#include "opengl_renderer_api.h"
#include <glad/glad.h>

namespace Donut
{
    void OpenGLRendererAPI::init()
    {
        glEnable(GL_BLEND);
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glEnable(GL_DEPTH_TEST);
        glDepthFunc(GL_LESS);
        
        glEnable(GL_CULL_FACE);
        glCullFace(GL_BACK);
        glFrontFace(GL_CCW);
    }

    void OpenGLRendererAPI::set_viewport(uint32_t x, uint32_t y, uint32_t width, uint32_t height)
    {
        glViewport(x, y, width, height);
    }

    void OpenGLRendererAPI::set_clear_color(const glm::vec4& color)
    {
        glClearColor(color.r, color.g, color.b, color.a);
    }

    void OpenGLRendererAPI::clear()
    {
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    }

    void OpenGLRendererAPI::enable_depth_test()
    {
        glEnable(GL_DEPTH_TEST);
    }

    void OpenGLRendererAPI::set_face_culling(bool enabled)
    {
        if (enabled)
        {
            glEnable(GL_CULL_FACE);
            glCullFace(GL_BACK);
            glFrontFace(GL_CCW);
        }
        else
            glDisable(GL_CULL_FACE);
    }

    void OpenGLRendererAPI::draw_indexed(const std::shared_ptr<VertexArray>& vertex_array, uint32_t index_count)
    {
        uint32_t count = index_count ? index_count : vertex_array->get_index_buffer()->get_count();
        glDrawElements(GL_TRIANGLES, count, GL_UNSIGNED_INT, nullptr);
        glBindTexture(GL_TEXTURE_2D, 0);
    }
};