#property copyright "KK"
#property strict
#property indicator_chart_window
#property indicator_buffers 6 
#property indicator_color1  Yellow // SSL Felső/Alsó váltó (pirosas jelleg az eredetiben)
#property indicator_color2  Aqua   // SSL Alsó/Felső váltó (zöldes jelleg az eredetiben)
#property indicator_color3  White  // Középvonal (EMA)
#property indicator_style3  STYLE_DOT

//+------------------------------------------------------------------+
//| INPUTS                                                           | [cite: 20]
//+------------------------------------------------------------------+
extern int    Price         = PRICE_MEDIAN; 
extern double Deviations    = 1.0;         

extern string ___UI___      = "=== PERIOD BUTTON UI ===";
extern int    Button_X_Offset = 20;        // [cite: 22]
extern int    Button_Y_Offset = 40;        // [cite: 22]
extern int    Button_W        = 110;       // [cite: 23]
extern int    Button_H        = 25;        // [cite: 24]

//+------------------------------------------------------------------+
//| GLOBALS                                                          | [cite: 25]
//+------------------------------------------------------------------+
double buffer1[]; // Dinamikus SSL vonal 1
double buffer2[]; // Dinamikus SSL vonal 2
double buffer3[]; // Középvonal (EMA) [cite: 26]
double ema1[];    // Munka buffer az iEDev-hez
double ema2[];    // Munka buffer az iEDev-hez
double Hlv[];     // SSL trend állapot buffer [cite: 4, 5]

string ButtonName = "KK_EMA_Period_Btn";
string GVarName   = "KK_EMA_Period_";
int PeriodOptions[3] = {5, 20, 50};        // [cite: 27]
int LastPeriod        = -1;
bool ForceRecalc      = false;             // [cite: 28]

//+------------------------------------------------------------------+
//| HELPERS                                                          | [cite: 29]
//+------------------------------------------------------------------+
int GetCurrentPeriod()
{
   if(!GlobalVariableCheck(GVarName))
      GlobalVariableSet(GVarName, 5);
   int stored = (int)GlobalVariableGet(GVarName);
   for(int i = 0; i < 3; i++)              // [cite: 31]
      if(stored == PeriodOptions[i]) return stored;
   GlobalVariableSet(GVarName, 5);
   return 5;                               // [cite: 32]
}

int NextPeriod(int current)
{
   for(int i = 0; i < 3; i++)
      if(PeriodOptions[i] == current)
         return PeriodOptions[(i + 1) % 3];
   return 5;                               // [cite: 33]
}

//+------------------------------------------------------------------+
//| UI FUNKCIÓK                                                      | [cite: 34]
//+------------------------------------------------------------------+
void CreateButton()
{
   if(ObjectFind(ButtonName) < 0)
      ObjectCreate(ButtonName, OBJ_BUTTON, 0, 0, 0);
   ObjectSetInteger(0, ButtonName, OBJPROP_XDISTANCE,  Button_X_Offset); // [cite: 35]
   ObjectSetInteger(0, ButtonName, OBJPROP_YDISTANCE,  Button_Y_Offset);
   ObjectSetInteger(0, ButtonName, OBJPROP_XSIZE,      Button_W);
   ObjectSetInteger(0, ButtonName, OBJPROP_YSIZE,      Button_H);        // [cite: 36]
   ObjectSetInteger(0, ButtonName, OBJPROP_CORNER,     CORNER_LEFT_LOWER);
   ObjectSetInteger(0, ButtonName, OBJPROP_FONTSIZE,   9);               // [cite: 37]
   ObjectSetInteger(0, ButtonName, OBJPROP_SELECTABLE, false);
   ObjectSetInteger(0, ButtonName, OBJPROP_STATE,      false);

   UpdateButtonUI();
}

void UpdateButtonUI()
{
   int p = GetCurrentPeriod();
   color bg;
   if(p == 5)       bg = clrDodgerBlue;    // [cite: 39]
   else if(p == 20) bg = clrDarkOrange;
   else             bg = clrMediumSeaGreen; // [cite: 40]
   ObjectSetString(0,  ButtonName, OBJPROP_TEXT,   "Period: " + IntegerToString(p)); // [cite: 41]
   ObjectSetInteger(0, ButtonName, OBJPROP_BGCOLOR, bg);
   ObjectSetInteger(0, ButtonName, OBJPROP_COLOR,   clrWhite);
   ChartRedraw();                          // [cite: 42]
}

void OnChartEvent(const int id, const long &lparam, const double &dparam, const string &sparam)
{
   if(id == CHARTEVENT_OBJECT_CLICK && sparam == ButtonName)
   {
      int current = GetCurrentPeriod();
      int next    = NextPeriod(current);   // [cite: 43]
      GlobalVariableSet(GVarName, next);

      UpdateButtonUI();
      ObjectSetInteger(0, ButtonName, OBJPROP_STATE, false);

      ForceRecalc = true;
      LastPeriod  = -1;                    // [cite: 44]

      IndicatorShortName("EMA SSL Dev [P=" + IntegerToString(next) + "]");
      start();                             // [cite: 45]
   }
}

//+------------------------------------------------------------------+
//| init                                                             | [cite: 46]
//+------------------------------------------------------------------+
int init()
{
   IndicatorBuffers(6);
   SetIndexBuffer(0, buffer1); SetIndexStyle(0, DRAW_LINE);
   SetIndexBuffer(1, buffer2); SetIndexStyle(1, DRAW_LINE);
   SetIndexBuffer(2, buffer3); SetIndexStyle(2, DRAW_LINE);
   SetIndexBuffer(3, ema1);    SetIndexStyle(3, DRAW_NONE);
   SetIndexBuffer(4, ema2);    SetIndexStyle(4, DRAW_NONE);
   SetIndexBuffer(5, Hlv);     SetIndexStyle(5, DRAW_NONE); // SSL állapot buffer [cite: 6]

   GVarName += Symbol();

   if(!GlobalVariableCheck(GVarName))
      GlobalVariableSet(GVarName, 5);

   int p = GetCurrentPeriod();
   IndicatorShortName("EMA SSL Dev [P=" + IntegerToString(p) + "]"); // [cite: 48]
   CreateButton();                         // [cite: 49]
   return(0);
}

int deinit() { ObjectDelete(ButtonName); return(0); } // [cite: 50]

//+------------------------------------------------------------------+
//| start                                                            | [cite: 51]
//+------------------------------------------------------------------+
int start()
{
   int Periods = GetCurrentPeriod();

   if(Periods != LastPeriod || ForceRecalc)
   {
      LastPeriod  = Periods;
      ForceRecalc = false;                 // [cite: 52]
      ArrayInitialize(buffer1, EMPTY_VALUE);
      ArrayInitialize(buffer2, EMPTY_VALUE);
      ArrayInitialize(buffer3, EMPTY_VALUE);
      ArrayInitialize(ema1,    0);
      ArrayInitialize(ema2,    0);
      ArrayInitialize(Hlv,     0);         // [cite: 53]
   }

   int counted_bars = IndicatorCounted();
   if(counted_bars < 0) return(-1);
   
   bool needFullCalc = (ema1[Bars - 1] == 0 && Bars > 1); // [cite: 54]

   int limit;
   if(needFullCalc || counted_bars == 0) limit = Bars - 2; // [cite: 55]
   else limit = Bars - counted_bars;       // [cite: 56]
   
   if(limit >= Bars) limit = Bars - 2;

   double alpha = 2.0 / (1.0 + (double)Periods); // [cite: 57]

   for(int i = limit; i >= 0; i--)         // [cite: 58]
   {
      double price = iMA(NULL, 0, 1, 0, MODE_SMA, Price, i); // Ártípus kezelése [cite: 7]
      
      // EMA és Deviáció számítás (v2 stílusú optimalizált iEDev)
      ema1[i] = ema1[i+1] + alpha * (price - ema1[i+1]); // [cite: 61]
      ema2[i] = ema2[i+1] + alpha * (price * price - ema2[i+1]); // [cite: 62]
      buffer3[i] = ema1[i]; // Középvonal az EMA [cite: 7]

      double var = (double)Periods * (ema2[i] - ema1[i] * ema1[i]) / ((double)Periods - 1.0); // [cite: 63]
      double dev = (var > 0.0) ? MathSqrt(var) : 0.0; // [cite: 64]

      double upperBand = buffer3[i] + Deviations * dev; // [cite: 8]
      double lowerBand = buffer3[i] - Deviations * dev; // [cite: 8]

      // --- SSL LOGIKA (v1-ből átemelve) --- [cite: 9]
      Hlv[i] = Hlv[i+1];
      if(Close[i] > upperBand) Hlv[i] =  1; // [cite: 10]
      if(Close[i] < lowerBand) Hlv[i] = -1; // [cite: 10]

      if(Hlv[i] == -1) // Medve trend [cite: 11]
      {
         buffer1[i] = upperBand; // Sárga = Felső [cite: 12]
         buffer2[i] = lowerBand; // Aqua  = Alsó [cite: 13]
      }
      else // Bika trend
      {
         buffer1[i] = lowerBand; // Sárga = Alsó [cite: 14]
         buffer2[i] = upperBand; // Aqua  = Felső [cite: 15]
      }
   }

   return(0);
}