bwidgets/inc/basic_widgets/w/base/widget.hpp

#ifndef BWIDGETS_WIDGET_HPP_
#define BWIDGETS_WIDGET_HPP_

#include <basic_widgets/core/renderer.hpp>
#include <basic_widgets/core/type/size.hpp>

union SDL_Event;

struct SDL_Renderer;

namespace bwidgets::widget
{
    class Widget
    {
        protected:
            core::Renderer* _renderer    {nullptr};
            SDL_Rect        _viewport    {0, 0, 0, 0};
            SDL_Rect        _widget_area {0, 0, 0, 0};

            virtual void _handle_geometry_change(const SDL_Rect&) noexcept = 0;
            virtual void _handle_renderer_change(core::Renderer*) {}
            virtual void _handle_rendering() = 0;

        public:
            Widget* parent;

            Widget(Widget* p=nullptr) : parent(p) {}

            virtual        ~Widget() noexcept = default;
            virtual Widget* handle_event(const SDL_Event&);

            inline virtual core::Size size() const noexcept = 0;

            virtual Widget* render() final;

            virtual inline Widget* renderer(core::Renderer* r) final {
                _handle_renderer_change(r);
                _renderer = r;
                return this;
            }

            virtual inline const SDL_Rect& viewport() const noexcept final {
                return _viewport;
            }
            virtual inline Widget* viewport(const SDL_Rect& vp) noexcept final {
                _handle_geometry_change(vp);
                _viewport = vp;
                return this;
            }
    };
}

#endif