150bool IsWeekday(const int weekday) { return weekday>=1 && weekday<=5; }151152// Rates are captured at initialization so sizing uses a stable conversion basis.153double FindPairBid(const string requested)154{155   double bid=SymbolInfoDouble(requested,SYMBOL_BID);156   if(bid>0.0) return bid;157   for(int scope=0;scope<2;scope++)158   {159      const bool selected=(scope==0);160      const int count=SymbolsTotal(selected);161      for(int i=0;i<count;i++)162      {163         string symbol=SymbolName(i,selected);164         if(StringSubstr(symbol,0,StringLen(requested))!=requested) continue;165         if(!selected) SymbolSelect(symbol,true);166         bid=SymbolInfoDouble(symbol,SYMBOL_BID);167         if(bid>0.0) return bid;168      }169   }170   return 0.0;171}172void BuildCurrencyRates()173{174   ratesReady=false;175   for(int i=0;i<ArraySize(currencies);i++)176   {177      const string currency=currencies[i];178      if(currency=="USD") { usdRates[i]=1.0; continue; }179      double rate=FindPairBid(currency+"USD");180      if(rate<=0.0)181      {182         double inverse=FindPairBid("USD"+currency);183         if(inverse>0.0) rate=1.0/inverse;184         else185         {186            double cross=FindPairBid("EUR"+currency);187            double eurUsd=FindPairBid("EURUSD");188            if(cross>0.0 && eurUsd>0.0) rate=eurUsd/cross;189         }190      }191      if(rate<=0.0)192      {193         Print("BuildRateCache WARNING: no rate for ",currency," - using 1.0 fallback");194         rate=1.0;195      }196      usdRates[i]=rate;197   }198   ratesReady=true;199   Print("Rate cache built: EUR=",usdRates[1]," GBP=",usdRates[2]," JPY=",usdRates[3]," CHF=",usdRates[4]);