package au.gov.amsa.ais.message;
   
   import com.google.common.base.Optional;
   
   //TODO unit tests
   public final class AisShipStaticUtil {
   
       public static Optional<Integer> lengthMetres(Optional<Integer> a, Optional<Integer> b,
               Optional<Integer> c, Optional<Integer> d) {
          if (a.isPresent() && b.isPresent())
              return Optional.of(a.get() + b.get());
          else {
              if (!a.isPresent() && !c.isPresent() && b.isPresent() && d.isPresent())
                  return b;
              else
                  return Optional.absent();
          }
      }
  
      public static Optional<Integer> lengthMetres(AisShipStatic m) {
          return lengthMetres(m.getDimensionA(), m.getDimensionB(), m.getDimensionC(),
                  m.getDimensionD());
      }
  
      public static Optional<Integer> widthMetres(Optional<Integer> a, Optional<Integer> b,
              Optional<Integer> c, Optional<Integer> d) {
          if (c.isPresent() && d.isPresent())
              return Optional.of(c.get() + d.get());
          else {
              if (!a.isPresent() && !c.isPresent() && b.isPresent() && d.isPresent())
                  return d;
              else
                  return Optional.absent();
          }
      }
  
      public static Optional<Integer> widthMetres(AisShipStatic m) {
          return widthMetres(m.getDimensionA(), m.getDimensionB(), m.getDimensionC(),
                  m.getDimensionD());
      }
  }