//+------------------------------------------------------------------+
//|                                                      Fractal.mq5 |
//|                                  Copyright 2025, MetaQuotes Ltd. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2025, MetaQuotes Ltd."
#property link      "https://www.mql5.com"
#property version   "1.00"
#property indicator_chart_window
#property copyright "2025"
#property version   "1.40"
#property indicator_chart_window
#property indicator_plots 2
#property indicator_buffers 2

//--- Swing High
#property indicator_label1  "SwingHigh"
#property indicator_type1   DRAW_ARROW
#property indicator_color1  clrCrimson
#property indicator_width1  1

//--- Swing Low
#property indicator_label2  "SwingLow"
#property indicator_type2   DRAW_ARROW
#property indicator_color2  clrMediumSeaGreen
#property indicator_width2  1

input int InpLeftRightBars  = 3;  // swing detection size
input int InpLeftRightBars0 = 1;  // between-point minimum swing size

input ushort code = 170;        // Arrow symbol

double SwingHighBuffer[];
double SwingLowBuffer[];

int lastHighIndex = -1;
int lastLowIndex  = -1;

datetime last_bar_time = 0;

//------------------------------------------------------------
inline bool IsSwingHigh_L(const double &high[], int i, int L)
{
   for(int j = 1; j <= L; j++)
      if(high[i] <= high[i - j] || high[i] <= high[i + j]) return false;
   return true;
}
//------------------------------------------------------------
inline bool IsSwingLow_L(const double &low[], int i, int L)
{
   for(int j = 1; j <= L; j++)
      if(low[i] >= low[i - j] || low[i] >= low[i + j]) return false;
   return true;
}
//------------------------------------------------------------
int OnInit()
{
   SetIndexBuffer(0, SwingHighBuffer, INDICATOR_DATA);
   SetIndexBuffer(1, SwingLowBuffer,  INDICATOR_DATA);

   ArrayInitialize(SwingHighBuffer, 0.0);
   ArrayInitialize(SwingLowBuffer,  0.0);
   
   PlotIndexSetInteger(0, PLOT_ARROW, code);
   PlotIndexSetInteger(1, PLOT_ARROW, code);
   
   return(INIT_SUCCEEDED);
}
//------------------------------------------------------------
int OnCalculate(const int rates_total,
                const int prev_calculated,
                const datetime &time[],
                const double &open[],
                const double &high[],
                const double &low[],
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
{
   if(rates_total < InpLeftRightBars*2 + 1)
      return 0;

   if(rates_total > 0 && time[rates_total - 1] == last_bar_time)
      return rates_total;

   ArrayInitialize(SwingHighBuffer, 0.0);
   ArrayInitialize(SwingLowBuffer,  0.0);

   lastHighIndex = -1;
   lastLowIndex  = -1;

   int start = InpLeftRightBars;
   int end   = rates_total - 1 - InpLeftRightBars;

   for(int i = start; i <= end; i++)
   {
      bool isHigh = IsSwingHigh_L(high, i, InpLeftRightBars);
      bool isLow  = IsSwingLow_L(low,  i, InpLeftRightBars);

      // --- Swing High ---
      if(isHigh)
      {
         SwingHighBuffer[i] = high[i];

         if(lastHighIndex != -1 && lastHighIndex > lastLowIndex)
         {
            int a = lastHighIndex;
            int b = i;
            if(a > b) { int tmp = a; a = b; b = tmp; }

            double minVal = DBL_MAX;
            int minIndex = -1;

            for(int k = a + 1; k < b; k++)
            {
               // only consider swing lows with L = InpLeftRightBars0
               if(IsSwingLow_L(low, k, InpLeftRightBars0))
               {
                  if(low[k] < minVal)
                  {
                     minVal = low[k];
                     minIndex = k;
                  }
               }
            }

            if(minIndex != -1)
               SwingLowBuffer[minIndex] = minVal; // draw in SwingLowBuffer
         }

         lastHighIndex = i;
      }

      // --- Swing Low ---
      if(isLow)
      {
         SwingLowBuffer[i] = low[i];

         if(lastLowIndex != -1 && lastLowIndex > lastHighIndex)
         {
            int a = lastLowIndex;
            int b = i;
            if(a > b) { int tmp = a; a = b; b = tmp; }

            double maxVal = -DBL_MAX;
            int maxIndex = -1;

            for(int k = a + 1; k < b; k++)
            {
               // only consider swing highs with L = InpLeftRightBars0
               if(IsSwingHigh_L(high, k, InpLeftRightBars0))
               {
                  if(high[k] > maxVal)
                  {
                     maxVal = high[k];
                     maxIndex = k;
                  }
               }
            }

            if(maxIndex != -1)
               SwingHighBuffer[maxIndex] = maxVal; // draw in SwingHighBuffer
         }

         lastLowIndex = i;
      }
   }

   last_bar_time = time[rates_total - 1];
   return rates_total;
}