package org.simantics.structural2;

import java.util.Collection;
import java.util.Set;

import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.variable.Variable;
import org.simantics.structural2.variables.Connection;
import org.simantics.structural2.variables.ConnectionBrowser;
import org.simantics.structural2.variables.VariableConnectionPointDescriptor;

import gnu.trove.set.hash.THashSet;

public class ConnectionImpl implements Connection {

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((predicate == null) ? 0 : predicate.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;
		ConnectionImpl other = (ConnectionImpl) obj;
		if (predicate == null) {
			if (other.predicate != null)
				return false;
		} else if (!predicate.equals(other.predicate))
			return false;
		return true;
	}

	final private Resource predicate;
	
	public ConnectionImpl(Resource predicate) {
		this.predicate = predicate;
	}
	
	@Override
	public Collection<Variable> getConnectionPoints(ReadGraph graph, Variable component, Resource relationType) throws DatabaseException {
	    Set<Variable> result = new THashSet<Variable>();
	    for(VariableConnectionPointDescriptor desc : ConnectionBrowser.flatten(graph, component, predicate, relationType)) {
	    	result.add(desc.getVariable(graph));
	    }
	    return result;
	}
	
	@Override
	public Collection<String> getConnectionPointURIs(ReadGraph graph, Variable component, Resource relationType) throws DatabaseException {
	    Set<String> result = new THashSet<String>();
	    for(VariableConnectionPointDescriptor desc : ConnectionBrowser.flatten(graph, component, predicate, relationType)) {
	    	result.add(desc.getURI(graph));
	    }
	    return result;
	}

	@Override
	public Collection<VariableConnectionPointDescriptor> getConnectionPointDescriptors(ReadGraph graph, Variable component, Resource relationType) throws DatabaseException {
	    return ConnectionBrowser.flatten(graph, component, predicate, relationType);
	}

}