/*
    * SPDX-FileCopyrightText: none
    * SPDX-License-Identifier: CC0-1.0
    */
   
   package dev.metaschema.core.model.constraint.impl;
   
   import java.util.regex.Pattern;
   
  import dev.metaschema.core.datatype.markup.MarkupMultiline;
  import dev.metaschema.core.metapath.IMetapathExpression;
  import dev.metaschema.core.model.constraint.IIndexConstraint;
  import dev.metaschema.core.model.constraint.IIndexHasKeyConstraint;
  import dev.metaschema.core.model.constraint.IKeyField;
  import dev.metaschema.core.model.constraint.IUniqueConstraint;
  import edu.umd.cs.findbugs.annotations.NonNull;
  import edu.umd.cs.findbugs.annotations.Nullable;
  
  /**
   * The default implementation of an index that can support the
   * {@link IIndexConstraint}, {@link IIndexHasKeyConstraint}, and
   * {@link IUniqueConstraint}.
   */
  public class DefaultKeyField implements IKeyField {
  
    @Nullable
    private final Pattern pattern;
    @NonNull
    private final IMetapathExpression target;
    @Nullable
    private final MarkupMultiline remarks;
  
    /**
     * Construct a new key field based on the provided target. An optional pattern
     * can be used to extract a portion of the resulting key value.
     *
     * @param target
     *          a Metapath expression identifying the target of the key field
     * @param pattern
     *          an optional used to extract a portion of the resulting key value
     * @param remarks
     *          optional remarks describing the intent of the constraint
     */
    public DefaultKeyField(
        @NonNull IMetapathExpression target,
        @Nullable Pattern pattern,
        @Nullable MarkupMultiline remarks) {
      this.pattern = pattern;
      this.target = target;
      this.remarks = remarks;
    }
  
    @Override
    public Pattern getPattern() {
      return pattern;
    }
  
    @Override
    public IMetapathExpression getTarget() {
      return target;
    }
  
    @Override
    public MarkupMultiline getRemarks() {
      return remarks;
    }
  }