/*
 * 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/>.
 */

#define _DEFAULT_SOURCE
#include "os.h"
#include "taoserror.h"
#include "taosmsg.h"
#include "tglobal.h"
#include "tfs.h"
#include "query.h"
#include "dnode.h"
#include "vnodeCfg.h"
#include "vnodeStatus.h"
#include "vnodeSync.h"
#include "vnodeVersion.h"
#include "vnodeMgmt.h"
#include "vnodeWorker.h"
#include "vnodeBackup.h"
#include "vnodeMain.h"

static int32_t vnodeProcessTsdbStatus(void *arg, int32_t status, int32_t eno);

int32_t vnodeCreate(SCreateVnodeMsg *pVnodeCfg) {
  int32_t code;

  SVnodeObj *pVnode = vnodeAcquire(pVnodeCfg->cfg.vgId);
  if (pVnode != NULL) {
    vDebug("vgId:%d, vnode already exist, refCount:%d pVnode:%p", pVnodeCfg->cfg.vgId, pVnode->refCount, pVnode);
    vnodeRelease(pVnode);
    return TSDB_CODE_SUCCESS;
  }

  if (tfsMkdir("vnode") < 0) {
    vError("vgId:%d, failed to create vnode dir, reason:%s", pVnodeCfg->cfg.vgId, tstrerror(terrno));
    return terrno;
  }

  char rootDir[TSDB_FILENAME_LEN] = {0};
  sprintf(rootDir, "%s/vnode%d", tsVnodeDir, pVnodeCfg->cfg.vgId);

  char vnodeDir[TSDB_FILENAME_LEN] = "\0";
  snprintf(vnodeDir, TSDB_FILENAME_LEN, "/vnode/vnode%d", pVnodeCfg->cfg.vgId);
  if (tfsMkdir(vnodeDir) < 0) {
    vError("vgId:%d, failed to create vnode dir %s, reason:%s", pVnodeCfg->cfg.vgId, vnodeDir, strerror(errno));
    return terrno;
  }

  code = vnodeWriteCfg(pVnodeCfg);
  if (code != TSDB_CODE_SUCCESS) {
    vError("vgId:%d, failed to save vnode cfg, reason:%s", pVnodeCfg->cfg.vgId, tstrerror(code));
    return code;
  }

  // STsdbCfg tsdbCfg = {0};
  // tsdbCfg.tsdbId              = pVnodeCfg->cfg.vgId;
  // tsdbCfg.cacheBlockSize      = pVnodeCfg->cfg.cacheBlockSize;
  // tsdbCfg.totalBlocks         = pVnodeCfg->cfg.totalBlocks;
  // tsdbCfg.daysPerFile         = pVnodeCfg->cfg.daysPerFile;
  // tsdbCfg.keep                = pVnodeCfg->cfg.daysToKeep;
  // tsdbCfg.keep1               = pVnodeCfg->cfg.daysToKeep1;
  // tsdbCfg.keep2               = pVnodeCfg->cfg.daysToKeep2;
  // tsdbCfg.minRowsPerFileBlock = pVnodeCfg->cfg.minRowsPerFileBlock;
  // tsdbCfg.maxRowsPerFileBlock = pVnodeCfg->cfg.maxRowsPerFileBlock;
  // tsdbCfg.precision           = pVnodeCfg->cfg.precision;
  // tsdbCfg.compression         = pVnodeCfg->cfg.compression;
  // tsdbCfg.update              = pVnodeCfg->cfg.update;
  // tsdbCfg.cacheLastRow        = pVnodeCfg->cfg.cacheLastRow;

  // char tsdbDir[TSDB_FILENAME_LEN] = {0};
  // sprintf(tsdbDir, "vnode/vnode%d/tsdb", pVnodeCfg->cfg.vgId);
  if (tsdbCreateRepo(pVnodeCfg->cfg.vgId) < 0) {
    vError("vgId:%d, failed to create tsdb in vnode, reason:%s", pVnodeCfg->cfg.vgId, tstrerror(terrno));
    return TSDB_CODE_VND_INIT_FAILED;
  }

  vInfo("vgId:%d, vnode dir is created, walLevel:%d fsyncPeriod:%d", pVnodeCfg->cfg.vgId, pVnodeCfg->cfg.walLevel,
        pVnodeCfg->cfg.fsyncPeriod);
  code = vnodeOpen(pVnodeCfg->cfg.vgId);

  return code;
}

int32_t vnodeSync(int32_t vgId) {
  SVnodeObj *pVnode = vnodeAcquire(vgId);
  if (pVnode == NULL) {
    vDebug("vgId:%d, failed to sync, vnode not find", vgId);
    return TSDB_CODE_VND_INVALID_VGROUP_ID;
  }

  if (pVnode->role == TAOS_SYNC_ROLE_SLAVE) {
    vInfo("vgId:%d, vnode will sync, refCount:%d pVnode:%p", pVnode->vgId, pVnode->refCount, pVnode);

    pVnode->version = 0;
    pVnode->fversion = 0;
    walResetVersion(pVnode->wal, pVnode->fversion);

    syncRecover(pVnode->sync);
  }

  vnodeRelease(pVnode);

  return TSDB_CODE_SUCCESS;
}

int32_t vnodeDrop(int32_t vgId) {
  SVnodeObj *pVnode = vnodeAcquire(vgId);
  if (pVnode == NULL) {
    vDebug("vgId:%d, failed to drop, vnode not find", vgId);
    return TSDB_CODE_VND_INVALID_VGROUP_ID;
  }
  if (pVnode->dropped) {
    vnodeRelease(pVnode);
    return TSDB_CODE_SUCCESS;
  }

  vInfo("vgId:%d, vnode will be dropped, refCount:%d pVnode:%p", pVnode->vgId, pVnode->refCount, pVnode);
  pVnode->dropped = 1;

  vnodeRelease(pVnode);
  vnodeCleanupInMWorker(pVnode);

  return TSDB_CODE_SUCCESS;
}

static int32_t vnodeAlterImp(SVnodeObj *pVnode, SCreateVnodeMsg *pVnodeCfg) {
  STsdbCfg tsdbCfg = pVnode->tsdbCfg;
  SSyncCfg syncCfg = pVnode->syncCfg;
  int32_t  dbCfgVersion = pVnode->dbCfgVersion;
  int32_t  vgCfgVersion = pVnode->vgCfgVersion;

  int32_t code = vnodeWriteCfg(pVnodeCfg);
  if (code != TSDB_CODE_SUCCESS) {
    pVnode->dbCfgVersion = dbCfgVersion;
    pVnode->vgCfgVersion = vgCfgVersion;
    pVnode->syncCfg = syncCfg;
    pVnode->tsdbCfg = tsdbCfg;
    return code;
  }

  code = vnodeReadCfg(pVnode);
  if (code != TSDB_CODE_SUCCESS) {
    pVnode->dbCfgVersion = dbCfgVersion;
    pVnode->vgCfgVersion = vgCfgVersion;
    pVnode->syncCfg = syncCfg;
    pVnode->tsdbCfg = tsdbCfg;
    return code;
  }

  code = walAlter(pVnode->wal, &pVnode->walCfg);
  if (code != TSDB_CODE_SUCCESS) {
    pVnode->dbCfgVersion = dbCfgVersion;
    pVnode->vgCfgVersion = vgCfgVersion;
    pVnode->syncCfg = syncCfg;
    pVnode->tsdbCfg = tsdbCfg;
    return code;
  }

  bool tsdbCfgChanged = (memcmp(&tsdbCfg, &pVnode->tsdbCfg, sizeof(STsdbCfg)) != 0);
  bool syncCfgChanged = (memcmp(&syncCfg, &pVnode->syncCfg, sizeof(SSyncCfg)) != 0);

  vDebug("vgId:%d, tsdbchanged:%d syncchanged:%d while alter vnode", pVnode->vgId, tsdbCfgChanged, syncCfgChanged);

  if (tsdbCfgChanged || syncCfgChanged) {
    // vnode in non-ready state and still needs to return success instead of TSDB_CODE_VND_INVALID_STATUS
    // dbCfgVersion can be corrected by status msg
    if (syncCfgChanged) {
      if (!vnodeSetUpdatingStatus(pVnode)) {
        vDebug("vgId:%d, vnode is not ready, do alter operation later", pVnode->vgId);
        pVnode->dbCfgVersion = dbCfgVersion;
        pVnode->vgCfgVersion = vgCfgVersion;
        pVnode->syncCfg = syncCfg;
        pVnode->tsdbCfg = tsdbCfg;
        return TSDB_CODE_SUCCESS;
      }

      code = syncReconfig(pVnode->sync, &pVnode->syncCfg);
      if (code != TSDB_CODE_SUCCESS) {
        pVnode->dbCfgVersion = dbCfgVersion;
        pVnode->vgCfgVersion = vgCfgVersion;
        pVnode->syncCfg = syncCfg;
        pVnode->tsdbCfg = tsdbCfg;
        vnodeSetReadyStatus(pVnode);
        return code;
      }
    }

    if (tsdbCfgChanged && pVnode->tsdb) {
      code = tsdbConfigRepo(pVnode->tsdb, &pVnode->tsdbCfg);
      if (code != TSDB_CODE_SUCCESS) {
        pVnode->dbCfgVersion = dbCfgVersion;
        pVnode->vgCfgVersion = vgCfgVersion;
        pVnode->syncCfg = syncCfg;
        pVnode->tsdbCfg = tsdbCfg;
        vnodeSetReadyStatus(pVnode);
        return code;
      }
    }

    vnodeSetReadyStatus(pVnode);
  }

  return 0;
}

int32_t vnodeAlter(void *vparam, SCreateVnodeMsg *pVnodeCfg) {
  SVnodeObj *pVnode = vparam;

  vDebug("vgId:%d, current dbCfgVersion:%d vgCfgVersion:%d, input dbCfgVersion:%d vgCfgVersion:%d", pVnode->vgId,
         pVnode->dbCfgVersion, pVnode->vgCfgVersion, pVnodeCfg->cfg.dbCfgVersion, pVnodeCfg->cfg.vgCfgVersion);

  if (pVnode->dbCfgVersion == pVnodeCfg->cfg.dbCfgVersion && pVnode->vgCfgVersion == pVnodeCfg->cfg.vgCfgVersion) {
    vDebug("vgId:%d, cfg not change", pVnode->vgId);
    return TSDB_CODE_SUCCESS;
  }

  int32_t code = vnodeAlterImp(pVnode, pVnodeCfg);

  if (code != 0) {
    vError("vgId:%d, failed to alter vnode, code:0x%x", pVnode->vgId, code);
  } else {
    vDebug("vgId:%d, vnode is altered", pVnode->vgId);
  }

  return code;
}

static void vnodeFindWalRootDir(int32_t vgId, char *walRootDir) {
  char vnodeDir[TSDB_FILENAME_LEN] = "\0";
  snprintf(vnodeDir, TSDB_FILENAME_LEN, "/vnode/vnode%d/wal", vgId);

  TDIR *tdir = tfsOpendir(vnodeDir);
  if (!tdir) return;

  const TFILE *tfile = tfsReaddir(tdir);
  if (!tfile) {
    tfsClosedir(tdir);
    return;
  }

  sprintf(walRootDir, "%s/vnode/vnode%d", TFS_DISK_PATH(tfile->level, tfile->id), vgId);

  tfsClosedir(tdir);
}

int32_t vnodeOpen(int32_t vgId) {
  char temp[TSDB_FILENAME_LEN * 3];
  char rootDir[TSDB_FILENAME_LEN * 2];
  char walRootDir[TSDB_FILENAME_LEN * 2] = {0};
  snprintf(rootDir, TSDB_FILENAME_LEN * 2, "%s/vnode%d", tsVnodeDir, vgId);

  SVnodeObj *pVnode = calloc(sizeof(SVnodeObj), 1);
  if (pVnode == NULL) {
    vError("vgId:%d, failed to open vnode since no enough memory", vgId);
    return TAOS_SYSTEM_ERROR(errno);
  }

  atomic_add_fetch_32(&pVnode->refCount, 1);

  pVnode->vgId     = vgId;
  pVnode->fversion = 0;
  pVnode->version  = 0;  
  pVnode->tsdbCfg.tsdbId = pVnode->vgId;
  pVnode->rootDir = strdup(rootDir);
  pVnode->accessState = TSDB_VN_ALL_ACCCESS;
  tsem_init(&pVnode->sem, 0, 0);
  pthread_mutex_init(&pVnode->statusMutex, NULL);
  vnodeSetInitStatus(pVnode);

  tsdbIncCommitRef(pVnode->vgId);

  int32_t code = vnodeReadCfg(pVnode);
  if (code != TSDB_CODE_SUCCESS) {
    vError("vgId:%d, failed to read config file, set cfgVersion to 0", pVnode->vgId);
    vnodeCleanUp(pVnode);
    return 0;
  } 

  code = vnodeReadVersion(pVnode);
  if (code != TSDB_CODE_SUCCESS) {
    pVnode->version = 0;
    vError("vgId:%d, failed to read file version, generate it from data file", pVnode->vgId);
    // Allow vnode start even when read file version fails, set file version as wal version or zero
    // vnodeCleanUp(pVnode);
    // return code;
  }

  pVnode->fversion = pVnode->version;
  
  pVnode->wqueue = dnodeAllocVWriteQueue(pVnode);
  pVnode->qqueue = dnodeAllocVQueryQueue(pVnode);
  pVnode->fqueue = dnodeAllocVFetchQueue(pVnode);
  if (pVnode->wqueue == NULL || pVnode->qqueue == NULL || pVnode->fqueue == NULL) {
    vnodeCleanUp(pVnode);
    return terrno;
  }

  if (tsEnableStream) {
    SCqCfg cqCfg = {0};
    sprintf(cqCfg.user, "_root");
    strcpy(cqCfg.pass, tsInternalPass);
    strcpy(cqCfg.db, pVnode->db);
    cqCfg.vgId = vgId;
    cqCfg.cqWrite = vnodeWriteToCache;
    pVnode->cq = cqOpen(pVnode, &cqCfg);
    if (pVnode->cq == NULL) {
      vnodeCleanUp(pVnode);
      return terrno;
    }
  }

  STsdbAppH appH = {0};
  appH.appH = (void *)pVnode;
  appH.notifyStatus = vnodeProcessTsdbStatus;
  appH.cqH = pVnode->cq;
  appH.cqCreateFunc = cqCreate;
  appH.cqDropFunc = cqDrop;

  terrno = 0;
  pVnode->tsdb = tsdbOpenRepo(&(pVnode->tsdbCfg), &appH);
  if (pVnode->tsdb == NULL) {
    vnodeCleanUp(pVnode);
    return terrno;
  } else if (tsdbGetState(pVnode->tsdb) != TSDB_STATE_OK) {
    vError("vgId:%d, failed to open tsdb(state: %d), replica:%d reason:%s", pVnode->vgId,
           tsdbGetState(pVnode->tsdb), pVnode->syncCfg.replica, tstrerror(terrno));
    if (pVnode->syncCfg.replica <= 1) {
      vnodeCleanUp(pVnode);
      return TSDB_CODE_VND_INVALID_TSDB_STATE;
    } else {
      pVnode->fversion = 0;
      pVnode->version = 0;
    }
  }

  // walRootDir for wal & syncInfo.path (not empty dir of /vnode/vnode{pVnode->vgId}/wal)
  vnodeFindWalRootDir(pVnode->vgId, walRootDir);
  if (walRootDir[0] == 0) {
    int level = -1, id = -1;

    tfsAllocDisk(TFS_PRIMARY_LEVEL, &level, &id);
    if (level < 0 || id < 0) {
      vnodeCleanUp(pVnode);
      return terrno;
    }

    sprintf(walRootDir, "%s/vnode/vnode%d", TFS_DISK_PATH(level, id), vgId);
  }

  sprintf(temp, "%s/wal", walRootDir);
  pVnode->walCfg.vgId = pVnode->vgId;
  pVnode->wal = walOpen(temp, &pVnode->walCfg);
  if (pVnode->wal == NULL) { 
    vnodeCleanUp(pVnode);
    return terrno;
  }

  walRestore(pVnode->wal, pVnode, vnodeProcessWrite);
  if (pVnode->version == 0) {
    pVnode->fversion = 0;
    pVnode->version = walGetVersion(pVnode->wal);
  }

  code = tsdbSyncCommit(pVnode->tsdb);
  if (code != 0) {
    vError("vgId:%d, failed to commit after restore from wal since %s", pVnode->vgId, tstrerror(code));
    vnodeCleanUp(pVnode);
    return code;
  }

  walRemoveAllOldFiles(pVnode->wal);
  walRenew(pVnode->wal);

  pVnode->qMgmt = qOpenQueryMgmt(pVnode->vgId);
  if (pVnode->qMgmt == NULL) {
    vnodeCleanUp(pVnode);
    return terrno;
  }

  pVnode->events = NULL;

  vDebug("vgId:%d, vnode is opened in %s - %s, pVnode:%p", pVnode->vgId, rootDir, walRootDir, pVnode);

  vnodeAddIntoHash(pVnode);
  
  SSyncInfo syncInfo;
  syncInfo.vgId = pVnode->vgId;
  syncInfo.version = pVnode->version;
  syncInfo.syncCfg = pVnode->syncCfg;
  tstrncpy(syncInfo.path, walRootDir, TSDB_FILENAME_LEN);
  syncInfo.getWalInfoFp = vnodeGetWalInfo;
  syncInfo.writeToCacheFp = vnodeWriteToCache;
  syncInfo.confirmForward = vnodeConfirmForard; 
  syncInfo.notifyRoleFp = vnodeNotifyRole;
  syncInfo.notifyFlowCtrlFp = vnodeCtrlFlow;
  syncInfo.startSyncFileFp = vnodeStartSyncFile;
  syncInfo.stopSyncFileFp = vnodeStopSyncFile;
  syncInfo.getVersionFp = vnodeGetVersion;
  syncInfo.sendFileFp = tsdbSyncSend;
  syncInfo.recvFileFp = tsdbSyncRecv;
  syncInfo.pTsdb = pVnode->tsdb;
  pVnode->sync = syncStart(&syncInfo);

  if (pVnode->sync <= 0) {
    vError("vgId:%d, failed to open sync, replica:%d reason:%s", pVnode->vgId, pVnode->syncCfg.replica,
           tstrerror(terrno));
    vnodeRemoveFromHash(pVnode);
    vnodeCleanUp(pVnode);
    return terrno;
  }

  vnodeSetReadyStatus(pVnode);
  return TSDB_CODE_SUCCESS;
}

int32_t vnodeClose(int32_t vgId) {
  SVnodeObj *pVnode = vnodeAcquire(vgId);
  if (pVnode == NULL) return 0;
  if (pVnode->dropped) {
    vnodeRelease(pVnode);
    return 0;
  }

  vDebug("vgId:%d, vnode will be closed, pVnode:%p", pVnode->vgId, pVnode);
  vnodeRemoveFromHash(pVnode);
  vnodeRelease(pVnode);
  vnodeCleanUp(pVnode);

  return 0;
}

void vnodeDestroy(SVnodeObj *pVnode) {
  int32_t code = 0;
  int32_t vgId = pVnode->vgId;
  
  if (pVnode->qMgmt) {
    qCleanupQueryMgmt(pVnode->qMgmt);
    pVnode->qMgmt = NULL;
  }

  if (pVnode->wal) {
    walStop(pVnode->wal);
  }

  if (pVnode->tsdb) {
    // the deleted vnode does not need to commit, so as to speed up the deletion
    int toCommit = 1;
    if (pVnode->dropped) toCommit = 0;

    code = tsdbCloseRepo(pVnode->tsdb, toCommit);
    pVnode->tsdb = NULL;
  }

  // stop continuous query
  if (pVnode->cq) {
    void *cq = pVnode->cq;
    pVnode->cq = NULL;
    cqClose(cq);
  }

  if (pVnode->wal) {
    if (code != 0) {
      vError("vgId:%d, failed to commit while close tsdb repo, keep wal", pVnode->vgId);
    } else {
      walRemoveAllOldFiles(pVnode->wal);
    }
    walClose(pVnode->wal);
    pVnode->wal = NULL;
  }

  if (pVnode->wqueue) {
    dnodeFreeVWriteQueue(pVnode->wqueue);
    pVnode->wqueue = NULL;
  }

  if (pVnode->qqueue) {
    dnodeFreeVQueryQueue(pVnode->qqueue);
    pVnode->qqueue = NULL;
  }

  if (pVnode->fqueue) {
    dnodeFreeVFetchQueue(pVnode->fqueue);
    pVnode->fqueue = NULL;
  }

  tfree(pVnode->rootDir);

  if (pVnode->dropped) {
    char rootDir[TSDB_FILENAME_LEN] = {0};    
    char stagingDir[TSDB_FILENAME_LEN] = {0};
    sprintf(rootDir, "%s/vnode%d", "vnode", vgId);
    sprintf(stagingDir, "%s/.staging/vnode%d", "vnode_bak", vgId);

    tfsRename(rootDir, stagingDir);

    vnodeBackup(vgId);

    dnodeSendStatusMsgToMnode();
  }

  tsem_destroy(&pVnode->sem);
  pthread_mutex_destroy(&pVnode->statusMutex);
  free(pVnode);
  tsdbDecCommitRef(vgId);
}

void vnodeCleanUp(SVnodeObj *pVnode) {
  vDebug("vgId:%d, vnode will cleanup, refCount:%d pVnode:%p", pVnode->vgId, pVnode->refCount, pVnode);

  vnodeSetClosingStatus(pVnode);

  vnodeRemoveFromHash(pVnode);

  // stop replication module
  if (pVnode->sync > 0) {
    int64_t sync = pVnode->sync;
    pVnode->sync = -1;
    syncStop(sync);
  }

  vDebug("vgId:%d, vnode is cleaned, refCount:%d pVnode:%p", pVnode->vgId, pVnode->refCount, pVnode);
  vnodeRelease(pVnode);
}

static int32_t vnodeProcessTsdbStatus(void *arg, int32_t status, int32_t eno) {
  SVnodeObj *pVnode = arg;

  if (eno != TSDB_CODE_SUCCESS) {
    vError("vgId:%d, failed to commit since %s, fver:%" PRIu64 " vver:%" PRIu64, pVnode->vgId, tstrerror(eno),
           pVnode->fversion, pVnode->version);
    pVnode->isCommiting = 0;
    pVnode->isFull = 1;
    return 0;
  }

  if (status == TSDB_STATUS_COMMIT_START) {
    pVnode->isCommiting = 1;
    pVnode->cversion = pVnode->version;
    vInfo("vgId:%d, start commit, fver:%" PRIu64 " vver:%" PRIu64, pVnode->vgId, pVnode->fversion, pVnode->version);
    if (!vnodeInInitStatus(pVnode)) {
      return walRenew(pVnode->wal);
    }
    return 0;
  }

  if (status == TSDB_STATUS_COMMIT_OVER) {
    pVnode->isCommiting = 0;
    pVnode->isFull = 0;
    pVnode->fversion = pVnode->cversion;
    vInfo("vgId:%d, commit over, fver:%" PRIu64 " vver:%" PRIu64, pVnode->vgId, pVnode->fversion, pVnode->version);
    if (!vnodeInInitStatus(pVnode)) {
      walRemoveOneOldFile(pVnode->wal);
    }
    return vnodeSaveVersion(pVnode);
  }

  return 0;
}
