/*! \file xstream/dater.h
 *
 * \brief C++ objects to date output lines
 */

#ifndef __XSTREAM_DATER_H
#define __XSTREAM_DATER_H

#include <xstream/config.h>

#include <xstream/common.h>
#include <xstream/posix.h>

#include <streambuf>
#include <string>

namespace xstream{

/*!
 * \brief filter that add a time stamp on the begining of each line
 *
 */
class dater: public xstream::ostreambuf
{
	private:
		std::streambuf* _sb; /*!< streambuf were data is written to */
		posix::date_format date;
		char separator; /*!< data is written after this character */
		bool write_next;
		
		/*!
		 * \brief writes the current date to the streambuf
		 *
		 */
		void write_date();
		
		/*!
		 * \brief tries to write as much data as possible (overloaded from streambuf)
		 *
		 * */
		int sync();

		/*!
		 * \brief write a character that surpasses buffer end (overloaded from streambuf)
		 * 
		 */
		int overflow(const int c);

		/*!
		 * \brief write an entire buffer (overloaded from streambuf)
		 *
		 */
		std::streamsize xsputn(char *buffer, std::streamsize n);

	public:
		/*!
		 * \brief construct using another streambuf
		 *
		 * \param sb streambuf to write data to
		 * \param format format string for \c strftime defaults to [%c] the preferred date and time representation for the current locale
		 * \param separator character that signal a change of line, defaults to newline
		 * \param write_first if true date is written right before the first write. default is true
		 *
		 */

		dater(std::streambuf* sb, const std::string& format="[%c] ", const char separator='\n', const bool write_first=true);
		
		/*! destructor
		 *
		 * */
		~dater();
};

}//namespace xstream

#endif