#version 330

uniform mat4 view;

out vec4 color;

in vec4 vertexColor;

in mat3 TBN;

in vec3 fPos;
in vec2 TCordinate;

uniform sampler2D diffuse;
uniform sampler2D roughness;
uniform sampler2D normal;

const vec3 lightColor = vec3(1.0f, 1.0f, 1.0f);
const vec3 lightDir = vec3(-1.0f, -1.0f, 1.0f);
const float ambient = 0.24f;
const float specularValue = 1.0f;

void main() {
	vec4 diffuseBase = texture(diffuse, TCordinate);

	vec3 normal = texture(normal, TCordinate).rgb;
	normal = normal * 2.0f - 1.0f;
	normal = normalize(mat3(view) * TBN * normal);
	
	vec3 lightNormal = normalize(vec3(view * vec4(lightDir, 0.0f)));
	
	float diffValue = max(dot(normal, lightNormal), 0.0f);
	float diffuse = diffValue;

	vec3 viewDir = normalize(-fPos);

	vec3 reflectDir = reflect(-lightNormal, normal);

	float spec = pow(max(dot(viewDir, reflectDir), 0.0f), 16);
	float specular = specularValue * spec;

	float roughness = texture(roughness, TCordinate).g;

	color = vertexColor * diffuseBase * vec4((ambient + diffuse) * lightColor, 1.0f) + vec4(roughness * specular * lightColor, 1.0f);
}