NetNewsWire/Frameworks/Account/FeedMetadataFile.swift

98 lines
2.6 KiB
Swift

//
// FeedMetadataFile.swift
// Account
//
// Created by Maurice Parker on 9/13/19.
// Copyright © 2019 Ranchero Software, LLC. All rights reserved.
//
import Foundation
import os.log
import RSCore
final class FeedMetadataFile {
private var log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "feedMetadataFile")
private let fileURL: URL
private let account: Account
private lazy var managedFile = ManagedResourceFile(fileURL: fileURL, load: loadCallback, save: saveCallback)
init(filename: String, account: Account) {
self.fileURL = URL(fileURLWithPath: filename)
self.account = account
}
func markAsDirty() {
managedFile.markAsDirty()
}
func load() {
managedFile.load()
}
func saveIfNecessary() {
managedFile.saveIfNecessary()
}
}
private extension FeedMetadataFile {
func loadCallback() {
let errorPointer: NSErrorPointer = nil
let fileCoordinator = NSFileCoordinator(filePresenter: managedFile)
fileCoordinator.coordinate(readingItemAt: fileURL, options: [], error: errorPointer, byAccessor: { readURL in
if let fileData = try? Data(contentsOf: readURL) {
let decoder = PropertyListDecoder()
account.feedMetadata = (try? decoder.decode(Account.FeedMetadataDictionary.self, from: fileData)) ?? Account.FeedMetadataDictionary()
}
account.feedMetadata.values.forEach { $0.delegate = account }
if !account.startingUp {
account.resetFeedMetadataAndUnreadCounts()
}
})
if let error = errorPointer?.pointee {
os_log(.error, log: log, "Read from disk coordination failed: %@.", error.localizedDescription)
}
}
func saveCallback() {
guard !account.isDeleted else { return }
let feedMetadata = metadataForOnlySubscribedToFeeds()
let encoder = PropertyListEncoder()
encoder.outputFormat = .binary
let errorPointer: NSErrorPointer = nil
let fileCoordinator = NSFileCoordinator(filePresenter: managedFile)
fileCoordinator.coordinate(writingItemAt: fileURL, options: [], error: errorPointer, byAccessor: { writeURL in
do {
let data = try encoder.encode(feedMetadata)
try data.write(to: writeURL)
} catch let error as NSError {
os_log(.error, log: log, "Save to disk failed: %@.", error.localizedDescription)
}
})
if let error = errorPointer?.pointee {
os_log(.error, log: log, "Save to disk coordination failed: %@.", error.localizedDescription)
}
}
private func metadataForOnlySubscribedToFeeds() -> Account.FeedMetadataDictionary {
let feedIDs = account.idToFeedDictionary.keys
return account.feedMetadata.filter { (feedID: String, metadata: FeedMetadata) -> Bool in
return feedIDs.contains(metadata.feedID)
}
}
}