//+------------------------------------------------------------------+
//|                                                  Heiken Ashi.mq4 |
//|                      Copyright c 2004, MetaQuotes Software Corp. |
//|                                        http://www.metaquotes.net |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2004, MetaQuotes Software Corp."
#property link      "http://www.metaquotes.net"

#property indicator_chart_window
#property indicator_buffers 4
#property indicator_color1 Red
#property indicator_color2 Lime
#property indicator_color3 Blue
#property indicator_color4 Blue
#property indicator_width1 3
#property indicator_width2 3
#property indicator_width3 3
#property indicator_width4 3

extern int       TimeFrame=0;
extern int       EMA_Period=13;
extern int       MACD_FastPeriod=12;
extern int       MACD_SlowPeriod=26;
extern int       MACD_SignalPeriod=9;
extern bool      UseMT4MACD=false;

//---- buffers
double ExtMapBuffer1[];
double ExtMapBuffer2[];
double ExtMapBuffer3[];
double ExtMapBuffer4[];

double MACDLineBuffer[];
double MACDSignalLineBuffer[];
double MACDHistogramBuffer[];

//----
int ExtCountedBars=0;
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//|------------------------------------------------------------------|
int init()
  {
   IndicatorBuffers(7);

//---- indicators
   SetIndexStyle(0,DRAW_HISTOGRAM, 0, 3);
   SetIndexBuffer(0, ExtMapBuffer1);
   SetIndexStyle(1,DRAW_HISTOGRAM, 0, 3);
   SetIndexBuffer(1, ExtMapBuffer2);
   SetIndexStyle(2,DRAW_HISTOGRAM, 0, 3);
   SetIndexBuffer(2, ExtMapBuffer3);
   SetIndexStyle(3,DRAW_HISTOGRAM, 0, 3);
   SetIndexBuffer(3, ExtMapBuffer4);
//----
   SetIndexDrawBegin(0,MACD_SlowPeriod);
   SetIndexDrawBegin(1,MACD_SlowPeriod);
   SetIndexDrawBegin(2,MACD_SlowPeriod);
   SetIndexDrawBegin(3,MACD_SlowPeriod);
   
//---- indicator buffers mapping
   SetIndexBuffer(0,ExtMapBuffer1);
   SetIndexBuffer(1,ExtMapBuffer2);
   SetIndexBuffer(2,ExtMapBuffer3);
   SetIndexBuffer(3,ExtMapBuffer4);

   SetIndexEmptyValue(4,0.0);
   SetIndexBuffer(4,MACDSignalLineBuffer);
   SetIndexEmptyValue(5,0.0);
   SetIndexBuffer(5,MACDLineBuffer);
   SetIndexEmptyValue(6,0.0);
   SetIndexBuffer(6,MACDHistogramBuffer);
//---- initialization done

   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator deinitialization function                       |
//+------------------------------------------------------------------+
int deinit()
  {
//---- TODO: add your code here
   
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int start()
  {
   int    limit,y=0,counted_bars=IndicatorCounted();
   double ema1, main1, signal1, ema0, main0, signal0, macd1, macd0, main;
   double alpha = 2.0 / (MACD_SignalPeriod + 1.0);
   double alpha_1 = 1.0 - alpha;
   double BarValue, aOpen, aClose;   

   if(Bars<=10) return(0);
   ExtCountedBars=IndicatorCounted();
//---- check for possible errors
   if (ExtCountedBars<0) return(-1);
//---- last counted bar will be recounted
   if (ExtCountedBars>0) ExtCountedBars--;
   int pos=Bars-ExtCountedBars-1;
   while(pos>=0)
   {
      y = iBarShift(NULL,TimeFrame,Time[pos]); 
      ema0=iMA(NULL,TimeFrame,EMA_Period,0,MODE_EMA,PRICE_CLOSE,y); 
      ema1=iMA(NULL,TimeFrame,EMA_Period,0,MODE_EMA,PRICE_CLOSE,y+1); 

      if(UseMT4MACD)
      {
        main0=iMACD(NULL, TimeFrame, MACD_FastPeriod, MACD_SlowPeriod, MACD_SignalPeriod, PRICE_CLOSE,0,y); 
        main1=iMACD(NULL, TimeFrame, MACD_FastPeriod, MACD_SlowPeriod, MACD_SignalPeriod, PRICE_CLOSE,0,y+1); 

        signal0=iMACD(NULL, TimeFrame, MACD_FastPeriod, MACD_SlowPeriod, MACD_SignalPeriod, PRICE_CLOSE,1,y); 
        signal1=iMACD(NULL, TimeFrame, MACD_FastPeriod, MACD_SlowPeriod, MACD_SignalPeriod, PRICE_CLOSE,1,y+1); 
        
        main=main0; 
        macd0=main0-signal0;
        macd1=main1-signal1;
      } else
      {
        MACDLineBuffer[y] = iMA(NULL,TimeFrame,MACD_FastPeriod,0,MODE_EMA,PRICE_CLOSE,y)- 
                            iMA(NULL,TimeFrame,MACD_SlowPeriod,0,MODE_EMA,PRICE_CLOSE,y);
        MACDSignalLineBuffer[y]=(alpha*MACDLineBuffer[y]) + (alpha_1*MACDSignalLineBuffer[y+1]);
        MACDHistogramBuffer[y]=MACDLineBuffer[y]-MACDSignalLineBuffer[y];
        
        main=MACDLineBuffer[y]; 
        macd0=MACDHistogramBuffer[y];
        macd1=MACDHistogramBuffer[y+1];
      }
      aOpen=iOpen(NULL,TimeFrame,y);
      aClose=iClose(NULL,TimeFrame,y);
      if(ema0<ema1 && macd0<macd1) //both down - Red
      {
        if(aOpen<aClose)
        {
          ExtMapBuffer1[pos]=aClose;
          ExtMapBuffer2[pos]=aOpen;
          ExtMapBuffer3[pos]=EMPTY_VALUE;
          ExtMapBuffer4[pos]=EMPTY_VALUE;
        } else
        {
          ExtMapBuffer1[pos]=aOpen;
          ExtMapBuffer2[pos]=aClose;
          ExtMapBuffer3[pos]=EMPTY_VALUE;
          ExtMapBuffer4[pos]=EMPTY_VALUE;
        }
      } else
      if(ema0>ema1 && macd0>macd1) //both up - Lime
      {
        if(aOpen<aClose)
        {
          ExtMapBuffer1[pos]=aOpen;
          ExtMapBuffer2[pos]=aClose;
          ExtMapBuffer3[pos]=EMPTY_VALUE;
          ExtMapBuffer4[pos]=EMPTY_VALUE;
        } else
        {
          ExtMapBuffer1[pos]=aClose;
          ExtMapBuffer2[pos]=aOpen;
          ExtMapBuffer3[pos]=EMPTY_VALUE;
          ExtMapBuffer4[pos]=EMPTY_VALUE;
        }
      } else  //otherwise - Blue
      {
          ExtMapBuffer3[pos]=aOpen;
          ExtMapBuffer4[pos]=aClose;
          ExtMapBuffer1[pos]=EMPTY_VALUE;
          ExtMapBuffer2[pos]=EMPTY_VALUE;
      }
      pos--;
   }
//----
   return(0);
  }
//+------------------------------------------------------------------+