// // CacheSerializer.swift // Kingfisher // // Created by Wei Wang on 2016/09/02. // // Copyright (c) 2019 Wei Wang // // 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 import CoreGraphics /// An `CacheSerializer` is used to convert some data to an image object after /// retrieving it from disk storage, and vice versa, to convert an image to data object /// for storing to the disk storage. public protocol CacheSerializer { /// Gets the serialized data from a provided image /// and optional original data for caching to disk. /// /// - Parameters: /// - image: The image needed to be serialized. /// - original: The original data which is just downloaded. /// If the image is retrieved from cache instead of /// downloaded, it will be `nil`. /// - Returns: The data object for storing to disk, or `nil` when no valid /// data could be serialized. func data(with image: KFCrossPlatformImage, original: Data?) -> Data? /// Gets an image from provided serialized data. /// /// - Parameters: /// - data: The data from which an image should be deserialized. /// - options: The parsed options for deserialization. /// - Returns: An image deserialized or `nil` when no valid image /// could be deserialized. func image(with data: Data, options: KingfisherParsedOptionsInfo) -> KFCrossPlatformImage? /// Gets an image deserialized from provided data. /// /// - Parameters: /// - data: The data from which an image should be deserialized. /// - options: Options for deserialization. /// - Returns: An image deserialized or `nil` when no valid image /// could be deserialized. /// - Note: /// This method is deprecated. Please implement the version with /// `KingfisherParsedOptionsInfo` as parameter instead. @available(*, deprecated, message: "Deprecated. Implement the method with same name but with `KingfisherParsedOptionsInfo` instead.") func image(with data: Data, options: KingfisherOptionsInfo?) -> KFCrossPlatformImage? } extension CacheSerializer { public func image(with data: Data, options: KingfisherOptionsInfo?) -> KFCrossPlatformImage? { return image(with: data, options: KingfisherParsedOptionsInfo(options)) } } /// Represents a basic and default `CacheSerializer` used in Kingfisher disk cache system. /// It could serialize and deserialize images in PNG, JPEG and GIF format. For /// image other than these formats, a normalized `pngRepresentation` will be used. public struct DefaultCacheSerializer: CacheSerializer { /// The default general cache serializer used across Kingfisher's cache. public static let `default` = DefaultCacheSerializer() /// The compression quality when converting image to a lossy format data. Default is 1.0. public var compressionQuality: CGFloat = 1.0 /// Whether the original data should be preferred when serializing the image. /// If `true`, the input original data will be checked first and used unless the data is `nil`. /// In that case, the serialization will fall back to creating data from image. public var preferCacheOriginalData: Bool = false /// Creates a cache serializer that serialize and deserialize images in PNG, JPEG and GIF format. /// /// - Note: /// Use `DefaultCacheSerializer.default` unless you need to specify your own properties. /// public init() { } /// - Parameters: /// - image: The image needed to be serialized. /// - original: The original data which is just downloaded. /// If the image is retrieved from cache instead of /// downloaded, it will be `nil`. /// - Returns: The data object for storing to disk, or `nil` when no valid /// data could be serialized. /// /// - Note: /// Only when `original` contains valid PNG, JPEG and GIF format data, the `image` will be /// converted to the corresponding data type. Otherwise, if the `original` is provided but it is not /// If `original` is `nil`, the input `image` will be encoded as PNG data. public func data(with image: KFCrossPlatformImage, original: Data?) -> Data? { if preferCacheOriginalData { return original ?? image.kf.data( format: original?.kf.imageFormat ?? .unknown, compressionQuality: compressionQuality ) } else { return image.kf.data( format: original?.kf.imageFormat ?? .unknown, compressionQuality: compressionQuality ) } } /// Gets an image deserialized from provided data. /// /// - Parameters: /// - data: The data from which an image should be deserialized. /// - options: Options for deserialization. /// - Returns: An image deserialized or `nil` when no valid image /// could be deserialized. public func image(with data: Data, options: KingfisherParsedOptionsInfo) -> KFCrossPlatformImage? { return KingfisherWrapper.image(data: data, options: options.imageCreatingOptions) } }