Revoke device token when user switches to local notification mode

Signed-off-by: Daniel D’Aquino <daniel@daquino.me>
Reviewed-by: William Casarin <jb55@jb55.com>

damus/Models/PushNotificationClient.swift

@@ -57,7 +57,43 @@ struct PushNotificationClient {
         return
     }
     
-    
+    func revoke_token() async throws {
+        guard let device_token else { return }
+        // Send the device token and pubkey to the server
+        let token = device_token.map { String(format: "%02.2hhx", $0) }.joined()
+        
+        Log.info("Revoking device token from server: %s", for: .push_notifications, token)
+
+        let pubkey = self.keypair.pubkey
+
+        // Send those as JSON to the server
+        let json: [String: Any] = ["deviceToken": token, "pubkey": pubkey.hex()]
+
+        // create post request
+        let url = self.settings.send_device_token_to_localhost ? Constants.DEVICE_TOKEN_REVOKER_TEST_URL : Constants.DEVICE_TOKEN_REVOKER_PRODUCTION_URL
+        let json_data = try JSONSerialization.data(withJSONObject: json)
+        
+        
+        let (data, response) = try await make_nip98_authenticated_request(
+            method: .post,
+            url: url,
+            payload: json_data,
+            payload_type: .json,
+            auth_keypair: self.keypair
+        )
+        
+        if let httpResponse = response as? HTTPURLResponse {
+            switch httpResponse.statusCode {
+                case 200:
+                    Log.info("Sent device token removal request to Damus push notification server successfully", for: .push_notifications)
+                default:
+                    Log.error("Error in sending device_token removal to Damus push notification server. HTTP status code: %d; Response: %s", for: .push_notifications, httpResponse.statusCode, String(data: data, encoding: .utf8) ?? "Unknown")
+                    throw ClientError.http_response_error(status_code: httpResponse.statusCode, response: data)
+            }
+        }
+        
+        return
+    }
 }
 
 // MARK: Helper structures