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.IAnyUriItem;
037import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItem;
038import gov.nist.secauto.metaschema.core.util.ObjectUtils;
039
040import java.net.URI;
041import java.util.List;
042
043import edu.umd.cs.findbugs.annotations.NonNull;
044import edu.umd.cs.findbugs.annotations.Nullable;
045
046/**
047 * Since a node doesn't have a base URI in Metaschema, this is an alias for the
048 * document-uri function.
049 */
050public final class FnBaseUri {
051
052  @NonNull
053  static final IFunction SIGNATURE_NO_ARG = IFunction.builder()
054      .name("base-uri")
055      .namespace(MetapathConstants.NS_XPATH_FUNCTIONS)
056      .deterministic()
057      .contextDependent()
058      .focusDependent()
059      .returnType(IAnyUriItem.class)
060      .returnOne()
061      .functionHandler(FnBaseUri::executeNoArg)
062      .build();
063
064  @NonNull
065  static final IFunction SIGNATURE_ONE_ARG = IFunction.builder()
066      .name("base-uri")
067      .namespace(MetapathConstants.NS_XPATH_FUNCTIONS)
068      .deterministic()
069      .contextIndependent()
070      .focusIndependent()
071      .argument(IArgument.newBuilder()
072          .name("arg1")
073          .type(INodeItem.class)
074          .zeroOrOne()
075          .build())
076      .returnType(IAnyUriItem.class)
077      .returnOne()
078      .functionHandler(FnBaseUri::executeOneArg)
079      .build();
080
081  private FnBaseUri() {
082    // disable construction
083  }
084
085  @SuppressWarnings("unused")
086  @NonNull
087  private static ISequence<IAnyUriItem> executeNoArg(@NonNull IFunction function,
088      @NonNull List<ISequence<?>> arguments,
089      @NonNull DynamicContext dynamicContext,
090      IItem focus) {
091    return ISequence.of(fnBaseUri(
092        FunctionUtils.requireTypeOrNull(INodeItem.class, focus)));
093  }
094
095  @SuppressWarnings("unused")
096  @NonNull
097  private static ISequence<IAnyUriItem> executeOneArg(@NonNull IFunction function,
098      @NonNull List<ISequence<?>> arguments,
099      @NonNull DynamicContext dynamicContext,
100      IItem focus) {
101
102    ISequence<? extends INodeItem> arg = FunctionUtils.asType(ObjectUtils.requireNonNull(arguments.get(0)));
103
104    INodeItem item = FunctionUtils.getFirstItem(arg, true);
105
106    return ISequence.of(fnBaseUri(item));
107  }
108
109  /**
110   * Get the base URI for the provided {@code nodeItem}.
111   * <p>
112   * Based on the XPath 3.1 <a href=
113   * "https://www.w3.org/TR/xpath-functions-31/#func-base-uri">fn:base-uri</a>
114   * function.
115   *
116   * @param nodeItem
117   *          the node to get the base URI from
118   * @return the base URI, or {@code null} if the node is either null or doesn't
119   *         have a base URI
120   */
121  @SuppressWarnings("PMD.NullAssignment") // for readability
122  @Nullable
123  public static IAnyUriItem fnBaseUri(INodeItem nodeItem) {
124    IAnyUriItem retval;
125    if (nodeItem == null) {
126      retval = null; // NOPMD - intentional
127    } else {
128      URI baseUri = nodeItem.getBaseUri();
129      retval = baseUri == null ? null : IAnyUriItem.valueOf(baseUri);
130    }
131    return retval;
132  }
133}