//+------------------------------------------------------------------+
//| trendsignal.mq4
//| contact pankajbhaban@gmail.Com
//+------------------------------------------------------------------+
#property indicator_chart_window
#property indicator_buffers 2
#property indicator_color1 DodgerBlue
#property indicator_color2 Magenta

//---- input parameters
extern int RISK=3;
extern int CountBars=350;
extern int Alert_Delay_In_Seconds=0;
extern bool Enablemail = true;
extern string subjectUp="Buy signal";
extern string subjectDown="Sell signal";
extern string textUp="Long ";
extern string textDown="Short ";
int SSP=9;
int PrevAlertTime=0;
//---- buffers
double val1[];
double val2[];
double alertBar;
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
//---- indicator line
   IndicatorBuffers(2);
   SetIndexStyle(0,DRAW_ARROW);
   SetIndexArrow(0,233);
   SetIndexStyle(1,DRAW_ARROW);
   SetIndexArrow(1,234);
   SetIndexBuffer(0,val1);
   SetIndexBuffer(1,val2);
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| SilverTrend_Signal                                               |
//+------------------------------------------------------------------+
int start()
  {
   if (Bars<CountBars) return(-1);
   //if(CountBars>=Bars) CountBars=Bars;
   SetIndexDrawBegin(0,Bars-CountBars+SSP);
   SetIndexDrawBegin(1,Bars-CountBars+SSP);
   int shift;
   int i1,i2,K;
   double Range,AvgRange,smin,smax,SsMax,SsMin,price;
   bool uptrend,old;
//----
   //if(Bars<=SSP+1) return(0);
//---- initial zero
   /*if(counted_bars<SSP+1)
     {
      for(i=1;i<=SSP;i++) val1[CountBars-i]=0.0;
      for(i=1;i<=SSP;i++) val2[CountBars-i]=0.0;
     }
     */
//----
   int counted_bars = IndicatorCounted();
   if(counted_bars < 0)  return(-1);
   if(counted_bars > 0)   counted_bars--;
   int limit = Bars - counted_bars;
   if(counted_bars==0) limit-=1+SSP;
   
   K=33-RISK;
   for(shift=limit; shift>=0; shift--)
     {
      Range=0;
      AvgRange=0;
      for(i1=shift; i1<=shift+SSP; i1++)
        {
         AvgRange=AvgRange+MathAbs(High[i1]-Low[i1]);
        }
      Range=AvgRange/(SSP+1);

      SsMax=High[shift]; SsMin=Low[shift];
      for(i2=shift;i2<=shift+SSP-1;i2++)
        {
         price=High[i2];
         if(SsMax<price) SsMax=price;
         price=Low[i2];
         if(SsMin>=price) SsMin=price;
        }

      smin = SsMin+(SsMax-SsMin)*K/100;
      smax = SsMax-(SsMax-SsMin)*K/100;
      val1[shift]=0;
      val2[shift]=0;
      if(Close[shift]<smin)
        {
         uptrend=false;
        }
      if(Close[shift]>smax)
        {
         uptrend=true;
        }
      if(uptrend!=old && uptrend==true)
        {
         val1[shift]=Low[shift]-Range*0.5;

         if(Bars>alertBar && shift==0 && (CurTime()-PrevAlertTime>Period()*Alert_Delay_In_Seconds))
           {
            Alert("Trendsignal ",Period()," ",Symbol()," BUY");alertBar=Bars;
            if(Enablemail==true) {SendMail(subjectDown+" "+Symbol(),textDown+" "+Close[1]+" "+Symbol()); }
            PrevAlertTime= CurTime();
           }
        }
      if(uptrend!=old && uptrend==false)
        {

         val2[shift]=High[shift]+Range*0.5;
         if(Bars>alertBar && shift==0 && (CurTime()-PrevAlertTime>Period()*Alert_Delay_In_Seconds))
           {
            Alert("Trendsignal ",Period()," ",Symbol()," SELL");alertBar=Bars;
            if(Enablemail==true) {SendMail(subjectUp+" "+Symbol(),textUp+" "+Close[1]+" "+Symbol());}
            PrevAlertTime= CurTime();
           }
        }
      Comment(shift);
      old=uptrend;

     }
   return(0);
  }
//+------------------------------------------------------------------+