% herramientas para el manejo de 'features' en inglés
% gabriel@ranchonotorious.org

% cargar segments
init 	
	:- 
		consult('features.pro')
	,	write_nl_list([
			'herramientas para manejo de ''features'' en inglés'
		,	'predicados:'
		,	'	display_segment(Segment+).'
		,	' 	find_segment(Segment+).'
		,	'	find_all_segments(Feature_list+, List-).'
		,	'	compare_segments(Segment_list+, Common_features-).'
		,	'	contrast_segments(Segment_1+, Segment_2+).'
		,	'	segment_superset(Segment_list+, List_superset-).'
		,	' 	segments_to_features(Segment_list+, Lists_of_features-).'
		])

.

% sobre los segmentos
compare_segments(Segment_list, Common_features)
	:-
		segments_to_features(Segment_list, Lists_of_features)
	,	common_elements_from_list(Lists_of_features, Common_features)
	.

contrast_segments(S1, S2)
	:-
		segments_to_features([S1, S2], [F1|[F2_h|[]]])
	,	diff_elements(F1, F2_h, Diff_1)
	,	diff_elements(F2_h, F1, Diff_2)

	%,	write(S1)
	,	write(S2)
	,	write(':')
	,	write(Diff_1)
	,	nl
	%,	write(S2)
	,	write(S1)
	,	write(':')
	,	write(Diff_2)
	.

segment_superset(Segment_list, List_superset)
	:-
		compare_segments(Segment_list, Common_features)
	,	find_all_segments(Common_features, List_superset)
	.

display_segment(Segment)
	:-
		segment(Segment, Features)
	,	write_nl_list([Segment|Features])
	.

find_segment(Feature_list, Segment)
	:-
		segment(Segment, Features)
	,	all_are_members(Feature_list, Features)
	.

find_all_segments(Feature_list, List)
	:-
		bagof(Segment, find_segment(Feature_list, Segment), List)
	.

segments_to_features(Segment_list, Lists_of_features)
	:-
		segments_to_features(Segment_list,[],Lists_of_features)
	.

segments_to_features([],Acumulator, Acumulator).

segments_to_features([H|List_of_segments], Acumulator, Lists_of_features)
	:-
		segment(H,Features)
	,	segments_to_features(List_of_segments, [Features|Acumulator],Lists_of_features)
	.


% manipulación de listas
member(Element, [Element|_]).
member(Element, [_|List])	
	:-
		member(Element, List)
	.

non_member(Element, List)
	:-
		not(member(Element, List))
	.

all_are_members([], _).
all_are_members([Next|List], Set)
	:-
		member(Next, Set)
	,	all_are_members(List, Set)
	.

% common_elements /2, 
common_elements(List_1,List_2,Common)
	:-
		common_elements(List_1, List_2, [], Common)
	.

common_elements([],_,[]).
common_elements(_,[],[]).

common_elements([L1_h|L1_t], L2, Acumulator, Common)
	:-
		member(L1_h, L2)
	,	common_elements(L1_t, L2, [L1_h|Acumulator], Common)
	.

common_elements([L1_h|L1_t], L2, Acumulator, Common)
	:-
		non_member(L1_h, L2)
	,	common_elements(L1_t, L2, Acumulator, Common)
	.

common_elements([L_i|[]], L2, Acumulator, [L_i|Acumulator])
	:-
		member(L_i, L2)
	.

common_elements([L_i|[]], L2, Acumulator, Acumulator)
	:-
		non_member(L_i, L2)
	.

diff_elements(L1, L2, Diff)
	:-
		diff_elements(L1, L2, [], Diff)
	.

diff_elements([Item|[]], L2, Acumulator, [Item|Acumulator])
	:-
		non_member(Item, L2)
	.

diff_elements([Item|[]], L2, Acumulator, Acumulator)
	:-
		member(Item, L2)
	.

diff_elements([L1_h|L1_t], L2, Acumulator, Diff)
	:-
		non_member(L1_h, L2)
	,	diff_elements(L1_t, L2, [L1_h|Acumulator], Diff)
	.

diff_elements([L1_h|L1_t], L2, Acumulator, Diff)
	:-
		member(L1_h, L2)
	,	diff_elements(L1_t, L2, Acumulator, Diff)
	.

% common_elements_from_list(List_of_lists, Common).
common_elements_from_list([[H|T]], [H|T]).
common_elements_from_list([[]], []).
common_elements_from_list([[H1|T1],[H2|T2]|Tail],Common)
	:-
		common_elements([H1|T1],[H2|T2], Partial)
	,	common_elements_from_list([Partial|Tail], Common)
	.

% output
write_nl_list([]).
write_nl_list([Item|Remainders])
	:-
		write(Item)
	,	nl
	,	write_nl_list(Remainders)
	.

% vim:filetype=prolog