log.h

#ifndef GM_LOG_H
#define GM_LOG_H

#include <iostream>

namespace GNUMessenger {
using namespace std;

#define LOG(x) { Log << x << endl; }
#define LOG_DEBUG(x) { Log.Debug() << x << " ["__FILE__"(" << __LINE__ << ")]" << endl; }

class LogBase
{
public:

    LogBase();
    
    virtual LogBase& operator <<(ostream& ( *pf )(ostream&)){
        pf(GetStream());
        return *this;
    }
    
    virtual LogBase& operator <<(const wchar_t * wstr){
        GetStreamW() << wstr;
        return *this;
    }
    
    virtual LogBase& operator <<(const char * str){
        GetStream() << str;
        return *this;
    } 

    template <typename T>
    LogBase& operator << (const T str) {
        GetStream() << str;
        return *this;
    }
    
    enum Mode { Debug, Error, Normal };

    const char * GetMode();
    
    virtual void SetMode(const Mode mode);
    
protected:

    virtual void Break() { m_lastWasWide = true; }
    virtual void BreakW() { m_lastWasWide = false; }

    virtual ostream& GetStream() = 0;
    virtual wostream& GetStreamW()= 0;
    
    Mode m_mode;
    
private:
    bool m_lastWasWide;
};

class StdLog: public LogBase
{
public:

    virtual void SetMode(const Mode mode) { 
        LogBase::SetMode(mode);
        (*this) << GetMode();
    }
    
protected:

    virtual ostream& GetStream() { return cout; }
    virtual wostream& GetStreamW() { return wcout; }

};

class LogNull: public LogBase
{
public:
protected:

    virtual ostream& GetStream() { return cout; }
    virtual wostream& GetStreamW() { return wcout; }
};

class LogManager {
public:

    LogManager();
    
    ~LogManager();
    
    void SetLog(LogBase * logger);
    
    LogBase * GetLog() { return m_logger; }
    
    LogBase& operator << (const char * str);
    
    LogBase& operator << (const wchar_t* wstr);
    
    LogBase& Debug();
    
    LogBase& Error();
    
    LogBase& Normal();
    
private:
    LogBase * m_logger;

};

static LogManager Log = LogManager(); 

}

#endif

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