//+------------------------------------------------------------------+
//|                                                      CandleLines.mq4|
//|                        Copyright 2024, YourNameHere                |
//|                                       http://www.yourwebsite.com   |
//+------------------------------------------------------------------+
#property strict
#property indicator_chart_window
#property indicator_buffers 4
#property indicator_color1 clrBlack
#property indicator_style1 STYLE_SOLID
#property indicator_width1 2
#property indicator_color2 clrGreen
#property indicator_style2 STYLE_SOLID
#property indicator_width2 2
#property indicator_color3 clrBlue
#property indicator_style3 STYLE_SOLID
#property indicator_color4 clrRed
#property indicator_style4 STYLE_SOLID

double OpenBuffer[];
double CloseBuffer[];
double COBuffer[];
double S1Buffer[];

int OnInit()
{
   // Set the indicator buffers
   SetIndexBuffer(0, OpenBuffer);
   SetIndexBuffer(1, CloseBuffer);
   SetIndexBuffer(2, COBuffer);
   SetIndexBuffer(3, SMA26Buffer);

   SetIndexLabel(0, "open");
   SetIndexLabel(1, "close");
   SetIndexLabel(2, "co");
   SetIndexLabel(3, "sma26");

   return(INIT_SUCCEEDED);
}

int OnCalculate(const int rates_total,
                const int prev_calculated,
                const datetime &time[],
                const double &open[],
                const double &high[],
                const double &low[],
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
{
   int barsToProcess = rates_total - prev_calculated;
   
   // Loop through the bars
   for(int i = 0; i < barsToProcess; i++)
   {
      int bufferIndex = rates_total - i - 1;

      datetime currentTime = time[bufferIndex];

      datetime m15Time = iTime(NULL, PERIOD_M15, iBarShift(NULL, PERIOD_M15, currentTime, true));
      int m15bar = iBarShift(NULL, PERIOD_M15, currentTime, true);

      double m15Open = iOpen(NULL, PERIOD_M15, iBarShift(NULL, PERIOD_M15, m15Time));
      double m15Close = iClose(NULL, PERIOD_M15, iBarShift(NULL, PERIOD_M15, m15Time));

      OpenBuffer[bufferIndex] = m15Open;
      CloseBuffer[bufferIndex] = m15Close;
      COBuffer[bufferIndex] = CloseBuffer[bufferIndex] - OpenBuffer[bufferIndex];
      
      // Calculate the SMA of the last 26 COBuffer values (except the live candle)
      double sum = 0;
      int count = 0;
      for(int j = bufferIndex + 1; j < rates_total && count < 26; j++, count++)
      {
         sum += COBuffer[j];
      }
      S1Buffer[bufferIndex] = (count > 0) ? sum / count : 0;
   }

   // Return that calculation is successful
   return(rates_total);
}