/*-
    * #%L
    * prolobjectlink-jpi-tuprolog
    * %%
    * Copyright (C) 2020 - 2021 Prolobjectlink Project
    * %%
    * This program is free software: you can redistribute it and/or modify
    * it under the terms of the GNU Lesser General Public License as
    * published by the Free Software Foundation, either version 2.1 of the
   * License, or (at your option) any later version.
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Lesser Public License for more details.
   * 
   * You should have received a copy of the GNU General Lesser Public
   * License along with this program.  If not, see
   * <http://www.gnu.org/licenses/lgpl-2.1.html>.
   * #L%
   */
  package io.github.prolobjectlink.prolog.tuprolog;
  
  import static io.github.prolobjectlink.prolog.PrologTermType.OBJECT_TYPE;
  
  import alice.tuprolog.Struct;
  import alice.tuprolog.Term;
  import alice.tuprolog.lib.InvalidObjectIdException;
  import alice.tuprolog.lib.OOLibrary;
  import io.github.prolobjectlink.prolog.PrologError;
  import io.github.prolobjectlink.prolog.PrologProvider;
  import io.github.prolobjectlink.prolog.PrologReference;
  import io.github.prolobjectlink.prolog.PrologTerm;
  
  public class TuPrologReference extends TuPrologTerm implements PrologReference {
  
  	private static final OOLibrary OO_LIBRARY = new OOLibrary();
  
  	TuPrologReference(PrologProvider provider, Term reference) {
  		super(OBJECT_TYPE, provider, reference);
  	}
  
  	TuPrologReference(PrologProvider provider, Object reference) {
  		super(OBJECT_TYPE, provider, set(reference));
  	}
  
  	public Class<?> getReferenceType() {
  		return getObject().getClass();
  	}
  
  	public int getArity() {
  		Struct object = (Struct) value;
  		return object.getArity();
  	}
  
  	public String getFunctor() {
  		Struct object = (Struct) value;
  		return object.getName();
  	}
  
  	public PrologTerm[] getArguments() {
  		return new PrologTerm[0];
  	}
  
  	public Object getObject() {
  		return get((Struct) value);
  	}
  
  	static Struct set(Object reference) {
  		return OO_LIBRARY.register(reference);
  	}
  
  	static Object get(Struct id) {
  		try {
  			return OO_LIBRARY.getRegisteredObject(id);
  		} catch (InvalidObjectIdException e) {
  			throw new PrologError(e.getMessage(), e);
  		}
  	}
  
  }