#ifndef UNIVERSAL_PARTICLES_SHADOW_CASTER_PASS_INCLUDED
#define UNIVERSAL_PARTICLES_SHADOW_CASTER_PASS_INCLUDED

#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Shadows.hlsl"

float3 _LightDirection;
float3 _LightPosition;

VaryingsShadowCasterParticle ShadowCasterParticlesVertex(AttributesShadowCasterParticle input)
{
    VaryingsShadowCasterParticle output = (VaryingsShadowCasterParticle)0;
    UNITY_SETUP_INSTANCE_ID(input);
    UNITY_TRANSFER_INSTANCE_ID(input, output);
    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(output);

    float3 positionWS = GetParticleVertexPositionInputs(input.positionOS.xyz).positionWS;
    float3 normalWS = GetParticleVertexNormalInputs(input.normalOS).normalWS;

#if _CASTING_PUNCTUAL_LIGHT_SHADOW
    float3 lightDirectionWS = normalize(_LightPosition - positionWS);
#else
    float3 lightDirectionWS = _LightDirection;
#endif

    float4 positionCS = TransformWorldToHClip(ApplyShadowBias(positionWS, normalWS, lightDirectionWS));
    output.positionCS = ApplyShadowClamping(positionCS);

#if defined(_ALPHATEST_ON)
    output.color = GetParticleColor(input.color);

    #if defined(_FLIPBOOKBLENDING_ON)
        #if defined(UNITY_PARTICLE_INSTANCING_ENABLED)
            GetParticleTexcoords(output.texcoord, output.texcoord2AndBlend, input.texcoords.xyxy, 0.0);
        #else
            GetParticleTexcoords(output.texcoord, output.texcoord2AndBlend, input.texcoords, input.texcoordBlend);
        #endif
    #else
        GetParticleTexcoords(output.texcoord, input.texcoords.xy);
    #endif
#endif

    return output;
}

half4 ShadowCasterParticlesFragment(VaryingsShadowCasterParticle input) : SV_TARGET
{
    UNITY_SETUP_INSTANCE_ID(input);
    UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(input);

#if defined(_ALPHATEST_ON)
    float2 uv = input.texcoord;
    half4 vertexColor = input.color;
    half4 baseColor = _BaseColor;

    #if defined(_FLIPBOOKBLENDING_ON)
        float3 blendUv = input.texcoord2AndBlend;
    #else
        float3 blendUv = float3(0, 0, 0);
    #endif

    half4 albedo = BlendTexture(UnityBuildTexture2DStructNoScaleNoTexelSize(_BaseMap), uv, blendUv) * baseColor;
    half4 colorAddSubDiff = half4(0, 0, 0, 0);
    #if defined(_COLORADDSUBDIFF_ON)
        colorAddSubDiff = _BaseColorAddSubDiff;
    #endif
    albedo = MixParticleColor(albedo, vertexColor, colorAddSubDiff);
    AlphaDiscard(albedo.a, _Cutoff);
#endif

    return 0;
}

#endif // UNIVERSAL_PARTICLES_SHADOW_CASTER_PASS_INCLUDED