// helloask.cxx (example2a)

#include <FL/Fl.H>
#include <FL/Fl_Window.h>
#include <FL/Fl_Slider.h>
#include <FL/Fl_Button.h>
#include <FL/Fl_Int_Input.h>

#include <cstdlib>

// utility to convert anthing to a string
#include <sstream>
template<typename T>
char* makestr(const T& i) {
    std::ostringstream os;
    os << i;
    std::string oss = os.str();
    char* sp = new char[oss.length()+1];
    sp[oss.copy(sp, std::string::npos)] = 0;
    return sp;
}

Fl_Int_Input* intinput;

void copy_callback(Fl_Widget*, void* v) {
  Fl_Slider* slider = (Fl_Slider*)v;
  slider->value(atoi(intinput->value()));
}

void down_callback(Fl_Widget*, void* v) {
  Fl_Slider* slider = (Fl_Slider*)v;
  slider->value(slider->value()-1);
  intinput->value(makestr(slider->value()));
}

void up_callback(Fl_Widget*, void* v) {
  Fl_Slider* slider = (Fl_Slider*)v;
  slider->value(slider->value()+1);
  intinput->value(makestr(slider->value()));
}

void slider_callback(Fl_Widget* w, void*) {
  Fl_Slider* slider = (Fl_Slider*)w;
  intinput->value(makestr(slider->value()));
}

void exit_callback(Fl_Widget *, void *) {
  exit(0);
}

int main( ) {
  Fl_Window window(320, 90);
  window.begin();
  Fl_Int_Input intinput(10,10,100,20);
  ::intinput = &intinput;
  intinput.value("0");
  Fl_Button copy_button(110, 10, 100, 20, "copy to slider");

  Fl_Slider slider(10,35,300,20);
  slider.type(FL_HORIZONTAL);
  slider.callback(slider_callback);
  copy_button.callback(copy_callback, &slider);
  slider.range(-10,10);
  slider.step(1);
  slider.value(0);

  Fl_Button down_button(50,60,50,20,"down");
  down_button.callback(down_callback, &slider);
  Fl_Button up_button(150,60,50,20,"up");
  up_button.callback(up_callback, &slider);
  Fl_Button exit_button(250,60,50,20,"exit");
  exit_button.callback(exit_callback);
  
  window.end();
  window.show();
  return Fl::run();
}