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//║ ██████╗██╗  ██╗ █████╗ ██████╗ ██████╗ █████╗  █████╗ █████╗ ███╗  ██╗ ║
//║ ██╔═══╝╚██╗██╔╝██╔══██╗██╔══██╗██╔═══╝██╔══██╗██╔═══╝██╔══██╗████╗ ██║ ║
//║ █████╗  ╚███╔╝ ██║  ██║██████╔╝█████╗ ███████║██║    ██║  ██║██╔██╗██║ ║
//║ ██╔══╝  ██╔██╗ ██║  ██║██╔══██╗██╔══╝ ██╔══██║██║    ██║  ██║██║╚████║ ║
//║ ██████╗██╔╝ ██╗╚█████╔╝██████╔╝██████╗██║  ██║╚█████╗╚█████╔╝██║ ╚███║ ║
//║ ╚═════╝╚═╝  ╚═╝ ╚════╝ ╚═════╝ ╚═════╝╚═╝  ╚═╝ ╚════╝ ╚════╝ ╚═╝  ╚══╝ ║
//╚═══════ Algorithms that observe ════ Signals that speak ════════════════╝

//+------------------------------------------------------------------+
//| Archivo: Donchian_Channels_Trend.mq5                             |
//| Origen: Replicación del "Donchian Channels Trend" de TradingView |
//| Autor Original: holdon_to_profits                                |
//| Descripción: Indicador de canales con memoria de estado (FSM).   |
//|              Detecta la tendencia basándose en rupturas de la    |
//|              estructura previa y cambia de color dinámicamente.  |
//+------------------------------------------------------------------+

#property copyright   "Exobeacon Labs"
#property link        "https://www.exobeacon.com/"
#property version     "1.0"
#property description "Donchian Channels Trend (holdon_to_profits) v1.0"
#property description "Trend-following breakout indicator."
#property description "Dynamic coloring based on trend state memory."
#property description "Identifies directional bias and structural levels."
#property description " "
#property description "〰〰〰〰〰((👽))〰〰〰〰〰"
#property description "🛸 mql5.com/en/users/ulisescalb"
#property description "🛸 github.com/Exobeacon-Labs"
#property strict

#property indicator_chart_window
#property indicator_buffers 7
#property indicator_plots   3

// --- Configuración Plot 1: Upper Band ---
#property indicator_label1  "Upper Band"
#property indicator_type1   DRAW_COLOR_LINE
#property indicator_color1  clrLime, clrRed
#property indicator_style1  STYLE_SOLID
#property indicator_width1  2

// --- Configuración Plot 2: Lower Band ---
#property indicator_label2  "Lower Band"
#property indicator_type2   DRAW_COLOR_LINE
#property indicator_color2  clrLime, clrRed
#property indicator_style2  STYLE_SOLID
#property indicator_width2  2

// --- Configuración Plot 3: Basis Line ---
#property indicator_label3  "Basis Line"
#property indicator_type3   DRAW_COLOR_LINE
#property indicator_color3  clrLime, clrRed
#property indicator_style3  STYLE_DASHDOT
#property indicator_width3  1

//+------------------------------------------------------------------+
//| ENTRADAS DEL USUARIO (Inputs)                                    |
//+------------------------------------------------------------------+
input group "====== Donchian Settings ======"
input int InpLength = 20; // Lookback Period (Length)

input group "====== Alert Settings ======"
input bool InpEnableAlerts = false; // Enable All Alerts
input bool InpAlertPopup   = true;  // Popup Alerts
input bool InpAlertSound   = true;  // Sound Alerts
input bool InpAlertPush    = false; // Push Notifications
input bool InpAlertEmail   = false; // Email Alerts

//+------------------------------------------------------------------+
//| BÚFERES GLOBALES (Buffers)                                       |
//+------------------------------------------------------------------+
double BufferUpper[];
double BufferUpperColor[];
double BufferLower[];
double BufferLowerColor[];
double BufferBasis[];
double BufferBasisColor[];
double BufferTrend[]; // Búfer oculto para memoria de tendencia (1 = Bullish, -1 = Bearish)

//+------------------------------------------------------------------+
//| VARIABLES GLOBALES AUXILIARES                                    |
//+------------------------------------------------------------------+
datetime g_lastAlertTime = 0; // Control de tiempo para evitar spam de alertas

//+------------------------------------------------------------------+
//| INIT FUNCTION                                                    |
//+------------------------------------------------------------------+
int OnInit()
{
    // 1. Validación estricta de parámetros
    if(InpLength < 1)
    {
        Print("Error: Lookback Period must be greater than 0.");
        return INIT_PARAMETERS_INCORRECT;
    }

    // 2. Mapeo de búferes de indicador
    SetIndexBuffer(0, BufferUpper, INDICATOR_DATA);
    SetIndexBuffer(1, BufferUpperColor, INDICATOR_COLOR_INDEX);
    SetIndexBuffer(2, BufferLower, INDICATOR_DATA);
    SetIndexBuffer(3, BufferLowerColor, INDICATOR_COLOR_INDEX);
    SetIndexBuffer(4, BufferBasis, INDICATOR_DATA);
    SetIndexBuffer(5, BufferBasisColor, INDICATOR_COLOR_INDEX);
    SetIndexBuffer(6, BufferTrend, INDICATOR_CALCULATIONS);

    // 3. Inicialización de valores vacíos y arrays
    PlotIndexSetDouble(0, PLOT_EMPTY_VALUE, EMPTY_VALUE);
    PlotIndexSetDouble(1, PLOT_EMPTY_VALUE, EMPTY_VALUE); 
    PlotIndexSetDouble(2, PLOT_EMPTY_VALUE, EMPTY_VALUE); 
    
    ArrayInitialize(BufferUpper, EMPTY_VALUE);
    ArrayInitialize(BufferLower, EMPTY_VALUE);
    ArrayInitialize(BufferBasis, EMPTY_VALUE);
    ArrayInitialize(BufferTrend, 1.0); // Asume tendencia alcista inicialmente

    // 4. Configuración visual para la ventana del indicador
    IndicatorSetInteger(INDICATOR_DIGITS, _Digits);
    string short_name = StringFormat("Donchian Trend (%d)", InpLength);
    IndicatorSetString(INDICATOR_SHORTNAME, short_name);

    // Evitar renderizar basura visual en las primeras velas
    PlotIndexSetInteger(0, PLOT_DRAW_BEGIN, InpLength);
    PlotIndexSetInteger(1, PLOT_DRAW_BEGIN, InpLength);
    PlotIndexSetInteger(2, PLOT_DRAW_BEGIN, InpLength);

    return INIT_SUCCEEDED;
}

//+------------------------------------------------------------------+
//| DEINIT FUNCTION                                                  |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
{
    // Limpieza de objetos gráficos y comentarios si existieran
    Comment("");
}

//+------------------------------------------------------------------+
//| CALCULATION FUNCTION                                             |
//+------------------------------------------------------------------+
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[])
{
    // Evitar cálculos si no hay suficientes barras
    if(rates_total < InpLength) return 0;

    // Determinar el índice de inicio optimizado
    int limit = prev_calculated == 0 ? InpLength - 1 : prev_calculated - 1;
    if (limit < InpLength - 1) limit = InpLength - 1;

    // Iteración principal (dirección estándar MQL5: de antiguo a reciente)
    for(int i = limit; i < rates_total; i++)
    {
        // 1. Encontrar Máximos y Mínimos en la ventana N
        double highest = high[i];
        double lowest = low[i];
        
        for(int j = 0; j < InpLength; j++)
        {
            if(high[i - j] > highest) highest = high[i - j];
            if(low[i - j] < lowest) lowest = low[i - j];
        }
        
        // 2. Asignación de datos matemáticos a los búferes
        BufferUpper[i] = highest;
        BufferLower[i] = lowest;
        BufferBasis[i] = (highest + lowest) / 2.0;
        
        // 3. Máquina de Estados (Trend Memory FSM)
        int current_trend = 1; // Valor por defecto
        
        if (i > InpLength - 1)
        {
            // Heredar el estado de la barra anterior (Memoria)
            current_trend = (int)BufferTrend[i-1]; 
            
            // Regla 1: Ruptura alcista contra el borde dinámico de la iteración previa
            if(BufferUpper[i-1] != EMPTY_VALUE && high[i] >= BufferUpper[i-1])
            {
                current_trend = 1;
            }
            // Regla 2: Ruptura bajista contra el borde dinámico de la iteración previa
            else if(BufferLower[i-1] != EMPTY_VALUE && low[i] <= BufferLower[i-1])
            {
                current_trend = -1;
            }
        }
        
        // Guardar estado
        BufferTrend[i] = current_trend;
        
        // 4. Transformación Gráfica (Color Routing)
        // color_idx 0 = clrLime, 1 = clrRed
        int color_idx = (current_trend == 1) ? 0 : 1;
        
        BufferUpperColor[i] = color_idx;
        BufferLowerColor[i] = color_idx;
        BufferBasisColor[i] = color_idx;
        
        // 5. Sistema de Alertas (Evaluado solo en el cierre de la vela para evitar repintado)
        if(InpEnableAlerts && i == rates_total - 2 && i > limit)
        {
            if(BufferTrend[i] != BufferTrend[i-1])
            {
                TriggerAlerts(current_trend, time[i]);
            }
        }
    }

    // Retornar número de barras calculadas para la siguiente iteración
    return rates_total;
}

//+------------------------------------------------------------------+
//| FUNCIONES AUXILIARES                                             |
//+------------------------------------------------------------------+

// Disparador multi-canal de alertas
void TriggerAlerts(int trend_state, datetime signal_time)
{
    // Filtrado de seguridad: solo una alerta por vela
    if(signal_time <= g_lastAlertTime) return; 
    g_lastAlertTime = signal_time;
    
    // Preparación del mensaje (ASCII únicamente)
    string trend_name = (trend_state == 1) ? "BULLISH" : "BEARISH";
    string msg = StringFormat("[Donchian Trend] %s %s - Trend shifted to %s", 
                              _Symbol, EnumToString((ENUM_TIMEFRAMES)_Period), trend_name);
                              
    // Ejecución de rutas de salida
    if(InpAlertPopup) Alert(msg);
    if(InpAlertSound) PlaySound("alert.wav");
    if(InpAlertPush)  SendNotification(msg);
    if(InpAlertEmail) SendMail("Donchian Trend Breakout", msg);
    
    // Registro en Journal
    Print(msg);
}

//+------------------------------------------------------------------+
//| REFERENCIA ORIGINAL PINE SCRIPT (DOCUMENTACIÓN INTERNA)          |
//+------------------------------------------------------------------+
/*
//@version=5
indicator("Donchian Channels Trend", overlay=true)

// --- Inputs ---
length = input.int(20, title="Length")

// --- Core Calculations ---
upper = ta.highest(high, length)
lower = ta.lowest(low, length)
basis = math.avg(upper, lower)

// --- State Machine ---
var int trend = 1

if high >= upper[1]
    trend := 1
else if low <= lower[1]
    trend := -1

// --- Coloring Output ---
col = trend == 1 ? color.lime : color.red

plot(upper, color=col, linewidth=2, title="Upper Band")
plot(lower, color=col, linewidth=2, title="Lower Band")
plot(basis, color=col, style=plot.style_dashdot, title="Basis Line")
*/