#ifndef __IntradayEma_h_
#define __IntradayEma_h_

#include "GenericTosData.h"
#include "StandardCandles.h"

// This always works off the close of each bar.  Like a normal chart on a
// desktop application, this include the bar in progress when computing the
// EMA.

class IntradayEma : public DataNode
{
private:
  StandardCandles *_candleData;
  GenericTosDataNode *_tosData;
  int _bars;
  double _portionOfNewValue;

  StandardCandles::Epoch _lastEpoch;
  int _currentBarCount;
  double _accumulator;  // This is the EMA at the end of the last bar.
  enum { wTos, wCandle };
  void onWakeup(int msgId);
  void onTos();
  void onCandle();
  void makeCurrent();
  void addValue(double value);
  double getValue(double last) const;

  IntradayEma(DataNodeArgument const &args);
  friend class DataNode;

public:
  // This was the state an instant before the last candle was complete, and the
  // current candle was created.
  bool getLastValid();
  double getLastValue();

  // This is the state including the candle currently in progress.
  bool getCurrentValid();
  double getCurrentValue();

  static DataNodeLink *find(DataNodeListener *listener, int msgId,
			    IntradayEma *&node,
			    std::string const &symbol, 
			    int minutesPerBar, int bars);
  static DataNodeLink *find(IntradayEma *&node,
                            std::string const &symbol,
                            int minutesPerBar, int bars);
};

#endif