extern MqlRates rates[];


class CFvg{
   private:
   //bool isFvgTapped;
   struct fvg{
      double upperBand;
      double lowerBand;
      double range;
      int flag;
      bool isFvgTapped;
   };
   //ICollection 
   
   fvg latestFvg;
   
   
   public:
   //getters
   //bool getLatestFvgFlag();
   double getLatestFvgLowerBand();
   double getLatestFvgUpperBand();
   double getLatestFvgRange();
   bool getIsLatestFvgFresh();
   int isFvg(int index=2); //return the flag of fvg formed or NULL
   bool update();
   bool isFvgTapped();
};

//bool CFvg::getLatestFvgFlag(void){
//   
//   return latestFvg.flag;
//}

double CFvg::getLatestFvgLowerBand(){
   return latestFvg.lowerBand;
}

double CFvg::getLatestFvgUpperBand(void){
   return latestFvg.upperBand;
}

double CFvg::getLatestFvgRange(){
   return latestFvg.range;
}

bool CFvg::getIsLatestFvgFresh(void){
   return latestFvg.isFvgTapped;
}

//int CFvg::isFvg(/*int &flag*/){
//   if(rates[1].high<rates[3].low){ //there's a gap in candle 2
//      //flag=-1; //bearish fvg found
//   return -1;
//   }
//   else if(rates[1].low>rates[3].high){ //tail not meeting head 
//      //flag=1; //bullish fvg found
//   return 1;
//   }
//
//return NULL;}

int CFvg::isFvg(int index=2){
   if(rates[index-1].high<rates[index+1].low){ //there's a gap in candle 2
      //flag=-1; //bearish fvg found
   return -1;
   }
   else if(rates[index-1].low>rates[index+1].high){ //tail not meeting head 
      //flag=1; //bullish fvg found
   return 1;
   }

return NULL;}

bool CFvg::update() {
   if(isFvgTapped()==true){
      latestFvg.isFvgTapped=true;
   }

   int flag = isFvg();
   if (flag == NULL) return false; // no FVG in current 3-candle window

   // ── Derive candidate FVG bands from the same candles isFvg() inspects ──
   // Bearish FVG: impulse drove price down; gap sits between
   //   lowerBand = rates[1].high  (top of right candle)
   //   upperBand = rates[3].low   (bottom of left candle)
   // Bullish FVG: impulse drove price up; gap sits between
   //   lowerBand = rates[3].high  (top of left candle)
   //   upperBand = rates[1].low   (bottom of right candle)
   double upper, lower;
   if (flag == -1) {          // bearish
      upper = rates[3].low;
      lower = rates[1].high;
   } else {                   // bullish
      upper = rates[1].low;
      lower = rates[3].high;
   }
   double newRange = upper - lower;
   if (newRange <= 0) return false; // degenerate gap — skip

   // ── Consecutive-FVG guard ────────────────────────────────────────────
   // If the candidate has the same direction as the stored latestFvg AND
   // their price bands overlap, this is the same gap that has simply
   // extended beyond the standard 3-candle window — not a new FVG.
   // Registering it again would double-count the same structural feature.
   if (latestFvg.flag == flag && latestFvg.range > 0) {
      if(isFvg(3)==true){
         if(flag==1){
            latestFvg.upperBand=upper;
            latestFvg.range=latestFvg.upperBand-latestFvg.lowerBand;
         }
         else{ //prev bearish fvg
            latestFvg.lowerBand=lower;
            latestFvg.range=latestFvg.upperBand-latestFvg.lowerBand;
         }
      }
      //if (bandsOverlap) return false; // same FVG extending — skip
   }

   // ── New distinct FVG — populate latestFvg ───────────────────────────
   latestFvg.flag        = flag;
   latestFvg.upperBand   = upper;
   latestFvg.lowerBand   = lower;
   latestFvg.range       = newRange;
   latestFvg.isFvgTapped = false; // fresh, untouched gap

   return true;
}

bool CFvg::isFvgTapped(void){
   bool isTapped=(rates[0].high>latestFvg.upperBand && rates[0].low<latestFvg.lowerBand) 
   || (rates[0].high>latestFvg.lowerBand && rates[0].low<latestFvg.upperBand);
   
   return isTapped;
}