// Copyright (c) 2006 - 2008, Clark & Parsia, LLC. <http://www.clarkparsia.com>
// This source code is available under the terms of the Affero General Public License v3.
//
// Please see LICENSE.txt for full license terms, including the availability of proprietary exceptions.
// Questions, comments, or requests for clarification: licensing@clarkparsia.com
package org.mindswap.pellet.tableau.blocking;
import java.util.Iterator;
import java.util.Set;
import org.mindswap.pellet.Node;
import org.mindswap.pellet.Role;
import org.mindswap.pellet.utils.ATermUtils;
import aterm.ATerm;
import aterm.ATermAppl;
import aterm.ATermList;
/**
* @author Evren Sirin
*/
public class Block2 implements BlockingCondition {
public boolean isBlocked(BlockingContext cxt) {
for (ATermAppl av : cxt.blocker.getTypes(Node.ALL)) {
ATerm p = av.getArgument(0);
ATermAppl c = (ATermAppl) av.getArgument(1);
Role s = cxt.blocked.getABox().getRole(p);
if (p instanceof ATermList) {
ATermList chain = (ATermList) p;
if (!isBlockedByChain(cxt, chain, c))
return false;
}
else if (s.isDatatypeRole()) {
continue;
}
else {
Role invS = s.getInverse();
if (cxt.isRSuccessor(invS) && !cxt.blocked.getParent().hasType(c))
return false;
if (!s.isSimple()) {
Set<ATermList> subRoleChains = s.getSubRoleChains();
for (Iterator<ATermList> it = subRoleChains.iterator(); it.hasNext();) {
ATermList chain = it.next();
if (!isBlockedByChain(cxt, chain, c))
return false;
}
}
}
}
return true;
}
protected boolean isBlockedByChain(BlockingContext cxt, ATermList chain, ATermAppl c) {
Role firstRole = cxt.blocked.getABox().getRole(chain.getFirst());
return !cxt.getIncomingRoles().contains(firstRole.getInverse())
&& cxt.blocked.getParent().hasType(ATermUtils.makeAllValues(chain.getNext(), c));
}
}