using System;

namespace UnityEngine.Rendering
{
    /// <summary>
    /// Types of dynamic resolution that can be requested. Note that if Hardware is selected, but not available on the platform, the system will fallback to Software.
    /// </summary>
    public enum DynamicResolutionType : byte
    {
        /// <summary>
        /// Software dynamic resolution.
        /// </summary>
        Software,
        /// <summary>
        /// Hardware dynamic resolution.
        /// </summary>
        Hardware,
    }

    /// <summary>
    /// Types of filters that can be used to upscale rendered result to native resolution.
    /// </summary>
    public enum DynamicResUpscaleFilter : byte
    {
        /// <summary>
        /// Bilinear upscaling filter. Obsolete and not supported.
        /// </summary>
        [Obsolete("Bilinear upscale filter is considered obsolete and is not supported anymore, please use CatmullRom for a very cheap, but blurry filter.", false)] Bilinear,
        /// <summary>
        /// Bicubic Catmull-Rom upscaling filter.
        /// </summary>
        CatmullRom,
        /// <summary>
        /// Lanczos upscaling filter. Obsolete and not supported.
        /// </summary>
        [Obsolete("Lanczos upscale filter is considered obsolete and is not supported anymore, please use Contrast Adaptive Sharpening for very sharp filter or FidelityFX Super Resolution 1.0.", false)] Lanczos,
        /// <summary>
        /// Contrast Adaptive Sharpening upscaling filter.
        /// </summary>
        ContrastAdaptiveSharpen,
        /// <summary>
        /// FidelityFX Super Resolution 1.0
        /// </summary>
        [InspectorName("FidelityFX Super Resolution 1.0")]
        EdgeAdaptiveScalingUpres,
        /// <summary>
        /// Temporal Upscaling.
        /// </summary>
        [InspectorName("TAA Upscale")]
        TAAU
    }

    /// <summary>User-facing settings for dynamic resolution.</summary>
    [Serializable]
    public struct GlobalDynamicResolutionSettings
    {
        /// <summary>Default GlobalDynamicResolutionSettings</summary>
        /// <returns></returns>
        public static GlobalDynamicResolutionSettings NewDefault() => new GlobalDynamicResolutionSettings()
        {
            useMipBias = false,
            maxPercentage = 100.0f,
            minPercentage = 100.0f,
            // It fall-backs to software when not supported, so it makes sense to have it on by default.
            dynResType = DynamicResolutionType.Hardware,
            upsampleFilter = DynamicResUpscaleFilter.CatmullRom,
            forcedPercentage = 100.0f,
            lowResTransparencyMinimumThreshold = 0.0f,
            rayTracingHalfResThreshold = 50.0f,

            // Defaults for dlss
            enableDLSS = false,
            DLSSUseOptimalSettings = true,
            DLSSPerfQualitySetting = 0,
            DLSSSharpness = 0.5f,
            DLSSInjectionPoint = DynamicResolutionHandler.UpsamplerScheduleType.BeforePost,

            fsrOverrideSharpness = false,
            fsrSharpness = FSRUtils.kDefaultSharpnessLinear
        };

        /// <summary>Select whether the dynamic resolution is enabled or not.</summary>
        public bool enabled;
        /// <summary>Offsets the mip bias to recover mode detail. This only works if the camera is utilizing TAA.</summary>
        public bool useMipBias;

        /// <summary>Toggle NVIDIA Deep Learning Super Sampling (DLSS).</summary>
        public bool enableDLSS;

        /// <summary>Opaque quality setting of NVIDIA Deep Learning Super Sampling (DLSS). Use the system enum UnityEngine.NVIDIA.DLSSQuality to set the quality.</summary>
        public uint DLSSPerfQualitySetting;

        /// <summary>The injection point at which to apply DLSS upscaling.</summary>
        public DynamicResolutionHandler.UpsamplerScheduleType DLSSInjectionPoint;

        /// <summary>Toggle NVIDIA Deep Learning Super Sampling (DLSS) automatic recommendation system for scaling and sharpness.
        /// If this is on, the manually established scale callback for Dynamic Resolution Scaling is ignored. The sharpness setting of DLSS is also ignored.
        /// </summary>
        public bool DLSSUseOptimalSettings;

        /// <summary>Pixel sharpness of NVIDIA Deep Leraning Super Sampling (DLSS).</summary>
        [Range(0, 1)]
        public float DLSSSharpness;

        /// <summary>Toggle sharpness override for AMD FidelityFX Super Resolution (FSR).
        /// If this is on, a sharpness value specified by the user will be used instead of the default.
        /// </summary>
        public bool fsrOverrideSharpness;

        /// <summary>Pixel sharpness of AMD FidelityFX Super Resolution (FSR).</summary>
        [Range(0, 1)]
        public float fsrSharpness;

        /// <summary>The maximum resolution percentage that dynamic resolution can reach.</summary>
        public float maxPercentage;
        /// <summary>The minimum resolution percentage that dynamic resolution can reach.</summary>
        public float minPercentage;

        /// <summary>The type of dynamic resolution method.</summary>
        public DynamicResolutionType dynResType;
        /// <summary>The default of upscaling filter used. It can be overridden via the API DynamicResolutionHandler.SetUpscaleFilter </summary>
        public DynamicResUpscaleFilter upsampleFilter;

        /// <summary>Select whether dynamic resolution system will force a specific resolution percentage.</summary>
        public bool forceResolution;
        /// <summary>The resolution percentage forced in case forceResolution is set to true.</summary>
        public float forcedPercentage;

        /// <summary>The minimum percentage threshold allowed to clamp low resolution transparency. When the resolution percentage falls below this threshold, HDRP will clamp the low resolution to this percentage.</summary>
        public float lowResTransparencyMinimumThreshold;

        /// <summary>The minimum percentage threshold allowed to render ray tracing effects at half resolution. When the resolution percentage falls below this threshold, HDRP will render ray tracing effects at full resolution.</summary>
        public float rayTracingHalfResThreshold;
    }
}