#include <glad/glad.h>
#include "OpenGLVertexArray.h"
#include "Rendering/VertexBuffer.h"
#include "Rendering/IndexBuffer.h"

namespace Donut
{
    OpenGLVertexArray::OpenGLVertexArray() 
    {
        glCreateVertexArrays(1, &m_RendererID);
    }

    OpenGLVertexArray::~OpenGLVertexArray() 
    {
        glDeleteVertexArrays(1, &m_RendererID);
    }

    void OpenGLVertexArray::Bind() const 
    {
        glBindVertexArray(m_RendererID);
    }

    void OpenGLVertexArray::Unbind() const 
    {
        glBindVertexArray(0);
    }

    void OpenGLVertexArray::AddVertexBuffer(const std::shared_ptr<VertexBuffer>& vertexBuffer) 
    {
        glBindVertexArray(m_RendererID);
        vertexBuffer->Bind();

        const auto& layout = vertexBuffer->GetLayout();
        for (const auto& element : layout.GetElements()) 
        {
            glEnableVertexAttribArray(m_VertexBufferIndex);
            glVertexAttribPointer(m_VertexBufferIndex,
                element.count,
                element.type,
                element.normalized ? GL_TRUE : GL_FALSE,
                layout.GetStride(),
                reinterpret_cast<const   void*>(static_cast<uintptr_t>(element.offset)));
            m_VertexBufferIndex++;
        }

        m_VertexBuffers.push_back(vertexBuffer);
    }

    void OpenGLVertexArray::SetIndexBuffer(const std::shared_ptr<IndexBuffer>& indexBuffer) 
    {
        glBindVertexArray(m_RendererID);
        indexBuffer->Bind();
        m_IndexBuffer = indexBuffer;
    }
};