Richer notifications (#68)

SecretAgent/Notifier.swift

@@ -2,6 +2,7 @@ import Foundation
 import SecretKit
 import SecretAgentKit
 import UserNotifications
+import AppKit
 
 class Notifier {
 
@@ -14,14 +15,34 @@ class Notifier {
     func notify(accessTo secret: AnySecret, by provenance: SigningRequestProvenance) {
         let notificationCenter = UNUserNotificationCenter.current()
         let notificationContent = UNMutableNotificationContent()
-        notificationContent.title = "Signed Request"
-        notificationContent.body = "\(secret.name) was used to sign a request from \(provenance.origin.name)."
+        notificationContent.title = "Signed Request from \(provenance.origin.name)"
+        notificationContent.subtitle = secret.name
+        if let iconURL = iconURL(for: provenance), let attachment = try? UNNotificationAttachment(identifier: "icon", url: iconURL, options: nil) {
+            notificationContent.attachments = [attachment]
+        }
         let request = UNNotificationRequest(identifier: UUID().uuidString, content: notificationContent, trigger: nil)
         notificationCenter.add(request, withCompletionHandler: nil)
     }
 
 }
 
+extension Notifier {
+
+    func iconURL(for provenance: SigningRequestProvenance) -> URL? {
+        do {
+            if let app = NSRunningApplication(processIdentifier: provenance.origin.pid), let icon = app.icon?.tiffRepresentation {
+                let temporaryURL = URL(fileURLWithPath: (NSTemporaryDirectory() as NSString).appendingPathComponent("\(UUID().uuidString).png"))
+                let bitmap = NSBitmapImageRep(data: icon)
+                try bitmap?.representation(using: .png, properties: [:])?.write(to: temporaryURL)
+                return temporaryURL
+            }
+        } catch {
+        }
+        return nil
+    }
+
+}
+
 extension Notifier: SigningWitness {
 
     func speakNowOrForeverHoldYourPeace(forAccessTo secret: AnySecret, by provenance: SigningRequestProvenance) throws {