#include "../config/pathan_config.h"
/*
 * Copyright (c) 2001, DecisionSoft Limited All rights reserved.
 * Please see LICENSE.TXT for more information.
 */

#include <pathan/functions/FunctionRoundHalfToEven.hpp>
#include <pathan/ATDecimalOrDerived.hpp>
#include <pathan/DynamicContext.hpp>
#include <pathan/internal/factory/DatatypeFactory.hpp>

const XMLCh FunctionRoundHalfToEven::name[] = { XERCES_CPP_NAMESPACE_QUALIFIER chLatin_r, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_o, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_u, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_n, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_d, XERCES_CPP_NAMESPACE_QUALIFIER chDash, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_h, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_a, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_l, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_f, XERCES_CPP_NAMESPACE_QUALIFIER chDash, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_t, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_o, XERCES_CPP_NAMESPACE_QUALIFIER chDash, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_e, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_v, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_e, XERCES_CPP_NAMESPACE_QUALIFIER chLatin_n, XERCES_CPP_NAMESPACE_QUALIFIER chNull };

/*
 * fn:round-half-to-even($arg as numeric?) as numeric?
 * fn:round-half-to-even($arg as numeric?, $precision as xs:integer) as numeric?
 */

FunctionRoundHalfToEven::FunctionRoundHalfToEven(const VectorOfDataItems &args, XPath2MemoryManager* memMgr)
  : NumericFunction(name,1, 2, "anySimpleType?, integer", args, memMgr)
{
}

Sequence FunctionRoundHalfToEven::collapseTreeInternal(DynamicContext* context, int flags) const
{
	XPath2MemoryManager* memMgr = context->getMemoryManager();

  Sequence arg = getParamNumber(1, context);
    
  //If the argument is the empty sequence, the empty sequence is returned.

  if(arg.isEmpty()) {
    return Sequence(memMgr);
  }

  const Numeric* numericArg = (const Numeric*)arg.first();
  if(isNaN(numericArg))
    return Sequence(numericArg, memMgr);
  if(isINF(numericArg))
    return Sequence(numericArg, memMgr);
  const ATDecimalOrDerived* precision = NULL;
  if (getNumArgs() > 1) {
    Sequence precisionArg = getParamNumber(2,context);
    precision = (const ATDecimalOrDerived*)precisionArg.first();
  }
  else
    precision = DatatypeFactory::POD2AT::createInteger(memMgr, 0, context);
  
  return Sequence(numericArg->roundHalfToEven(precision, context), memMgr);
}