Don't reload if there's no internet connection

Workaround for #41

Plash/AppDelegate.swift

@@ -1,10 +1,13 @@
 import Cocoa
+import Combine
 import AppCenter
 import AppCenterCrashes
 import Defaults
 
 @NSApplicationMain
 final class AppDelegate: NSObject, NSApplicationDelegate {
+	var cancellables = Set<AnyCancellable>()
+
 	let menu = SSMenu()
 	let powerSourceWatcher = PowerSourceWatcher()
 
@@ -128,6 +131,13 @@ final class AppDelegate: NSObject, NSApplicationDelegate {
 			self.setEnabledStatus()
 		}
 
+		NSWorkspace.shared.notificationCenter
+			.publisher(for: NSWorkspace.didWakeNotification)
+			.sink { _ in
+				self.loadUserURL()
+			}
+			.store(in: &cancellables)
+
 		Defaults.observe(.url, options: [.new]) { change in
 			self.resetTimer()
 			self.loadURL(change.newValue)
@@ -236,6 +246,12 @@ final class AppDelegate: NSObject, NSApplicationDelegate {
 			return
 		}
 
+		// TODO: This is just a quick fix. The proper fix is to create a new web view below the existing one (with no opacity), load the URL, if it succeeds, we fade out the old one while fading in the new one. If it fails, we discard the new web view.
+		guard Reachability.isOnlineExtensive() else {
+			webViewError = NSError.appError(message: "No internet connection.")
+			return
+		}
+
 		// TODO: Report the bug to Apple.
 		// WKWebView has a bug where it can only load a local file once. So if you load file A, load file B, and load file A again, it errors. And if you load the same file as the existing one, nothing happens. Quality engineering.
 		if url.isFileURL {

Plash/util.swift

@@ -5,6 +5,7 @@ import WebKit
 import SwiftUI
 import Combine
 import Network
+import SystemConfiguration
 import LaunchAtLogin
 import Defaults
 
@@ -2587,3 +2588,51 @@ extension URL {
 		return components.url ?? self
 	}
 }
+
+
+struct Reachability {
+	/// Checks whether we're currently online.
+	static func isOnline(host: String = "apple.com") -> Bool {
+		guard let ref = SCNetworkReachabilityCreateWithName(nil, host) else {
+			return false
+		}
+
+		var flags = SCNetworkReachabilityFlags.connectionAutomatic
+		if !SCNetworkReachabilityGetFlags(ref, &flags) {
+			return false
+		}
+
+		return flags.contains(.reachable) && !flags.contains(.connectionRequired)
+	}
+
+	/// Checks multiple sources of whether we're currently online.
+	static func isOnlineExtensive() -> Bool {
+		let hosts = [
+			"apple.com",
+			"google.com",
+			"cloudflare.com",
+			"baidu.com",
+			"yandex.ru"
+		]
+
+		return hosts.contains { isOnline(host: $0) }
+	}
+}
+
+
+extension NSError {
+	/**
+	- Parameter domainPostfix: String to append to the `domain`.
+	*/
+	static func appError(
+		message: String,
+		userInfo: [String: Any] = [:],
+		domainPostfix: String? = nil
+	) -> Self {
+		.init(
+			domain: domainPostfix != nil ? "\(App.id) - \(domainPostfix!)" : App.id,
+			code: 0,
+			userInfo: [NSLocalizedDescriptionKey: message]
+		)
+	}
+}