#version 330 core

uniform vec3 light_color;
uniform vec3 light_pos;

uniform float ambient_light_strength;
uniform float specular_light_strength;

uniform uint specular_shininess;

vec3 calc_diffuse_light(in vec3 light_dir, in vec3 norm)
{
	float diff = max(dot(norm, light_dir), 0.0);

	return diff * light_color;
}

vec3 calc_specular_light(
	in vec3 light_dir,
	in vec3 norm,
	in vec3 view_pos,
	in vec3 frag_pos
)
{
	vec3 view_direction = normalize(view_pos - frag_pos);

	vec3 reflect_direction = reflect(-light_dir, norm);
	
	float spec =
		pow(max(dot(view_direction, reflect_direction), 0.0), specular_shininess);

	return specular_light_strength * spec * light_color;
}