodon/Scene/PublicTimeline/PublicTimelineViewModel+Dif...

64 lines
2.4 KiB
Swift

//
// PublicTimelineViewModel+Diffable.swift
// Mastodon
//
// Created by sxiaojian on 2021/1/27.
//
import CoreData
import CoreDataStack
import os.log
import UIKit
extension PublicTimelineViewModel {
func setupDiffableDataSource(
for tableView: UITableView,
dependency: NeedsDependency,
timelinePostTableViewCellDelegate: TimelinePostTableViewCellDelegate,
timelineMiddleLoaderTableViewCellDelegate: TimelineMiddleLoaderTableViewCellDelegate
) {
let timestampUpdatePublisher = Timer.publish(every: 1.0, on: .main, in: .common)
.autoconnect()
.share()
.eraseToAnyPublisher()
diffableDataSource = TimelineSection.tableViewDiffableDataSource(
for: tableView,
dependency: dependency,
managedObjectContext: fetchedResultsController.managedObjectContext,
timestampUpdatePublisher: timestampUpdatePublisher,
timelinePostTableViewCellDelegate: timelinePostTableViewCellDelegate,
timelineMiddleLoaderTableViewCellDelegate: timelineMiddleLoaderTableViewCellDelegate
)
items.value = []
stateMachine.enter(PublicTimelineViewModel.State.Loading.self)
}
}
// MARK: - NSFetchedResultsControllerDelegate
extension PublicTimelineViewModel: NSFetchedResultsControllerDelegate {
func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChangeContentWith snapshot: NSDiffableDataSourceSnapshotReference) {
os_log("%{public}s[%{public}ld], %{public}s", (#file as NSString).lastPathComponent, #line, #function)
let indexes = tootIDs.value
let toots = fetchedResultsController.fetchedObjects ?? []
guard toots.count == indexes.count else { return }
let indexTootTuples: [(Int, Toot)] = toots
.compactMap { toot -> (Int, Toot)? in
guard toot.deletedAt == nil else { return nil }
return indexes.firstIndex(of: toot.id).map { index in (index, toot) }
}
.sorted { $0.0 < $1.0 }
var items = [Item]()
for tuple in indexTootTuples {
items.append(Item.toot(objectID: tuple.1.objectID))
if tootIDsWhichHasGap.contains(tuple.1.id) {
items.append(Item.publicMiddleLoader(tootID: tuple.1.id))
}
}
self.items.value = items
}
}