QQE_Cross Alert

//+------------------------------------------------------------------+
//|                                                    QQE_Cross.mq4 |
//+------------------------------------------------------------------+

#property indicator_chart_window
#property indicator_buffers 2
#property indicator_color1 Blue
#property indicator_color2 Red


extern int SF = 1;
extern bool Visual_Alert=true;
extern bool Audio_Alert=true;
extern string Audio_Up_File="alert.wav";
extern string Audio_Down_File="alert.wav";
extern bool Email_Alert=true;

extern int Count_Bars=EMPTY_VALUE;
extern int Arrow_Offset=5;

double ExtMapBuffer1[];
double ExtMapBuffer2[];

bool up=false;
bool dn=false;
datetime last_t=0;
int init()
  {
   SetIndexStyle(0,DRAW_ARROW);
   SetIndexArrow(0,233);
   SetIndexBuffer(0,ExtMapBuffer1);
   SetIndexEmptyValue(0,0.0);
   SetIndexStyle(1,DRAW_ARROW);
   SetIndexArrow(1,234);
   SetIndexBuffer(1,ExtMapBuffer2);
   SetIndexEmptyValue(1,0.0);
   return(0);
  }
int deinit(){return(0);}
int start()
  {
   int l=0;
   if (Count_Bars>Bars) {l=Bars;}else{l=Count_Bars;}
   for (int i=l;i>=0;i--){      
      ExtMapBuffer1[i]=0;
      ExtMapBuffer2[i]=0;
      double qqe0_0=iCustom(Symbol(),0,"QQE",SF,0,i);
      double qqe0_1=iCustom(Symbol(),0,"QQE",SF,0,i+1);
      double qqe1_0=iCustom(Symbol(),0,"QQE",SF,1,i);
      double qqe1_1=iCustom(Symbol(),0,"QQE",SF,1,i+1);
      
      if (qqe0_0>qqe1_0 && qqe0_1<=qqe1_1 && !up){
         ExtMapBuffer1[i]=Low[i]-Arrow_Offset*Point;
         up=true;
         dn=false;
      }
      if (qqe0_0<qqe1_0 && qqe0_1>=qqe1_1 && !dn){
         ExtMapBuffer2[i]=High[i]+Arrow_Offset*Point;
         dn=true;
         up=false;
      }
   }
   
   if (ExtMapBuffer1[0]>0){
      if (Visual_Alert) Alert("Cross up on : "+Symbol()+" at "+TimeToStr(TimeCurrent()));      
      if (Audio_Alert) PlaySound(Audio_Up_File);
      if (Email_Alert) SendMail("QQE_Cross Alert","Cross up on : "+Symbol()+" at "+TimeToStr(TimeCurrent()));
   }
   if (ExtMapBuffer2[0]>0){
      if (Visual_Alert) Alert("Cross down on : "+Symbol()+" at "+TimeToStr(TimeCurrent()));      
      if (Audio_Alert) PlaySound(Audio_Down_File);
      if (Email_Alert) SendMail("QQE_Cross Alert","Cross down on : "+Symbol()+" at "+TimeToStr(TimeCurrent()));
   }
   
   return(0);
  }