//+------------------------------------------------------------------+
//| Forex Sessions and Day Range Indicator                           |
//+------------------------------------------------------------------+
#property copyright "Your Name"
#property link      "https://www.example.com"
#property version   "1.00"
#property indicator_chart_window

#include <Arrays\ArrayObj.mqh>

struct SessionInfo {
   string name;
   int startHour;    // Standard start hour (GMT)
   int startMinute;
   int endHour;      // Standard end hour (GMT)
   int endMinute;
   bool *isDST(datetime); // DST check function
   int dstAdjustment; // Hours to add during DST
};

SessionInfo sessions[] = {
   {"Sydney", 21, 0, 5, 0, IsSydneyDST, 1},
   {"Tokyo", 23, 0, 8, 0, IsTokyoDST, 0},
   {"London", 7, 0, 15, 0, IsLondonDST, 1},
   {"New York", 12, 0, 17, 0, IsNewYorkDST, 1}
};

bool sessionActive[];
double sessionHigh[];
double sessionLow[];
datetime sessionStartTime[];
datetime sessionEndTime[];

double dayHigh = 0;
double dayLow = 0;
datetime dayStartTime;

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int OnInit() {
   ArrayResize(sessionActive, ArraySize(sessions));
   ArrayResize(sessionHigh, ArraySize(sessions));
   ArrayResize(sessionLow, ArraySize(sessions));
   ArrayResize(sessionStartTime, ArraySize(sessions));
   ArrayResize(sessionEndTime, ArraySize(sessions));
   
   for(int i=0; i<ArraySize(sessions); i++) {
      sessionActive[i] = false;
      sessionHigh[i] = 0;
      sessionLow[i] = 0;
      sessionStartTime[i] = 0;
      sessionEndTime[i] = 0;
   }
   
   dayHigh = 0;
   dayLow = 0;
   dayStartTime = 0;
   
   return(INIT_SUCCEEDED);
}

//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
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 currentTime = TimeCurrent();
   
   // Check each session
   for(int i=0; i<ArraySize(sessions); i++) {
      SessionInfo session = sessions[i];
      bool dstActive = session.isDST(currentTime);
      int adjStartHour = session.startHour + (dstActive ? session.dstAdjustment : 0);
      int adjEndHour = session.endHour + (dstActive ? session.dstAdjustment : 0);
      
      datetime todayStart = StringToTime(TimeToString(currentTime, TIME_DATE) + " " + 
                                        IntegerToString(adjStartHour) + ":" + 
                                        IntegerToString(session.startMinute));
      datetime todayEnd = StringToTime(TimeToString(currentTime, TIME_DATE) + " " + 
                                       IntegerToString(adjEndHour) + ":" + 
                                       IntegerToString(session.endMinute));
      
      // Handle sessions spanning midnight
      if(adjEndHour < adjStartHour) {
         todayEnd += 24 * 3600;
      }
      
      if(currentTime >= todayStart && currentTime < todayEnd) {
         if(!sessionActive[i]) {
            sessionActive[i] = true;
            sessionStartTime[i] = todayStart;
            sessionEndTime[i] = todayEnd;
            sessionHigh[i] = Bid;
            sessionLow[i] = Ask;
         } else {
            if(Bid > sessionHigh[i]) sessionHigh[i] = Bid;
            if(Ask < sessionLow[i]) sessionLow[i] = Ask;
         }
      } else {
         sessionActive[i] = false;
      }
   }
   
   // Check day range
   bool dstActiveNY = IsNewYorkDST(currentTime);
   int dayStartHour = dstActiveNY ? 21 : 22;
   datetime todayDayStart = StringToTime(TimeToString(currentTime, TIME_DATE) + " " + 
                                        IntegerToString(dayStartHour) + ":00");
   
   if(currentTime < todayDayStart) {
      todayDayStart -= 24 * 3600;
   }
   
   if(dayStartTime != todayDayStart) {
      dayStartTime = todayDayStart;
      dayHigh = Bid;
      dayLow = Ask;
   } else {
      if(Bid > dayHigh) dayHigh = Bid;
      if(Ask < dayLow) dayLow = Ask;
   }
   
   // Display information on chart
   string comment = "Active Forex Sessions:\n";
   for(int i=0; i<ArraySize(sessions); i++) {
      if(sessionActive[i]) {
         comment += sessions[i].name + " Session\n" +
                    "High: " + DoubleToString(sessionHigh[i], _Digits) + "\n" +
                    "Low: " + DoubleToString(sessionLow[i], _Digits) + "\n";
      }
   }
   comment += "\nDay Range:\n" +
              "High: " + DoubleToString(dayHigh, _Digits) + "\n" +
              "Low: " + DoubleToString(dayLow, _Digits);
   Comment(comment);
   
   return(rates_total);
}

//+------------------------------------------------------------------+
//| DST Check Functions                                              |
//+------------------------------------------------------------------+
bool IsLondonDST(datetime time) {
   int year = TimeYear(time);
   datetime march31 = StringToTime(year + ".03.31 00:00");
   int lastSundayMarch = TimeDay(march31) - (TimeDayOfWeek(march31) % 7);
   datetime dstStart = StringToTime(year + ".03." + IntegerToString(lastSundayMarch) + " 01:00");
   
   datetime oct31 = StringToTime(year + ".10.31 00:00");
   int lastSundayOct = TimeDay(oct31) - (TimeDayOfWeek(oct31) % 7);
   datetime dstEnd = StringToTime(year + ".10." + IntegerToString(lastSundayOct) + " 01:00");
   
   return time >= dstStart && time < dstEnd;
}

bool IsNewYorkDST(datetime time) {
   int year = TimeYear(time);
   datetime march1 = StringToTime(year + ".03.01 00:00");
   int dayOfWeekMarch1 = TimeDayOfWeek(march1);
   int secondSundayMarch = 1 + (7 - dayOfWeekMarch1) % 7 + 7;
   datetime dstStart = StringToTime(year + ".03." + IntegerToString(secondSundayMarch) + " 07:00");
   
   datetime nov1 = StringToTime(year + ".11.01 00:00");
   int dayOfWeekNov1 = TimeDayOfWeek(nov1);
   int firstSundayNov = 1 + (7 - dayOfWeekNov1) % 7;
   datetime dstEnd = StringToTime(year + ".11." + IntegerToString(firstSundayNov) + " 06:00");
   
   return time >= dstStart && time < dstEnd;
}

bool IsSydneyDST(datetime time) {
   int year = TimeYear(time);
   datetime oct1 = StringToTime(year + ".10.01 00:00");
   int dayOfWeekOct1 = TimeDayOfWeek(oct1);
   int firstSundayOct = 1 + (7 - dayOfWeekOct1) % 7;
   datetime dstStart = StringToTime(year + ".10." + IntegerToString(firstSundayOct) + " 13:00");
   
   datetime apr1 = StringToTime(year + ".04.01 00:00");
   int dayOfWeekApr1 = TimeDayOfWeek(apr1);
   int firstSundayApr = 1 + (7 - dayOfWeekApr1) % 7;
   datetime dstEnd = StringToTime(year + ".04." + IntegerToString(firstSundayApr) + " 15:00");
   
   return time >= dstStart && time < dstEnd;
}

bool IsTokyoDST(datetime time) {
   return false;
}