dmytro-anokhin

enum SubsamplingLevel: Int {

    case level0 = 1

    case level1 = 2

    case level2 = 4

    case level3 = 8

dmytro-anokhin

private static let imageSourceOptions: [CFString: Any] = [
    kCGImageSourceShouldCache: true
]

private static let imageSourceAsyncOptions: [CFString: Any] = [
    kCGImageSourceShouldCacheImmediately: true,
    kCGImageSourceCreateThumbnailFromImageAlways: true
]

dmytro-anokhin

func frameSize(at index: Int, subsamplingLevel: SubsamplingLevel = .default) -> CGSize? {
    guard let properties = CGImageSourceCopyPropertiesAtIndex(imageSource, index, imageSourceOptions(with: subsamplingLevel)) as? [CFString: Any] else {
        return nil
    }

    guard let width = properties[kCGImagePropertyPixelWidth] as? Int, let height = properties[kCGImagePropertyPixelHeight] as? Int else {
        return nil
    }

    return CGSize(width: width, height: height)

dmytro-anokhin

func frameDuration(at index: Int) -> TimeInterval? {
    guard let frameProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, index, imageSourceOptions()) as? [CFString: Any] else {
        return nil
    }

    var animationProperties = ImageDecoder.animationProperties(from: frameProperties)

    if animationProperties == nil {
        if let properties = CGImageSourceCopyProperties(imageSource, imageSourceOptions()) as? [CFString: Any] {
            animationProperties = ImageDecoder.animationHEICSProperties(from: properties, at: index)

dmytro-anokhin

var frameCount: Int {
    CGImageSourceGetCount(imageSource)
}

dmytro-anokhin

private(set) var isAllDataReceived: Bool = false

func setData(_ data: Data, allDataReceived: Bool) {
    assert(!isAllDataReceived)

    isAllDataReceived = allDataReceived
    CGImageSourceUpdateData(imageSource, data as CFData, allDataReceived)
}

dmytro-anokhin

class ImageDecoder {
    
    init() {
        imageSource = CGImageSourceCreateIncremental(nil)
    }
    
    private let imageSource: CGImageSource
}

dmytro-anokhin

let modelDescription = CoreDataModelDescription(
    entities: [
        .entity(
            name: "Author",
            managedObjectClass: Author.self,
            attributes: [
                .attribute(name: "name", type: .stringAttributeType)
            ],
            relationships: [
                .relationship(name: "publications", destination: "Publication", toMany: true, deleteRule: .cascadeDeleteRule, inverse: "author")

dmytro-anokhin

let model = NSManagedObjectModel()
model.entities = [ authorEntity, publicationEntity, articleEntity ]

dmytro-anokhin

final class Author: NSManagedObject {
    @NSManaged var name: String?
    @NSManaged public var publications: NSSet?
}

class Publication: NSManagedObject {
    @NSManaged var publicationDate: Date?
    @NSManaged var numberOfViews: Int64
    @NSManaged var author: Author?
}