Port an indicator from TeleTrader to MT5

Hi,

This indicator is for TeleTrader and it needs to be ported to MT5.

Function supertrend
Returns Nothing;

Parameters
 Security Source;
 Numeric Factor;
 Numeric Period;

Variables
 Numeric volaValue;
 Numeric avgValue;
 Numeric upperValue;
 Numeric lowerValue;
 Numeric trendFlag(1);
 Numeric flagValue1;
 Numeric flagValue2;
 Numeric valOut;

Begin
 volaValue = #atr(Source, Period);
 avgValue = (Source.High + Source.Low) / 2;

 upperValue = avgValue + (Factor * volaValue);
 lowerValue = avgValue - (Factor * volaValue);

 If Source.Close > upperValue[1] Then
  trendFlag = 1
 Else If Source.Close < lowerValue[1] Then
  trendFlag = -1
 Else
  trendFlag = trendFlag[1];

 If trendFlag < 0 And trendFlag[1] > 0 Then
  flagValue1 = 1
 Else
  flagValue1 = 0;

 If trendFlag > 0 And trendFlag[1] < 0 Then
  flagValue2 = 1
 Else
  flagValue2 = 0;

 If trendFlag > 0 And lowerValue < lowerValue[1] Then
  lowerValue = lowerValue[1];

 If trendFlag < 0 And upperValue > upperValue[1] Then
  upperValue = upperValue[1];

 If flagValue1 = 1 Then
  upperValue = avgValue + (Factor * volaValue);

 If flagValue2 = 1 Then
  lowerValue = avgValue - (Factor * volaValue);

 If trendFlag = 1 Then
  valOut = lowerValue
 Else
  valOut = upperValue;

 DrawLine("SuperTrend", valOut);