//+------------------------------------------------------------------+
//|                                              Bollinger bands.mq4 |
//|                                 Copyright © 2008, Eugene Taranov |
//|                                         email: etaranov@live.com |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2008, Eugene Taranov, etaranov@live.com"
#property show_confirm
#define magic 578443
 
//+------------------------------------------------------------------+
//| Extern variables |
//+------------------------------------------------------------------+
  extern int bb_period = 150; //BollingerBands period
  extern int dev = 3; //BollingerBands deviatiion
  extern int h1 = 10; //set level 1
  extern int h2 = 50; //set level 2
  extern int h3 = 50; //set level 3
  extern double delta = 60; //level_h3 - bb_main
  extern double delta_h = 150; //level_h3 - bb_main high vol
  extern int time = 15;
//+------------------------------------------------------------------+
//| script program start function |
//+------------------------------------------------------------------+
 
int start()
  {
//------------------------------variables----------------------------+
  int orders = OrdersTotal (); //the number of orders
  int bb_shift = 0; //BollingerBands shift
  int app_price = 4; //BollingerBands applied price
  int type; //flag market/put off
  double price = Bid; //getting Bid
  double spread = Ask-Bid; //get spread
  int error; //Getlasterror variable
  bool setorder; //set new order
  int ticket; //order number
  double mlot; //market order size
  bool closedmarket; //market order is closed
//--------------------------------check------------------------------+
  if (orders > 1)
  {
  Alert("There are too many orders, ", orders);
  return;
  }
//------------------------------getordertype-------------------------+
  if (OrderSelect(0,SELECT_BY_POS)==true && OrderMagicNumber()==magic)
   {
    if (OrderType()==OP_BUY || OrderType()==OP_SELL)
     type = 1; //there is a market order
    else
     type = 0; //there is a put off order
   }  
//------------------------------getBBlines---------------------------+
  double bb_main = iBands(NULL,0,bb_period,dev,bb_shift,app_price,0,0);
  double bb_high = iBands(NULL,0,bb_period,dev,bb_shift,app_price,1,0);
  double bb_low = iBands(NULL,0,bb_period,dev,bb_shift,app_price,2,0);
  double level_h1 = (bb_high - bb_main)*0.01*h1+bb_main;
  double level_h2 = (bb_high - bb_main)*0.01*h2+bb_main;
  double level_h3 = (bb_high - bb_main)*0.01*h3+bb_main;
  double level_l1 = bb_main-((bb_main - bb_low)*0.01*h1);
  double level_l2 = bb_main-((bb_main - bb_low)*0.01*h2);
  double level_l3 = bb_main-((bb_main - bb_low)*0.01*h3);
//+----------------------------CloseOrder----------------------------+
     if (OrderSelect(0,SELECT_BY_POS)==true)
      {
        datetime timecur = TimeCurrent();
        datetime optime = OrderOpenTime();
        if (OrderType()==OP_BUY && OrderMagicNumber()==magic)
          {
           if ((timecur-optime)>time*3600)
           {
             ticket = OrderTicket();
             mlot = OrderLots();
             closedmarket = OrderClose(ticket,mlot,Bid,0);
             if (closedmarket == true)
               Alert("Buy order ",ticket," has been closed by the time");
             else
               Alert("Could not be closed: ",GetLastError());
            }
           }
        if (OrderType()==OP_SELL && OrderMagicNumber()==magic)
           {
             if ((timecur-optime)>time*3600)
             {
               ticket = OrderTicket();
               mlot = OrderLots();
               closedmarket = OrderClose(ticket,mlot,Ask,0);
               if (closedmarket == true)
                 Alert("Sell order ",ticket," has been closed by the time");
               else
                 Alert("Could not be closed: ",GetLastError());
             }       
           }
      }
//-----------------------------modifyorder---------------------------+
     if (type == 1 && ((Bid<level_h3 && Bid>=(level_h3-0.002)) || (Bid>level_l3 && Bid<=(level_l3+0.002))))
    {
      if (OrderSelect(0,SELECT_BY_POS)==true)
   {
        if (OrderType()==OP_BUY && OrderMagicNumber()==magic)                //modify buy order
           {
            ticket = OrderTicket();
            OrderModify(ticket,OrderOpenPrice(),level_l2,level_h3,0);
            Alert("Order ", ticket," has been modified");
           }
        else Alert(GetLastError());
        if (OrderType()==OP_SELL && OrderMagicNumber()==magic)               //modify sell order
           {
            ticket = OrderTicket();
            OrderModify(ticket,OrderOpenPrice(),level_h2+spread,level_l3+spread,0);
            Alert("Order ", ticket," has been modified");
           }
        else Alert(GetLastError());
         }
      else
         Alert ("Cannot select order to modify, error: ", GetLastError());
    }
   else
      Alert ("No need to modify");
//-------------------------------setorder----------------------------+
  RefreshRates();
  if (((level_h3-bb_main)>delta*Point)==true && (level_h3-bb_main)<delta_h*Point && type!=1)
   {
    if (price >(level_h1+spread) && iHigh(NULL,0,2) < level_h1 && iHigh(NULL,0,1)<level_h1)
      setorder = OrderSend (Symbol(),OP_BUY,0.01,price+spread,1,level_l2,level_h3,NULL,magic,0);
    if (setorder>0)
      Alert("Set buy order #",setorder);
    else
      Alert(GetLastError());
    if (price < level_l1 && iLow(NULL,0,2) > level_l1 && iLow(NULL,0,1) > level_l1)
      setorder = OrderSend (Symbol(),OP_SELL,0.01,price,1,level_h2,level_l3,NULL,magic,0);
    if (setorder>0)
      Alert("Set sell order #",setorder);
    else
      Alert(GetLastError());
   }
  else
   {
    Alert("Too calm market ",level_h3-bb_main);
    return;
   }
//-------------------------------------------------------------------+
  return(0);
  }
//+------------------------------------------------------------------+