#version 450

const int MAX_TEXTURES = 256;

layout(location = 0) in vec4 inPos;
layout(location = 1) in vec3 inNormal;
layout(location = 2) in vec3 inTangent;
layout(location = 3) in vec3 inBitangent;
layout(location = 4) in vec2 inTextCoords;

layout(location = 1) out vec4 outAlbedo ;
layout(location = 0) out vec4 outPos;
layout(location = 2) out vec4 outNormal;
layout(location = 3) out vec4 outPBR;
layout(location = 4) out vec4 outEmissive;
layout(location = 5) out vec4 outTranslucency;
layout(location = 6) out vec4 outOpacity;

struct Material {
    vec4 diffuseColor; //16
    uint hasTexture; //20
    uint textureIdx; //24
    uint hasNormalMap; //28
    uint normalMapIdx; //32
    uint hasRoughMap;  //36
    uint roughMapIdx;  //40
    float roughnessFactor; //44
    float metallicFactor;  //48
    vec4 emissiveColour; //64
    uint hasEmissiveMap;  //68
    uint emissiveMapIdx;  //72
    uint hasTranslucencyMap;  //76
    uint translucencyMapIdx;  //80
    float translucencyFactor;  //84
    uint hasOpacityMap;  //88
    uint OpacityMapIdx;  //92
    float OpacityFactor;  //96
};
layout(set = 2, binding = 0) readonly buffer MaterialUniform {
    Material materials[];
} matUniform;
layout(set = 3, binding = 0) uniform sampler2D textSampler[MAX_TEXTURES];

vec3 calcNormal(Material material, vec3 normal, vec2 textCoords, mat3 TBN)
{
    vec3 newNormal = normal;
    if (material.hasNormalMap > 0)
    {
        newNormal = texture(textSampler[material.normalMapIdx], textCoords).rgb;
        newNormal = normalize(newNormal * 2.0 - 1.0);
        newNormal = normalize(TBN * newNormal);
    }
    return newNormal;
}

layout(push_constant) uniform pc {
    layout(offset = 64) uint materialIdx;
} push_constants;

void main()
{
    outPos = inPos;

    Material material = matUniform.materials[push_constants.materialIdx];
    if (material.hasTexture == 1) {
        outAlbedo = texture(textSampler[material.textureIdx], inTextCoords);
    } else {
        outAlbedo = material.diffuseColor;
    }

    vec4 Opacity = vec4(outAlbedo.a,outAlbedo.a,outAlbedo.a,1);
    if(material.OpacityFactor != 1) Opacity = vec4(material.OpacityFactor, material.OpacityFactor, material.OpacityFactor, 1);
    if(material.hasOpacityMap > 0 && material.OpacityMapIdx < MAX_TEXTURES){
        Opacity = texture(textSampler[material.OpacityMapIdx], inTextCoords);
    }
    outOpacity = Opacity;

    float opacityf = Opacity.x + Opacity.y + Opacity.z;
    opacityf = opacityf/3;

    outAlbedo = vec4(outAlbedo.rgb, opacityf);

    if(outAlbedo.a < 0.5) discard;

    mat3 TBN = mat3(inTangent, inBitangent, inNormal);
    vec3 newNormal = calcNormal(material, inNormal, inTextCoords, TBN);
    outNormal = vec4(newNormal, 1.0f);

    float ao = 0.5f;
    float roughnessFactor = 0.0f;
    float metallicFactor = 0.0f;
    if (material.hasRoughMap > 0) {
        vec4 metRoughValue = texture(textSampler[material.roughMapIdx], inTextCoords);
        roughnessFactor = metRoughValue.g;
        metallicFactor = metRoughValue.b;
    } else {
        roughnessFactor = material.roughnessFactor;
        metallicFactor = material.metallicFactor;
    }

    vec4 emissive = material.emissiveColour;
    if (material.hasEmissiveMap > 0 && material.emissiveMapIdx < MAX_TEXTURES) {
        emissive = texture(textSampler[material.emissiveMapIdx], inTextCoords);
    }
    outEmissive = emissive;

    vec4 Translucency = vec4(material.translucencyFactor,material.translucencyFactor,material.translucencyFactor,1);
    if(material.hasTranslucencyMap > 0 && material.translucencyMapIdx < MAX_TEXTURES){
        Translucency = texture(textSampler[material.translucencyMapIdx], inTextCoords);
    }
    outTranslucency = Translucency;

    outPBR = vec4(ao, roughnessFactor, metallicFactor, 1.0f);

}