/**
    * 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.ConcurrentModificationException;
  import java.util.Optional;
  import java.util.UUID;
  import java.util.stream.Stream;
  
  import org.apache.commons.rdf.api.BlankNodeOrIRI;
  import org.apache.commons.rdf.api.Graph;
  import org.apache.commons.rdf.api.IRI;
  import org.apache.commons.rdf.api.Quad;
  import org.apache.commons.rdf.api.RDFTerm;
  import org.apache.commons.rdf.rdf4j.ClosableIterable;
  import org.apache.commons.rdf.rdf4j.RDF4JDataset;
  import org.apache.commons.rdf.rdf4j.RDF4JQuad;
  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 RepositoryDatasetImpl extends AbstractRepositoryGraphLike<Quad> implements RDF4JDataset {
  
      RepositoryDatasetImpl(final Repository repository, final UUID salt, final boolean handleInitAndShutdown, final boolean includeInferred) {
          super(repository, salt, handleInitAndShutdown, includeInferred);
      }
  
      @Override
      public void add(final Quad tripleLike) {
          final Statement statement = rdf4jTermFactory.asStatement(tripleLike);
          try (RepositoryConnection conn = getRepositoryConnection()) {
              conn.add(statement);
              conn.commit();
          }
      }
  
      @Override
      public boolean contains(final Quad tripleLike) {
          final Statement statement = rdf4jTermFactory.asStatement(tripleLike);
          try (RepositoryConnection conn = getRepositoryConnection()) {
              return conn.hasStatement(statement, includeInferred);
          }
      }
  
      @Override
      public void remove(final Quad tripleLike) {
          final Statement statement = rdf4jTermFactory.asStatement(tripleLike);
          try (RepositoryConnection conn = getRepositoryConnection()) {
              conn.remove(statement);
              conn.commit();
          }
      }
  
      @Override
      public void clear() {
          try (RepositoryConnection conn = getRepositoryConnection()) {
              conn.clear();
              conn.commit();
          }
      }
  
      @Override
      public long size() {
          if (includeInferred) {
              // We'll need to count them all
              return stream().count();
          }
          // else: Ask directly
          try (RepositoryConnection conn = getRepositoryConnection()) {
              return conn.size();
          }
      }
  
      @Override
      public void add(final BlankNodeOrIRI graphName, final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object) {
          final Resource context = (Resource) rdf4jTermFactory.asValue(graphName);
          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, context);
             conn.commit();
         }
     }
 
     @Override
     public boolean contains(final Optional<BlankNodeOrIRI> graphName, 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);
         final Resource[] contexts = asContexts(graphName);
         try (RepositoryConnection conn = getRepositoryConnection()) {
             return conn.hasStatement(subj, pred, obj, includeInferred, contexts);
         }
     }
 
     private Resource[] asContexts(final Optional<BlankNodeOrIRI> graphName) {
         Resource[] contexts;
         if (graphName == null) {
             // no contexts == any contexts
             contexts = new Resource[0];
         } else {
             final BlankNodeOrIRI g = graphName.orElse(null);
             final Resource context = (Resource) rdf4jTermFactory.asValue(g);
             contexts = new Resource[] { context };
         }
         return contexts;
     }
 
     @Override
     public void remove(final Optional<BlankNodeOrIRI> graphName, 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);
         final Resource[] contexts = asContexts(graphName);
 
         try (RepositoryConnection conn = getRepositoryConnection()) {
             conn.remove(subj, pred, obj, contexts);
             conn.commit();
         }
     }
 
     @Override
     public Stream<RDF4JQuad> stream() {
         return stream(null, null, null, null);
     }
 
     @Override
     public Stream<RDF4JQuad> stream(final Optional<BlankNodeOrIRI> graphName, 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);
         final Resource[] contexts = asContexts(graphName);
 
         // 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<RDF4JQuad> stream = null;
         try {
             final RepositoryResult<Statement> statements = conn.getStatements(subj, pred, obj, includeInferred, contexts);
             // NOTE: Iterations.stream should close RepositoryResult as long as
             // our caller closes the stream
             stream = Iterations.stream(statements).map(rdf4jTermFactory::asQuad);
         } 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
     public ClosableIterable<Quad> iterate() throws ConcurrentModificationException, IllegalStateException {
         return iterate(null, null, null, null);
     }
 
     @Override
     public ClosableIterable<Quad> iterate(final Optional<BlankNodeOrIRI> graphName, final BlankNodeOrIRI subject, final IRI predicate,
             final RDFTerm object) throws ConcurrentModificationException, IllegalStateException {
         final Resource[] contexts = asContexts(graphName);
         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::asQuad, subj, pred, obj,
                 contexts);
     }
 
     @Override
     protected RDF4JQuad asTripleLike(final Statement s) {
         return rdf4jTermFactory.asQuad(s);
     }
 
     @Override
     public Graph getGraph() {
         // default context only
         // NOTE: We carry over the 'salt' as the graph's BlankNode should be
         // equal to our BlankNodes
         return new RepositoryGraphImpl(repository, salt, false, includeInferred, (Resource) null);
     }
 
     @Override
     public Optional<Graph> getGraph(final BlankNodeOrIRI graphName) {
         // NOTE: May be null to indicate default context
         final Resource context = (Resource) rdf4jTermFactory.asValue(graphName);
         // NOTE: We carry over the 'salt' as the graph's BlankNode should be
         // equal to our BlankNodes
         return Optional.of(new RepositoryGraphImpl(repository, salt, false, includeInferred, context));
     }
 
     @Override
     public Stream<BlankNodeOrIRI> getGraphNames() {
        final RepositoryConnection conn = getRepositoryConnection();
        final RepositoryResult<Resource> contexts = conn.getContextIDs();
         return Iterations.stream(contexts).map(g -> (BlankNodeOrIRI) rdf4jTermFactory.asRDFTerm(g))
                 .onClose(conn::close);
     }
 
 }