/*
 * 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/>.
 */

#include "tsdbFSet2.h"

#ifndef _TSDB_FILE_SYSTEM_H
#define _TSDB_FILE_SYSTEM_H

#ifdef __cplusplus
extern "C" {
#endif

/* Exposed Handle */
typedef struct STFileSystem STFileSystem;
typedef struct STFSBgTask   STFSBgTask;
typedef TARRAY2(STFileSet *) TFileSetArray;

typedef enum {
  TSDB_FEDIT_COMMIT = 1,  //
  TSDB_FEDIT_MERGE
} EFEditT;

typedef enum {
  TSDB_BG_TASK_MERGER = 1,
  TSDB_BG_TASK_RETENTION,
  TSDB_BG_TASK_COMPACT,
} EFSBgTaskT;

typedef enum {
  TSDB_FCURRENT = 1,
  TSDB_FCURRENT_C,  // for commit
  TSDB_FCURRENT_M,  // for merge
} EFCurrentT;

/* Exposed APIs */
// open/close
int32_t tsdbOpenFS(STsdb *pTsdb, STFileSystem **fs, int8_t rollback);
int32_t tsdbCloseFS(STFileSystem **fs);
// snapshot
int32_t tsdbFSCreateCopySnapshot(STFileSystem *fs, TFileSetArray **fsetArr);
int32_t tsdbFSDestroyCopySnapshot(TFileSetArray **fsetArr);
int32_t tsdbFSCreateRefSnapshot(STFileSystem *fs, TFileSetArray **fsetArr);
int32_t tsdbFSDestroyRefSnapshot(TFileSetArray **fsetArr);
// txn
int64_t tsdbFSAllocEid(STFileSystem *fs);
int32_t tsdbFSEditBegin(STFileSystem *fs, const TFileOpArray *opArray, EFEditT etype);
int32_t tsdbFSEditCommit(STFileSystem *fs);
int32_t tsdbFSEditAbort(STFileSystem *fs);
// background task
int32_t tsdbFSScheduleBgTask(STFileSystem *fs, EFSBgTaskT type, int32_t (*run)(void *), void *arg, int64_t *taskid);
int32_t tsdbFSWaitBgTask(STFileSystem *fs, int64_t taskid);
int32_t tsdbFSWaitAllBgTask(STFileSystem *fs);
// other
int32_t tsdbFSGetFSet(STFileSystem *fs, int32_t fid, STFileSet **fset);

struct STFSBgTask {
  EFSBgTaskT type;
  int32_t (*run)(void *arg);
  void *arg;

  TdThreadCond done[1];
  int32_t      numWait;

  int64_t taskid;
  int64_t scheduleTime;
  int64_t launchTime;
  int64_t finishTime;

  struct STFSBgTask *prev;
  struct STFSBgTask *next;
};

/* Exposed Structs */
struct STFileSystem {
  STsdb        *tsdb;
  tsem_t        canEdit;
  int32_t       state;
  int64_t       neid;
  EFEditT       etype;
  TFileSetArray fSetArr[1];
  TFileSetArray fSetArrTmp[1];

  // background task queue
  TdThreadMutex mutex[1];
  bool          stop;
  int64_t       taskid;
  int32_t       bgTaskNum;
  STFSBgTask    bgTaskQueue[1];
  STFSBgTask   *bgTaskRunning;
};

#ifdef __cplusplus
}
#endif

#endif /*_TSDB_FILE_SYSTEM_H*/