/************************************************

  Belief Propagation in CLP(BN)
 
**************************************************/

:- module(clpbn_bp,
          [bp/3,
           check_if_bp_done/1,
           set_horus_flag/2,
           init_bp_solver/4,
           run_bp_solver/3,
           finalize_bp_solver/1
          ]).


:- use_module(library('clpbn/dists'),
          [dist/4,
           get_dist_domain/2,
           get_dist_domain_size/2,
           get_dist_params/2
          ]).


:- use_module(library('clpbn/display'),
         [clpbn_bind_vals/3]).


:- use_module(library('clpbn/aggregates'),
	      [check_for_agg_vars/2]).


:- use_module(library(atts)).
:- use_module(library(lists)).
:- use_module(library(charsio)).

:- use_module(horus).

:- attribute id/1.


%:- set_horus_flag(inf_alg, ve).
:- set_horus_flag(inf_alg, bn_bp).
%:- set_horus_flag(inf_alg, fg_bp).
%: -set_horus_flag(inf_alg, cbp).

:- set_horus_flag(schedule, seq_fixed).
%:- set_horus_flag(schedule, seq_random).
%:- set_horus_flag(schedule, parallel).
%:- set_horus_flag(schedule, max_residual).

:- set_horus_flag(accuracy, 0.0001).

:- set_horus_flag(max_iter, 1000).

:- set_horus_flag(use_logarithms, false).
%:- set_horus_flag(use_logarithms, true).

:- set_horus_flag(order_factor_variables, false).
%:- set_horus_flag(order_factor_variables, true).



bp([[]],_,_) :- !.
bp([QueryVars], AllVars, Output) :-
	init_bp_solver(_, AllVars, _, Network),
	run_bp_solver([QueryVars], LPs, Network),
	finalize_bp_solver(Network),
	clpbn_bind_vals([QueryVars], LPs, Output).


init_bp_solver(_, AllVars0, _, bp(BayesNet, DistIds)) :-
	check_for_agg_vars(AllVars0, AllVars),
  writeln('clpbn_vars:'),
	print_clpbn_vars(AllVars),
	assign_ids(AllVars, 0),
	get_vars_info(AllVars, VarsInfo, DistIds0),
	sort(DistIds0, DistIds),
	create_ground_network(VarsInfo, BayesNet).
	%get_extra_vars_info(AllVars, ExtraVarsInfo),
	%set_extra_vars_info(BayesNet, ExtraVarsInfo).


run_bp_solver(QueryVars, Solutions, bp(Network, DistIds)) :-
	get_dists_parameters(DistIds, DistsParams),
  set_bayes_net_params(Network, DistsParams),
	flatten_1_element_sublists(QueryVars, QueryVars1),
	vars_to_ids(QueryVars1, QueryVarsIds),
	run_other_solvers(Network, QueryVarsIds, Solutions).


finalize_bp_solver(bp(Network, _)) :-
  free_bayesian_network(Network).


assign_ids([], _).
assign_ids([V|Vs], Count) :-
	put_atts(V, [id(Count)]),
	Count1 is Count + 1,
	assign_ids(Vs, Count1).


get_vars_info([], [], []).
get_vars_info(V.Vs,
              var(VarId,DS,Ev,PIds,DistId).VarsInfo,
              DistId.DistIds) :-
	clpbn:get_atts(V, [dist(DistId, Parents)]), !,
	get_atts(V, [id(VarId)]),
	get_dist_domain_size(DistId, DS),
	get_evidence(V, Ev),
	vars_to_ids(Parents, PIds),
	get_vars_info(Vs, VarsInfo, DistIds).


get_evidence(V, Ev) :-
	clpbn:get_atts(V, [evidence(Ev)]), !.
get_evidence(_V, -1). % no evidence !!!


vars_to_ids([], []).
vars_to_ids([L|Vars], [LIds|Ids]) :-
	is_list(L), !,
	vars_to_ids(L, LIds),
	vars_to_ids(Vars, Ids).
vars_to_ids([V|Vars], [VarId|Ids]) :-
	get_atts(V, [id(VarId)]),
	vars_to_ids(Vars, Ids).


get_extra_vars_info([], []).
get_extra_vars_info([V|Vs], [v(VarId, Label, Domain)|VarsInfo]) :-
	get_atts(V, [id(VarId)]), !,
	clpbn:get_atts(V, [key(Key),dist(DistId, _)]),
	term_to_atom(Key, Label),
	get_dist_domain(DistId, Domain0),
	numbers_to_atoms(Domain0, Domain),
	get_extra_vars_info(Vs, VarsInfo).
get_extra_vars_info([_|Vs], VarsInfo) :-
	get_extra_vars_info(Vs, VarsInfo).


get_dists_parameters([],[]).
get_dists_parameters([Id|Ids], [dist(Id, Params)|DistsInfo]) :-
	get_dist_params(Id, Params),
	get_dists_parameters(Ids, DistsInfo).


numbers_to_atoms([], []).
numbers_to_atoms([Atom|L0], [Atom|L]) :-
	atom(Atom), !,
	numbers_to_atoms(L0, L).
numbers_to_atoms([Number|L0], [Atom|L]) :-
	number_atom(Number, Atom),
	numbers_to_atoms(L0, L).


flatten_1_element_sublists([],[]).
flatten_1_element_sublists([[H|[]]|T],[H|R]) :- !,
	flatten_1_element_sublists(T,R).
flatten_1_element_sublists([H|T],[H|R]) :-
	flatten_1_element_sublists(T,R).


print_clpbn_vars(Var.AllVars) :-
	clpbn:get_atts(Var, [key(Key),dist(DistId,Parents)]),
	parents_to_keys(Parents, ParentKeys),
	writeln(Var:Key:ParentKeys:DistId),
	print_clpbn_vars(AllVars).
print_clpbn_vars([]).


parents_to_keys([], []).
parents_to_keys(Var.Parents, Key.Keys) :-
	clpbn:get_atts(Var, [key(Key)]),
	parents_to_keys(Parents, Keys).