package tudelft.healthpsychology.traumaontologies.owltree;

import java.io.File;
import java.util.Collection;
import java.util.List;
import java.util.stream.Collectors;

import org.semanticweb.owlapi.apibinding.OWLManager;
import org.semanticweb.owlapi.model.OWLClass;
import org.semanticweb.owlapi.model.OWLOntologyCreationException;

import tudelft.healthpsychology.traumaontologies.answerstate.OntologyNode;
import tudelft.healthpsychology.traumaontologies.answerstate.Property;
import tudelft.utilities.tree.TreeNode;

/**
 * Default implementation of {@link OntologyNode} that pulls its relations from
 * a owl file. An ontology node points to a {@link OWLClass} object in the
 * ontology.
 * 
 * The OWL Ontology must contain only trees. It is not allowed to have a node
 * with multiple parents (but multiple nodes may have no parents at all).
 */
public class OwlOntologyNode implements OntologyNode {
	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((object == null) ? 0 : object.hashCode());
		result = prime * result
				+ ((reasoner == null) ? 0 : reasoner.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		OwlOntologyNode other = (OwlOntologyNode) obj;
		if (object == null) {
			if (other.object != null)
				return false;
		} else if (!object.equals(other.object))
			return false;
		if (reasoner == null) {
			if (other.reasoner != null)
				return false;
		} else if (!reasoner.equals(other.reasoner))
			return false;
		return true;
	}

	private final OwlTreeReasoner reasoner;
	private OWLClass object;

	public OwlOntologyNode(OWLClass object, OwlTreeReasoner reasoner) {
		this.reasoner = reasoner;
		this.object = object;
	}

	public OwlOntologyNode(String nodename, OwlTreeReasoner reas) {
		this(reas.getObject(nodename), reas);
	}

	/**
	 * 
	 * @param rootname the name of the root {@link OWLClass} in the ontology.
	 *                 This is the name after the "#" in the full object iri.
	 *                 This does not need to be a root node but usually it will
	 *                 be.
	 * @param owlfile  the owlfile to read the node from
	 * @throws OWLOntologyCreationException
	 */
	public static OwlOntologyNode fromFile(String rootname, File owlfile)
			throws OWLOntologyCreationException {
		OwlTreeReasoner reas = new OwlTreeReasoner(
				OWLManager.createOWLOntologyManager()
						.loadOntologyFromOntologyDocument(owlfile));
		return new OwlOntologyNode(reas.getObject(rootname), reas);
	}

	@Override
	public List<Property> getAttribute() {
		return reasoner.getProperties(object).stream()
				.map(axiom -> new OwlProperty(axiom, reasoner))
				.collect(Collectors.toList());
	}

	@Override
	public OwlOntologyNode getChild(String label) {
		for (OWLClass obj : reasoner.getChildren(object)) {
			if (obj.toStringID().endsWith(label)) // TEST. bit hacky?
				return new OwlOntologyNode(obj, reasoner);
		}
		return null;
	}

	@Override
	public List<? extends TreeNode<String, Collection<Property>>> getChildren() {
		return reasoner.getChildren(object).stream()
				.map(owlclass -> new OwlOntologyNode(owlclass, reasoner))
				.collect(Collectors.toList());
	}

	@Override
	public String getLabel() {
		return object.getIRI().getShortForm();
	}

	@Override
	public List<OntologyNode> getChildren(int depth) {
		return reasoner.getChildren(object, depth).stream()
				.map(obj -> new OwlOntologyNode(obj, reasoner))
				.collect(Collectors.toList());
	}

	@Override
	public OntologyNode getParent() {
		OWLClass parent = reasoner.getParent(object);
		if (parent == null)
			return null;
		return new OwlOntologyNode(parent, reasoner);
	}

	@Override
	public String toString() {
		return "Node[" + object + "]";
	}

}