first commit

node_modules/expo-image/ios/Loaders/BlurhashLoader.swift

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+@preconcurrency import SDWebImage
+import ExpoModulesCore
+
+class BlurhashLoader: NSObject, SDImageLoader {
+  typealias ImageLoaderCompletedBlock = @Sendable (UIImage?, Data?, (any Error)?, Bool) -> Void
+
+  // MARK: - SDImageLoader
+
+  func canRequestImage(for url: URL?) -> Bool {
+    return url?.scheme == "blurhash"
+  }
+
+  func requestImage(
+    with url: URL?,
+    options: SDWebImageOptions = [],
+    context: [SDWebImageContextOption: Any]?,
+    progress progressBlock: SDImageLoaderProgressBlock?,
+    completed completedBlock: ImageLoaderCompletedBlock? = nil
+  ) -> SDWebImageOperation? {
+    guard let url else {
+      let error = makeNSError(description: "URL provided to BlurhashLoader is missing")
+      completedBlock?(nil, nil, error, false)
+      return nil
+    }
+    guard let source = context?[ImageView.contextSourceKey] as? ImageSource else {
+      let error = makeNSError(description: "Image source was not provided to the context")
+      completedBlock?(nil, nil, error, false)
+      return nil
+    }
+
+    // The URI looks like this: blurhash:/WgF}G?az0fs.x[jat7xFRjNHt6s.4;oe-:RkVtkCi^Nbo|xZRjWB
+    // Which means that the `pathComponents[0]` is `/` and we need to skip it to get the hash.
+    let blurhash = url.pathComponents[1]
+    let size = CGSize(width: source.width, height: source.height)
+
+    Task(priority: .high) {
+      let image = image(fromBlurhash: blurhash, size: size)
+
+      await MainActor.run {
+        if let image {
+          completedBlock?(UIImage(cgImage: image), nil, nil, true)
+        } else {
+          let error = makeNSError(description: "Unable to generate an image from the given blurhash")
+          completedBlock?(nil, nil, error, false)
+        }
+      }
+    }
+    return nil
+  }
+
+  func shouldBlockFailedURL(with url: URL, error: Error) -> Bool {
+    // If the algorithm failed to generate an image from the url,
+    // it's not possible that next time it will work :)
+    return true
+  }
+}