#ifndef COMPAT53_H_
#define COMPAT53_H_

#include <stddef.h>
#include <limits.h>
#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>


#if defined(COMPAT53_PREFIX)
/* - change the symbol names of functions to avoid linker conflicts
 * - compat-5.3.c needs to be compiled (and linked) separately
 */
#  if !defined(COMPAT53_API)
#    define COMPAT53_API extern
#  endif
#  undef COMPAT53_INCLUDE_SOURCE
#else /* COMPAT53_PREFIX */
/* - make all functions static and include the source.
 * - don't mess with the symbol names of functions
 * - compat-5.3.c doesn't need to be compiled (and linked) separately
 */
#  define COMPAT53_PREFIX lua
#  undef COMPAT53_API
#  if defined(__GNUC__) || defined(__clang__)
#    define COMPAT53_API __attribute__((__unused__)) static
#  else
#    define COMPAT53_API static
#  endif
#  define COMPAT53_INCLUDE_SOURCE
#endif /* COMPAT53_PREFIX */

#define COMPAT53_CONCAT_HELPER(a, b) a##b
#define COMPAT53_CONCAT(a, b) COMPAT53_CONCAT_HELPER(a, b)



/* declarations for Lua 5.1 */
#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM == 501

/* XXX not implemented:
 * lua_arith
 * lua_compare
 * lua_upvalueid
 * lua_upvaluejoin
 * lua_version
 * lua_yieldk
 * luaL_buffinitsize
 * luaL_execresult
 * luaL_loadbufferx
 * luaL_loadfilex
 * luaL_prepbuffsize
 * luaL_pushresultsize
 */

/* PUC-Rio Lua uses lconfig_h as include guard for luaconf.h,
 * LuaJIT uses luaconf_h. If you use PUC-Rio's include files
 * but LuaJIT's library, you will need to define the macro
 * COMPAT53_IS_LUAJIT yourself! */
#if !defined(COMPAT53_IS_LUAJIT) && defined(luaconf_h)
#  define COMPAT53_IS_LUAJIT
#endif

#define LUA_OK 0

typedef struct luaL_Stream {
  FILE *f;
  lua_CFunction closef;
} luaL_Stream;

typedef size_t lua_Unsigned;

#define lua_absindex COMPAT53_CONCAT(COMPAT53_PREFIX, _absindex)
COMPAT53_API int lua_absindex (lua_State *L, int i);

#define lua_copy COMPAT53_CONCAT(COMPAT53_PREFIX, _copy)
COMPAT53_API void lua_copy (lua_State *L, int from, int to);

#define lua_getuservalue(L, i) \
  (lua_getfenv(L, i), lua_type(L, -1))
#define lua_setuservalue(L, i) \
  (luaL_checktype(L, -1, LUA_TTABLE), lua_setfenv(L, i))

#define lua_len COMPAT53_CONCAT(COMPAT53_PREFIX, _len)
COMPAT53_API void lua_len (lua_State *L, int i);

#define luaL_newlibtable(L, l) \
  (lua_createtable(L, 0, sizeof(l)/sizeof(*(l))-1))
#define luaL_newlib(L, l) \
  (luaL_newlibtable(L, l), luaL_register(L, NULL, l))

#define lua_pushglobaltable(L) \
  lua_pushvalue(L, LUA_GLOBALSINDEX)

#define lua_rawgetp COMPAT53_CONCAT(COMPAT53_PREFIX, _rawgetp)
COMPAT53_API int lua_rawgetp (lua_State *L, int i, const void *p);

#define lua_rawsetp COMPAT53_CONCAT(COMPAT53_PREFIX, _rawsetp)
COMPAT53_API void lua_rawsetp(lua_State *L, int i, const void *p);

#define lua_rawlen(L, i) lua_objlen(L, i)

#define lua_tointegerx COMPAT53_CONCAT(COMPAT53_PREFIX, _tointegerx)
COMPAT53_API lua_Integer lua_tointegerx (lua_State *L, int i, int *isnum);

#define lua_tonumberx COMPAT53_CONCAT(COMPAT53_PREFIX, _tonumberx)
COMPAT53_API lua_Number lua_tonumberx (lua_State *L, int i, int *isnum);

#define luaL_checkversion COMPAT53_CONCAT(COMPAT53_PREFIX, L_checkversion)
COMPAT53_API void luaL_checkversion (lua_State *L);

#define luaL_getsubtable COMPAT53_CONCAT(COMPAT53_PREFIX, L_getsubtable)
COMPAT53_API int luaL_getsubtable (lua_State* L, int i, const char *name);

#define luaL_len COMPAT53_CONCAT(COMPAT53_PREFIX, L_len)
COMPAT53_API int luaL_len (lua_State *L, int i);

#define luaL_setfuncs COMPAT53_CONCAT(COMPAT53_PREFIX, L_setfuncs)
COMPAT53_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup);

#define luaL_setmetatable COMPAT53_CONCAT(COMPAT53_PREFIX, L_setmetatable)
COMPAT53_API void luaL_setmetatable (lua_State *L, const char *tname);

#define luaL_testudata COMPAT53_CONCAT(COMPAT53_PREFIX, L_testudata)
COMPAT53_API void *luaL_testudata (lua_State *L, int i, const char *tname);

#define luaL_tolstring COMPAT53_CONCAT(COMPAT53_PREFIX, L_tolstring)
COMPAT53_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len);

#if !defined(COMPAT53_IS_LUAJIT)
#define luaL_traceback COMPAT53_CONCAT(COMPAT53_PREFIX, L_traceback)
COMPAT53_API void luaL_traceback (lua_State *L, lua_State *L1, const char *msg, int level);

#define luaL_fileresult COMPAT53_CONCAT(COMPAT53_PREFIX, L_fileresult)
COMPAT53_API int luaL_fileresult (lua_State *L, int stat, const char *fname);
#endif /* COMPAT53_IS_LUAJIT */

#define lua_callk(L, na, nr, ctx, cont) \
  ((void)(ctx), (void)(cont), lua_call(L, na, nr))
#define lua_pcallk(L, na, nr, err, ctx, cont) \
  ((void)(ctx), (void)(cont), lua_pcall(L, na, nr, err))

#if defined(LUA_COMPAT_APIINTCASTS)
#define lua_pushunsigned(L, n) \
  lua_pushinteger(L, (lua_Integer)(n))
#define lua_tounsignedx(L, i, is) \
  ((lua_Unsigned)lua_tointegerx(L, i, is))
#define lua_tounsigned(L, i) \
  lua_tounsignedx(L, i, NULL)
#define luaL_checkunsigned(L, a) \
  ((lua_Unsigned)luaL_checkinteger(L, a))
#define luaL_optunsigned(L, a, d) \
  ((lua_Unsigned)luaL_optinteger(L, a, (lua_Integer)(d)))
#endif

#endif /* Lua 5.1 only */



/* declarations for Lua 5.1 and 5.2 */
#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM <= 502

typedef int lua_KContext;

typedef int (*lua_KFunction)(lua_State *L, int status, lua_KContext ctx);

#define lua_dump(L, w, d, s) \
  ((void)(s), lua_dump(L, w, d))

#define lua_getfield(L, i, k) \
  (lua_getfield(L, i, k), lua_type(L, -1))

#define lua_gettable(L, i) \
  (lua_gettable(L, i), lua_type(L, -1))

#define lua_geti COMPAT53_CONCAT(COMPAT53_PREFIX, _geti)
COMPAT53_API int lua_geti (lua_State *L, int index, lua_Integer i);

#define lua_isinteger COMPAT53_CONCAT(COMPAT53_PREFIX, _isinteger)
COMPAT53_API int lua_isinteger (lua_State *L, int index);

#define lua_numbertointeger(n, p) \
  ((*(p) = (lua_Integer)(n)), 1)

#define lua_rawget(L, i) \
  (lua_rawget(L, i), lua_type(L, -1))

#define lua_rawgeti(L, i, n) \
  (lua_rawgeti(L, i, n), lua_type(L, -1))

#define lua_rotate COMPAT53_CONCAT(COMPAT53_PREFIX, _rotate)
COMPAT53_API void lua_rotate (lua_State *L, int idx, int n);

#define lua_seti COMPAT53_CONCAT(COMPAT53_PREFIX, _seti)
COMPAT53_API void lua_seti (lua_State *L, int index, lua_Integer i);

#define lua_strtonum COMPAT53_CONCAT(COMPAT53_PREFIX, _stringtonumber)
COMPAT53_API size_t lua_stringtonumber (lua_State *L, const char *s);

#define luaL_getmetafield(L, o, e) \
  (luaL_getmetafield(L, o, e) ? lua_type(L, -1) : LUA_TNIL)

#define luaL_requiref COMPAT53_CONCAT(COMPAT53_PREFIX, L_requiref_)
COMPAT53_API void luaL_requiref (lua_State *L, const char *modname,
                                 lua_CFunction openf, int glb );

#endif /* Lua 5.1 and Lua 5.2 */



/* declarations for Lua 5.2 */
#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM == 502

/* XXX not implemented:
 * lua_isyieldable
 * lua_getextraspace
 * lua_arith (new operators)
 * lua_pushfstring (new formats)
 */

#define lua_getglobal(L, n) \
  (lua_getglobal(L, n), lua_type(L, -1))

#define lua_getuservalue(L, i) \
  (lua_getuservalue(L, i), lua_type(L, -1))

#define lua_rawgetp(L, i, p) \
  (lua_rawgetp(L, i, p), lua_type(L, -1))

#define LUA_KFUNCTION(_name) \
  static int (_name)(lua_State *L, int status, lua_KContext ctx); \
  static int (_name ## _52)(lua_State *L) { \
    luaK_Context ctx; \
    int status = lua_getctx(L, &ctx); \
    return (_name)(L, status, ctx); \
  } \
  static int (_name)(lua_State *L, int status, lua_KContext ctx)

#define lua_pcallk(L, na, nr, err, ctx, cont) \
  lua_pcallk(L, na, nr, err, ctx, cont ## _52)

#define lua_callk(L, na, nr, ctx, cont) \
  lua_callk(L, na, nr, ctx, cont ## _52)

#define lua_yieldk(L, nr, ctx, cont) \
  lua_yieldk(L, nr, ctx, cont ## _52)

#ifdef lua_call
#  undef lua_call
#  define lua_call(L, na, nr) \
  (lua_callk)(L, na, nr, 0, NULL)
#endif

#ifdef lua_pcall
#  undef lua_pcall
#  define lua_pcall(L, na, nr, err) \
  (lua_pcallk)(L, na, nr, err, 0, NULL)
#endif

#ifdef lua_yield
#  undef lua_yield
#  define lua_yield(L, nr) \
  (lua_yieldk)(L, nr, 0, NULL)
#endif

#endif /* Lua 5.2 only */



/* other Lua versions */
#if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM < 501 || LUA_VERSION_NUM > 503

#  error "unsupported Lua version (i.e. not Lua 5.1, 5.2, or 5.3)"

#endif /* other Lua versions except 5.1, 5.2, and 5.3 */



/* helper macro for defining continuation functions (for every version
 * *except* Lua 5.2) */
#ifndef LUA_KFUNCTION
#define LUA_KFUNCTION(_name) \
  static int (_name)(lua_State *L, int status, lua_KContext ctx)
#endif


#if defined(COMPAT53_INCLUDE_SOURCE)
#  include "compat-5.3.c"
#endif


#endif /* COMPAT53_H_ */