/**
    * 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.commons.rdf.rdf4j.impl;
  
  import java.util.Collections;
  import java.util.ConcurrentModificationException;
  import java.util.HashSet;
  import java.util.Objects;
  import java.util.Set;
  import java.util.UUID;
  import java.util.stream.Stream;
  
  import org.apache.commons.rdf.api.BlankNodeOrIRI;
  import org.apache.commons.rdf.api.IRI;
  import org.apache.commons.rdf.api.RDFTerm;
  import org.apache.commons.rdf.api.Triple;
  import org.apache.commons.rdf.rdf4j.ClosableIterable;
  import org.apache.commons.rdf.rdf4j.RDF4JBlankNodeOrIRI;
  import org.apache.commons.rdf.rdf4j.RDF4JGraph;
  import org.apache.commons.rdf.rdf4j.RDF4JTriple;
  import org.eclipse.rdf4j.common.iteration.Iterations;
  import org.eclipse.rdf4j.model.Resource;
  import org.eclipse.rdf4j.model.Statement;
  import org.eclipse.rdf4j.model.Value;
  import org.eclipse.rdf4j.repository.Repository;
  import org.eclipse.rdf4j.repository.RepositoryConnection;
  import org.eclipse.rdf4j.repository.RepositoryResult;
  
  class RepositoryGraphImpl extends AbstractRepositoryGraphLike<Triple> implements RDF4JGraph {
  
      private final Resource[] contextMask;
  
      RepositoryGraphImpl(final Repository repository, final UUID salt, final boolean handleInitAndShutdown, final boolean includeInferred,
              final Resource... contextMask) {
          super(repository, salt, handleInitAndShutdown, includeInferred);
          this.contextMask = Objects.requireNonNull(contextMask);
      }
  
      @Override
      public void add(final Triple tripleLike) {
          final Statement statement = rdf4jTermFactory.asStatement(tripleLike);
          try (RepositoryConnection conn = getRepositoryConnection()) {
              conn.add(statement, contextMask);
              conn.commit();
          }
      }
  
      @Override
      public boolean contains(final Triple tripleLike) {
          final Statement statement = rdf4jTermFactory.asStatement(tripleLike);
          try (RepositoryConnection conn = getRepositoryConnection()) {
              return conn.hasStatement(statement, includeInferred, contextMask);
          }
      }
  
      @Override
      public void remove(final Triple tripleLike) {
          final Statement statement = rdf4jTermFactory.asStatement(tripleLike);
          try (RepositoryConnection conn = getRepositoryConnection()) {
              conn.remove(statement, contextMask);
              conn.commit();
          }
      }
  
      @Override
      public void clear() {
          try (RepositoryConnection conn = getRepositoryConnection()) {
              conn.clear(contextMask);
              conn.commit();
          }
      }
  
      @Override
      public long size() {
          if (!includeInferred && contextMask.length == 0) {
              try (RepositoryConnection conn = getRepositoryConnection()) {
                  return conn.size();
              }
          }
          try (Stream<RDF4JTriple> stream = stream()) {
              return stream.count();
          }
      }
  
     @Override
     public void add(final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object) {
         final Resource subj = (Resource) rdf4jTermFactory.asValue(subject);
         final org.eclipse.rdf4j.model.IRI pred = (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate);
         final Value obj = rdf4jTermFactory.asValue(object);
         try (RepositoryConnection conn = getRepositoryConnection()) {
             conn.add(subj, pred, obj, contextMask);
             conn.commit();
         }
     }
 
     @Override
     public boolean contains(final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object) {
         final Resource subj = (Resource) rdf4jTermFactory.asValue(subject);
         final org.eclipse.rdf4j.model.IRI pred = (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate);
         final Value obj = rdf4jTermFactory.asValue(object);
         try (RepositoryConnection conn = getRepositoryConnection()) {
             return conn.hasStatement(subj, pred, obj, includeInferred, contextMask);
         }
     }
 
     @Override
     public void remove(final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object) {
         final Resource subj = (Resource) rdf4jTermFactory.asValue(subject);
         final org.eclipse.rdf4j.model.IRI pred = (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate);
         final Value obj = rdf4jTermFactory.asValue(object);
         try (RepositoryConnection conn = getRepositoryConnection()) {
             conn.remove(subj, pred, obj, contextMask);
             conn.commit();
         }
     }
 
     @Override
     public ClosableIterable<Triple> iterate() throws ConcurrentModificationException, IllegalStateException {
         return iterate(null, null, null);
     }
 
     @Override
     public ClosableIterable<Triple> iterate(final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object)
             throws ConcurrentModificationException, IllegalStateException {
         final Resource subj = (Resource) rdf4jTermFactory.asValue(subject);
         final org.eclipse.rdf4j.model.IRI pred = (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate);
         final Value obj = rdf4jTermFactory.asValue(object);
         return new ConvertedStatements<>(this::getRepositoryConnection, rdf4jTermFactory::asTriple, subj, pred,
                 obj, contextMask);
     }
 
     @Override
     public Stream<RDF4JTriple> stream() {
         return stream(null, null, null);
     }
 
     @Override
     public Stream<RDF4JTriple> stream(final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object) {
         final Resource subj = (Resource) rdf4jTermFactory.asValue(subject);
         final org.eclipse.rdf4j.model.IRI pred = (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate);
         final Value obj = rdf4jTermFactory.asValue(object);
 
         // NOTE: We can't do the usual try..with closing of the
         // RepositoryConnection here as it will have to be closed outside
         // by the user of the returned stream
         final RepositoryConnection conn = getRepositoryConnection();
         Stream<RDF4JTriple> stream = null;
         try {
             final RepositoryResult<Statement> statements = conn.getStatements(subj, pred, obj, includeInferred, contextMask);
             // NOTE: Iterations.stream should close RepositoryResult as long as
             // our caller closes the stream
             stream = Iterations.stream(statements).map(this::asTripleLike);
         } finally {
             if (stream == null) {
                 // Some exception before we made the stream, close connection
                 // here
                 conn.close();
             }
         }
         // Make sure the RepositoryConnection is closed
         return stream == null ? null : stream.onClose(conn::close);
     }
 
     @Override
     protected RDF4JTriple asTripleLike(final Statement statement) {
         return rdf4jTermFactory.asTriple(statement);
     }
 
     @Override
     public Set<RDF4JBlankNodeOrIRI> getContextMask() {
         final Set<RDF4JBlankNodeOrIRI> mask = new HashSet<>();
         for (final Resource s : contextMask) {
             mask.add(rdf4jTermFactory.asRDFTerm(s));
         }
         return Collections.unmodifiableSet(mask);
     }
 
 }