:- dynamic selector/1, resolution/1, outputdev/1.
selector(all).
resolution(50).
outputdev(user).

/* the next line generates a histogram of problems created */
show(c,N,B) :- bagof(X,
		(A,B,C,D,E,F)^vitalstats(A,B,X,C,D,E,F),Y), histog(Y,N).

/* the next line generates a histogram of problems expanded */
show(e,N,B) :- bagof(X,
		(A,B,C,D,E,F)^vitalstats(A,B,C,X,D,E,F),Y), histog(Y,N).

/* the next line generates a histogram of problem depths */
show(d,N,B) :- bagof(X,
		(A,B,C,D,E,F)^vitalstats(A,B,C,D,X,E,F),Y), histog(Y,N).

/* the next line generates a histogram of effective branches */
show(i,N,B) :- bagof(X,
		(A,B,C,D,E,F)^vitalstats(A,B,C,D,E,X,F),Y), histog(Y,N).

/* the next line generates a histogram of average branches */
show(a,N,B) :- bagof(X,
		(A,B,C,D,E,F)^vitalstats(A,B,C,D,E,F,X),Y), histog(Y,N).

show(_,_,_).

genhists :- nl, nl,
	    write('c:  number of problems created'),nl,
	    write('e:  number of problems expanded'),nl,
	    write('d:  depth of problems'),nl,
	    write('i:  effect branching factor'),nl,
	    write('a:  averave branching factor'), nl,
	    write('-------------------------------'),nl,
	    write('s:  set resolution of plots'),nl,
	    write('x:  change selection for plots, i.e., solved/~solved'),nl,
	    write('o:  change output destination'),nl,
	    write('q:  quit'),nl,
	    read(X), 
	    actions(X),
	    genhists.

actions(X) :- resolution(N), selector(S), howto(S,B), !,
	      ((nonvar(X), member(X,[c,e,d,i,a]), show(X,N,B), !)
	      ; (X == 's', changeres, !)
	      ; (X == 'x', changesel, !)
	      ; (X == 'o', changeout, !)
	      ; (X == 'q',!,fail)
	      ; (nl, nl, write('Huh?'), nl)).
	      

howto(all,_) :- !.
howto(X,X) :- !.

member(X,[X|_]).
member(X,[_|Y]) :- member(X,Y).

changeres :- write('Enter the new value for resolution:  '), nl,
	     read(X), retractall(resolution(_)), asserta(resolution(X)),
	     write('The resolution has been changed to '), write(X), nl,nl.
changesel :- write('Enter the new selector {yup, nope, all}:  '), nl,
	     read(X), member(X,[yup,nope,all]),
	     retractall(selectior(S)), asserta(selector(X)),
	     write('The selector has been changed to '), write(X), nl,nl.
changesel :- write('That is not a valid option!'), nl, nl.
changeout :- retract(outputdev(X)), 
		write('Currently the output is directed to : '),
		write(X), nl, nl,
		write('Enter the New output destination:  '), read(Y),
		asserta(outputdev(Y)).



show(e,N) :- bagof(X,
		(A,B,C,D,E,F)^vitalstats(A,B,C,X,D,E,F),Y), 
		outputdev(X), tell(X), histog(Y,N), told, tell(user).


histog(X,Div) :- outputdev(B), tell(B),
		 quisortx(X,Y,[]), Y = [Min|Tail], max([Min|Tail],Min,Max), 
			Range is Max - Min,
			Inc is Range/Div,
			Start is Min/Inc,
			Z is integer(Start),
			loopover(Inc,Z,Y),
			told, tell(user).

loopover(_,_,[]).
loopover(Inc,Z,Y) :- A is integer(Z*Inc), format('~d',A), write(':	'),
			all(A,Y,R), Z2 is Z + 1, loopover(Inc,Z2,R).

all(A,[H],R) :-  H > A, !, R = [H], nl.
all(A,[H],[]) :- write('*'). 
all(A,[H|T],R) :- H > A, !, R = [H|T], nl.
all(A,[H|T],R) :- write('*'), all(A,T,R).

max([],I,I) :- !.
max([H|T], I, Max) :- ((I >= H, max(T,I,Max),!); (max(T,H,Max),!)).

min([],I,I) :- !.
min([H|T], I, Min) :- ((I =< H, min(T,I,Min),!); (min(T,H,Min),!)).


split(H,[A|X],[A|Y],Z) :- A =< H, split(H,X,Y,Z).
split(H,[A|X],Y,[A|Z]) :- A > H, split(H,X,Y,Z).
split(_,[],[],[]).

quisortx([H|T],S,X) :-
	split(H,T,A,B), quisortx(A,S,[H|Y]), quisortx(B,Y,X).
quisortx([],X,X).