package gw.currency

uses gw.pl.currency.MonetaryAmount
uses gw.util.GosuObjectUtil

uses java.util.Arrays

@ReadOnly
enhancement GWArrayMonetaryAmountSumCoreEnhancement<T> : T[] {

  /**
   * Return the average of the values of the target of the mapper argument,
   *   which must all be of the same currency as specified.
   */
  reified function average( currency : Currency, select:block(elt:T):MonetaryAmount) : MonetaryAmount {
    return getList().average( currency, select )
  }

  /**
   * Sums up the values of the target of the mapper argument,
   *   which must all be of the same currency as specified.
   */
  function sum( currency : Currency, mapper(elt:T) : MonetaryAmount ) : MonetaryAmount {
    return getList().sum( currency, mapper )
  }

  // Cribbed from CoreArrayEnhancement.gsx:fastList()
  // Can't directly use fastList() as it is an internal function
  private function getList() : java.util.List<T> {
    if (GosuObjectUtil.isJavaReferenceArray(this)) {
      return Arrays.asList<T>(this)
    } else {
      return this.toList()
    }
  }
}