/*
    * 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.validation;
  
  import gov.nist.secauto.metaschema.core.model.constraint.IConstraint.Level;
  import gov.nist.secauto.metaschema.core.util.CollectionUtil;
  import gov.nist.secauto.metaschema.core.util.ObjectUtils;
  
  import java.util.LinkedList;
  import java.util.List;
  import java.util.concurrent.atomic.AtomicReference;
  import java.util.stream.Stream;
  
  import edu.umd.cs.findbugs.annotations.NonNull;
  
  public final class AggregateValidationResult implements IValidationResult {
    @NonNull
    private final List<IValidationFinding> findings;
    @NonNull
    private final Level highestSeverity;
  
    private AggregateValidationResult(@NonNull List<IValidationFinding> findings, @NonNull Level highestSeverity) {
      this.findings = CollectionUtil.unmodifiableList(findings);
      this.highestSeverity = highestSeverity;
    }
  
    public static IValidationResult aggregate(@NonNull IValidationResult result) {
      return result;
    }
  
    public static IValidationResult aggregate(@NonNull IValidationResult... results) {
      Stream<? extends IValidationFinding> stream = Stream.empty();
      for (IValidationResult result : results) {
        stream = Stream.concat(stream, result.getFindings().stream());
      }
      assert stream != null;
      return aggregate(stream);
    }
  
    public static IValidationResult aggregate(@NonNull Stream<? extends IValidationFinding> findingStream) {
      AtomicReference<Level> highestSeverity = new AtomicReference<>(Level.INFORMATIONAL);
  
      List<IValidationFinding> findings = new LinkedList<>();
      findingStream.sequential().forEachOrdered(finding -> {
        findings.add(finding);
        Level severity = finding.getSeverity();
        if (highestSeverity.get().ordinal() < severity.ordinal()) {
          highestSeverity.set(severity);
        }
      });
  
      return new AggregateValidationResult(findings, ObjectUtils.notNull(highestSeverity.get()));
    }
  
    @Override
    public Level getHighestSeverity() {
      return highestSeverity;
    }
  
    @Override
    public List<? extends IValidationFinding> getFindings() {
      return findings;
    }
  
  }