//========== Copyright (c) Valve Corporation, All rights reserved. ==========//
// paired with lightmappedgeneric_vs##

// STATIC: "DETAILTEXTURE"					"0..1"
// STATIC: "BUMPMAP"						"0..1"
// STATIC: "VERTEXCOLOR"					"0..1"
// STATIC: "SELFILLUM"						"0..1"
// STATIC: "DETAIL_ALPHA_MASK_BASE_TEXTURE"	"0..1"
// STATIC: "FLASHLIGHT"						"0..1"
// STATIC: "SEAMLESS"						"0..1"
// STATIC: "FLASHLIGHTDEPTHFILTERMODE"		"0..3"	[ps20b] [PC]
// STATIC: "FLASHLIGHTDEPTHFILTERMODE"		"0..2"	[ps30]  [PC]
// STATIC: "FLASHLIGHTDEPTHFILTERMODE"		"0..0"	[ps20b] [CONSOLE]
// STATIC: "SHADER_SRGB_READ"				"0..1"	[XBOX]
// STATIC: "SHADER_SRGB_READ"				"0..0"	[PC]
// STATIC: "SHADER_SRGB_READ"				"0..0"	[SONYPS3]

// diffuse bump map is always true when bumpmapping is enabled, so just set it to 1
#define DIFFUSEBUMPMAP 1

// DYNAMIC: "WRITEWATERFOGTODESTALPHA"		"0..1"
#include "common_fog_ps_fxc.h"
// DYNAMIC: "WRITE_DEPTH_TO_DESTALPHA"		"0..1" [ps20b] [ps30] [PC]
// DYNAMIC: "WRITE_DEPTH_TO_DESTALPHA"		"0..0" [ps20b] [CONSOLE]
// DYNAMIC: "FLASHLIGHTSHADOWS"				"0..1" [ps20b] [ps30]
// DYNAMIC: "UBERLIGHT"						"0..1" [ps30] [PC]

//	SKIP: $DETAILTEXTURE && ( $BUMPMAP && !$DETAIL_ALPHA_MASK_BASE_TEXTURE )
//	SKIP: $VERTEXCOLOR && $BUMPMAP
//  SKIP: $FLASHLIGHT && $SELFILLUM
//  SKIP: $FLASHLIGHT && $DETAIL_ALPHA_MASK_BASE_TEXTURE
//  SKIP: $FLASHLIGHT && $BUMPMAP

// We don't care about flashlight depth unless the flashlight is on
// SKIP: ( $FLASHLIGHT == 0 ) && ( $FLASHLIGHTSHADOWS == 1 )	[ps20b] [ps30]

// We don't care about uberlight unless the flashlight is on
// SKIP: ( $FLASHLIGHT == 0 ) && ( $UBERLIGHT == 1 )	[ps30]


#if defined( SHADER_MODEL_PS_2_0 )
#	define WRITE_DEPTH_TO_DESTALPHA 0
#endif


#define HDRTYPE HDR_TYPE_NONE
#include "shader_constant_register_map.h"
#include "common_flashlight_fxc.h"
#include "common_ps_fxc.h"

#define PIXELSHADER
#include "common_lightmappedgeneric_fxc.h"

const float4 g_SelfIllumTint						: register( c7 );
static const float g_OverbrightFactor = 2.0f;

const float3 g_EyePos							: register( c10 );
const float4 g_FogParams							: register( c11 );

const float3 g_FlashlightPos						: register( c15 );
// flashlightfixme: Move this math into the vertex shader.
const float4x4 g_FlashlightWorldToTexture		: register( c16 );

const float4 g_FlashlightAttenuationFactors		: register( c20 );

#if UBERLIGHT && defined( SHADER_MODEL_PS_3_0 )
const float3 g_vSmoothEdge0							: register( PSREG_UBERLIGHT_SMOOTH_EDGE_0 );		// ps_3_0 and up (over 32 registers)
const float3 g_vSmoothEdge1							: register( PSREG_UBERLIGHT_SMOOTH_EDGE_1 );
const float3 g_vSmoothOneOverWidth					: register( PSREG_UBERLIGHT_SMOOTH_EDGE_OOW );
const float4 g_vShearRound							: register( PSREG_UBERLIGHT_SHEAR_ROUND );
const float4 g_aAbB									: register( PSREG_UBERLIGHT_AABB );
const float4x4 g_FlashlightWorldToLight				: register( PSREG_UBERLIGHT_WORLD_TO_LIGHT );
#endif

sampler BaseTextureSampler			: register( s0 );
sampler LightmapSampler				: register( s1 );
sampler FlashlightSampler			: register( s2 );
sampler DetailSampler				: register( s3 );
sampler BumpmapSampler				: register( s4 );
sampler NormalizeSampler			: register( s6 );
sampler ShadowDepthSampler			: register( s7 );

#if defined(_PS3)
// Needed for optimal shadow filter code generation on PS3.
#pragma texformat ShadowDepthSampler DEPTH_COMPONENT24
#endif

#if (BUMPMAP == 1) && defined( _PS3 )
// Causes the Cg compiler to automatically produce _bx2 modifier on the texture load instead of producing a MAD to range expand the vector, saving one instruction.
#pragma texsign BumpmapSampler
#pragma texformat BumpmapSampler RGBA8
#endif

//PS_INPUT defined in common_lightmappedgeneric_fxc.h"

float4_color_return_type main( PS_INPUT i ) : COLOR
{
	bool bDetailTexture = DETAILTEXTURE ? true : false;
	bool bBumpmap = BUMPMAP ? true : false;
	bool bDiffuseBumpmap = DIFFUSEBUMPMAP ? true : false;
	bool bVertexColor = VERTEXCOLOR ? true : false;
	bool bSelfIllum = SELFILLUM ? true : false;
	bool bDetailAlphaMaskBaseTexture = DETAIL_ALPHA_MASK_BASE_TEXTURE ? true : false;
	bool bFlashlight = FLASHLIGHT ? true : false;
	float2 vBaseTexCoord;
	#if ( SEAMLESS )
	{
		vBaseTexCoord = i.SeamlessTexCoord.xy;
	}
	#else
	{
		vBaseTexCoord = i.BASETEXCOORD;
	}
	#endif

	float3 worldPos = i.worldPos_projPosZ.xyz;

	float3 lightmapColor1 = float3( 1.0f, 1.0f, 1.0f );
	float3 lightmapColor2 = float3( 1.0f, 1.0f, 1.0f );
	float3 lightmapColor3 = float3( 1.0f, 1.0f, 1.0f );
	if( bBumpmap && bDiffuseBumpmap )
	{
		float2 bumpCoord1;
		float2 bumpCoord2;
		float2 bumpCoord3;
		ComputeBumpedLightmapCoordinates( i.lightmapTexCoord1And2, i.lightmapTexCoord3_bumpTexCoord.xy,
			bumpCoord1, bumpCoord2, bumpCoord3 );
		
		float4 lightmapSample1 = tex2D( LightmapSampler, bumpCoord1 );
		lightmapColor1 = lightmapSample1.rgb;
		lightmapColor2 = tex2D( LightmapSampler, bumpCoord2 ).rgb;
		lightmapColor3 = tex2D( LightmapSampler, bumpCoord3 ).rgb;
	}
	else
	{
		if( !bFlashlight )
		{
			float2 bumpCoord1 = ComputeLightmapCoordinates( i.lightmapTexCoord1And2, i.lightmapTexCoord3_bumpTexCoord.xy );
			float4 lightmapSample1 = tex2D( LightmapSampler, bumpCoord1 );
			lightmapColor1 = lightmapSample1.rgb;
		}
	}

	float4 detailColor = float4( 1.0f, 1.0f, 1.0f, 1.0f );
	if( bDetailTexture )
	{
		detailColor = tex2D( DetailSampler, i.DETAILCOORD );
	}

	float4 baseColor = float4( 1.0f, 1.0f, 1.0f, 1.0f );
	baseColor = tex2Dsrgb( BaseTextureSampler, vBaseTexCoord );
	if ( bDetailAlphaMaskBaseTexture )
	{
		// This is what WorldTwoTextureBlend_DX6 does.
		baseColor.rgb = saturate( saturate( baseColor.rgb * 2 ) * detailColor.a + (1 - detailColor.a) );
		baseColor.rgb *= detailColor.rgb;
	}
	else
	{
		baseColor.rgb = lerp( baseColor.rgb, detailColor.rgb, detailColor.a );
	}
	
	float3 normal = float3( 0.0f, 0.0f, 1.0f );
	if( bBumpmap )
	{
		float3 normalTexel;
		normalTexel = tex2D( BumpmapSampler, i.BUMPCOORD ).xyz;
		normal = 2.0f * normalTexel - 1.0f;
	}

	float3 albedo = float3( 1.0f, 1.0f, 1.0f );
	float alpha = 1.0f;
	albedo *= baseColor.rgb;
	if( !bSelfIllum )
	{
		alpha *= baseColor.a;
	}

	// The vertex color contains the modulation color + vertex color combined
	albedo *= i.vertexColor.rgb;
	alpha  *= i.vertexColor.a; // not sure about this one

	float3 diffuseLighting;
	if( bFlashlight )
	{
		float3 worldSpaceNormal;
		if ( bBumpmap )
		{
			worldSpaceNormal = mul( normal, float3x3( i.tangentSpaceTranspose0_vertexBlendX.xyz, i.tangentSpaceTranspose1_bumpTexCoord2u.xyz, i.tangentSpaceTranspose2_bumpTexCoord2v.xyz ) );
		}
		else
		{
			worldSpaceNormal = i.tangentSpaceTranspose2_bumpTexCoord2v.xyz;
		}

		int nShadowSampleLevel = 0;
		bool bDoShadows = false;
// On ps_2_b, we can do shadow mapping
#if ( FLASHLIGHTSHADOWS && (defined(SHADER_MODEL_PS_2_B) || defined(SHADER_MODEL_PS_3_0) ) )
		nShadowSampleLevel = FLASHLIGHTDEPTHFILTERMODE;
		bDoShadows = true;
#endif
		
		float4 flashlightSpacePosition = TransformFlashlightWorldToTexture( worldPos, g_FlashlightWorldToTexture );

		diffuseLighting = DoFlashlight( g_FlashlightPos, worldPos, flashlightSpacePosition,
			worldSpaceNormal, g_FlashlightAttenuationFactors.xyz, 
			g_FlashlightAttenuationFactors.w, FlashlightSampler, ShadowDepthSampler, NormalizeSampler,
			nShadowSampleLevel, bDoShadows, float2(0, 0), false );

#if UBERLIGHT && defined( SHADER_MODEL_PS_3_0 )
	float4 uberLightPosition = mul( float4( worldPos, 1.0f ), g_FlashlightWorldToLight ).yzxw;
	diffuseLighting *= uberlight( uberLightPosition, g_vSmoothEdge0, g_vSmoothEdge1,
			    g_vSmoothOneOverWidth, g_vShearRound.xy, g_aAbB, g_vShearRound.zw );
#endif

	}
	else
	{
		if( bBumpmap && bDiffuseBumpmap )
		{
			float dot1 = saturate( dot( normal, bumpBasis[0] ) );
			float dot2 = saturate( dot( normal, bumpBasis[1] ) );
			float dot3 = saturate( dot( normal, bumpBasis[2] ) );

			float sum = dot1 + dot2 + dot3;
			diffuseLighting = dot1 * lightmapColor1 +
							  dot2 * lightmapColor2 +
							  dot3 * lightmapColor3;
			diffuseLighting *= 1.0f / sum;
		}
		else
		{
			diffuseLighting = lightmapColor1;
		}

		// Only scale here since the flashlight will already be scaled properly
		diffuseLighting *= g_OverbrightFactor;
	}

	float3 diffuseComponent = albedo * diffuseLighting;

	if( bSelfIllum )
	{
		float3 selfIllumComponent = g_SelfIllumTint.rgb * albedo;
		diffuseComponent = lerp( diffuseComponent, selfIllumComponent, baseColor.a );
	}

	float3 specularLighting = float3( 0.0f, 0.0f, 0.0f );
	float3 result = diffuseComponent + specularLighting;

	float fogFactor = CalcPixelFogFactor( PIXELFOGTYPE, g_FogParams, g_EyePos.xyz, worldPos, i.worldPos_projPosZ.w );

#if WRITEWATERFOGTODESTALPHA && (PIXELFOGTYPE == PIXEL_FOG_TYPE_HEIGHT)
	alpha = fogFactor;
#endif

	return FinalOutput( float4( result, alpha ), fogFactor, PIXELFOGTYPE, TONEMAP_SCALE_LINEAR, (WRITE_DEPTH_TO_DESTALPHA != 0), i.worldPos_projPosZ.w );
}