Show image upload progress

damus/Models/ImageUploadModel.swift

@@ -0,0 +1,28 @@
+//
+//  ImageUploadModel.swift
+//  damus
+//
+//  Created by William Casarin on 2023-03-16.
+//
+
+import Foundation
+import UIKit
+
+
+class ImageUploadModel: NSObject, URLSessionTaskDelegate, ObservableObject {
+    @Published var progress: Double? = nil
+    
+    func start(img: UIImage, uploader: ImageUploader) async -> ImageUploadResult {
+        return await create_image_upload_request(imageToUpload: img, imageUploader: uploader, progress: self)
+    }
+    
+    func urlSession(_ session: URLSession, task: URLSessionTask, didSendBodyData bytesSent: Int64, totalBytesSent: Int64, totalBytesExpectedToSend: Int64) {
+        DispatchQueue.main.async {
+            self.progress = Double(totalBytesSent) / Double(totalBytesExpectedToSend)
+            
+            if self.progress! >= 1.0 {
+                self.progress = nil
+            }
+        }
+    }
+}