NetNewsWire/Evergreen/Favicons/SeekingFavicon.swift

67 lines
1.8 KiB
Swift

//
// SeekingFavicon.swift
// Evergreen
//
// Created by Brent Simmons on 11/23/17.
// Copyright © 2017 Ranchero Software. All rights reserved.
//
import Foundation
extension Notification.Name {
static let SeekingFaviconDidFindFaviconURL = Notification.Name("SeekingFaviconDidFindFaviconURLNotification")
static let SeekingFaviconDidNotFindFaviconURL = Notification.Name("SeekingFaviconDidNotFindFaviconURLNotification")
}
final class SeekingFavicon {
// At first, when looking for a favicon, we only know the homePageURL.
// The faviconURL may be specified by metadata in the home page,
// or it might be at /favicon.ico,
// or it might not exist (or be unfindable, which is the same thing).
let homePageURL: String
let defaultFaviconURL: String // /favicon.ico
var didAttemptToLookAtHomePageMetadata = false
var foundFaviconURL: String?
var shouldUseDefaultFaviconURL: Bool {
return didAttemptToLookAtHomePageMetadata && foundFaviconURL == nil
}
private static let localeForLowercasing = Locale(identifier: "en_US")
init?(homePageURL: String) {
guard let url = URL(string: homePageURL), let scheme = url.scheme, let host = url.host else {
return nil
}
self.homePageURL = homePageURL
self.defaultFaviconURL = "\(scheme)://\(host)/favicon.ico".lowercased(with: SeekingFavicon.localeForLowercasing)
findFaviconURL()
}
}
private extension SeekingFavicon {
func findFaviconURL() {
FaviconURLFinder.findFaviconURL(homePageURL) { (faviconURL) in
self.didAttemptToLookAtHomePageMetadata = true
self.foundFaviconURL = faviconURL
if let _ = faviconURL {
NotificationCenter.default.post(name: .SeekingFaviconDidFindFaviconURL, object: self)
}
else {
NotificationCenter.default.post(name: .SeekingFaviconDidNotFindFaviconURL, object: self)
}
}
}
}