001/*
002 * Portions of this software was developed by employees of the National Institute
003 * of Standards and Technology (NIST), an agency of the Federal Government and is
004 * being made available as a public service. Pursuant to title 17 United States
005 * Code Section 105, works of NIST employees are not subject to copyright
006 * protection in the United States. This software may be subject to foreign
007 * copyright. Permission in the United States and in foreign countries, to the
008 * extent that NIST may hold copyright, to use, copy, modify, create derivative
009 * works, and distribute this software and its documentation without fee is hereby
010 * granted on a non-exclusive basis, provided that this notice and disclaimer
011 * of warranty appears in all copies.
012 *
013 * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
014 * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
015 * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
016 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
017 * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
018 * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
019 * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
020 * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
021 * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
022 * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
023 * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
024 * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
025 */
026
027package gov.nist.secauto.metaschema.core.metapath.function.library;
028
029import gov.nist.secauto.metaschema.core.metapath.DynamicContext;
030import gov.nist.secauto.metaschema.core.metapath.ISequence;
031import gov.nist.secauto.metaschema.core.metapath.MetapathConstants;
032import gov.nist.secauto.metaschema.core.metapath.function.FunctionUtils;
033import gov.nist.secauto.metaschema.core.metapath.function.IArgument;
034import gov.nist.secauto.metaschema.core.metapath.function.IFunction;
035import gov.nist.secauto.metaschema.core.metapath.item.IItem;
036import gov.nist.secauto.metaschema.core.metapath.item.atomic.IIntegerItem;
037import gov.nist.secauto.metaschema.core.metapath.item.atomic.IStringItem;
038import gov.nist.secauto.metaschema.core.util.ObjectUtils;
039
040import java.util.List;
041
042import edu.umd.cs.findbugs.annotations.NonNull;
043
044public class FnCompare {
045
046  @NonNull
047  static final IFunction SIGNATURE = IFunction.builder()
048      .name("compare")
049      .namespace(MetapathConstants.NS_XPATH_FUNCTIONS)
050      .deterministic()
051      .contextDependent()
052      .focusIndependent()
053      .argument(IArgument.newBuilder()
054          .name("comparand1")
055          .type(IStringItem.class)
056          .zeroOrOne()
057          .build())
058      .argument(IArgument.newBuilder()
059          .name("comparand2")
060          .type(IStringItem.class)
061          .zeroOrOne()
062          .build())
063      .returnType(IIntegerItem.class)
064      .returnZeroOrOne()
065      .functionHandler(FnCompare::execute)
066      .build();
067
068  @SuppressWarnings("unused")
069  @NonNull
070  private static ISequence<IIntegerItem> execute(
071      @NonNull IFunction function,
072      @NonNull List<ISequence<?>> arguments,
073      @NonNull DynamicContext dynamicContext,
074      IItem focus) {
075    IStringItem comparand1 = FunctionUtils.getFirstItem(
076        FunctionUtils.asType(ObjectUtils.requireNonNull(arguments.get(0))), true);
077
078    IStringItem comparand2 = FunctionUtils.getFirstItem(
079        FunctionUtils.asType(ObjectUtils.requireNonNull(arguments.get(1))), true);
080
081    ISequence<IIntegerItem> retval;
082    if (comparand1 == null || comparand2 == null) {
083      retval = ISequence.empty();
084    } else {
085      IIntegerItem result = comparand1.compare(comparand2);
086      retval = ISequence.of(result);
087    }
088    return retval;
089  }
090}