#include "Material/Material.h"
#include <string.h>



bool material_collection_init(uint8_t size, material_collection_t* materials)
{
    if (size > 254)
    {
        size = 254;
    }

    material_collection_t temp = {0};
    temp.buffer = (material_t*)malloc(size * sizeof(material_t));
    if (temp.buffer == NULL)
    {
        return false;
    }

    temp.size = (uint8_t)size;
    temp.count = 0;
    *materials = temp;

    return true;
}

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 = (material_t*)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_entity_t material_create(const void* properties, size_t properties_size, compute_surface_data_f surface_data, sample_bsdf_f sample, sample_bsdf_pdf_f sample_pdf, evaluate_bsdf_f evaluate, material_collection_t* collection)
{
    material_t material = {0};

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

    memcpy(material.properties, properties, properties_size);
    material.compute_surface_data = surface_data;
    material.sample_bsdf = sample;
    material.sample_bsdf_pdf = sample_pdf;
    material.evaluate_bsdf = evaluate;

    material_entity_t entity = {.id = collection->count};

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

    return entity;
}

vec3s sample_material_bsdf(const material_t* material, vec3s normal, vec3s wo, vec2s uv, uint32_t sample_index, uint32_t bounce, float* pdf_out)
{
    vec3s wi = glms_vec3_zero();
    if (material->compute_surface_data != NULL && material->sample_bsdf != NULL)
    {
        shading_context_t context =
        {
            .normal = normal,
            .wo = wo,
            .uv = uv,
        };
        wi = material->sample_bsdf(&context, material->properties, material->compute_surface_data, sample_index, bounce, pdf_out);
    }

    return wi;
}

float sample_material_bsdf_pdf(const material_t* material, vec3s normal, vec3s wo, vec3s wi, vec2s uv)
{
    float pdf = 0.0f;
    if (material->compute_surface_data != NULL && material->sample_bsdf_pdf != NULL)
    {
        shading_context_t context =
        {
            .normal = normal,
            .wo = wo,
            .wi = wi,
            .uv = uv,
        };
        pdf = material->sample_bsdf_pdf(&context, material->properties, material->compute_surface_data);
    }

    return pdf;
}

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

    return bsdf_color;
}