#version 330 core
out vec4 FragColor;


uniform vec3 lightColor;
uniform vec3 objectColor;
uniform vec3 viewPos;

in vec3 FragPos;
in vec3 Normal;
in vec3 LightPos;

const float ambientStrength = 0.2;
const float shininess = 32.0;
const float screenGamma = 2.2; // Assume the monitor is calibrated to the sRGB color space

void main()
{
    // FragColor = vec4(1.0f, 0.0f, 0.0f, 1.0f);

    vec3 lightDir = LightPos - FragPos;
    float distance = length(lightDir);
    vec3 norm = normalize(Normal);
    vec3 ambient = ambientStrength * lightColor;

    distance = distance * distance;
    lightDir = normalize(lightDir);

    float lambertian = max(dot(norm, lightDir), 0.0);
    vec3 diffuse = lambertian * lightColor;
    float specular = 0.0;

    if (lambertian > 0.0)
    {
        vec3 viewDir = normalize(-FragPos);

        vec3 halfDir = normalize(lightDir + viewDir);
        float specAngle = max(dot(halfDir, norm), 0.0);
        specular = pow(specAngle, shininess);
    }

    vec3 colorLinear = (ambient + diffuse + specular) * objectColor;

    // vec3 colorGammaCorrected = pow(colorLinear, vec3(1.0 / screenGamma));

    FragColor = vec4(colorLinear, 1.0);

    // vec3 norm = normalize(Normal);
}