package gw.reinsurance

uses gw.pl.currency.MonetaryAmount

uses java.math.BigDecimal

class NullSafeMath {

  static function nsAdd(arg1 : MonetaryAmount, arg2 : MonetaryAmount) : MonetaryAmount {
    return (arg1 == null || arg2 == null ? null : arg1 + arg2)  
  }
  
  static function nsSub(arg1 : MonetaryAmount, arg2 : MonetaryAmount) : MonetaryAmount {
    return (arg1 == null || arg2 == null ? null : arg1 - arg2)  
  }
  
  static function nsMult(arg1 : BigDecimal, arg2 : BigDecimal) : BigDecimal {
    return (arg1 == null || arg2 == null ? null : arg1 * arg2)  
  }
  
  static function nsDiv(arg1 : BigDecimal, arg2 : BigDecimal) : BigDecimal {
    return (arg1 == null || arg2 == null ? null : arg1 / arg2)  
  }
  
  static function nsSum<T>(arr : T[], mapper : block(obj : T) : BigDecimal) : BigDecimal {
    var sum = BigDecimal.ZERO
    for (elt in arr) {
      var arg = mapper(elt)
      if (arg == null) {
        return null  
      }
      sum = sum + arg
    }
    
    return sum
  }

}