/*
    * SPDX-FileCopyrightText: none
    * SPDX-License-Identifier: CC0-1.0
    */
   
   package dev.metaschema.core.metapath.cst.path;
   
   import java.util.stream.Stream;
   
  import dev.metaschema.core.metapath.cst.IExpressionVisitor;
  import dev.metaschema.core.metapath.item.node.IFlagNodeItem;
  import dev.metaschema.core.metapath.item.node.INodeItem;
  import dev.metaschema.core.qname.IEnhancedQName;
  import dev.metaschema.core.util.ObjectUtils;
  import edu.umd.cs.findbugs.annotations.NonNull;
  
  /**
   * A Metapath path expression that finds any child {@link IFlagNodeItem} that
   * matches the provided {@code test}.
   * <p>
   * Based on the XPath 3.1
   * <a href="https://www.w3.org/TR/xpath-31/#id-steps">step</a> syntax.
   */
  public class FlagStep
      extends AbstractStepExpression<IFlagNodeItem> {
  
    /**
     * Construct a new expression that finds any child {@link IFlagNodeItem} that
     * matches the provided {@code test}.
     *
     * @param text
     *          the parsed text of the expression
     * @param test
     *          the test to use to match
     */
    public FlagStep(@NonNull String text, @NonNull INodeTestExpression test) {
      super(text, test);
    }
  
    @Override
    public Class<IFlagNodeItem> getBaseResultType() {
      return IFlagNodeItem.class;
    }
  
    @Override
    public <RESULT, CONTEXT> RESULT accept(IExpressionVisitor<RESULT, CONTEXT> visitor, CONTEXT context) {
      return visitor.visitFlagStep(this, context);
    }
  
    @Override
    protected Stream<? extends IFlagNodeItem> getChildNodes(INodeItem focus) {
      return focus.flags();
    }
  
    @Override
    protected Stream<? extends IFlagNodeItem> getChildNodesWithName(
        INodeItem focus,
        IEnhancedQName name) {
      return ObjectUtils.notNull(Stream.ofNullable(focus.getFlagByName(name)));
    }
  }