#include <XCEngine/Resources/Mesh/Mesh.h>
#include <XCEngine/Resources/Material/Material.h>
#include <XCEngine/Resources/Texture/Texture.h>
#include <cstring>

namespace XCEngine {
namespace Resources {

Mesh::Mesh() = default;
Mesh::~Mesh() = default;

void Mesh::Release() {
    m_vertexData.Clear();
    m_indexData.Clear();
    m_sections.Clear();
    m_materials.Clear();
    m_textures.Clear();
    m_vertexCount = 0;
    m_vertexStride = 0;
    m_attributes = VertexAttribute::Position;
    m_indexCount = 0;
    m_use32BitIndex = false;
    m_bounds = Math::Bounds();
    UpdateMemorySize();
    SetInvalid();
}

void Mesh::SetVertexData(const void* data, size_t size, Core::uint32 vertexCount,
                        Core::uint32 vertexStride, VertexAttribute attributes) {
    m_vertexCount = vertexCount;
    m_vertexStride = vertexStride;
    m_attributes = attributes;
    
    m_vertexData.Resize(size);
    if (size > 0 && data != nullptr) {
        std::memcpy(m_vertexData.Data(), data, size);
    }

    UpdateMemorySize();
}

void Mesh::SetIndexData(const void* data, size_t size, Core::uint32 indexCount, bool use32Bit) {
    m_indexCount = indexCount;
    m_use32BitIndex = use32Bit;
    
    m_indexData.Resize(size);
    if (size > 0 && data != nullptr) {
        std::memcpy(m_indexData.Data(), data, size);
    }

    UpdateMemorySize();
}

void Mesh::AddSection(const MeshSection& section) {
    m_sections.PushBack(section);
    UpdateMemorySize();
}

void Mesh::AddMaterial(Material* material) {
    m_materials.PushBack(material);
    UpdateMemorySize();
}

void Mesh::AddTexture(Texture* texture) {
    m_textures.PushBack(texture);
    UpdateMemorySize();
}

Material* Mesh::GetMaterial(Core::uint32 index) const {
    if (index >= m_materials.Size()) {
        return nullptr;
    }
    return m_materials[index];
}

void Mesh::UpdateMemorySize() {
    m_memorySize = m_vertexData.Size() +
                   m_indexData.Size() +
                   m_sections.Size() * sizeof(MeshSection) +
                   m_materials.Size() * sizeof(Material*) +
                   m_textures.Size() * sizeof(Texture*);

    for (const Material* material : m_materials) {
        if (material != nullptr) {
            m_memorySize += material->GetMemorySize();
        }
    }

    for (const Texture* texture : m_textures) {
        if (texture != nullptr) {
            m_memorySize += texture->GetMemorySize();
        }
    }
}

} // namespace Resources
} // namespace XCEngine