#ifndef __LOGGER_H__
#define __LOGGER_H__

/**
 * ログを簡単にとるための道具
 * 
 */

#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>

class Loggable{
  public:
    virtual void inspect(std::ostream &out) const = 0;
};

class Logger{
  protected:
    typedef std::ostream ostream;
    typedef std::fstream fstream;
    typedef std::string string;
    typedef std::vector<const Loggable *> storage_t;
    std::ostream &m_out;
    storage_t m_targets;
    bool do_make_stream;
  public:
    Logger() : m_out(std::cout), m_targets(), do_make_stream(false) {}
    Logger(ostream &out) : m_out(out), m_targets(), do_make_stream(false) {}
    Logger(string fname) 
      : m_out(*(new fstream(fname.c_str(), std::ios::out | std::ios::app))), 
        m_targets(),
        do_make_stream(true) {}
    ~Logger(){
      if(do_make_stream){
        (static_cast<std::fstream *>(&m_out))->close();
        delete(&m_out);
      }
    }
    
    std::ostream &out() const {return m_out;}
    
    void flush() const{
      for(storage_t::const_iterator it = m_targets.begin(); it < m_targets.end(); it++){
        (*it)->inspect(m_out);
      }
    }
    
    void add(const Loggable &target){
      m_targets.push_back(&target);
    }
    void remove(const Loggable &target){
      m_targets.erase(std::remove(m_targets.begin(), m_targets.end(), &target), m_targets.end());
    }
    void clear(){m_targets.clear();}
};

#endif /* __LOGGER_H__ */