/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.jena.fuseki.access;

import java.util.Collection;
import java.util.function.Predicate;

import org.apache.jena.graph.Node;
import org.apache.jena.query.Query;
import org.apache.jena.query.QueryExecution;
import org.apache.jena.query.QueryExecutionFactory;
import org.apache.jena.sparql.core.DatasetGraph;
import org.apache.jena.sparql.core.Quad;

/** A {@link SecurityContext} that allows access to the default graph but not named graphs. */
public class SecurityContextAllowNamedGraphs implements SecurityContext {

    public SecurityContextAllowNamedGraphs() {}

    @Override
    public Collection<Node> visibleGraphs() {
        // null means "all".
        return null;
    }

    @Override
    public boolean visableDefaultGraph() { return true; }

    @Override
    public QueryExecution createQueryExecution(Query query, DatasetGraph dsg) {

        return QueryExecutionFactory.create(query, dsg);
    }

    /**
     * Quad filter to reflect the security policy of this {@link SecurityContextAllowNamedGraphs}. It is
     * better to call {@link #createQueryExecution(Query, DatasetGraph)} which may be more
     * efficient.
     */
    @Override
    public Predicate<Quad> predicateQuad() { return q-> ! Quad.isDefaultGraph(q.getGraph()); }
}
