/*
 * 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 _TD_WAL_H_
#define _TD_WAL_H_

#ifdef __cplusplus
extern "C" {
#endif

#define WAL_SIGNATURE  ((uint32_t)(0xFAFBFDFE))
#define WAL_MAX_SIZE   (TSDB_MAX_WAL_SIZE + sizeof(SWalHead) + 16)

typedef enum {
  TAOS_WAL_NOLOG = 0,
  TAOS_WAL_WRITE = 1,
  TAOS_WAL_FSYNC = 2
} EWalType;

typedef enum {
  TAOS_WAL_NOT_KEEP = 0,
  TAOS_WAL_KEEP = 1
} EWalKeep;

typedef struct {
  int8_t   msgType;
  int8_t   sver;  // sver 2 for WAL SDataRow/SMemRow compatibility
  int8_t   reserved[2];
  int32_t  len;
  uint64_t version;
  uint32_t signature;
  uint32_t cksum;
  char     cont[];
} SWalHead;

typedef struct {
  int32_t  vgId;
  int32_t  fsyncPeriod;  // millisecond
  EWalType walLevel;     // wal level
  EWalKeep keep;         // keep the wal file when closed
} SWalCfg;

typedef void *  twalh;  // WAL HANDLE
typedef int32_t FWalWrite(void *ahandle, void *pHead, int32_t qtype, void *pMsg);

int32_t  walInit();
void     walCleanUp();
twalh    walOpen(char *path, SWalCfg *pCfg);
int32_t  walAlter(twalh pWal, SWalCfg *pCfg);
void     walStop(twalh);
void     walClose(twalh);
int32_t  walRenew(twalh);
void     walRemoveOneOldFile(twalh);
void     walRemoveAllOldFiles(twalh);
int32_t  walWrite(twalh, SWalHead *);
void     walFsync(twalh, bool forceFsync);
int32_t  walRestore(twalh, void *pVnode, FWalWrite writeFp);
int32_t  walGetWalFile(twalh, char *fileName, int64_t *fileId);
uint64_t walGetVersion(twalh);
void     walResetVersion(twalh, uint64_t newVer);
int64_t  walGetFSize(twalh);

#ifdef __cplusplus
}
#endif

#endif  // _TD_WAL_H_
