/**
    * 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.Iterator;
  import java.util.Optional;
  import java.util.Set;
  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.RDF4J;
  import org.apache.commons.rdf.rdf4j.RDF4JTriple;
  import org.eclipse.rdf4j.model.Model;
  import org.eclipse.rdf4j.model.Resource;
  import org.eclipse.rdf4j.repository.Repository;
  
  @SuppressWarnings("PMD.UnnecessaryFullyQualifiedName") // we use fully-qualified names for clarity
  final class ModelGraphImpl implements RDF4JGraph {
  
      private final Model model;
      private final RDF4J rdf4jTermFactory;
  
      ModelGraphImpl(final Model model, final RDF4J rdf4jTermFactory) {
          this.model = model;
          this.rdf4jTermFactory = rdf4jTermFactory;
      }
  
      @Override
      public void add(final BlankNodeOrIRI subject, final org.apache.commons.rdf.api.IRI predicate, final RDFTerm object) {
          model.add((Resource) rdf4jTermFactory.asValue(subject),
                  (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate), rdf4jTermFactory.asValue(object));
      }
  
      @Override
      public void add(final Triple triple) {
          model.add(rdf4jTermFactory.asStatement(triple));
      }
  
      @Override
      public Optional<Model> asModel() {
          return Optional.of(model);
      }
  
      @Override
      public Optional<Repository> asRepository() {
          return Optional.empty();
      }
  
      @Override
      public void clear() {
          model.clear();
      }
  
      @Override
      public boolean contains(final BlankNodeOrIRI subject, final org.apache.commons.rdf.api.IRI predicate, final RDFTerm object) {
          return model.contains((Resource) rdf4jTermFactory.asValue(subject),
                  (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate), rdf4jTermFactory.asValue(object));
      }
  
      @Override
      public boolean contains(final Triple triple) {
          return model.contains(rdf4jTermFactory.asStatement(triple));
      }
  
      @Override
      public void remove(final BlankNodeOrIRI subject, final org.apache.commons.rdf.api.IRI predicate, final RDFTerm object) {
          model.remove((Resource) rdf4jTermFactory.asValue(subject),
                  (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate), rdf4jTermFactory.asValue(object));
      }
  
      @Override
      public void remove(final Triple triple) {
          model.remove(rdf4jTermFactory.asStatement(triple));
      }
  
      @Override
     public long size() {
         final int size = model.size();
         if (size < Integer.MAX_VALUE) {
             return size;
         }
         // TODO: Check if this can really happen with RDF4J models
         // Collection.size() can't help us, we'll have to count
         return model.parallelStream().count();
     }
 
     @Override
     public Stream<RDF4JTriple> stream() {
         return model.parallelStream().map(rdf4jTermFactory::asTriple);
     }
 
     @Override
     public Stream<RDF4JTriple> stream(final BlankNodeOrIRI subject, final org.apache.commons.rdf.api.IRI predicate,
             final RDFTerm object) {
         return model.filter((Resource) rdf4jTermFactory.asValue(subject),
                 (org.eclipse.rdf4j.model.IRI) rdf4jTermFactory.asValue(predicate), rdf4jTermFactory.asValue(object))
                 .parallelStream().map(rdf4jTermFactory::asTriple);
     }
 
     @Override
     public Set<RDF4JBlankNodeOrIRI> getContextMask() {
         // ModelGraph always do the unionGraph
         return Collections.emptySet();
         // TODO: Should we support contextMask like in RepositoryGraphImpl?
     }
 
     @Override
     public ClosableIterable<Triple> iterate(final BlankNodeOrIRI subject, final IRI predicate, final RDFTerm object) {
         return new ClosableIterable<Triple>() {
             @SuppressWarnings("unchecked")
             @Override
             public Iterator<Triple> iterator() {
                 // double-cast to fight Java generics..
                 final Stream<? extends Triple> s = stream(subject, predicate, object);
                 return (Iterator<Triple>) s.iterator();
             }
 
             @Override
             public void close() throws Exception {
                 // no-op as Model don't have transaction
             }
         };
     }
 
     @Override
     public ClosableIterable<Triple> iterate() throws ConcurrentModificationException, IllegalStateException {
         return iterate(null, null, null);
     }
 
 }