using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace MarketData.MarketDataModel
{
  public class SignHolder
  {
    public enum SignValue { Positive, Negative, Undefined };
    private double currentValue;
    private double previousValue;

    public SignHolder()
    {
      currentValue = previousValue = 0.00;
    }
    public void SetValue(double value)
    {
      if (value == 0.00)
      {
        previousValue = currentValue;
        return;
      }
      previousValue = currentValue;
      currentValue = value;
    }
    public bool SignChange
    {
      get
      {
        if (previousValue < 0.00 && currentValue > 0.00) return true;
        if (previousValue > 0.00 && currentValue < 0.00) return true;
        return false;
      }
    }
    public double PreviousValue
    {
      get { return previousValue; }
    }
    public double CurrentValue
    {
      get { return currentValue; }
    }
    public String GetValueString()
    {
      StringBuilder sb = new StringBuilder();
      sb.Append("[").Append(previousValue).Append("->").Append(currentValue).Append("]");
      return sb.ToString();
    }
  }
}