Daniel@0: /* Part of DML (Digital Music Laboratory)
Daniel@0: 	Copyright 2014-2015 Samer Abdallah, University of London
Daniel@0: 	 
Daniel@0: 	This program is free software; you can redistribute it and/or
Daniel@0: 	modify it under the terms of the GNU General Public License
Daniel@0: 	as published by the Free Software Foundation; either version 2
Daniel@0: 	of the License, or (at your option) any later version.
Daniel@0: 
Daniel@0: 	This program is distributed in the hope that it will be useful,
Daniel@0: 	but WITHOUT ANY WARRANTY; without even the implied warranty of
Daniel@0: 	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Daniel@0: 	GNU General Public License for more details.
Daniel@0: 
Daniel@0: 	You should have received a copy of the GNU General Public
Daniel@0: 	License along with this library; if not, write to the Free Software
Daniel@0: 	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Daniel@0: */
Daniel@0: 
Daniel@0: :- module(backend_rdf, 
Daniel@0:       [  rdf//3 
Daniel@0:       ,  in/5
Daniel@0:       ]).
Daniel@0: 
Daniel@0: :- use_module(library(semweb/rdf_db)).
Daniel@0: :- use_module(library(semweb/turtle)).
Daniel@0: :- use_module(library(semweb/rdf_turtle_write)).
Daniel@0: :- use_module(library(dcg_core)).
Daniel@0: 
Daniel@0: :- rdf_meta rdf(r,r,o,?,?).
Daniel@0: rdf(S,P,O) --> [rdf(S,P,O)].
Daniel@0: 
Daniel@0: :- rdf_meta to_literal(+,o).
Daniel@0: to_literal(integer(X), literal(type(xsd:integer,Y))) :- atom_number(Y,X).
Daniel@0: to_literal(float(X),   literal(type(xsd:float,Y))) :- atom_number(Y,X).
Daniel@0: to_literal(double(X),  literal(type(xsd:double,Y))) :- atom_number(Y,X).
Daniel@0: to_literal(string(X),  literal(type(xsd:string,Y))) :- atom_string(Y,X).
Daniel@0: to_literal(atom(X),literal(X)).
Daniel@0: 
Daniel@0: comp(Comp,Function,Input) -->
Daniel@0:    {once(to_literal(Input,InputLit))},
Daniel@0:    rdf(Comp,dmlcla:function,literal(Function)),
Daniel@0:    rdf(Comp,dmlcla:input,InputLit).
Daniel@0: 
Daniel@0: 
Daniel@0: inx(Triples,SS,PP,OO,_) :- 
Daniel@0:    in(Triples,S,P,O,_),
Daniel@0:    rdf_global_id(S,SS),
Daniel@0:    rdf_global_id(P,PP),
Daniel@0:    rdf_global_object(O,OO).
Daniel@0: 
Daniel@0: in(Triples,S,P,O,_) :- 
Daniel@0:    number_vars_as_uris(Triples),
Daniel@0:    member(rdf(S,P,O),Triples).
Daniel@0: 
Daniel@0: phrase_triple(Phrase,S,P,O,_) :-
Daniel@0:    phrase(Phrase,Triples),
Daniel@0:    number_vars_as_uris(Triples),
Daniel@0:    member(rdf(S,P,O),Triples).
Daniel@0: 
Daniel@0: 
Daniel@0: :- meta_predicate python_rdf(//,-).
Daniel@0: python_rdf(Input,Output) :-
Daniel@0:    phrase(Input,Triples),
Daniel@0:    number_vars_as_uris(Triples),
Daniel@0:    setup_call_cleanup(
Daniel@0:       process_create( dml('python/rdf_wrapper.py'),[],
Daniel@0:                       [ cwd(dml(python)), process(PID),
Daniel@0:                         stdin(pipe(ToScript)), stdout(pipe(FromScript))]),
Daniel@0:       (  call_cleanup(rdf_save_turtle(stream(ToScript),[expand(in(Triples)), silent(true)]), close(ToScript)),
Daniel@0:          rdf_read_turtle(stream(FromScript),Output,[base_uri('_:tmp#')])
Daniel@0:       ),
Daniel@0:       (close(FromScript), process_wait(PID,Status))
Daniel@0:    ),
Daniel@0:    debug(backend,'Process exit status was: ~q',[Status]).
Daniel@0: 
Daniel@0: number_vars_as_uris(Term) :-
Daniel@0:    term_variables(Term,Vars),
Daniel@0:    seqmap(number_var_as_uri,Vars,1,_).
Daniel@0: number_var_as_uri(Var,N,M) :-
Daniel@0:    atom_number(NN,N),
Daniel@0:    rdf_global_id(dmlcla:NN,Var),
Daniel@0:    succ(N,M).