#version 330

in vec4 pos_model;
in vec3 vec_normal;

out vec4 fragColor;

const int max = 1; // should change in cpu too

uniform vec4 couleur;
uniform vec4 lum_pos[max];
uniform mat4 view;
uniform vec4 lum_color[max];

void main() {
  const vec3 vue = vec3(0, 0, -1);
  const vec4 soleil_color = vec4(0.81f, 0.78f, 0.66f, 1.0f);

  fragColor = vec4(1);
  for(int i = 0; i < max; i++) {
    vec3 torche = normalize(pos_model.xyz - lum_pos[i].xyz);
    float intensite_lumineuse = clamp(dot(vec_normal, -torche), 0., 1.);
    vec3 reflet = (transpose(inverse(view)) * vec4(reflect(torche, vec_normal), 0)).xyz;
    float intensite_specularite = pow(clamp(dot(reflet, -vue), 0., 1.), 10);

    fragColor *= intensite_specularite * lum_color[i] + 0.1 * soleil_color + 0.9 * intensite_lumineuse * couleur;
  }
}