fix: removing accessibility permission breaks keyboard inputs

closes #269

src/logic/SystemPermissions.swift

@@ -4,12 +4,20 @@ import Cocoa
 class SystemPermissions {
     static func ensureAccessibilityCheckboxIsChecked() {
         guard #available(OSX 10.9, *) else { return }
-        if !AXIsProcessTrustedWithOptions(["AXTrustedCheckOptionPrompt": true] as CFDictionary) {
+        if !AXIsProcessTrustedWithOptions([kAXTrustedCheckOptionPrompt.takeRetainedValue(): true] as CFDictionary) {
             debugPrint("Before using this app, you need to give permission in System Preferences > Security & Privacy > Privacy > Accessibility.",
-                    "Please authorize and re-launch.",
-                    "See https://help.rescuetime.com/article/59-how-do-i-enable-accessibility-permissions-on-mac-osx",
-                    separator: "\n")
+                "Please authorize and re-launch.",
+                "See https://help.rescuetime.com/article/59-how-do-i-enable-accessibility-permissions-on-mac-osx",
+                separator: "\n")
             App.shared.terminate(self)
+        } else {
+            // if the user removes the permission while the app is running, it can break keyboard inputs
+            DistributedNotificationCenter.default().addObserver(forName: NSNotification.Name("com.apple.accessibility.api"), object: nil, queue: nil) { _ in
+                // there is a delay between the notification and the permission being actually changed
+                DispatchQueue.main.asyncAfter(deadline: .now() + 0.15) {
+                    ensureAccessibilityCheckboxIsChecked()
+                }
+            }
         }
     }
 
@@ -17,9 +25,9 @@ class SystemPermissions {
         guard #available(OSX 10.15, *) else { return }
         if SLSRequestScreenCaptureAccess() != 1 {
             debugPrint("Before using this app, you need to give permission in System Preferences > Security & Privacy > Privacy > Screen Recording.",
-                    "Please authorize and re-launch.",
-                    "See https://dropshare.zendesk.com/hc/en-us/articles/360033453434-Enabling-Screen-Recording-Permission-on-macOS-Catalina-10-15-",
-                    separator: "\n")
+                "Please authorize and re-launch.",
+                "See https://dropshare.zendesk.com/hc/en-us/articles/360033453434-Enabling-Screen-Recording-Permission-on-macOS-Catalina-10-15-",
+                separator: "\n")
             App.shared.terminate(self)
         }
     }