/*
    * 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.metapath;
  
  import gov.nist.secauto.metaschema.core.metapath.function.FunctionUtils;
  import gov.nist.secauto.metaschema.core.metapath.function.OperationFunctions;
  import gov.nist.secauto.metaschema.core.metapath.item.atomic.IAnyAtomicItem;
  import gov.nist.secauto.metaschema.core.metapath.item.atomic.IDateItem;
  import gov.nist.secauto.metaschema.core.metapath.item.atomic.IDateTimeItem;
  import gov.nist.secauto.metaschema.core.metapath.item.atomic.IDayTimeDurationItem;
  import gov.nist.secauto.metaschema.core.metapath.item.atomic.INumericItem;
  import gov.nist.secauto.metaschema.core.metapath.item.atomic.IYearMonthDurationItem;
  
  import edu.umd.cs.findbugs.annotations.NonNull;
  
  class Addition
      extends AbstractBasicArithmeticExpression {
  
    /**
     * An expression that sums two atomic data items.
     *
     * @param left
     *          an expression whose result is summed
     * @param right
     *          an expression whose result is summed
     */
    protected Addition(@NonNull IExpression left, @NonNull IExpression right) {
      super(left, right);
    }
  
    @Override
    public <RESULT, CONTEXT> RESULT accept(IExpressionVisitor<RESULT, CONTEXT> visitor, CONTEXT context) {
      return visitor.visitAddition(this, context);
    }
  
    /**
     * Get the sum of two atomic items.
     *
     * @param left
     *          the first item to sum
     * @param right
     *          the second item to sum
     * @return the sum of both items or an empty {@link ISequence} if either item is
     *         {@code null}
     */
    @Override
    protected IAnyAtomicItem operation(@NonNull IAnyAtomicItem left, @NonNull IAnyAtomicItem right) {
      return sum(left, right);
    }
  
    /**
     * Get the sum of two atomic items.
     *
     * @param leftItem
     *          the first item to sum
     * @param rightItem
     *          the second item to sum
     * @return the sum of both items
     */
    @SuppressWarnings({ "PMD.CyclomaticComplexity", "PMD.CognitiveComplexity" })
    @NonNull
    public static IAnyAtomicItem sum(
        @NonNull IAnyAtomicItem leftItem, // NOPMD - intentional
        @NonNull IAnyAtomicItem rightItem) {
      IAnyAtomicItem retval = null;
      if (leftItem instanceof IDateItem) {
        IDateItem left = (IDateItem) leftItem;
        if (rightItem instanceof IYearMonthDurationItem) {
          retval = OperationFunctions.opAddYearMonthDurationToDate(left, (IYearMonthDurationItem) rightItem);
        } else if (rightItem instanceof IDayTimeDurationItem) {
          retval = OperationFunctions.opAddDayTimeDurationToDate(left, (IDayTimeDurationItem) rightItem);
        }
      } else if (leftItem instanceof IDateTimeItem) {
        IDateTimeItem left = (IDateTimeItem) leftItem;
        if (rightItem instanceof IYearMonthDurationItem) {
         retval = OperationFunctions.opAddYearMonthDurationToDateTime(left, (IYearMonthDurationItem) rightItem);
       } else if (rightItem instanceof IDayTimeDurationItem) {
         retval = OperationFunctions.opAddDayTimeDurationToDateTime(left, (IDayTimeDurationItem) rightItem);
       }
     } else if (leftItem instanceof IYearMonthDurationItem) {
       IYearMonthDurationItem left = (IYearMonthDurationItem) leftItem;
       if (rightItem instanceof IDateItem) {
         retval = OperationFunctions.opAddYearMonthDurationToDate((IDateItem) rightItem, left);
       } else if (rightItem instanceof IDateTimeItem) {
         retval = OperationFunctions.opAddYearMonthDurationToDateTime((IDateTimeItem) rightItem, left);
       } else if (rightItem instanceof IYearMonthDurationItem) {
         retval = OperationFunctions.opSubtractYearMonthDurations(left, (IYearMonthDurationItem) rightItem);
       }
     } else if (leftItem instanceof IDayTimeDurationItem) {
       IDayTimeDurationItem left = (IDayTimeDurationItem) leftItem;
       if (rightItem instanceof IDateItem) {
         retval = OperationFunctions.opAddDayTimeDurationToDate((IDateItem) rightItem, left);
       } else if (rightItem instanceof IDateTimeItem) {
         retval = OperationFunctions.opAddDayTimeDurationToDateTime((IDateTimeItem) rightItem, left);
       } else if (rightItem instanceof IDayTimeDurationItem) {
         retval = OperationFunctions.opAddDayTimeDurations(left, (IDayTimeDurationItem) rightItem);
       }
     } else {
       // handle as numeric
       INumericItem left = FunctionUtils.toNumeric(leftItem);
       INumericItem right = FunctionUtils.toNumeric(rightItem);
       retval = OperationFunctions.opNumericAdd(left, right);
     }
     if (retval == null) {
       throw new UnsupportedOperationException(
           String.format("The expression '%s + %s' is not supported", leftItem.getClass().getName(),
               rightItem.getClass().getName()));
     }
     return retval;
   }
 }