python-mt5-support-resistance-indicator/MQL5/Indicators/SR_Research_Zones.mq5

// Educational companion: confirmed swing zones, not the Jericho Gold engine.
#property copyright "Support and Resistance Research"
#property version "1.00"
#property description "Confirmed swing zones for the Python and MT5 research article"
#property indicator_chart_window
#property indicator_plots 0
#property indicator_buffers 0

input int InpHistoryBars=2000;             // Recent chart bars to examine
input int InpSwingBars=2;                  // Closed candles on EACH side of a pivot
input int InpATRPeriod=14;                 // Simple mean true range, not Wilder smoothing
input double InpATRHalfWidth=0.25;         // Zone half-width / confirmation ATR
input double InpMinimumHalfWidthPoints=10; // Minimum half-width in broker points
input int InpMaximumZones=20;              // Latest zones in total
input bool InpShowSupport=true;
input bool InpShowResistance=true;
input bool InpInvalidateOnBreak=true;
input int InpBreakCloses=2;                // Consecutive closes beyond the whole zone
input bool InpShowBrokenZones=false;
input int InpExtendBars=200;               // Active rectangles extend past current bar
input bool InpFillZones=true;
input color InpSupportColor=C'190,222,208';
input color InpResistanceColor=C'237,200,200';

struct SRZone
{
   datetime pivot,available,ended;
   double lower,upper;
   int side; // 1 support, -1 resistance
   bool broken;
};
string srPrefix="";
datetime srLastBar=0;
int srLastCount=0;

// SR_CORE_BEGIN -- same function bodies are exercised by portable checks.
bool SRPivot(const MqlRates &r[],const int i,const int wing,const int side)
{
   for(int k=1;k<=wing;k++)
   {
      if(side>0 && (r[i].low>=r[i-k].low || r[i].low>=r[i+k].low)) return false;
      if(side<0 && (r[i].high<=r[i-k].high || r[i].high<=r[i+k].high)) return false;
   }
   return true; // Strict extremes: equal highs/lows do not qualify.
}
double SRHalfWidth(const MqlRates &r[],const int confirmed,const int period,
                  const double multiplier,const double minimum)
{
   double total=0;
   for(int j=confirmed-period+1;j<=confirmed;j++)
      total+=MathMax(r[j].high-r[j].low,
         MathMax(MathAbs(r[j].high-r[j-1].close),MathAbs(r[j].low-r[j-1].close)));
   return MathMax(minimum,multiplier*total/period);
}
int SRBreakIndex(const MqlRates &r[],const int first,const int last,const int side,
                 const double lower,const double upper,const int needed)
{
   int run=0;
   for(int j=first;j<=last;j++)
   {
      bool outside=(side>0)?r[j].close<lower:r[j].close>upper;
      run=outside?run+1:0;
      if(run>=needed) return j;
   }
   return -1;
}
// SR_CORE_END

void SRClear() { if(srPrefix!="") ObjectsDeleteAll(0,srPrefix,0,-1); }

bool SRDraw(const SRZone &z,const int serial,const datetime future)
{
   string name=srPrefix+IntegerToString(serial);
   datetime end=z.broken?z.ended:future;
   if(!ObjectCreate(0,name,OBJ_RECTANGLE,0,z.available,z.lower,end,z.upper))
   { Print("SR zones: drawing request failed, error ",GetLastError()); return false; }
   color ink=z.side>0?InpSupportColor:InpResistanceColor;
   bool ok=true;
   ok=ObjectSetInteger(0,name,OBJPROP_COLOR,ink)&&ok;
   ok=ObjectSetInteger(0,name,OBJPROP_FILL,InpFillZones)&&ok;
   ok=ObjectSetInteger(0,name,OBJPROP_BACK,true)&&ok;
   ok=ObjectSetInteger(0,name,OBJPROP_SELECTABLE,false)&&ok;
   ok=ObjectSetInteger(0,name,OBJPROP_HIDDEN,true)&&ok;
   ok=ObjectSetInteger(0,name,OBJPROP_WIDTH,1)&&ok;
   ok=ObjectSetInteger(0,name,OBJPROP_STYLE,z.broken?STYLE_DOT:STYLE_SOLID)&&ok;
   string note=(z.side>0?"Support":"Resistance");
   note+=(z.broken?" (broken)":" (active)");
   note+=
      "\nPivot: "+TimeToString(z.pivot)+"\nAvailable: "+TimeToString(z.available)+
      "\nBounds: "+DoubleToString(z.lower,_Digits)+" / "+DoubleToString(z.upper,_Digits);
   ok=ObjectSetString(0,name,OBJPROP_TOOLTIP,note)&&ok;
   return ok;
}

int OnInit()
{
   if(InpHistoryBars<100 || InpHistoryBars>10000 || InpSwingBars<1 || InpSwingBars>20 ||
      InpATRPeriod<1 || InpATRPeriod>200 || InpMaximumZones<1 || InpMaximumZones>100 ||
      InpBreakCloses<1 || InpBreakCloses>20 || InpExtendBars<1 || InpExtendBars>10000 ||
      !MathIsValidNumber(InpATRHalfWidth) || InpATRHalfWidth<=0 ||
      !MathIsValidNumber(InpMinimumHalfWidthPoints) || InpMinimumHalfWidthPoints<=0 ||
      InpHistoryBars<MathMax(2*InpSwingBars,InpATRPeriod)+2)
      return INIT_PARAMETERS_INCORRECT;
   srPrefix="SRR_"+(string)GetMicrosecondCount()+"_";
   srLastBar=0; srLastCount=0;
   IndicatorSetString(INDICATOR_SHORTNAME,"SR Research Zones");
   return INIT_SUCCEEDED;
}
void OnDeinit(const int reason) { SRClear(); ChartRedraw(0); }

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[])
{
   datetime current=iTime(_Symbol,_Period,0);
   if(current<=0) return prev_calculated;
   if(prev_calculated>0 && current==srLastBar && rates_total==srLastCount) return rates_total;
   int wanted=MathMin(rates_total,InpHistoryBars);
   MqlRates r[]; ArraySetAsSeries(r,false);
   int count=CopyRates(_Symbol,_Period,0,wanted,r);
   if(count<MathMax(2*InpSwingBars,InpATRPeriod)+2) return prev_calculated;
   if(r[count-1].time!=current) return prev_calculated;
   SRZone zones[];
   int lastClosed=count-2; // Excludes the forming candle from every calculation.
   int first=MathMax(InpSwingBars,InpATRPeriod-InpSwingBars);
   for(int i=first;i+InpSwingBars<=lastClosed;i++)
   {
      int confirmed=i+InpSwingBars;
      for(int side=1;side>=-1;side-=2)
      {
         if((side>0&&!InpShowSupport)||(side<0&&!InpShowResistance)) continue;
         if(!SRPivot(r,i,InpSwingBars,side)) continue;
         SRZone z;
         z.side=side; z.pivot=r[i].time; z.available=r[confirmed+1].time;
         double anchor=side>0?r[i].low:r[i].high;
         double width=SRHalfWidth(r,confirmed,InpATRPeriod,InpATRHalfWidth,InpMinimumHalfWidthPoints*_Point);
         z.lower=anchor-width; z.upper=anchor+width;
         int broken=InpInvalidateOnBreak?SRBreakIndex(r,confirmed+1,lastClosed,side,z.lower,z.upper,InpBreakCloses):-1;
         z.broken=broken>=0; z.ended=z.broken?r[broken+1].time:0;
         if(z.broken&&!InpShowBrokenZones) continue;
         int n=ArraySize(zones); ArrayResize(zones,n+1); zones[n]=z;
      }
   }
   SRClear();
   datetime future=current+(datetime)((long)PeriodSeconds(_Period)*InpExtendBars);
   int firstDraw=MathMax(0,ArraySize(zones)-InpMaximumZones);
   bool drawn=true;
   for(int i=firstDraw;i<ArraySize(zones);i++) drawn=SRDraw(zones[i],i,future)&&drawn;
   if(drawn) { srLastBar=current; srLastCount=rates_total; }
   ChartRedraw(0);
   return drawn?rates_total:0; // Retry failed requests on a later tick.
}