/***********************************************************************
* flog.h - Interface of the FINAL CUT logger                           *
*                                                                      *
* This file is part of the Final Cut widget toolkit                    *
*                                                                      *
* Copyright 2020 Markus Gans                                           *
*                                                                      *
* The Final Cut is free software; you can redistribute it and/or       *
* modify it under the terms of the GNU Lesser General Public License   *
* as published by the Free Software Foundation; either version 3 of    *
* the License, or (at your option) any later version.                  *
*                                                                      *
* The Final Cut is distributed in the hope that it will be useful,     *
* but WITHOUT ANY WARRANTY; without even the implied warranty of       *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
* GNU Lesser General Public License for more details.                  *
*                                                                      *
* You should have received a copy of the GNU Lesser General Public     *
* License along with this program.  If not, see                        *
* <http://www.gnu.org/licenses/>.                                      *
***********************************************************************/

/*  Standalone class
 *  ════════════════
 *
 * ▕▔▔▔▔▔▔▏
 * ▕ FLog ▏
 * ▕▁▁▁▁▁▁▏
 */

#ifndef FLOG_H
#define FLOG_H

#if !defined (USE_FINAL_H) && !defined (COMPILE_FINAL_CUT)
  #error "Only <final/final.h> can be included directly."
#endif

#include <functional>
#include <iostream>
#include <ostream>
#include <sstream>
#include <string>

#include <final/fstring.h>

namespace finalcut
{

using namespace std::placeholders;

//----------------------------------------------------------------------
// class FLog
//----------------------------------------------------------------------

class FLog : public std::stringbuf
{
  public:
    // Using-declaration
    using FLogPrint = std::function<void(const std::string&)>;

    // Enumerations
    enum LogLevel
    {
      Info, Warn, Error, Debug
    };

    enum LineEnding
    {
      LF, CR, CRLF
    };


    // Constructor
    FLog();

    // Destructor
    ~FLog() override;

    template <typename T>
    FLog& operator << (const T& s);
    FLog& operator << (std::ostream&(*)(std::ostream&));
    FLog& operator << (LogLevel);

    virtual const FString getClassName() const;
    virtual void info (const std::string&) = 0;
    virtual void warn (const std::string&) = 0;
    virtual void error (const std::string&) = 0;
    virtual void debug (const std::string&) = 0;
    virtual void setOutputStream (const std::ostream&) = 0;
    virtual void setLineEnding (LineEnding) = 0;
    virtual void enableTimestamp() = 0;
    virtual void disableTimestamp() = 0;

  protected:
    int sync() override;

    // Data member
    LogLevel   level{Info};
    LineEnding end_of_line{CRLF};

  private:
    // Data member
    FLogPrint    current_log{std::bind(&FLog::info, this, _1)};
    std::ostream stream{this};
};

// FLog inline functions
//----------------------------------------------------------------------
template <typename T>
inline FLog& FLog::operator << (const T& s)
{
  stream << s;
  return *this;
}

//----------------------------------------------------------------------
inline FLog& FLog::operator << (std::ostream&(*pf)(std::ostream&))
{
  pf(stream);
  return *this;
}

//----------------------------------------------------------------------
inline const FString FLog::getClassName() const
{ return "FLog"; }

}  // namespace finalcut

#endif  // FLOG_H