/*
    * Portions of this software was developed by employees of the National Institute
    * of Standards and Technology (NIST), an agency of the Federal Government and is
    * being made available as a public service. Pursuant to title 17 United States
    * Code Section 105, works of NIST employees are not subject to copyright
    * protection in the United States. This software may be subject to foreign
    * copyright. Permission in the United States and in foreign countries, to the
    * extent that NIST may hold copyright, to use, copy, modify, create derivative
    * works, and distribute this software and its documentation without fee is hereby
   * granted on a non-exclusive basis, provided that this notice and disclaimer
   * of warranty appears in all copies.
   *
   * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
   * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
   * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
   * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
   * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
   * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
   * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
   * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
   * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
   * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
   * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
   */
  
  package gov.nist.secauto.metaschema.core.model.constraint;
  
  import gov.nist.secauto.metaschema.core.metapath.MetapathExpression;
  import gov.nist.secauto.metaschema.core.metapath.MetapathExpression.ResultType;
  import gov.nist.secauto.metaschema.core.metapath.item.node.IDefinitionNodeItem;
  import gov.nist.secauto.metaschema.core.metapath.item.node.IModuleNodeItem;
  import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItem;
  import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItemFactory;
  import gov.nist.secauto.metaschema.core.model.IDefinition;
  import gov.nist.secauto.metaschema.core.model.IModule;
  import gov.nist.secauto.metaschema.core.model.MetaschemaException;
  import gov.nist.secauto.metaschema.core.util.ObjectUtils;
  
  import java.util.Collection;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.stream.Collectors;
  import java.util.stream.Stream;
  
  import javax.xml.namespace.QName;
  
  import edu.umd.cs.findbugs.annotations.NonNull;
  
  public interface IConstraintSet {
  
    @NonNull
    static Set<IConstraintSet> resolveConstraintSets(@NonNull Set<IConstraintSet> constraintSets) {
      return ObjectUtils.notNull(constraintSets.stream()
          .flatMap(set -> resolveConstraintSet(ObjectUtils.notNull(set)))
          .distinct()
          .collect(Collectors.toUnmodifiableSet()));
    }
  
    @NonNull
    private static Stream<IConstraintSet> resolveConstraintSet(@NonNull IConstraintSet constraintSet) {
      return ObjectUtils.notNull(Stream.concat(
          Stream.of(constraintSet),
          constraintSet.getImportedConstraintSets().stream()));
    }
  
    @NonNull
    static List<ITargetedConstaints> getTargetedConstraintsForMetaschema(
        @NonNull Set<IConstraintSet> constraintSets,
        @NonNull IModule module) {
      return ObjectUtils.notNull(resolveConstraintSets(constraintSets).stream()
          .flatMap(set -> set.getTargetedConstraintsForModule(module))
          .collect(Collectors.toUnmodifiableList()));
    }
  
    @NonNull
    Stream<ITargetedConstaints> getTargetedConstraintsForModule(@NonNull IModule module);
  
    static void applyConstraintSetToModule(
        @NonNull Set<IConstraintSet> constraintSets,
        @NonNull IModule module) throws MetaschemaException {
      Set<IConstraintSet> resolvedConstraintSets = resolveConstraintSets(constraintSets);
  
      ConstraintComposingVisitor visitor = new ConstraintComposingVisitor();
      IModuleNodeItem item = INodeItemFactory.instance().newModuleNodeItem(module);
  
      for (ITargetedConstaints targeted : getTargetedConstraintsForMetaschema(resolvedConstraintSets, module)) {
        MetapathExpression targetExpression = targeted.getTargetExpression();
        INodeItem node = targetExpression.evaluateAs(item, ResultType.NODE);
        if (node == null) {
          throw new MetaschemaException(String.format("Target not found for expression '%s' on metaschema '%s'.",
              targetExpression.getPath(),
              module.getQName()));
        } else if (node instanceof IDefinitionNodeItem) {
          IDefinition nodeDefinition = ((IDefinitionNodeItem<?, ?>) node).getDefinition();
          IModule nodeModule = nodeDefinition.getContainingModule();
          if (!module.equals(nodeModule)) {
            throw new MetaschemaException(
               String.format("Target definition '%s' in metaschema '%s' is not in the scoped metaschema '%s'.",
                   nodeDefinition.getName(),
                   nodeModule.getQName(),
                   module.getQName()));
         }
       }
       node.accept(visitor, targeted);
     }
 
   }
 
   Collection<IConstraintSet> getImportedConstraintSets();
 
   /**
    * Get the set of Metaschema scoped constraints to apply by a {@link QName}
    * formed from the Metaschema namespace and short name.
    *
    * @return the mapping of QName to scoped constraints
    */
   @NonNull
   Map<QName, List<IScopedContraints>> getScopedContraints();
 }