Detect mouse click anywhere on screen using Gtk3 - c++

Question

I am trying to make a program that follows the mouse position and checks whether the mouse button has been pressed anywhere on the screen by only using gtk. Right now i can get the position of the mouse, however i am unable to do the latter. i did some research but i couldnt find any really good example that only used gtk to do this.
Initially i tried something similar in the code of screenshot-area-selection.c from the gnome-screenshot app which do click and drag area select, and based on my understanding there was a part of the code which took the member variable of the GdkEventButton "button" to see whether there was a button click or not, however this i couldnt get it to work
/*void check_button(GdkEventButton *event, GdkWindow *root_window, GdkDevice *prim_device){
event->device = prim_device;
event->window = root_window;
switch(event->button){
case 1:
printf("button clicked: left mouse\n");
sleep(2);
break;
case 2:
printf("button clicked: middle mouse\n");
sleep(2);
break;
case 3:
printf("button clicked: right mouse\n");
sleep(2);
break;
}
}*/
so i tried using the functions available in the gtk documents but it still doesn't display whether there was a button press or not. i just started using gtk pls helpp iam going crazy.
#include <gtk/gtk.h>
#include <stdlib.h>
//#include <unistd.h>
void check_button(GdkWindow* root_window, GdkDevice* prim_device){
switch(gdk_window_get_device_events(root_window, prim_device)){
case GDK_BUTTON_PRESS_MASK:
printf("button pressed: pressed\n");
sleep(3);
break;
case GDK_BUTTON_RELEASE_MASK:
printf("button released: released\n");
sleep(3);
break;
}
}
int main (int argc, char **argv){
gdk_init(&argc, &argv);
//GdkEventButton *event;
GdkWindow *window = gdk_get_default_root_window ();
GdkDisplay* display = gdk_display_get_default();
GdkSeat* seat = gdk_display_get_default_seat(display);
GdkDevice* device = gdk_seat_get_pointer(seat);
int x, y;
while(TRUE){
//check_button(event, window, device);
check_button(window, device);
int a, b;
a = x;
b = y;
gdk_window_get_device_position (window, device, &x, &y, NULL);
if(a != x | b != y){
system("clear");
printf("x= %d, y= %d\n",x,y);
}
}
}