//+------------------------------------------------------------------+
//|                                             MoneyFixedMargin.mqh |
//|                             Copyright 2000-2025, MetaQuotes Ltd. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#include <Expert\ExpertMoney.mqh>
// wizard description start
//+------------------------------------------------------------------+
//| Description of the class                                         |
//| Title=Trading with fixed margin                                  |
//| Type=Money                                                       |
//| Name=FixMargin                                                   |
//| Class=CMoneyFixedMargin                                          |
//| Page=                                                            |
//| Parameter=Percent,double,10.0,Percentage of margin               |
//+------------------------------------------------------------------+
// wizard description end
//+------------------------------------------------------------------+
//| Class CMoneyFixedMargin.                                         |
//| Purpose: Class of money management with fixed percent margin.    |
//|              Derives from class CExpertMoney.                    |
//+------------------------------------------------------------------+
class CMoneyFixedMargin : public CExpertMoney
  {
public:
                     CMoneyFixedMargin(void);
                    ~CMoneyFixedMargin(void);
   //---
   virtual double    CheckOpenLong(double price,double sl);
   virtual double    CheckOpenShort(double price,double sl);
  };
//+------------------------------------------------------------------+
//| Constructor                                                      |
//+------------------------------------------------------------------+
void CMoneyFixedMargin::CMoneyFixedMargin(void)
  {
  }
//+------------------------------------------------------------------+
//| Destructor                                                       |
//+------------------------------------------------------------------+
void CMoneyFixedMargin::~CMoneyFixedMargin(void)
  {
  }
//+------------------------------------------------------------------+
//| Getting lot size for open long position.                         |
//+------------------------------------------------------------------+
double CMoneyFixedMargin::CheckOpenLong(double price,double sl)
  {
   if(m_symbol==NULL)
      return(0.0);
//--- select lot size
   double lot;
   if(price==0.0)
      lot=m_account.MaxLotCheck(m_symbol.Name(),ORDER_TYPE_BUY,m_symbol.Ask(),m_percent);
   else
      lot=m_account.MaxLotCheck(m_symbol.Name(),ORDER_TYPE_BUY,price,m_percent);
//--- return trading volume
   return(lot);
  }
//+------------------------------------------------------------------+
//| Getting lot size for open short position.                        |
//+------------------------------------------------------------------+
double CMoneyFixedMargin::CheckOpenShort(double price,double sl)
  {
   if(m_symbol==NULL)
      return(0.0);
//--- select lot size
   double lot;
   if(price==0.0)
      lot=m_account.MaxLotCheck(m_symbol.Name(),ORDER_TYPE_SELL,m_symbol.Bid(),m_percent);
   else
      lot=m_account.MaxLotCheck(m_symbol.Name(),ORDER_TYPE_SELL,price,m_percent);
//--- return trading volume
   return(lot);
  }
//+------------------------------------------------------------------+