/*
 * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
 *
 * This program is free software: you can use, redistribute, and/or modify
 * it under the terms of the GNU Affero General Public License, version 3
 * or later ("AGPL"), as published by the Free Software Foundation.
 *
 * This program 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.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef TDENGINE_QSCRIPT_H
#define TDENGINE_QSCRIPT_H
#ifdef LUA_EMBEDDED
#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>

#include "tutil.h"
#include "hash.h"
#include "tlist.h"
#include "qUdf.h"


#define USER_FUNC_NAME "funcName" 
#define USER_FUNC_NAME_LIMIT 48
/* define in this way to let others know that these two macros are logically related */
#define MAX_FUNC_NAME (USER_FUNC_NAME_LIMIT + 16)

enum ScriptState {
  SCRIPT_STATE_INIT,
  SCRIPT_STATE_ADD,
  SCRIPT_STATE_MERGE,
  SCRIPT_STATE_FINALIZE 
};


typedef struct {
  SHashObj  *funcId;    //func already registed in lua_env, may be no use
  lua_State *lua_state; // lua env 
} ScriptEnv;

typedef struct ScriptCtx {
  // one-more-space-for-null-terminator to support function name
  // at most USER_FUNC_NAME_LIMIT bytes long actually
  char       funcName[USER_FUNC_NAME_LIMIT + 1];
  int8_t     state;
  ScriptEnv *pEnv;
  int8_t     isAgg;  // agg function or not

  // init value of udf script
  int8_t   resType;
  uint16_t resBytes;

  int32_t numOfOutput;
  int32_t offset;

} ScriptCtx;

int taosLoadScriptInit(void *pInit);
void taosLoadScriptNormal(void *pInit, char *pInput, int16_t iType, uint16_t iBytes, int32_t numOfRows, 
    int64_t *ptsList, int64_t key, char* pOutput, char *ptsOutput, int32_t *numOfOutput, int16_t oType, uint16_t oBytes);
void taosLoadScriptFinalize(void *pInit, int64_t key, char *pOutput, int32_t *output);
void taosLoadScriptMerge(void *pCtx, char* data, int32_t numOfRows, char* dataOutput, int32_t* numOfOutput);
void taosLoadScriptDestroy(void *pInit);

typedef struct {
  SList     *scriptEnvs; //  
  int32_t   mSize;  // pool limit
  int32_t   cSize;  // current available size
  pthread_mutex_t mutex;
} ScriptEnvPool;

ScriptCtx* createScriptCtx(char *str, int8_t resType, uint16_t resBytes);
void       destroyScriptCtx(void *pScriptCtx);

int32_t scriptEnvPoolInit();
void    scriptEnvPoolCleanup();
bool    isValidScript(char *script, int32_t len);
#endif //LUA_EMBEDDED
#endif //TDENGINE_QSCRIPT_H 
