/*
 * 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_TFS_H
#define TD_TFS_H

#include "tglobal.h"

#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
  int level;
  int id;
} SDiskID;

#define TFS_UNDECIDED_LEVEL -1
#define TFS_UNDECIDED_ID -1
#define TFS_PRIMARY_LEVEL 0
#define TFS_PRIMARY_ID 0
#define TFS_MIN_LEVEL 0
#define TFS_MAX_LEVEL (TSDB_MAX_TIERS - 1)

// FS APIs ====================================
typedef struct {
  int64_t tsize;
  int64_t used;
  int64_t avail;
} SFSMeta;

typedef struct {
  int64_t size;
  int64_t used;
  int64_t free;
  int16_t nAvailDisks;  // # of Available disks
} STierMeta;

int  tfsInit(SDiskCfg *pDiskCfg, int ndisk);
void tfsDestroy();
void tfsUpdateInfo(SFSMeta *pFSMeta, STierMeta *tierMetas, int8_t numLevels);
void tfsGetMeta(SFSMeta *pMeta);
void tfsAllocDisk(int expLevel, int *level, int *id);

const char *TFS_PRIMARY_PATH();
const char *TFS_DISK_PATH(int level, int id);

// TFILE APIs ====================================
typedef struct {
  int  level;
  int  id;
  char rname[TSDB_FILENAME_LEN];  // REL name
  char aname[TSDB_FILENAME_LEN];  // ABS name
} TFILE;

#define TFILE_LEVEL(pf) ((pf)->level)
#define TFILE_ID(pf) ((pf)->id)
#define TFILE_NAME(pf) ((pf)->aname)
#define TFILE_REL_NAME(pf) ((pf)->rname)

#define tfsopen(pf, flags) open(TFILE_NAME(pf), flags)
#define tfsclose(fd) close(fd)
#define tfsremove(pf) remove(TFILE_NAME(pf))
#define tfscopy(sf, df) taosCopyFile(TFILE_NAME(sf), TFILE_NAME(df))
#define tfsrename(sf, df) taosRename(TFILE_NAME(sf), TFILE_NAME(df))

void  tfsInitFile(TFILE *pf, int level, int id, const char *bname);
bool  tfsIsSameFile(const TFILE *pf1, const TFILE *pf2);
int   tfsEncodeFile(void **buf, TFILE *pf);
void *tfsDecodeFile(void *buf, TFILE *pf);
void  tfsbasename(const TFILE *pf, char *dest);
void  tfsdirname(const TFILE *pf, char *dest);

// DIR APIs ====================================
int tfsMkdirAt(const char *rname, int level, int id);
int tfsMkdirRecurAt(const char *rname, int level, int id);
int tfsMkdir(const char *rname);
int tfsRmdir(const char *rname);
int tfsRename(char *orname, char *nrname);

typedef struct TDIR TDIR;

TDIR *       tfsOpendir(const char *rname);
const TFILE *tfsReaddir(TDIR *tdir);
void         tfsClosedir(TDIR *tdir);

#ifdef __cplusplus
}
#endif

#endif
