/*
 * 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_TUDF_H
#define TDENGINE_TUDF_H

enum {
  TSDB_UDF_FUNC_NORMAL = 0,
  TSDB_UDF_FUNC_INIT,
  TSDB_UDF_FUNC_FINALIZE,
  TSDB_UDF_FUNC_MERGE,
  TSDB_UDF_FUNC_DESTROY,
  TSDB_UDF_FUNC_MAX_NUM
};

typedef struct SUdfInit {
  int32_t  maybe_null; /* 1 if function can return NULL */
  uint32_t decimals;   /* for real functions */
  uint64_t length;     /* For string functions */
  char*    ptr;        /* free pointer for function data */
  int32_t  const_item; /* 0 if result is independent of arguments */

  // script like lua/javascript
  void* script_ctx;
  void (*destroyCtxFunc)(void* script_ctx);
} SUdfInit;

typedef struct SUdfInfo {
  int32_t functionId;                    // system assigned function id
  int32_t funcType;                      // scalar function or aggregate function
  int8_t  resType;                       // result type
  int16_t resBytes;                      // result byte
  int32_t contLen;                       // content length
  int32_t bufSize;                       // interbuf size
  char*   name;                          // function name
  void*   handle;                        // handle loaded in mem
  void*   funcs[TSDB_UDF_FUNC_MAX_NUM];  // function ptr

  // for script like lua/javascript only
  int   isScript;
  void* pScriptCtx;

  SUdfInit init;
  char*    content;
  char*    path;
} SUdfInfo;

// script

typedef int32_t (*scriptInitFunc)(void* pCtx);
typedef void (*scriptNormalFunc)(void* pCtx, char* data, int16_t iType, int16_t iBytes, int32_t numOfRows,
                                 int64_t* ptList, int64_t key, char* dataOutput, char* tsOutput, int32_t* numOfOutput,
                                 int16_t oType, int16_t oBytes);
typedef void (*scriptFinalizeFunc)(void* pCtx, int64_t key, char* dataOutput, int32_t* numOfOutput);
typedef void (*scriptMergeFunc)(void* pCtx, char* data, int32_t numOfRows, char* dataOutput, int32_t* numOfOutput);
typedef void (*scriptDestroyFunc)(void* pCtx);

// dynamic lib
typedef void (*udfNormalFunc)(char* data, int16_t itype, int16_t iBytes, int32_t numOfRows, int64_t* ts,
                              char* dataOutput, char* interBuf, char* tsOutput, int32_t* numOfOutput, int16_t oType,
                              int16_t oBytes, SUdfInit* buf);
typedef int32_t (*udfInitFunc)(SUdfInit* data);
typedef void (*udfFinalizeFunc)(char* dataOutput, char* interBuf, int32_t* numOfOutput, SUdfInit* buf);
typedef void (*udfMergeFunc)(char* data, int32_t numOfRows, char* dataOutput, int32_t* numOfOutput, SUdfInit* buf);
typedef void (*udfDestroyFunc)(SUdfInit* buf);

#endif  // TDENGINE_TUDF_H