#include "Material.h"

material_collection_t material_collection_create(size_t size)
{
    if (size > 254)
    {
        size = 254; // Limit the count to 254 to fit in a uint8_t
    }

    material_collection_t collection = {0};
    collection.buffer = (material_t*)malloc(size * sizeof(material_t));
    collection.size = (uint8_t)size;
    return collection;
}

void material_collection_resize(material_collection_t* materials, size_t size)
{
    if (size > 254)
    {
        size = 254; // Limit the count to 254 to fit in a uint8_t
    }

    material_t* temp = realloc(materials->buffer, size * sizeof(material_t));
    if (temp != NULL)
    {
        materials->buffer = temp;
        materials->size = (uint8_t)size;
    }
}

void material_collection_free(material_collection_t* materials)
{
    if (materials->buffer != NULL)
    {
        free(materials->buffer);
        materials->buffer = NULL;
    }
}

material_t material_create(const sample_bsdf_f sample, const evaluate_bsdf_f evaluate, void* data, material_collection_t* collection)
{
    material_t material = {0};

    if (collection->count >= collection->size)
    {
        material_collection_resize(collection, collection->size * 2);
    }

    material.sample_bsdf = sample;
    material.evaluate_bsdf = evaluate;
    material.data = data;
    material.id = collection->count;

    collection->buffer[collection->count] = material;
    collection->count++;

    return material;
}

vec3s sample_material_bsdf(material_t* material, const vec3s normal, const vec3s wo, float* pdf_out)
{
    vec3s wi = glms_vec3_zero();
    if (material->sample_bsdf != NULL)
    {
        wi = material->sample_bsdf(material->data, normal, wo, pdf_out);
    }

    return wi;
}

vec3s evaluate_material_bsdf(material_t* material, const shading_context_t* context)
{
    vec3s bsdf_color = glms_vec3_zero();
    if (material->evaluate_bsdf != NULL)
    {
        bsdf_color = material->evaluate_bsdf(context, material->data);
    }

    return bsdf_color;
}