/*!
 * @file assert.h
 * @brief Contains assert macro for meowpp's debugging tools.
 *
 * You can use
 * @code{.cpp}
 * #define MEOWPP_NODEBUG
 * @endcode
 * to remove all the debugging code.
 *
 * @author cathook
 */

#ifndef __MEOWPP_ASSERT_H__
#define __MEOWPP_ASSERT_H__

#include <cstdio>
#include <cstdlib>


namespace meow {


/*!
 * @def Assert
 * @brief A macro for assert whether a expression is failed or not.
 * @param expr The expression to be tested.
 * @param ... Error information to be printed to stderr when the expr is failed.
 *
 * When expression is failed, it will call `fprintf(stderr, ...)` to print out
 * the message follows by calling `abort()` to halt the program.
 *
 * @note You can use
 * @code{.cpp}
 * #define MEOWPP_TESTING
 * @endcode
 * to tell this macro calls `test::abort()` instead of normal `abort()`
 * function.
 */


#ifndef MEOWPP_NODEBUG

#define MEOWPP_STRINGIFY(x) #x
#define MEOWPP_TOSTRING(x) MEOWPP_STRINGIFY(x)

#ifndef MEOWPP_DEBUG_ASSERT_TESTING

#define Assert(expr,...) \
  while (((expr) || \
          (fprintf(stderr, "Assertion error at " \
                   __FILE__ ":" MEOWPP_TOSTRING(__LINE__) \
                   " >>> " __VA_ARGS__), \
           abort(), false) + fprintf(stderr, "\n")) && false)

#else  // MEOWPP_DEBUG_ASSERT_TESTING

#define Assert(expr,...) \
  while (((expr) || \
          (fprintf(stderr, "Assertion error at " \
                   __FILE__ ":" MEOWPP_TOSTRING(__LINE__) \
                   " >>> " __VA_ARGS__), \
           test::abort(), false) + fprintf(stderr, "\n")) && false)

#endif  // MEOWPP_DEBUG_ASSERT_TESTING

#else  // MEOWPP_NODEBUG

#define Assert(expr,...) \
  while (false)

#endif  // MEOWPP_NODEBUG

}  // meow

#endif  // __MEOWPP_ASSERT_H__