package org.maltparserx.parser.algorithm.planar;
import org.maltparserx.core.exception.MaltChainedException;
import org.maltparserx.core.syntaxgraph.DependencyStructure;
import org.maltparserx.core.syntaxgraph.node.DependencyNode;
import org.maltparserx.parser.DependencyParserConfig;
import org.maltparserx.parser.Oracle;
import org.maltparserx.parser.ParserConfiguration;
import org.maltparserx.parser.history.GuideUserHistory;
import org.maltparserx.parser.history.action.GuideUserAction;
/**
* @author Carlos Gomez Rodriguez
*
*/
public class PlanarArcEagerOracle extends Oracle {
public PlanarArcEagerOracle(DependencyParserConfig manager, GuideUserHistory history) throws MaltChainedException {
super(manager, history);
setGuideName("Planar");
}
public GuideUserAction predict(DependencyStructure gold, ParserConfiguration config) throws MaltChainedException {
PlanarConfig planarConfig = (PlanarConfig)config;
DependencyStructure dg = planarConfig.getDependencyGraph();
DependencyNode stackPeek = planarConfig.getStack().peek();
int stackPeekIndex = stackPeek.getIndex();
int inputPeekIndex = planarConfig.getInput().peek().getIndex();
if (!stackPeek.isRoot() && gold.getTokenNode(stackPeekIndex).getHead().getIndex() == inputPeekIndex
&& !checkIfArcExists ( dg , inputPeekIndex , stackPeekIndex ) ) {
return updateActionContainers(Planar.LEFTARC, gold.getTokenNode(stackPeekIndex).getHeadEdge().getLabelSet());
} else if (gold.getTokenNode(inputPeekIndex).getHead().getIndex() == stackPeekIndex
&& !checkIfArcExists ( dg , stackPeekIndex , inputPeekIndex ) ) {
return updateActionContainers(Planar.RIGHTARC, gold.getTokenNode(inputPeekIndex).getHeadEdge().getLabelSet());
} else if (gold.getTokenNode(inputPeekIndex).hasLeftDependent() &&
gold.getTokenNode(inputPeekIndex).getLeftmostDependent().getIndex() < stackPeekIndex) {
return updateActionContainers(Planar.REDUCE, null);
} else if (gold.getTokenNode(inputPeekIndex).getHead().getIndex() < stackPeekIndex
&&
( !gold.getTokenNode(inputPeekIndex).getHead().isRoot() || planarConfig.getRootHandling()==PlanarConfig.NORMAL )
) {
return updateActionContainers(Planar.REDUCE, null);
} else {
return updateActionContainers(Planar.SHIFT, null);
}
}
private boolean checkIfArcExists ( DependencyStructure dg , int index1 , int index2 ) throws MaltChainedException
{
return dg.getTokenNode(index2).hasHead() && dg.getTokenNode(index2).getHead().getIndex() == index1;
}
public void finalizeSentence(DependencyStructure dependencyGraph) throws MaltChainedException {}
public void terminate() throws MaltChainedException {}
}