158 lines
4.1 KiB
Swift
158 lines
4.1 KiB
Swift
//
|
||
// FaviconDownloader.swift
|
||
// NetNewsWire
|
||
//
|
||
// Created by Brent Simmons on 11/19/17.
|
||
// Copyright © 2017 Ranchero Software. All rights reserved.
|
||
//
|
||
|
||
import Foundation
|
||
import Articles
|
||
import Account
|
||
import RSCore
|
||
|
||
extension Notification.Name {
|
||
|
||
static let FaviconDidBecomeAvailable = Notification.Name("FaviconDidBecomeAvailableNotification") // userInfo key: FaviconDownloader.UserInfoKey.faviconURL
|
||
}
|
||
|
||
final class FaviconDownloader {
|
||
|
||
private let folder: String
|
||
private let diskCache: BinaryDiskCache
|
||
private var singleFaviconDownloaderCache = [String: SingleFaviconDownloader]() // faviconURL: SingleFaviconDownloader
|
||
private var homePageToFaviconURLCache = [String: String]() //homePageURL: faviconURL
|
||
private var homePageURLsWithNoFaviconURL = Set<String>()
|
||
private let queue: DispatchQueue
|
||
|
||
struct UserInfoKey {
|
||
static let faviconURL = "faviconURL"
|
||
}
|
||
|
||
init(folder: String) {
|
||
|
||
self.folder = folder
|
||
self.diskCache = BinaryDiskCache(folder: folder)
|
||
self.queue = DispatchQueue(label: "FaviconDownloader serial queue - \(folder)")
|
||
|
||
NotificationCenter.default.addObserver(self, selector: #selector(didLoadFavicon(_:)), name: .DidLoadFavicon, object: nil)
|
||
}
|
||
|
||
// MARK: - API
|
||
|
||
func favicon(for feed: Feed) -> RSImage? {
|
||
|
||
assert(Thread.isMainThread)
|
||
|
||
if let faviconURL = feed.faviconURL {
|
||
return favicon(with: faviconURL)
|
||
}
|
||
|
||
var homePageURL = feed.homePageURL
|
||
if homePageURL == nil {
|
||
// Base homePageURL off feedURL if needed. Won’t always be accurate, but is good enough.
|
||
if let feedURL = URL(string: feed.url), let scheme = feedURL.scheme, let host = feedURL.host {
|
||
homePageURL = scheme + "://" + host + "/"
|
||
}
|
||
}
|
||
if let homePageURL = homePageURL {
|
||
return favicon(withHomePageURL: homePageURL)
|
||
}
|
||
|
||
return nil
|
||
}
|
||
|
||
func favicon(with faviconURL: String) -> RSImage? {
|
||
|
||
let downloader = faviconDownloader(withURL: faviconURL)
|
||
return downloader.image
|
||
}
|
||
|
||
func favicon(withHomePageURL homePageURL: String) -> RSImage? {
|
||
|
||
let url = homePageURL.rs_normalizedURL()
|
||
if homePageURLsWithNoFaviconURL.contains(url) {
|
||
return nil
|
||
}
|
||
|
||
if let faviconURL = homePageToFaviconURLCache[url] {
|
||
return favicon(with: faviconURL)
|
||
}
|
||
|
||
findFaviconURL(with: url) { (faviconURL) in
|
||
if let faviconURL = faviconURL {
|
||
self.homePageToFaviconURLCache[url] = faviconURL
|
||
let _ = self.favicon(with: faviconURL)
|
||
}
|
||
else {
|
||
self.homePageURLsWithNoFaviconURL.insert(url)
|
||
}
|
||
}
|
||
|
||
return nil
|
||
}
|
||
|
||
// MARK: - Notifications
|
||
|
||
@objc func didLoadFavicon(_ note: Notification) {
|
||
|
||
guard let singleFaviconDownloader = note.object as? SingleFaviconDownloader else {
|
||
return
|
||
}
|
||
guard let _ = singleFaviconDownloader.image else {
|
||
return
|
||
}
|
||
|
||
postFaviconDidBecomeAvailableNotification(singleFaviconDownloader.faviconURL)
|
||
}
|
||
}
|
||
|
||
private extension FaviconDownloader {
|
||
|
||
static let localeForLowercasing = Locale(identifier: "en_US")
|
||
|
||
func findFaviconURL(with homePageURL: String, _ completion: @escaping (String?) -> Void) {
|
||
|
||
guard let url = URL(string: homePageURL) else {
|
||
completion(nil)
|
||
return
|
||
}
|
||
|
||
FaviconURLFinder.findFaviconURL(homePageURL) { (faviconURL) in
|
||
|
||
if let faviconURL = faviconURL {
|
||
completion(faviconURL)
|
||
return
|
||
}
|
||
|
||
guard let scheme = url.scheme, let host = url.host else {
|
||
completion(nil)
|
||
return
|
||
}
|
||
|
||
let defaultFaviconURL = "\(scheme)://\(host)/favicon.ico".lowercased(with: FaviconDownloader.localeForLowercasing)
|
||
completion(defaultFaviconURL)
|
||
}
|
||
}
|
||
|
||
func faviconDownloader(withURL faviconURL: String) -> SingleFaviconDownloader {
|
||
|
||
if let downloader = singleFaviconDownloaderCache[faviconURL] {
|
||
downloader.downloadFaviconIfNeeded()
|
||
return downloader
|
||
}
|
||
|
||
let downloader = SingleFaviconDownloader(faviconURL: faviconURL, diskCache: diskCache, queue: queue)
|
||
singleFaviconDownloaderCache[faviconURL] = downloader
|
||
return downloader
|
||
}
|
||
|
||
func postFaviconDidBecomeAvailableNotification(_ faviconURL: String) {
|
||
|
||
DispatchQueue.main.async {
|
||
let userInfo: [AnyHashable: Any] = [UserInfoKey.faviconURL: faviconURL]
|
||
NotificationCenter.default.post(name: .FaviconDidBecomeAvailable, object: self, userInfo: userInfo)
|
||
}
|
||
}
|
||
}
|