fix gif caching

Pocket Poster/Packages/GIFImage/Sources/GIFImage.swift

@@ -0,0 +1,137 @@
+import SwiftUI
+
+/// `GIFImage` is a `View` that loads a `Data` object from a source into `CoreImage.CGImageSource`, parse the image source
+/// into frames and stream them based in the "Delay" key packaged on which frame item. The view will use the `ImageLoader` from the environment
+/// to convert the fetch the `Data`
+public struct GIFImage: View {
+    public let source: GIFSource
+    public let placeholder: RawImage
+    public let errorImage: RawImage?
+    private let presentationController: PresentationController
+
+    @Environment(\.imageLoader) var imageLoader
+    @State @MainActor private var frame: RawImage?
+    @Binding public var loop: Bool
+    @Binding public var animate: Bool
+    @State private var presentationTask: Task<(), Never>?
+
+    /// `GIFImage` is a `View` that loads a `Data` object from a source into `CoreImage.CGImageSource`, parse the image source
+    /// into frames and stream them based in the "Delay" key packaged on which frame item.
+    ///
+    /// - Parameters:
+    ///   - source: Source of the image. If the source is remote, the response is cached using `URLCache`
+    ///   - animate: A flag to indicate that GIF should animate or not. If non-animated, the first frame will be displayed
+    ///   - loop: Flag to indicate if the GIF should be played only once or continue to loop
+    ///   - placeholder: Image to be used before the source is loaded
+    ///   - errorImage: If the stream fails, this image is used
+    ///   - frameRate: Option to control the frame rate of the animation or to use the GIF information about frame rate
+    ///   - loopAction: Closure called whenever the GIF finishes rendering one cycle of the action
+    public init(
+        source: GIFSource,
+        animate: Bool,
+        loop: Bool,
+        placeholder: RawImage = RawImage(),
+        errorImage: RawImage? = nil,
+        frameRate: FrameRate = .dynamic,
+        loopAction: @Sendable @escaping (GIFSource) async throws -> Void = { _ in }
+    ) {
+        self.init(
+            source: source,
+            animate: .constant(animate),
+            loop: .constant(loop),
+            placeholder: placeholder,
+            errorImage: errorImage,
+            frameRate: frameRate,
+            loopAction: loopAction
+        )
+    }
+    
+    /// `GIFImage` is a `View` that loads a `Data` object from a source into `CoreImage.CGImageSource`, parse the image source
+    /// into frames and stream them based in the "Delay" key packaged on which frame item.
+    ///
+    /// - Parameters:
+    ///   - source: Source of the image. If the source is remote, the response is cached using `URLCache`
+    ///   - loop: Flag to indicate if the GIF should be played only once or continue to loop
+    ///   - placeholder: Image to be used before the source is loaded
+    ///   - errorImage: If the stream fails, this image is used
+    ///   - frameRate: Option to control the frame rate of the animation or to use the GIF information about frame rate
+    ///   - loopAction: Closure called whenever the GIF finishes rendering one cycle of the action
+    public init(
+        source: GIFSource,
+        animate: Binding<Bool> = Binding.constant(true),
+        loop: Binding<Bool> = Binding.constant(true),
+        placeholder: RawImage = RawImage(),
+        errorImage: RawImage? = nil,
+        frameRate: FrameRate = .dynamic,
+        loopAction: @Sendable @escaping (GIFSource) async throws -> Void = { _ in }
+    ) {
+        self.source = source
+        self._animate = animate
+        self._loop = loop
+        self.placeholder = placeholder
+        self.errorImage = errorImage
+        
+        self.presentationController = PresentationController(
+            source: source,
+            frameRate: frameRate,
+            animate: animate,
+            loop: loop,
+            action: loopAction
+        )
+    }
+
+    public var body: some View {
+        Image.loadImage(with: frame ?? placeholder)
+            .resizable()
+            .scaledToFit()
+            .onChange(of: loop) { newValue in
+                handle(loop: newValue)
+            }
+            .onChange(of: animate) { newValue in
+                handle(animate: newValue)
+            }
+            .task(id: source, load)
+    }
+
+    private func handle(animate: Bool) {
+        if animate {
+            load()
+        } else {
+            presentationTask?.cancel()
+        }
+    }
+    
+    private func handle(loop: Bool) {
+        if loop { load() }
+    }
+    
+    @Sendable private func load() {
+        presentationTask?.cancel()
+        presentationTask = Task { await presentationController.start(
+            imageLoader: imageLoader,
+            fallbackImage: errorImage ?? placeholder,
+            frameUpdate: setFrame(_:)
+        )}
+    }
+    
+    @MainActor
+    @Sendable private func setFrame(_ frame: RawImage) async {
+        self.frame = frame
+    }
+}
+
+#if DEBUG
+let placeholder = RawImage.create(symbol: "photo.circle.fill")!
+let error = RawImage.create(symbol: "xmark.octagon")
+let gifURL = "https://raw.githubusercontent.com/igorcferreira/GIFImage/main/Tests/test.gif"
+#Preview("Raw URL") {
+    GIFImage(url: gifURL, placeholder: placeholder, errorImage: error)
+}
+#Preview("Limited 5 FPS") {
+    GIFImage(url: gifURL, placeholder: placeholder, errorImage: error, frameRate: .limited(fps: 5))
+}
+#Preview("Limited to 30 FPS") {
+    GIFImage(url: gifURL, placeholder: placeholder, errorImage: error, frameRate: .static(fps: 30))
+}
+#endif
+