#version 330

// Uniforms
uniform mat4 matrixView;
uniform sampler2D texture0;

uniform vec3 materialAmbient;
uniform vec3 materialDiffuse;

uniform float time;
uniform int upper;
uniform int middle;
uniform float shadowStrength;
uniform bool brightnessTest;
uniform bool bloomView;

// Input Variables
in vec4 color;
in vec4 position;
in vec3 normal;
in vec2 texCoord0;

// Output Variable
out vec4 outColor;




// point light declaration
struct POINT
{
	int on;
	vec3 position;
	vec3 diffuse;
	vec3 specular;
};
uniform POINT lightPoint;




// point light function
vec4 PointLight(POINT light)
{

	// diffuse light
	vec4 color = vec4(0, 0, 0, 1);
	vec3 L = normalize((matrixView * vec4(light.position, 1)) - position).xyz;
	float NdotL = dot(L, normal);
	if (NdotL > 0)
	{
		color += vec4 (light.diffuse * materialDiffuse, 1) * NdotL;
	}
	else
	{
		// add slight extended lighting past cut-off point, totalling around 3/5ths of a sphere
		// immitating light bending in atmosphere.
		// increase positive NdotL multiplier to bring ratio closer to original cut-off
		// with this, increase -NdotL alpha multiplier to blend darker side to transparency
		color = vec4(materialDiffuse * light.diffuse, 1.0) * (NdotL * 1.0) - vec4(0.0, 0.0, 0.0, (-NdotL * 4.0));
		// sunset
		color += vec4(clamp(0.0 - (NdotL * 2.0), 0.0, 0.3), clamp(0.0 - (NdotL * 2.0), 0.0, 0.07), 0.0, 0.0);
	}

	// specular specular
	//vec3 V = normalize(-position.xyz);
	//vec3 R = reflect(-L, finalNormal);
	//float RdotV = dot(R, V);
	//if (NdotL > 0 && RdotV > 0)
	//{
	//	color += vec4(light.specular * materialSpecular * pow(RdotV, shininess), 1);
	//}

	return color;
}



void main(void)
{
	outColor = color;

	if (lightPoint.on == 1) outColor += PointLight(lightPoint);

	// give the inner clouds .y value some 'bounce'
	//float frequency = 4.0;
	//float amplitude = 0.01;

	// perhaps too costly, moved equivelent to main.cpp
	//if (upper == 1) outColor *= texture(texture0, vec2(texCoord0.x + time / 300000.0, texCoord0.y));
	//if (middle == 1) outColor *= texture(texture0, vec2(texCoord0.x + time / 150000.0, texCoord0.y + amplitude * sin(texCoord0.x * frequency + time / 3000)));

	if (upper == 1) outColor *= texture(texture0, texCoord0);
	if (middle == 1) outColor *= texture(texture0, texCoord0);

	// brightness test for bloom PPE
	if (brightnessTest)
	{
		float brightness = dot(outColor.rgb, vec3(0.2126, 0.7152, 0.0722));
		if (brightness > 1.0) outColor = outColor;
		if (bloomView)
		{
			// in order for the brightness test to pass through the alpha parts atmosphere, it needs to be treated in the same way
			// as within the pointlight struct. where the light is closest, put alpha at 1, where the alpha of the atmosphere is 0
			// (dark side of the planet) give it an alpha of 0 in the brightness test, to give chance for the earth lights to pass the brightness test
			// IF THE VIEW IS INNER EARTH (bloomview = true)
			// ELSE give an alpha of 0 to be able to see through the atmopshere alpha
			vec3 L = normalize((matrixView * vec4(lightPoint.position, 1)) - position).xyz;
			float NdotL = dot(L, normal);

			if (NdotL > 0) outColor = vec4(0.0, 0.0, 0.0, 1.0);
			else outColor = vec4(0.0, 0.0, 0.0, 0.0);
		}
		if (!bloomView) outColor = vec4(0.0, 0.0, 0.0, 0.0);
	//outColor = vec4(0.0, 0.0, 0.0, 1.0);
	}
}