refactor

handle missing asset

mobile/ios/Runner/Resolvers/Assets/AssetResolver.swift

@@ -0,0 +1,103 @@
+import Photos
+
+class AssetRequest: Request {
+  let assetId: String
+  var completion: (PHAsset?) -> Void
+
+  init(cancellationToken: CancellationToken, assetId: String, completion: @escaping (PHAsset?) -> Void) {
+    self.assetId = assetId
+    self.completion = completion
+    super.init(cancellationToken: cancellationToken)
+  }
+}
+
+class AssetResolver {
+  private static let requestQueue = DispatchQueue(label: "assets.requests", qos: .userInitiated)
+  private static let processingQueue = DispatchQueue(label: "assets.processing", qos: .userInitiated)
+
+  private static var batchTimer: DispatchWorkItem?
+  private static let batchLock = NSLock()
+  private static let batchTimeout: TimeInterval = 0.001 // 1ms
+
+  private static let fetchOptions = {
+    let fetchOptions = PHFetchOptions()
+    fetchOptions.wantsIncrementalChangeDetails = false
+    return fetchOptions
+  }()
+  private static var assetRequests = [AssetRequest]()
+  private static let assetCache = {
+    let assetCache = NSCache<NSString, PHAsset>()
+    assetCache.countLimit = 10000
+    return assetCache
+  }()
+
+  static func requestAsset(request: AssetRequest) {
+    requestQueue.async {
+      if (request.isCancelled) {
+        request.completion(nil)
+      }
+
+      if let cachedAsset = assetCache.object(forKey: request.assetId as NSString) {
+        request.completion(cachedAsset)
+        return
+      }
+
+      batchLock.lock()
+      if (request.isCancelled) {
+        batchLock.unlock()
+        request.completion(nil)
+        return
+      }
+
+      assetRequests.append(request)
+
+      batchTimer?.cancel()
+      let timer = DispatchWorkItem(block: processBatch)
+      batchTimer = timer
+      batchLock.unlock()
+
+      processingQueue.asyncAfter(deadline: .now() + batchTimeout, execute: timer)
+    }
+  }
+
+  private static func processBatch() {
+    batchLock.lock()
+    var completionMap = [String: [(PHAsset?) -> Void]]()
+    var activeAssetIds = [String]()
+    completionMap.reserveCapacity(assetRequests.count)
+    activeAssetIds.reserveCapacity(assetRequests.count)
+    for request in assetRequests {
+      if (request.isCancelled) {
+        request.completion(nil)
+        continue
+      }
+
+      if var completions = completionMap[request.assetId] {
+        completions.append(request.completion)
+      } else {
+        activeAssetIds.append(request.assetId)
+        completionMap[request.assetId] = [request.completion]
+      }
+    }
+    assetRequests.removeAll(keepingCapacity: true)
+    batchTimer = nil
+    batchLock.unlock()
+
+    guard !activeAssetIds.isEmpty else { return }
+
+    let assets = PHAsset.fetchAssets(withLocalIdentifiers: activeAssetIds, options: Self.fetchOptions)
+    assets.enumerateObjects { asset, _, _ in
+      let assetId = asset.localIdentifier
+      for completion in completionMap.removeValue(forKey: assetId)! {
+        completion(asset)
+      }
+      requestQueue.async { assetCache.setObject(asset, forKey: assetId as NSString) }
+    }
+
+    for completions in completionMap.values {
+      for completion in completions {
+        completion(nil)
+      }
+    }
+  }
+}

mobile/ios/Runner/Resolvers/Images/Thumbhash.swift

@@ -0,0 +1,225 @@
+// Copyright (c) 2023 Evan Wallace
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import Foundation
+
+// NOTE: Swift has an exponential-time type checker and compiling very simple
+// expressions can easily take many seconds, especially when expressions involve
+// numeric type constructors.
+//
+// This file deliberately breaks compound expressions up into separate variables
+// to improve compile time even though this comes at the expense of readability.
+// This is a known workaround for this deficiency in the Swift compiler.
+//
+// The following command is helpful when debugging Swift compile time issues:
+//
+//     swiftc ThumbHash.swift -Xfrontend -debug-time-function-bodies
+//
+// These optimizations brought the compile time for this file from around 2.5
+// seconds to around 250ms (10x faster).
+
+// NOTE: Swift's debug-build performance of for-in loops over numeric ranges is
+// really awful. Debug builds compile a very generic indexing iterator thing
+// that makes many nested calls for every iteration, which makes debug-build
+// performance crawl.
+//
+// This file deliberately avoids for-in loops that loop for more than a few
+// times to improve debug-build run time even though this comes at the expense
+// of readability. Similarly unsafe pointers are used instead of array getters
+// to avoid unnecessary bounds checks, which have extra overhead in debug builds.
+//
+// These optimizations brought the run time to encode and decode 10 ThumbHashes
+// in debug mode from 700ms to 70ms (10x faster).
+
+// changed signature and allocation method to avoid automatic GC
+func thumbHashToRGBA(hash: Data) -> (Int, Int, UnsafeMutableRawBufferPointer) {
+  // Read the constants
+  let h0 = UInt32(hash[0])
+  let h1 = UInt32(hash[1])
+  let h2 = UInt32(hash[2])
+  let h3 = UInt16(hash[3])
+  let h4 = UInt16(hash[4])
+  let header24 = h0 | (h1 << 8) | (h2 << 16)
+  let header16 = h3 | (h4 << 8)
+  let il_dc = header24 & 63
+  let ip_dc = (header24 >> 6) & 63
+  let iq_dc = (header24 >> 12) & 63
+  var l_dc = Float32(il_dc)
+  var p_dc = Float32(ip_dc)
+  var q_dc = Float32(iq_dc)
+  l_dc = l_dc / 63
+  p_dc = p_dc / 31.5 - 1
+  q_dc = q_dc / 31.5 - 1
+  let il_scale = (header24 >> 18) & 31
+  var l_scale = Float32(il_scale)
+  l_scale = l_scale / 31
+  let hasAlpha = (header24 >> 23) != 0
+  let ip_scale = (header16 >> 3) & 63
+  let iq_scale = (header16 >> 9) & 63
+  var p_scale = Float32(ip_scale)
+  var q_scale = Float32(iq_scale)
+  p_scale = p_scale / 63
+  q_scale = q_scale / 63
+  let isLandscape = (header16 >> 15) != 0
+  let lx16 = max(3, isLandscape ? hasAlpha ? 5 : 7 : header16 & 7)
+  let ly16 = max(3, isLandscape ? header16 & 7 : hasAlpha ? 5 : 7)
+  let lx = Int(lx16)
+  let ly = Int(ly16)
+  var a_dc = Float32(1)
+  var a_scale = Float32(1)
+  if hasAlpha {
+    let ia_dc = hash[5] & 15
+    let ia_scale = hash[5] >> 4
+    a_dc = Float32(ia_dc)
+    a_scale = Float32(ia_scale)
+    a_dc /= 15
+    a_scale /= 15
+  }
+  
+  // Read the varying factors (boost saturation by 1.25x to compensate for quantization)
+  let ac_start = hasAlpha ? 6 : 5
+  var ac_index = 0
+  let decodeChannel = { (nx: Int, ny: Int, scale: Float32) -> [Float32] in
+    var ac: [Float32] = []
+    for cy in 0 ..< ny {
+      var cx = cy > 0 ? 0 : 1
+      while cx * ny < nx * (ny - cy) {
+        let iac = (hash[ac_start + (ac_index >> 1)] >> ((ac_index & 1) << 2)) & 15;
+        var fac = Float32(iac)
+        fac = (fac / 7.5 - 1) * scale
+        ac.append(fac)
+        ac_index += 1
+        cx += 1
+      }
+    }
+    return ac
+  }
+  let l_ac = decodeChannel(lx, ly, l_scale)
+  let p_ac = decodeChannel(3, 3, p_scale * 1.25)
+  let q_ac = decodeChannel(3, 3, q_scale * 1.25)
+  let a_ac = hasAlpha ? decodeChannel(5, 5, a_scale) : []
+  
+  // Decode using the DCT into RGB
+  let ratio = thumbHashToApproximateAspectRatio(hash: hash)
+  let fw = round(ratio > 1 ? 32 : 32 * ratio)
+  let fh = round(ratio > 1 ? 32 / ratio : 32)
+  let w = Int(fw)
+  let h = Int(fh)
+  let pointer = UnsafeMutableRawBufferPointer.allocate(
+    byteCount: w * h * 4,
+    alignment: MemoryLayout<UInt8>.alignment
+  )
+  var rgba = pointer.baseAddress!.assumingMemoryBound(to: UInt8.self)
+  let cx_stop = max(lx, hasAlpha ? 5 : 3)
+  let cy_stop = max(ly, hasAlpha ? 5 : 3)
+  var fx = [Float32](repeating: 0, count: cx_stop)
+  var fy = [Float32](repeating: 0, count: cy_stop)
+  fx.withUnsafeMutableBytes { fx in
+    let fx = fx.baseAddress!.bindMemory(to: Float32.self, capacity: fx.count)
+    fy.withUnsafeMutableBytes { fy in
+      let fy = fy.baseAddress!.bindMemory(to: Float32.self, capacity: fy.count)
+      var y = 0
+      while y < h {
+        var x = 0
+        while x < w {
+          var l = l_dc
+          var p = p_dc
+          var q = q_dc
+          var a = a_dc
+          
+          // Precompute the coefficients
+          var cx = 0
+          while cx < cx_stop {
+            let fw = Float32(w)
+            let fxx = Float32(x)
+            let fcx = Float32(cx)
+            fx[cx] = cos(Float32.pi / fw * (fxx + 0.5) * fcx)
+            cx += 1
+          }
+          var cy = 0
+          while cy < cy_stop {
+            let fh = Float32(h)
+            let fyy = Float32(y)
+            let fcy = Float32(cy)
+            fy[cy] = cos(Float32.pi / fh * (fyy + 0.5) * fcy)
+            cy += 1
+          }
+          
+          // Decode L
+          var j = 0
+          cy = 0
+          while cy < ly {
+            var cx = cy > 0 ? 0 : 1
+            let fy2 = fy[cy] * 2
+            while cx * ly < lx * (ly - cy) {
+              l += l_ac[j] * fx[cx] * fy2
+              j += 1
+              cx += 1
+            }
+            cy += 1
+          }
+          
+          // Decode P and Q
+          j = 0
+          cy = 0
+          while cy < 3 {
+            var cx = cy > 0 ? 0 : 1
+            let fy2 = fy[cy] * 2
+            while cx < 3 - cy {
+              let f = fx[cx] * fy2
+              p += p_ac[j] * f
+              q += q_ac[j] * f
+              j += 1
+              cx += 1
+            }
+            cy += 1
+          }
+          
+          // Decode A
+          if hasAlpha {
+            j = 0
+            cy = 0
+            while cy < 5 {
+              var cx = cy > 0 ? 0 : 1
+              let fy2 = fy[cy] * 2
+              while cx < 5 - cy {
+                a += a_ac[j] * fx[cx] * fy2
+                j += 1
+                cx += 1
+              }
+              cy += 1
+            }
+          }
+          
+          // Convert to RGB
+          var b = l - 2 / 3 * p
+          var r = (3 * l - b + q) / 2
+          var g = r - q
+          r = max(0, 255 * min(1, r))
+          g = max(0, 255 * min(1, g))
+          b = max(0, 255 * min(1, b))
+          a = max(0, 255 * min(1, a))
+          rgba[0] = UInt8(r)
+          rgba[1] = UInt8(g)
+          rgba[2] = UInt8(b)
+          rgba[3] = UInt8(a)
+          rgba = rgba.advanced(by: 4)
+          x += 1
+        }
+        y += 1
+      }
+    }
+  }
+  return (w, h, pointer)
+}
+
+func thumbHashToApproximateAspectRatio(hash: Data) -> Float32 {
+  let header = hash[3]
+  let hasAlpha = (hash[2] & 0x80) != 0
+  let isLandscape = (hash[4] & 0x80) != 0
+  let lx = isLandscape ? hasAlpha ? 5 : 7 : header & 7
+  let ly = isLandscape ? header & 7 : hasAlpha ? 5 : 7
+  return Float32(lx) / Float32(ly)
+}

mobile/ios/Runner/Resolvers/Images/ThumbnailResolver.swift

@@ -0,0 +1,189 @@
+import CryptoKit
+import Flutter
+import MobileCoreServices
+import Photos
+
+class ThumbnailRequest: Request {
+  weak var workItem: DispatchWorkItem?
+  let completion: (Result<[String: Int64], any Error>) -> Void
+
+  init(cancellationToken: CancellationToken, completion: @escaping (Result<[String: Int64], any Error>) -> Void) {
+    self.completion = completion
+    super.init(cancellationToken: cancellationToken)
+  }
+}
+
+class ThumbnailResolver: ThumbnailApi {
+  private static let imageManager = PHImageManager.default()
+  private static let requestOptions = {
+    let requestOptions = PHImageRequestOptions()
+    requestOptions.isNetworkAccessAllowed = true
+    requestOptions.deliveryMode = .highQualityFormat
+    requestOptions.resizeMode = .fast
+    requestOptions.isSynchronous = true
+    requestOptions.version = .current
+    return requestOptions
+  }()
+
+  private static let requestQueue = DispatchQueue(label: "thumbnail.requests", qos: .userInitiated)
+  private static let cancelQueue = DispatchQueue(label: "thumbnail.cancellation", qos: .default)
+  private static let processingQueue = DispatchQueue(label: "thumbnail.processing", qos: .userInteractive, attributes: .concurrent)
+
+  private static let rgbColorSpace = CGColorSpaceCreateDeviceRGB()
+  private static let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedLast.rawValue).rawValue
+  private static var requests = [Int64: ThumbnailRequest]()
+  private static let cancelledResult = Result<[String: Int64], any Error>.success([:])
+  private static let thumbnailConcurrencySemaphore = DispatchSemaphore(value: ProcessInfo.processInfo.activeProcessorCount / 2 + 1)
+  private static let activitySemaphore = DispatchSemaphore(value: 1)
+
+  private static let willResignActiveObserver = NotificationCenter.default.addObserver(
+    forName: UIApplication.willResignActiveNotification,
+    object: nil,
+    queue: .main
+  ) { _ in
+    processingQueue.suspend()
+    activitySemaphore.wait()
+  }
+  private static let didBecomeActiveObserver = NotificationCenter.default.addObserver(
+    forName: UIApplication.didBecomeActiveNotification,
+    object: nil,
+    queue: .main
+  ) { _ in
+    processingQueue.resume()
+    activitySemaphore.signal()
+  }
+
+  func getThumbhash(thumbhash: String, completion: @escaping (Result<[String : Int64], any Error>) -> Void) {
+    Self.processingQueue.async {
+      guard let data = Data(base64Encoded: thumbhash)
+      else { return completion(.failure(PigeonError(code: "", message: "Invalid base64 string: \(thumbhash)", details: nil)))}
+
+      let (width, height, pointer) = thumbHashToRGBA(hash: data)
+      self.waitForActiveState()
+      completion(.success(["pointer": Int64(Int(bitPattern: pointer.baseAddress)), "width": Int64(width), "height": Int64(height)]))
+    }
+  }
+
+  func requestImage(assetId: String, requestId: Int64, width: Int64, height: Int64, isVideo: Bool, completion: @escaping (Result<[String: Int64], any Error>) -> Void) {
+    let cancellationToken = CancellationToken()
+    let thumbnailRequest = ThumbnailRequest(cancellationToken: cancellationToken, completion: completion)
+    AssetResolver.requestAsset(request: AssetRequest(cancellationToken: cancellationToken, assetId: assetId) { asset in
+      let item = DispatchWorkItem {
+        if cancellationToken.isCancelled {
+          return completion(Self.cancelledResult)
+        }
+
+        guard let asset = asset else {
+          if cancellationToken.isCancelled {
+            return completion(Self.cancelledResult)
+          }
+          Self.removeRequest(requestId: requestId)
+          completion(.failure(PigeonError(code: "", message: "Could not get asset data for \(assetId)", details: nil)))
+          return
+        }
+
+        Self.thumbnailConcurrencySemaphore.wait()
+        defer { Self.thumbnailConcurrencySemaphore.signal() }
+
+        if cancellationToken.isCancelled {
+          return completion(Self.cancelledResult)
+        }
+
+        var image: UIImage?
+        Self.imageManager.requestImage(
+          for: asset,
+          targetSize: width > 0 && height > 0 ? CGSize(width: Double(width), height: Double(height)) : PHImageManagerMaximumSize,
+          contentMode: .aspectFill,
+          options: Self.requestOptions,
+          resultHandler: { (_image, info) -> Void in
+            image = _image
+          }
+        )
+
+        if cancellationToken.isCancelled {
+          return completion(Self.cancelledResult)
+        }
+
+        guard let image = image,
+              let cgImage = image.cgImage else {
+          Self.removeRequest(requestId: requestId)
+          return completion(.failure(PigeonError(code: "", message: "Could not get pixel data for \(assetId)", details: nil)))
+        }
+
+        let pointer = UnsafeMutableRawPointer.allocate(
+          byteCount: Int(cgImage.width) * Int(cgImage.height) * 4,
+          alignment: MemoryLayout<UInt8>.alignment
+        )
+
+        if cancellationToken.isCancelled {
+          pointer.deallocate()
+          return completion(Self.cancelledResult)
+        }
+
+        guard let context = CGContext(
+          data: pointer,
+          width: cgImage.width,
+          height: cgImage.height,
+          bitsPerComponent: 8,
+          bytesPerRow: cgImage.width * 4,
+          space: Self.rgbColorSpace,
+          bitmapInfo: Self.bitmapInfo
+        ) else {
+          pointer.deallocate()
+          Self.removeRequest(requestId: requestId)
+          return completion(.failure(PigeonError(code: "", message: "Could not create context for \(assetId)", details: nil)))
+        }
+
+        if cancellationToken.isCancelled {
+          pointer.deallocate()
+          return completion(Self.cancelledResult)
+        }
+
+        context.interpolationQuality = .none
+        context.draw(cgImage, in: CGRect(x: 0, y: 0, width: cgImage.width, height: cgImage.height))
+
+        if cancellationToken.isCancelled {
+          pointer.deallocate()
+          return completion(Self.cancelledResult)
+        }
+
+        self.waitForActiveState()
+        completion(.success(["pointer": Int64(Int(bitPattern: pointer)), "width": Int64(cgImage.width), "height": Int64(cgImage.height)]))
+        Self.removeRequest(requestId: requestId)
+      }
+      thumbnailRequest.workItem = item
+      Self.processingQueue.async(execute: item)
+    })
+
+    Self.addRequest(requestId: requestId, request: thumbnailRequest)
+  }
+
+  func cancelImageRequest(requestId: Int64) {
+    Self.cancelRequest(requestId: requestId)
+  }
+
+  private static func addRequest(requestId: Int64, request: ThumbnailRequest) -> Void {
+    requestQueue.sync { requests[requestId] = request }
+  }
+
+  private static func removeRequest(requestId: Int64) -> Void {
+    requestQueue.sync { requests[requestId] = nil }
+  }
+
+  private static func cancelRequest(requestId: Int64) -> Void {
+    requestQueue.async {
+      guard let request = requests.removeValue(forKey: requestId) else { return }
+      request.isCancelled = true
+      guard let item = request.workItem else { return }
+      item.cancel()
+      if item.isCancelled {
+        cancelQueue.async { request.completion(Self.cancelledResult) }
+      }
+    }
+  }
+
+  func waitForActiveState() {
+    Self.activitySemaphore.wait()
+    Self.activitySemaphore.signal()
+  }
+}

mobile/ios/Runner/Resolvers/Images/Thumbnails.g.swift

@@ -0,0 +1,138 @@
+// Autogenerated from Pigeon (v26.0.0), do not edit directly.
+// See also: https://pub.dev/packages/pigeon
+
+import Foundation
+
+#if os(iOS)
+  import Flutter
+#elseif os(macOS)
+  import FlutterMacOS
+#else
+  #error("Unsupported platform.")
+#endif
+
+private func wrapResult(_ result: Any?) -> [Any?] {
+  return [result]
+}
+
+private func wrapError(_ error: Any) -> [Any?] {
+  if let pigeonError = error as? PigeonError {
+    return [
+      pigeonError.code,
+      pigeonError.message,
+      pigeonError.details,
+    ]
+  }
+  if let flutterError = error as? FlutterError {
+    return [
+      flutterError.code,
+      flutterError.message,
+      flutterError.details,
+    ]
+  }
+  return [
+    "\(error)",
+    "\(type(of: error))",
+    "Stacktrace: \(Thread.callStackSymbols)",
+  ]
+}
+
+private func isNullish(_ value: Any?) -> Bool {
+  return value is NSNull || value == nil
+}
+
+private func nilOrValue<T>(_ value: Any?) -> T? {
+  if value is NSNull { return nil }
+  return value as! T?
+}
+
+
+private class ThumbnailsPigeonCodecReader: FlutterStandardReader {
+}
+
+private class ThumbnailsPigeonCodecWriter: FlutterStandardWriter {
+}
+
+private class ThumbnailsPigeonCodecReaderWriter: FlutterStandardReaderWriter {
+  override func reader(with data: Data) -> FlutterStandardReader {
+    return ThumbnailsPigeonCodecReader(data: data)
+  }
+
+  override func writer(with data: NSMutableData) -> FlutterStandardWriter {
+    return ThumbnailsPigeonCodecWriter(data: data)
+  }
+}
+
+class ThumbnailsPigeonCodec: FlutterStandardMessageCodec, @unchecked Sendable {
+  static let shared = ThumbnailsPigeonCodec(readerWriter: ThumbnailsPigeonCodecReaderWriter())
+}
+
+
+/// Generated protocol from Pigeon that represents a handler of messages from Flutter.
+protocol ThumbnailApi {
+  func requestImage(assetId: String, requestId: Int64, width: Int64, height: Int64, isVideo: Bool, completion: @escaping (Result<[String: Int64], Error>) -> Void)
+  func cancelImageRequest(requestId: Int64) throws
+  func getThumbhash(thumbhash: String, completion: @escaping (Result<[String: Int64], Error>) -> Void)
+}
+
+/// Generated setup class from Pigeon to handle messages through the `binaryMessenger`.
+class ThumbnailApiSetup {
+  static var codec: FlutterStandardMessageCodec { ThumbnailsPigeonCodec.shared }
+  /// Sets up an instance of `ThumbnailApi` to handle messages through the `binaryMessenger`.
+  static func setUp(binaryMessenger: FlutterBinaryMessenger, api: ThumbnailApi?, messageChannelSuffix: String = "") {
+    let channelSuffix = messageChannelSuffix.count > 0 ? ".\(messageChannelSuffix)" : ""
+    let requestImageChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.immich_mobile.ThumbnailApi.requestImage\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
+    if let api = api {
+      requestImageChannel.setMessageHandler { message, reply in
+        let args = message as! [Any?]
+        let assetIdArg = args[0] as! String
+        let requestIdArg = args[1] as! Int64
+        let widthArg = args[2] as! Int64
+        let heightArg = args[3] as! Int64
+        let isVideoArg = args[4] as! Bool
+        api.requestImage(assetId: assetIdArg, requestId: requestIdArg, width: widthArg, height: heightArg, isVideo: isVideoArg) { result in
+          switch result {
+          case .success(let res):
+            reply(wrapResult(res))
+          case .failure(let error):
+            reply(wrapError(error))
+          }
+        }
+      }
+    } else {
+      requestImageChannel.setMessageHandler(nil)
+    }
+    let cancelImageRequestChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.immich_mobile.ThumbnailApi.cancelImageRequest\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
+    if let api = api {
+      cancelImageRequestChannel.setMessageHandler { message, reply in
+        let args = message as! [Any?]
+        let requestIdArg = args[0] as! Int64
+        do {
+          try api.cancelImageRequest(requestId: requestIdArg)
+          reply(wrapResult(nil))
+        } catch {
+          reply(wrapError(error))
+        }
+      }
+    } else {
+      cancelImageRequestChannel.setMessageHandler(nil)
+    }
+    let getThumbhashChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.immich_mobile.ThumbnailApi.getThumbhash\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
+    if let api = api {
+      getThumbhashChannel.setMessageHandler { message, reply in
+        let args = message as! [Any?]
+        let thumbhashArg = args[0] as! String
+        api.getThumbhash(thumbhash: thumbhashArg) { result in
+          switch result {
+          case .success(let res):
+            reply(wrapResult(res))
+          case .failure(let error):
+            reply(wrapError(error))
+          }
+        }
+      }
+    } else {
+      getThumbhashChannel.setMessageHandler(nil)
+    }
+  }
+}

mobile/ios/Runner/Resolvers/Request.swift

@@ -0,0 +1,20 @@
+class CancellationToken {
+  var isCancelled = false
+}
+
+class Request {
+  let cancellationToken: CancellationToken
+
+  init(cancellationToken: CancellationToken) {
+    self.cancellationToken = cancellationToken
+  }
+  
+  var isCancelled: Bool {
+    get {
+      return cancellationToken.isCancelled
+    }
+    set(newValue) {
+      cancellationToken.isCancelled = newValue
+    }
+  }
+}