#include "/Lib/Settings.glsl"
#include "/Lib/Utilities.glsl"
// MinecraftPT — Lighting Constants
// Per-frame lighting values computed inline (no SSBO dependency).
// These are cheap functions of the sun angle and camera position; computed
// per-pass instead of via a shared buffer for maximum loader compatibility.

#ifndef LIGHTING_CONSTANTS_GLSL
#define LIGHTING_CONSTANTS_GLSL

#include "/Lib/BasicFunctions/PrecomputedAtmosphere.glsl"

// Sun direction in world space (matches the shadow camera direction)
vec3 GetSunDirWorld(){
	#ifndef DIMENSION_NETHER
		#ifndef DIMENSION_END
			return normalize(shadowModelViewInverse2);
		#else
			return normalize(shadowModelViewInverse2) * fsign(0.5 - sunAngle);
		#endif
	#else
		return normalize(shadowModelViewInverse2) * fsign(0.5 - sunAngle);
	#endif
}

// Atmosphere camera position (scaled Earth radius + camera altitude)
vec3 GetAtmoCamera(){
	return vec3(0.0, max(cameraPosition.y, 63.0) * 0.001 + atmosphereModel_bottom_radius, 0.0);
}

// Sun irradiance (direct light color/intensity)
vec3 GetSunIrradiance(){
	vec3 sunDir = GetSunDirWorld();
	vec3 moon, sunSky, moonSky;
	return GetSunAndSkyIrradiance(GetAtmoCamera(), sunDir, -sunDir, moon, sunSky, moonSky);
}

vec3 GetMoonIrradiance(){
	vec3 sunDir = GetSunDirWorld();
	vec3 moon, sunSky, moonSky;
	GetSunAndSkyIrradiance(GetAtmoCamera(), sunDir, -sunDir, moon, sunSky, moonSky);
	return moon;
}

vec3 GetCelestialIrradiance(){
	return GetSunIrradiance() + GetMoonIrradiance();
}

vec3 GetAtmoIrradiance(){
	vec3 sunDir = GetSunDirWorld();
	vec3 moon, sunSky, moonSky;
	GetSunAndSkyIrradiance(GetAtmoCamera(), sunDir, -sunDir, moon, sunSky, moonSky);
	return sunSky + moonSky;
}

// Cloud-altitude irradiances
vec3 GetCloudSunIrradiance(){
	vec3 sunDir = GetSunDirWorld();
	vec3 atmoCamera = vec3(0.0, mix(CLOUD_CLEAR_ALTITUDE, CLOUD_RAIN_ALTITUDE, wetness) * 0.001 + atmosphereModel_bottom_radius, 0.0);
	vec3 moon, sunSky, moonSky;
	return GetSunAndSkyIrradiance(atmoCamera, sunDir, -sunDir, moon, sunSky, moonSky);
}

vec3 GetCloudAtmoIrradiance(){
	vec3 sunDir = GetSunDirWorld();
	vec3 atmoCamera = vec3(0.0, mix(CLOUD_CLEAR_ALTITUDE, CLOUD_RAIN_ALTITUDE, wetness) * 0.001 + atmosphereModel_bottom_radius, 0.0);
	vec3 moon, sunSky, moonSky;
	GetSunAndSkyIrradiance(atmoCamera, sunDir, -sunDir, moon, sunSky, moonSky);
	return sunSky + moonSky;
}

// Moon/sun phase for fog time factor
vec2 GetFogTimeFactor(){
	vec3 sunDir = GetSunDirWorld();
	float timeNoon = pow(1.0 - (clamp(sunDir.y, 0.2, 0.99) - 0.2) / 0.8, 6.0);
	float moonlightStrength = curve(saturate(sunDir.y * -5.0));
	return vec2(timeNoon, moonlightStrength);
}

// Dimension-aware irradiance override
vec3 GetDimensionAmbient(){
	#ifdef DIMENSION_NETHER
		return vec3(0.08, 0.02, 0.01) * NETHER_BRIGHTNESS;
	#elif defined DIMENSION_END
		return vec3(0.02, 0.02, 0.04);
	#else
		return GetAtmoIrradiance();
	#endif
}

#endif