//+------------------------------------------------------------------+
//|                                         Tick Volume Indicator v2 |
//|                                         Copyright © William Blau |
//|                           Originally coded © 2006 by Profitrader |
//|                                       Recoded © 2011 by MaryJane |
//+------------------------------------------------------------------+
#property copyright "Profitrader, 2006 && MaryJane, 2011"
//+------------------------------------------------------------------+
//---- properties
#property indicator_separate_window
#property indicator_buffers 5
#property indicator_color1 DodgerBlue     // for line graph, set color1-color4
#property indicator_color2 Red            // to CLR_NONE = set None in user
#property indicator_color3 DodgerBlue     // settings.
#property indicator_color4 Red            //
#property indicator_color5 Ivory          // set CLR_NONE to hide the line
#property indicator_width1 3
#property indicator_width2 3
#property indicator_width3 3
#property indicator_width4 3
#property indicator_width5 3
//+------------------------------------------------------------------+
//---- input parameters
extern int     r                 = 12;
extern int     s                 = 12;
extern int     u                 = 5;
extern string  _n1               = "_Increase for more history";
extern int     BarCount          = 500;
extern string  _n2               = "_AlertCandle = 0: current";
extern string  _n3               = "_AlertCandle = 1: closed";
extern int     AlertCandle       = 1;
extern bool    PopupAlerts       = false; 
extern string  _n4               = "_Leave empty for no email";
extern string  AlertEmailSubject = "";
//+------------------------------------------------------------------+
//---- globalscape
datetime       LastAlertTime     = -999999;
string         AlertUp          = "TVI change: UP";
string         AlertDn          = "TVI change: DOWN";
int            Precision         = 5;
datetime       OldTime;
string         ShortName;
//+------------------------------------------------------------------+
//---- buffers
double UpPos[], DnPos[], UpNeg[], DnNeg[];
double TVI[], TVI_Raw[], Trend[];
//+------------------------------------------------------------------+
//---- extra buffers
double UpTicks[], DnTicks[];
double EMA_U[], EMA_D[], DEMA_U[], DEMA_D[];
//+------------------------------------------------------------------+
//| indicator initialization                                         |
//+------------------------------------------------------------------+
int init()
   { 
   //---- data window / tooltip precision
   IndicatorDigits(Precision);
   //---- 7 buffers used (one still free)
   IndicatorBuffers(7);
   //---- 5 buffers for drawing
   SetIndexBuffer(0, UpPos);
   SetIndexBuffer(1, DnPos);
   SetIndexBuffer(2, UpNeg);
   SetIndexBuffer(3, DnNeg);
   SetIndexBuffer(4, TVI);
   SetIndexStyle(0, DRAW_HISTOGRAM); 
   SetIndexStyle(1, DRAW_HISTOGRAM);
   SetIndexStyle(2, DRAW_HISTOGRAM);
   SetIndexStyle(3, DRAW_HISTOGRAM);
   SetIndexStyle(4, DRAW_LINE);
   //---- 2 buffers for calculations
   SetIndexBuffer(5, TVI_Raw);
   SetIndexBuffer(6, Trend);
   //---- 6 additional buffers for calc
   ArrayResize(UpTicks, BarCount); ArraySetAsSeries(UpTicks, true);
   ArrayResize(DnTicks, BarCount); ArraySetAsSeries(DnTicks, true);
   ArrayResize(EMA_U, BarCount); ArraySetAsSeries(EMA_U, true);
   ArrayResize(EMA_D, BarCount); ArraySetAsSeries(EMA_D, true);
   ArrayResize(DEMA_U, BarCount); ArraySetAsSeries(DEMA_U, true);
   ArrayResize(DEMA_D, BarCount); ArraySetAsSeries(DEMA_D, true);
   // ---- disable data values for histo buffers
   SetIndexLabel(0, NULL); SetIndexLabel(1, NULL); SetIndexLabel(2, NULL); SetIndexLabel(3, NULL);
   // ---- enable data value for TVI
   SetIndexLabel(4, "TVI Value");
   //---- reset bar counter  
   OldTime = Time[0];
   //---- collect indi name
   ShortName = "TVI v2 (" + r + "," + s + "," + u + ") Trend is ";
   //---- end init
   return(0);
   }
//+------------------------------------------------------------------+
//| indicator code                                                   |
//+------------------------------------------------------------------+
int start()
   {
   int counted_bars = IndicatorCounted();
   if (counted_bars < 0) return (-1);
   if (counted_bars > 0) counted_bars--;
   int limit = MathMin(BarCount, Bars - counted_bars) - 1;
      
   //---- resize/shift extra buffers on first and every next bar
   if (Time[0] != OldTime) SyncExtraBuffers(BarCount);
   //---- calculate ticks
   for(int i = limit; i >= 0; i--)
      {
      UpTicks[i] = (Volume[i] + (Close[i] - Open[i]) / Point) / 2;
      DnTicks[i] = Volume[i] - UpTicks[i];
      }
   //---- 1st pass smoothing   
   for(i = limit; i >= 0; i--)
      {
      EMA_U[i] = iMAOnArray(UpTicks, 0, r, 0, MODE_EMA, i);
      EMA_D[i] = iMAOnArray(DnTicks, 0, r, 0, MODE_EMA, i);
      }
   //---- 2nd pass smoothing   
   for(i = limit; i >= 0; i--)
      {
      DEMA_U[i] = iMAOnArray(EMA_U, 0, s, 0, MODE_EMA, i);
      DEMA_D[i] = iMAOnArray(EMA_D, 0, s, 0, MODE_EMA, i);
      }
   //---- calculate the ratio   
   for(i = limit; i >= 0; i--)
      TVI_Raw[i] = 100.0 * (DEMA_U[i] - DEMA_D[i]) / (DEMA_U[i] + DEMA_D[i]);
   //---- final smoothing   
   for(i = limit; i >= 0; i--)
      TVI[i] = iMAOnArray(TVI_Raw, 0, u, 0, MODE_EMA, i);
   //---- make histogram
   for(i = limit; i >= 0; i--)
      {
      // ---- keep previous direction
      Trend[i] = Trend[i + 1];
      // ---- ...until there's a change
      if (TVI[i] > TVI[i + 1]) Trend[i] = 1;
      else if (TVI[i] < TVI[i + 1]) Trend[i] = -1;
      // ---- paint the buffers accordingly
      if (Trend[i] > 0)
         {
         if (TVI[i] >= 0) {UpPos[i] = TVI[i]; DnPos[i] = EMPTY_VALUE;}
         else {UpNeg[i] = TVI[i]; DnNeg[i] = EMPTY_VALUE;}
         }
      else if (Trend[i] < 0)
         {
         if (TVI[i] >= 0) {DnPos[i] = TVI[i]; UpPos[i] = EMPTY_VALUE;}
         else {DnNeg[i] = TVI[i]; UpNeg[i] = EMPTY_VALUE;}
         }
      }
   //---- trend display update
   if (Trend[0] == 1) string t = "UP"; else t = "DOWN";
   IndicatorShortName(ShortName + t);
   //---- do alerts
   ProcessAlerts();
   //---- end of loop
   return(0);
   }
//+------------------------------------------------------------------+
//| shift extra buffers on new bar                                   |
//+------------------------------------------------------------------+
void SyncExtraBuffers(int count)
   {
   for (int i = count - 1; i >= 0; i--)
      {
      UpTicks[i + 1] = UpTicks[i];
      DnTicks[i + 1] = DnTicks[i];
      EMA_U[i + 1] = EMA_U[i];
      EMA_D[i + 1] = EMA_D[i];
      DEMA_U[i + 1] = DEMA_U[i];
      DEMA_D[i + 1] = DEMA_D[i];
      }
   //---- reset bar counter   
   OldTime = Time[0];
   }
//+------------------------------------------------------------------+
//| alert routine (thank you hanover :-)                             |
//| http://www.forexfactory.com/showthread.php?t=299520              |
//+------------------------------------------------------------------+
void ProcessAlerts()
   {               
   if (AlertCandle >= 0  &&  Time[0] > LastAlertTime)
      {
      //---- alert UP
      if (Trend[AlertCandle] == 1 &&  Trend[AlertCandle + 1] != 1)
         {
         string AlertText = Symbol() + "," + TFToStr(Period()) + ": " + AlertUp;
         if (PopupAlerts) Alert(AlertText);
         if (AlertEmailSubject > "") SendMail(AlertEmailSubject, AlertText);
         LastAlertTime = Time[0]; 
         }
      //---- alert DOWN
      if (Trend[AlertCandle] == - 1  &&  Trend[AlertCandle + 1] != -1)
         {
         AlertText = Symbol() + "," + TFToStr(Period()) + ": " + AlertDn;
         if (PopupAlerts) Alert(AlertText);
         if (AlertEmailSubject > "") SendMail(AlertEmailSubject, AlertText);
         LastAlertTime = Time[0]; 
         }
      }
   }
//+------------------------------------------------------------------+
string TFToStr(int tf)
   {
   if (tf == 0)        tf = Period();
   if (tf >= 43200)    return("MN"); 
   if (tf >= 10080)    return("W1"); 
   if (tf >=  1440)    return("D1"); 
   if (tf >=   240)    return("H4"); 
   if (tf >=    60)    return("H1"); 
   if (tf >=    30)    return("M30");
   if (tf >=    15)    return("M15");
   if (tf >=     5)    return("M5"); 
   if (tf >=     1)    return("M1"); 
   return("");
   }