#version 440

in vec3 f_color;
out vec4 FragColors;

uniform vec3 Kd;
uniform vec3 Ka;
uniform vec3 Ks;
uniform float Shininess;

struct LightInfo {
  vec4 Position; 
  vec3 Intensity; 
};

uniform LightInfo Light[64];
uniform int LightCount;

in vec3 fNormal;
in vec3 pos;

void main()
{ 

	vec3 finalColor;
	vec3 ambient;

	ambient = Ka * Light[0].Intensity;
	for (int i=0; i< LightCount; i++) 
	{   
    vec3 L = normalize(Light[i].Position.xyz - pos);
	vec3 N = fNormal;
	vec3 V = normalize(-pos);	
	//vec3 R = normalize(reflect(-L, N));
	vec3 H = normalize(V + L);

	//Discretizing the diffuse component between (here 3) levels

	const int levels = 3;
	const float scaleFactor = 1.0 / levels;
	float cosine = dot(L, N); // Between 0 and 1
	float value = floor( cosine * levels) * scaleFactor;

	vec3 diffuse = Kd * Light[i].Intensity * max(dot(L, N), 0.0) * value;
	
	// Not needed for cartoon shader	
	//vec3 specular = Ks * Light[i].Intensity * pow(max(dot(H, N), 0.0), Shininess);

	//dirty trick to stay with the same shader params
	finalColor = finalColor + diffuse;

    }
	
   FragColors = vec4(finalColor + ambient, 1);   
}