#ifndef UTS_SINGLE_LIGHT_LOOP
#define UTS_SINGLE_LIGHT_LOOP

#include "Packages/com.misaki.hdrp-toon/Runtime/Models/SurfaceFeature.cs.hlsl"
#include "Packages/com.misaki.hdrp-toon/Runtime/Shaders/Includes/Common/UtsSurfaceFeatureEvaluation.hlsl"
#include "Packages/com.misaki.hdrp-toon/Runtime/Shaders/Includes/Lighting/UtsLightEvaluation.hlsl"

struct UtsSingleMainLight
{
    GPULightType lightType;
    uint lightIndex;
};

int GetMainLightIndex(BuiltinData builtinData)
{
    int mainLightIndex = -1;

    if (featureFlags & LIGHTFEATUREFLAGS_DIRECTIONAL)
    {
        DirectionalLightData light = _DirectionalLightDatas[_DirectionalShadowIndex];

        if ((light.lightDimmer > 0) && (light.shadowDimmer > 0) && IsMatchingLightLayer(light.lightLayers, builtinData.renderingLayers))
        {
            SHADOW_TYPE shadowValue = GetDirectionalShadowAttenuation(context.shadowContext,
                                        posInput.positionSS, _ObjectCenterPositionWS + L * _ShadowDistanceBias, UtsGetShadowNormal(bsdfData),
                                        light.shadowIndex, L);

            if (length(shadowValue) > 0.0)
            {
                mainLightIndex = _DirectionalShadowIndex;
            }
        }
    }

     return mainLightIndex;
}

// TODO: The process of finding main light index should be move to vertex stage
void UtsSingleLightLoop(FragInputs fragInputs, PositionInputs posInput, UtsBSDFData bsdfData, BuiltinData builtinData,
    float3 V, uint featureFlags, out LightLoopOutput lightLoopOutput)
{
    PreLightData preLightData = GetPreLightData_UTS(V, posInput, bsdfData);
    
    AggregateLighting aggregateLighting;
    ZERO_INITIALIZE(AggregateLighting, aggregateLighting);

#if _USER_LIGHT_SOURCE_LOOP_ON
    
#else
    int mainLightIndex = GetMainLightIndex(builtinData);
    
    if (mainLightIndex != -1 && featureFlags & LIGHTFEATUREFLAGS_PUNCTUAL)
    {
        
    }
#endif
}

#endif