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//+------------------------------------------------------------------+
//| PHONG.mq4 |
//| Copyright 2025, MetaQuotes Ltd. |
//| https://www.mql5.com |
//+------------------------------------------------------------------+
#property indicator_separate_window
#property indicator_buffers 1
#property indicator_color1 Blue // Lỗi: không nên khai báo lại
// Input variables
input int length = 3;
input double bull = -0.51;
input double bear = 0.43;
input int atr_length = 3;

// Indicator buffers
double cviBuffer[];

// Function to calculate SMA
double SMA(double &source[], int period, int shift = 0) {
double sum = 0;
for (int iSMA = shift; iSMA < period + shift; iSMA++) { // Thay `iLoop` thành `iSMA`
sum += source[iSMA];
}
return sum / period;
}

// Function to calculate ATR
double ATR(int period) {
double atr = 0;
for (int iATR = 1; iATR <= period; iATR++) { // Thay `iLoop` thành `iATR`
atr += MathAbs(High[iATR] - Low[iATR]);
}
return atr / period;
}

int OnInit() {
// Set buffer
SetIndexBuffer(0, cviBuffer);
SetIndexStyle(0, DRAW_LINE);
SetIndexLabel(0, "CVI");
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[]) {

// Ensure we have enough data
if (rates_total < length + atr_length) {
return (0);
}

// Compute hl2
double hl2[];
ArraySetAsSeries(hl2, true);
for (int iHL2 = 0; iHL2 < rates_total; iHL2++) { // Thay `iLoop` thành `iHL2`
hl2[iHL2] = (high[iHL2] + low[iHL2]) / 2;
}

// Compute ATR
double vol[];
ArraySetAsSeries(vol, true);
for (int iVol = 0; iVol < rates_total; iVol++) { // Thay `iLoop` thành `iVol`
vol[iVol] = ATR(atr_length);
}

// Compute CVI
for (int iCVI = rates_total - 1; iCVI >= 0; iCVI--) { // Thay `iLoop` thành `iCVI`
double valC = SMA(hl2, length, iCVI);
double atr_val = vol[iCVI] * MathSqrt(length);
cviBuffer[iCVI] = (close[iCVI] - valC) / atr_val;
}

// Plot signals
for (int iSignal = rates_total - 1; iSignal >= 0; iSignal--) { // Thay `iLoop` thành `iSignal`
if (cviBuffer[iSignal] <= bull) {
if (iSignal < rates_total - 1 && cviBuffer[iSignal + 1] > bull) {
ObjectCreate(0, "bullSignal" + IntegerToString(iSignal), OBJ_LABEL, 0, time[iSignal], low[iSignal] - 5 * Point);
ObjectSetInteger(0, "bullSignal" + IntegerToString(iSignal), OBJPROP_COLOR, clrLime);
// Push notification
SendNotification("Bullish signal at " + TimeToString(time[iSignal], TIME_DATE | TIME_MINUTES) + " on " + Symbol());
// Screen alert
Alert("Bullish signal at " + TimeToString(time[iSignal], TIME_DATE | TIME_MINUTES) + " on " + Symbol());
}
}if (cviBuffer[iSignal] >= bear) {
if (iSignal < rates_total - 1 && cviBuffer[iSignal + 1] < bear) {
ObjectCreate(0, "bearSignal" + IntegerToString(iSignal), OBJ_LABEL, 0, time[iSignal], high[iSignal] + 5 * Point);
ObjectSetInteger(0, "bearSignal" + IntegerToString(iSignal), OBJPROP_COLOR, clrRed);

// Push notification
SendNotification("Bearish signal at " + TimeToString(time[iSignal], TIME_DATE | TIME_MINUTES) + " on " + Symbol());
// Screen alert
Alert("Bearish signal at " + TimeToString(time[iSignal], TIME_DATE | TIME_MINUTES) + " on " + Symbol());
}
}
}

return (rates_total);
}