widget.hpp

#pragma once
#include "paint_device.hpp"
#include "layoutable.hpp"
#include <SDL2/SDL.h>
#include <vector>

class KeyEvent;
class TextInputEvent;
class MouseEvent;
struct ResizeEvent;
class PaintEvent;
class Layout;
struct SDL_Window;
struct SDL_Renderer;

class Widget: public PaintDevice, public Layoutable
{
  friend class Application;
public:
  Widget(Widget *parent = nullptr);
  virtual ~Widget();
  virtual void resize(int width, int height);
  int width() const;
  void setWidth(int);
  int height() const;
  void setHeight(int);
  int left() const;
  virtual void setLeft(int);
  int top() const;
  virtual void setTop(int);
  Widget *parent() const;
  Widget *ancestor();
  void setFocus();
  void clearFocus();
  bool hasFocus();
  const std::vector<Widget *> &children() const;
  Uint32 windowId() const;
  virtual SDL_Renderer *renderer();
  virtual int gLeft() const;
  virtual int gTop() const;
  void update();
  void setLayout(Layout *);
  Layout *layout();
  const Layout *layout() const;
  virtual int maxHeight() const;
  virtual int minHeight() const;
  virtual int maxWidth() const;
  virtual int minWidth() const;
protected:
  // some of following events handlers return bool, true means event handled and does not require handling from the parent object
  virtual bool keyPressEvent(KeyEvent &);
  virtual bool keyReleaseEvent(KeyEvent &);
  virtual bool textInputEvent(TextInputEvent &);
  virtual bool mouseDoubleClickEvent(MouseEvent &);
  virtual bool mouseMoveEvent(MouseEvent &);
  virtual bool mousePressEvent(MouseEvent &);
  virtual bool mouseReleaseEvent(MouseEvent &);
  virtual void paintEvent(PaintEvent &);
  virtual void resizeEvent(ResizeEvent &);
private:
  SDL_Window *window_;
  Widget *parent_;
  std::vector<Widget *> children_;
  SDL_Renderer *renderer_;
  SDL_Texture *texture_;
  int width_;
  int height_;
  int left_;
  int top_;
  bool needRepaint_;
  Layout *layout_;
  void addChild(Widget *);
  void removeChild(Widget *);
  void internalPaint(PaintEvent &);
  void updateWithoutRedraw(); 
  Widget(const Widget &);
  Widget &operator=(const Widget &);
  bool needRepaint() const;
};