attribute(send,class,"btn btn-dark") :- ok
attribute(send,class,"btn btn-disabled") :- ~ok
attribute(send,disabled,false) :- ok
attribute(send,disabled,true) :- ~ok

ok :- field(city,X) & field(name,Y) & field(email,Z) & field(affiliation,W)

select(X,Y) & ~matches(Y,"^\s*$") ==> field(X,Y)
deselect(X,Y) ==> ~field(X,Y)
select(X,Y) & field(X,Z) & ~multiple(X) ==> ~field(X,Z)
multiple(affiliation)

innerhtml(f(X),Y) :- field(X,Y)
holds(f(X),Y) :- field(X,Y)
value(X,Y) :- field(X,Y)
holds(X,Y) :- field(X,Y)

select(other,Y) & ~matches(Y,"^\s*$") ==> field(affiliation,other)
select(other,Y) & matches(Y,"^\s*$") ==> ~field(affiliation,other)
deselect(affiliation,other) & field(other,X) ==> ~field(other,X)

style(status(X),display,"") :- field(X,Y)
style(status(X),display,"none") :- countofall(Y,field(X,Y),0)

click(send) ==> submitted

style(form,display,"") :- ~submitted
style(form,display,"none") :- submitted

style(thankyou,display,"") :- submitted
style(thankyou,display,"none") :- ~submitted

click(morefeedback) ==> ~submitted
click(morefeedback) & field(notes,X) ==> ~field(notes,X)
click(morefeedback) & field(city,X) ==> ~field(city,X)