element-ios/Riot/Managers/URLPreviews/Core Data/URLPreviewImageTransformer....

37 lines
1.1 KiB
Swift

//
// Copyright 2021-2024 New Vector Ltd.
//
// SPDX-License-Identifier: AGPL-3.0-only
// Please see LICENSE in the repository root for full details.
//
import CoreData
/// A `ValueTransformer` for ``URLPreviewCacheData``'s `image` field.
/// This class transforms between `UIImage` and it's `pngData()` representation.
class URLPreviewImageTransformer: ValueTransformer {
override class func transformedValueClass() -> AnyClass {
UIImage.self
}
override class func allowsReverseTransformation() -> Bool {
true
}
/// Transforms a `UIImage` into it's `pngData()` representation.
override func transformedValue(_ value: Any?) -> Any? {
guard let image = value as? UIImage else { return nil }
return image.pngData()
}
/// Transforms `Data` into a `UIImage`
override func reverseTransformedValue(_ value: Any?) -> Any? {
guard let data = value as? Data else { return nil }
return UIImage(data: data)
}
}
extension NSValueTransformerName {
static let urlPreviewImageTransformer = NSValueTransformerName("URLPreviewImageTransformer")
}