#version 330 core

in vec2 vUV;
out vec4 FragColor;

uniform sampler2D albedo;
uniform sampler2D normalMap;
uniform int normalEnabled;
uniform float normalStrength;
uniform vec3 tint;
uniform int radialEnabled; 
uniform float radialInner; 
uniform float radialOuter; 

void main()
{
    vec4 tex = texture(albedo, vUV);
    vec3 color = tex.rgb * tint;
    float alpha = tex.a;
    vec3 finalNormal = vec3(0.0, 0.0, 1.0);
    if (normalEnabled == 1)
    {
        vec3 n = texture(normalMap, vUV).rgb;
        n = n * 2.0 - 1.0;
        finalNormal = normalize(vec3(n.x * normalStrength, n.y * normalStrength, 1.0));
    }
    if (radialEnabled == 1)
    {
        
        float dist = distance(vUV, vec2(0.5, 0.5));
        
        float mask = 1.0 - smoothstep(radialInner, radialOuter, dist);
        alpha *= mask;
    }
    
    if (normalEnabled == 1)
    {
        vec3 lightDir = normalize(vec3(0.3, 1.0, 0.5));
        float l = max(dot(normalize(finalNormal), lightDir), 0.0);
        
        color *= (0.4 + 0.6 * l);
    }

    FragColor = vec4(color, alpha);
}