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// ---------------------------------------------------------------------
// %COPYRIGHT_BEGIN%
// Copyright (c) (2018-2022) Magic Leap, Inc. All Rights Reserved.
// Use of this file is governed by the Software License Agreement, located here: https://www.magicleap.com/software-license-agreement-ml2
// Terms and conditions applicable to third-party materials accompanying this distribution may also be found in the top-level NOTICE file appearing herein.
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using System.Runtime.InteropServices;

namespace UnityEngine.XR.MagicLeap
{
    public partial class MLNativeSurface
    {
        public enum PixelFormat
        {
            /*! Custom */
            Custom = -4,
            /*! Translucent */
            Translucent = -3,
            /*! Transparent */
            Transparent = -2,
            /*! Opaque */
            Opaque = -1,
            /*! None */
            None = 0,
            /*! 4x8-bit RGBA */
            Rgba8888 = 1,
            /*! 4x8-bit RGBX */
            Rgbx8888 = 2,
            /*! 3x8-bit RGB */
            Rgb888 = 3,
            /*! 16-bit RGB */
            Rgb565 = 4,
            /*! 4x8-bit BGRA */
            Bgra8888 = 5,
            /*! 64-bit RGBA */
            RgbaFp16 = 22,
            /*! 32-bit RGBA */
            Rgba1010102 = 43,
        }

        public delegate void OnFrameAvailableDelegate();

        public ulong Handle { get; private set; }

        public event OnFrameAvailableDelegate OnFrameAvailable = delegate { };

        private GCHandle gcHandle;
        private readonly bool isExternallyOwned;

        public MLNativeSurface(PixelFormat pixelFormat, ushort bufferCount, uint width, uint height)
        {
            gcHandle = GCHandle.Alloc(this, GCHandleType.Weak);
            isExternallyOwned = false;
            Handle = Native.MagicLeapNativeBindings.InvalidHandle;
            NativeBindings.MLNativeSurfaceConfig config = new NativeBindings.MLNativeSurfaceConfig(pixelFormat, bufferCount, width, height);
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceCreate(ref config, out ulong nativeSurfaceHandle);
            if (MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceCreate)))
            {
                Handle = nativeSurfaceHandle;

                NativeBindings.MLNativeSurfaceOnFrameAvailableCallback frameInfo = NativeBindings.MLNativeSurfaceOnFrameAvailableCallback.Create();
                resultCode = NativeBindings.MLNativeSurfaceSetOnFrameAvailableCallback(Handle, ref frameInfo, GCHandle.ToIntPtr(gcHandle));
                MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceSetOnFrameAvailableCallback));
            }
        }

        /// <summary>
        /// For externally owned native surface, like in the case of MLMediaRecorder
        /// </summary>
        /// <param name="surfaceHandle"></param>
        public MLNativeSurface(ulong surfaceHandle)
        {
            Handle = surfaceHandle;
            isExternallyOwned = true;
        }

        ~MLNativeSurface()
        {
            Destroy();
        }

        public MLResult Destroy()
        {
            MLResult.Code resultCode = MLResult.Code.NotImplemented;

            if (!isExternallyOwned)
            {
                if (gcHandle.IsAllocated)
                {
                    gcHandle.Free();;
                }
                if (Native.MagicLeapNativeBindings.MLHandleIsValid(Handle))
                {
                    resultCode = NativeBindings.MLNativeSurfaceRelease(Handle);
                    MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceRelease));
                    Handle = Native.MagicLeapNativeBindings.InvalidHandle;
                }
            }
            return MLResult.Create(resultCode);
        }

        public MLResult AcquireNextAvailableFrame(out ulong nativeBuffer)
        {
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceAcquireNextAvailableFrame(Handle, out nativeBuffer);
            MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceAcquireNextAvailableFrame));
            return MLResult.Create(resultCode);
        }

        public MLResult ReleaseFrame(ulong nativeBuffer)
        {
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceReleaseFrame(Handle, nativeBuffer);
            MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceReleaseFrame));
            return MLResult.Create(resultCode);
        }

        public MLResult GetFrameTransformMatrix(float[] frameTransformMatColMajor)
        {
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceGetFrameTransformationMatrix(Handle, frameTransformMatColMajor);
            MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceGetFrameTransformationMatrix));
            return MLResult.Create(resultCode);
        }

        public MLResult GetFrameTimestamp(out long timestampNs)
        {
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceGetFrameTimestamp(Handle, out timestampNs);
            MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceGetFrameTimestamp));
            return MLResult.Create(resultCode);
        }

        public MLResult GetFrameQueueBufferTimestamp(out long timestampNs)
        {
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceGetFrameQueueBufferTimestamp(Handle, out timestampNs);
            MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceGetFrameQueueBufferTimestamp));
            return MLResult.Create(resultCode);
        }

        public MLResult GetFrameNumber(out ulong number)
        {
            MLResult.Code resultCode = NativeBindings.MLNativeSurfaceGetFrameNumber(Handle, out number);
            MLResult.DidNativeCallSucceed(resultCode, nameof(NativeBindings.MLNativeSurfaceGetFrameNumber));
            return MLResult.Create(resultCode);
        }

        private void OnFrameAvailable_CallbackThread()
        {
            OnFrameAvailable.Invoke();
        }
    }
}