//+---------------------------------+
//|        BREW_MissingData_Sep.mq4 |
//+---------------------------------+
#property  copyright "Copyright © 2010, Brewmanz"
#property link      "http://www.metaquotes.net/"

//#property indicator_chart_window
#property indicator_separate_window
#property indicator_buffers 1
#property  indicator_color1  Red
#property  indicator_width1 3
//---- input parameters
extern int AlertIfMissingPeriodsOver=10;
extern int AlertLimit=10;
//---- display buffers
double V1Buff[];
int AlertsToGo;
//+-------------------------------------------+
//| Custom indicator initialization function  |
//+-------------------------------------------+
int init()
{
   AlertsToGo = AlertLimit;
   //Print("Init() starting");
   string short_name;
   IndicatorBuffers(1);
//---- indicator line
   //SetIndexStyle( 0,DRAW_LINE);
   SetIndexStyle( 0,DRAW_HISTOGRAM);
   SetIndexBuffer(0,V1Buff);

//---- name for DataWindow and indicator subwindow label
   short_name="BREW MissingData(" + AlertIfMissingPeriodsOver + ")";
   IndicatorShortName(short_name);
   SetIndexLabel(0,"100+MissingIntervals");
//----
   SetIndexDrawBegin(0,1);
//----
   //Print("Init() ending");
   return(0);
  }
//+--------------------------------------+
int start()
{
   //Print("Start() top");
//----
   //if(Bars<=AtrPeriod) return(0);

   int ix, ixMax, ixP, counted_bars=IndicatorCounted();
   //Print("Bars=",Bars,",IndCnt=",IndicatorCounted());
   //---- check for possible errors
   if(counted_bars<0) return(-1);
   //---- the last counted bar will be recounted
   if(counted_bars>0) counted_bars--;
//---- count from oldest non-counted(treating most recent counted as to-be-recounted) to 0 (most recent)
   ixMax=Bars-counted_bars;
   for(ix = ixMax; ix >=0; ix--)
   {
      //if(ix > ixMax - TrailingBarsLength)//check if enough history to work
      //   continue;
      datetime dThis = Time[ix];
      datetime dPrev = Time[ix+1];
      int periodStep = (dThis - dPrev)/(Period()*60);
      // wait! if over weekend, deduct 'markets closed' time (49 hours)
      if(TimeDayOfWeek(dThis) < TimeDayOfWeek(dPrev))
         periodStep -= (49 * 60) / Period();
      int periodMissed = periodStep - 1;
      // is all okay?
      if(periodMissed <= 0)
      {
         V1Buff[ix] = 0;//EMPTY_VALUE;
         continue;
      }
      // oops. data is missing. could be weekend ...
      if(TimeDayOfWeek(dThis) < TimeDayOfWeek(dPrev))
      {
         if(periodMissed * Period() == 49 * 60)
         {
            V1Buff[ix] = 0;//EMPTY_VALUE;
            continue;
         }
      }

      Print(TimeToStr(dPrev), "-", TimeToStr(dThis), " Missing ", periodMissed, " Periods of ", Period(), " mins");
      if(periodMissed > AlertIfMissingPeriodsOver)
      {
         if(AlertsToGo > 0)
         {
            AlertsToGo--;
            Alert(TimeToStr(dPrev), "-", TimeToStr(dThis), " Missing ", periodMissed, " Periods of ", Period(), " mins");
         }
      }
      V1Buff[ix] = 100 + periodMissed;
   }
//---- plot any calced values

//----
   //Print("Start() ret");
   return(0);
  }
//+------------------------------------+