/*******************************************************************************

 Copyright (c) 2009, Charles McGarvey
 All rights reserved.
 
 Redistribution   and   use  in  source  and  binary  forms,  with  or  without
 modification, are permitted provided that the following conditions are met:
 
   * Redistributions  of  source  code  must retain the above copyright notice,
     this list of conditions and the following disclaimer.
   * Redistributions  in binary form must reproduce the above copyright notice,
     this  list of conditions and the following disclaimer in the documentation
     and/or other materials provided with the distribution.
 
 THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 AND  ANY  EXPRESS  OR  IMPLIED  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 DISCLAIMED.  IN  NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 FOR  ANY  DIRECT,  INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 DAMAGES  (INCLUDING,  BUT  NOT  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 SERVICES;  LOSS  OF  USE,  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 CAUSED  AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 OR  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*******************************************************************************/

#ifndef _MOOF_LOG_H_
#define _MOOF_LOG_H_

/**
 * @file log.h
 * Functions related to logging the process.
 * The logging functions are logError(), logWarning(), logInfo(), and
 * logDebug(), listed from most critical to least critical.
 */

#include <cstdlib>		// exit


/**
 * Macro which tests an assertion and issues an logError() and exits if false.
 * @param X test to perform
 */

#if ! NDEBUG
#define ASSERT(X) if (!(X)) Mf::logError("false assertion at %s:%d, " #X, \
		__FILE__, __LINE__), exit(1)
#else
#define ASSERT(X)
#endif


namespace Mf {


/**
 * Possible values used for setting the log level using LogLevel().  Log
 * messages of lesser importance than the level specified are ignored.
 * @see LogLevel()
 */

enum LogLevel
{
	LOG_NONE		= -1,		///< Disable all logging.
	LOG_ERROR		=  1,		///< Log only errors.
	LOG_WARNING		=  2,		///< Log warnings and errors.
	LOG_INFO		=  3,		///< Log info, warnings, errors.
	LOG_DEBUG		=  4		///< Log all messages.
};


/**
 * Set and/or get the level of logs which will be logged.  If not called,
 * defaults to WARNING
 * @param level LOG_LEVEL_* constant or 0 for no change.
 * @return The currently set log level.
 */

LogLevel setLogLevel(LogLevel level);


/**
 * Log an error.
 * @param fmt Log format string.
 * @param ... Extra format arguments.
 */

void logError(const char* fmt, ...);

/**
 * Log a warning.
 * @param fmt Log format string.
 * @param ... Extra format arguments.
 */

void logWarning(const char* fmt, ...);

/**
 * Log a message.
 * @param fmt Log format string.
 * @param ... Extra format arguments.
 */

void logInfo(const char* fmt, ...);

/**
 * Log a debug message.
 * @param fmt Log format string.
 * @param ... Extra format arguments.
 */

void logDebug(const char* fmt, ...);


} // namespace Mf

#endif // _MOOF_LOG_H_