Move across basic WebP Swift wrapper from stackotter/swift-libwebp

Sources/WebP/WebP.swift

@@ -1,11 +1,69 @@
 // SPDX-License-Identifier: BSD-3-Clause
 // Copyright Contributors to the WebP Codec project
 
-@_exported import libwebp
-@_exported import sharpyuv
-@_exported import imageioutil
+import libwebp
+import Foundation
 
-public enum WebP
+public enum WebPError: Error
 {
-  public static let version = "1.4.0"
+    case unknownDecodingError
+    case unknownEncodingError
+}
+
+public struct WebP
+{
+    public static let version = "1.4.0"
+
+    public var width: Int
+    public var height: Int
+    public var rgba: [UInt8]
+
+    public init(width: Int, height: Int, rgba: [UInt8])
+    {
+        self.width = width
+        self.height = height
+        self.rgba = rgba
+    }
+
+    public static func decode(_ data: [UInt8]) throws -> WebP
+    {
+        var width: Int32 = 0
+        var height: Int32 = 0
+        guard let rgba = WebPDecodeRGBA(data, data.count, &width, &height) else
+        {
+            throw WebPError.unknownDecodingError
+        }
+
+        let webp = WebP(
+            width: Int(width),
+            height: Int(height),
+            rgba: [UInt8](Data(bytes: rgba, count: Int(width * height * 4)))
+        )
+        WebPFree(rgba)
+        return webp
+    }
+
+    /// - Parameter quality: A value from 0 to 100 which controls output quality. 100 produces
+    ///   the best quality output but also the largest output.
+    public func encode(quality: Float) throws -> [UInt8]
+    {
+        var data: UnsafeMutablePointer<UInt8>?
+        let size = WebPEncodeRGBA(
+            rgba,
+            Int32(width),
+            Int32(height),
+            Int32(width * 4),
+            quality,
+            &data
+        )
+
+        guard let data = data else
+        {
+            throw WebPError.unknownEncodingError
+        }
+
+        let dataCopy = [UInt8](Data(bytes: data, count: Int(size)))
+        WebPFree(data)
+        return dataCopy
+    }
 }