use gtk4 :: Widget ;
use gtk4 :: Orientation :: * ;
use gtk4 :: prelude :: * ;
use libadwaita :: Bin ;



// Convenience function to conditionally append child to a widget

pub trait OptChildExt {
	fn append_opt ( & self , child : & Option < impl IsA <Widget> > ) ;
}

impl OptChildExt for gtk4 :: Box {
	fn append_opt ( & self , child : & Option < impl IsA <Widget> > ) {
		if let Some (child) = child {
			self . append (child) ;
		}
	}
}



// The `view` macro from Relm4 as an expression instead of a variable declaration

macro_rules ! view_expr { ( $ ( $ contents : tt ) * ) => { {
	relm4_macros :: view ! { outer = $ ( $ contents ) * }
	outer
} } }



pub fn vertical_filler ( child : & impl IsA <Widget> ) -> gtk4 :: Box {
	view_expr ! {
		gtk4 :: Box {
			set_orientation : Vertical ,
			append : child ,
			append : & view_expr ! {
				Bin { set_vexpand : true }
			} ,
		}
	}
}



macro_rules ! pango_attributes { (
	$ ( scale : $ scale : expr ) ?
	$ ( , weight : $ weight : expr $ (,) ? ) ?
) => { {
	let attributes = gtk4 :: pango :: AttrList :: new () ;
	# [ allow (unused_mut) ] let mut font_description = gtk4 :: pango :: FontDescription :: new () ;

	$ ( attributes . insert ( gtk4 :: pango :: AttrFloat :: new_scale ( $ scale ) ) ; ) ?
	$ ( font_description . set_weight ( $ weight ) ; ) ?

	attributes . insert ( gtk4 :: pango :: AttrFontDesc :: new ( & font_description ) ) ;
	attributes
} } }



# [ allow (unused_imports) ] pub (crate) use {
	pango_attributes ,
	view_expr ,
} ;