/* Copyright (C) 2014 InfiniDB, Inc.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; version 2 of
   the License.

   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.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

//  $Id: we_chunkmanager.h 4726 2013-08-07 03:38:36Z bwilkinson $

/** @file */

#pragma once

#include <cstdio>
#include <map>
#include <list>
#include <string>
#include <boost/scoped_array.hpp>

#include "we_type.h"
#include "we_typeext.h"
#include "we_define.h"
#include "idbcompress.h"
#include "IDBFileSystem.h"

#define EXPORT

//#define IDB_COMP_DEBUG
#ifdef IDB_COMP_DEBUG
#define WE_COMP_DBG(x) \
  {                    \
    x                  \
  }
#else
#define WE_COMP_DBG(x) \
  {                    \
  }
#endif

namespace logging
{
// use Logger (not we_log) for now.
class Logger;
}  // namespace logging

namespace WriteEngine
{
// forward reference
class FileOp;

const int UNCOMPRESSED_CHUNK_SIZE = compress::CompressInterface::UNCOMPRESSED_INBUF_LEN;
const int COMPRESSED_FILE_HEADER_UNIT = compress::CompressInterface::HDR_BUF_LEN;

// assume UNCOMPRESSED_CHUNK_SIZE > 0xBFFF (49151), 8 * 1024 bytes padding

const int BLOCKS_IN_CHUNK = UNCOMPRESSED_CHUNK_SIZE / BYTE_PER_BLOCK;
const int MAXOFFSET_PER_CHUNK = 511 * BYTE_PER_BLOCK;

// chunk information
typedef int64_t ChunkId;
struct ChunkData
{
  ChunkId fChunkId;
  unsigned int fLenUnCompressed;
  char fBufUnCompressed[UNCOMPRESSED_CHUNK_SIZE];
  bool fWriteToFile;

  ChunkData(ChunkId id = 0) : fChunkId(id), fLenUnCompressed(0), fWriteToFile(false)
  {
  }
  bool operator<(const ChunkData& rhs) const
  {
    return fChunkId < rhs.fChunkId;
  }
};

// compressed DB file header information
struct CompFileHeader
{
  char fHeaderData[COMPRESSED_FILE_HEADER_UNIT * 2];
  char* fControlData;
  char* fPtrSection;
  boost::scoped_array<char> fLongPtrSectData;

  CompFileHeader() : fControlData(fHeaderData), fPtrSection(fHeaderData + COMPRESSED_FILE_HEADER_UNIT)
  {
  }
};

// unique ID of a DB file
struct FileID
{
  FID fFid;
  uint32_t fDbRoot;
  uint32_t fPartition;
  uint32_t fSegment;

  FileID(FID f, uint32_t r, uint32_t p, uint32_t s) : fFid(f), fDbRoot(r), fPartition(p), fSegment(s)
  {
  }

  bool operator<(const FileID& rhs) const
  {
    return ((fFid < rhs.fFid) || (fFid == rhs.fFid && fDbRoot < rhs.fDbRoot) ||
            (fFid == rhs.fFid && fDbRoot == rhs.fDbRoot && fPartition < rhs.fPartition) ||
            (fFid == rhs.fFid && fDbRoot == rhs.fDbRoot && fPartition == rhs.fPartition &&
             fSegment < rhs.fSegment));
  }

  bool operator==(const FileID& rhs) const
  {
    return (fFid == rhs.fFid && fDbRoot == rhs.fDbRoot && fPartition == rhs.fPartition &&
            fSegment == rhs.fSegment);
  }
};

// compressed DB file information
class CompFileData
{
 public:
  CompFileData(const FileID& id, const FID& fid,
               const execplan::CalpontSystemCatalog::ColDataType colDataType, int colWidth,
               bool readOnly = false)
   : fFileID(id)
   , fFid(fid)
   , fColDataType(colDataType)
   , fColWidth(colWidth)
   , fDctnryCol(false)
   , fFilePtr(NULL)
   , fCompressionType(1)
   , fReadOnly(readOnly)
  {
  }

  ChunkData* findChunk(int64_t cid) const;

 protected:
  FileID fFileID;
  FID fFid;
  execplan::CalpontSystemCatalog::ColDataType fColDataType;
  int fColWidth;
  bool fDctnryCol;
  IDBDataFile* fFilePtr;
  std::string fFileName;
  CompFileHeader fFileHeader;
  std::list<ChunkData*> fChunkList;
  uint32_t fCompressionType;
  bool fReadOnly;

  friend class ChunkManager;
};

class ChunkManager
{
 public:
  // @brief constructor
  EXPORT ChunkManager();

  // @brief destructor
  EXPORT virtual ~ChunkManager();

  // @brief Retrieve a file pointer in the chunk manager.
  //        for column file
  IDBDataFile* getFilePtr(const Column& column, uint16_t root, uint32_t partition, uint16_t segment,
                          std::string& filename, const char* mode, int size, bool useTmpSuffix,
                          bool isReadOnly = false) const;

  // @brief Retrieve a file pointer in the chunk manager.
  //        for dictionary file
  IDBDataFile* getFilePtr(const FID& fid, uint16_t root, uint32_t partition, uint16_t segment,
                          std::string& filename, const char* mode, int size, bool useTmpSuffix) const;

  // @brief Retrieve a file pointer in the chunk manager by the given `filename`.
  //        for column/dict segment file
  IDBDataFile* getFilePtrByName(const std::string& filename, FID& fid, uint16_t root, uint32_t partition,
                                uint16_t segment, execplan::CalpontSystemCatalog::ColDataType colDataType,
                                uint32_t colWidth, const char* mode, int32_t size, bool useTmpSuffix,
                                bool isDict) const;

  // @brief Create a compressed dictionary file with an appropriate header.
  IDBDataFile* createDctnryFile(const FID& fid, int64_t width, uint16_t root, uint32_t partition,
                                uint16_t segment, const char* filename, const char* mode, int size,
                                int64_t lbid);

  // @brief Read a block from pFile at offset fbo.
  //        The data may copied from memory if the chunk it belongs to is already available.
  int readBlock(IDBDataFile* pFile, unsigned char* readBuf, uint64_t fbo);

  // @brief Save a block to a chunk in pFile.
  //        The block is not written to disk immediately, will be delayed until flush.
  int saveBlock(IDBDataFile* pFile, const unsigned char* writeBuf, uint64_t fbo);

  // @brief Write all active chunks to disk, and reset all repository.
  EXPORT int flushChunks(int rc, const std::map<FID, FID>& columOids);

  // @brief Reset all repository without writing anything to disk.
  void cleanUp(const std::map<FID, FID>& columOids);

  // @brief Expand an initial column, not dictionary, extent to a full extent.
  int expandAbbrevColumnExtent(IDBDataFile* pFile, const uint8_t* emptyVal, int width);

  // @brief Update column extent
  int updateColumnExtent(IDBDataFile* pFile, int addBlockCount, int64_t lbid);

  // @brief Update dictionary extent
  int updateDctnryExtent(IDBDataFile* pFile, int addBlockCount, int64_t lbid);

  // @brief Read in n continuous blocks to read buffer.
  //        for backing up blocks to version buffer
  int readBlocks(IDBDataFile* pFile, unsigned char* readBuf, uint64_t fbo, size_t n);

  // @brief Restore the data block at offset fbo from version buffer
  //        for rollback
  int restoreBlock(IDBDataFile* pFile, const unsigned char* writeBuf, uint64_t fbo);

  // @brief Retrieve the total block count of a DB file.
  int getBlockCount(IDBDataFile* pFile);

  // @brief Set FileOp pointer (for compression type, empty value, txnId, etc.)
  void fileOp(FileOp* fileOp);

  // @brief Control the number of active chunks being stored in memory
  void setMaxActiveChunkNum(unsigned int maxActiveChunkNum)
  {
    fMaxActiveChunkNum = maxActiveChunkNum;
  }

  // @brief Use this flag to avoid logging and backing up chunks, tmp files.
  void setBulkFlag(bool isBulkLoad)
  {
    fIsBulkLoad = isBulkLoad;
  }

  // @brief Use this flag to flush chunk when is full.
  void setIsInsert(bool isInsert)
  {
    fIsInsert = isInsert;
  }
  bool getIsInsert()
  {
    return fIsInsert;
  }

  void setTransId(const TxnID& transId)
  {
    fTransId = transId;
  }

  // @brief bug5504, Use non transactional DML for InfiniDB with HDFS
  EXPORT int startTransaction(const TxnID& transId) const;
  EXPORT int confirmTransaction(const TxnID& transId) const;
  EXPORT int endTransaction(const TxnID& transId, bool success) const;
  // @brief Use this flag to fix bad chunk.
  void setFixFlag(bool isFix)
  {
    fIsFix = isFix;
  }

  EXPORT int checkFixLastDictChunk(const FID& fid, uint16_t root, uint32_t partition, uint16_t segment);

 protected:
  // @brief Retrieve pointer to a compressed DB file.
  CompFileData* getFileData(const FID& fid, uint16_t root, uint32_t partition, uint16_t segment,
                            std::string& filename, const char* mode, int size,
                            const execplan::CalpontSystemCatalog::ColDataType colDataType, int colWidth,
                            bool useTmpSuffix, bool dictnry = false, bool isReadOnly = false) const;

  CompFileData* getFileDataByName(const std::string& filename, const FID& fid, uint16_t root,
                                  uint32_t partition, uint16_t segment, const char* mode, int size,
                                  const execplan::CalpontSystemCatalog::ColDataType colDataType, int colWidth,
                                  bool useTmpSuffix, bool dctnry) const;

  // @brief Retrieve a chunk of pFile from disk.
  int fetchChunkFromFile(IDBDataFile* pFile, int64_t id, ChunkData*& chunkData);

  // @brief Compress a chunk and write it to file.
  int writeChunkToFile(CompFileData* fileData, int64_t id);
  int writeChunkToFile(CompFileData* fileData, ChunkData* chunkData);

  // @brief Write the compressed data to file and log a recover entry.
  int writeCompressedChunk(CompFileData* fileData, int64_t offset, int64_t size);
  inline int writeCompressedChunk_(CompFileData* fileData, int64_t offset);

  // @brief Write the file header to disk.
  int writeHeader(CompFileData* fileData, int ln);
  inline int writeHeader_(CompFileData* fileData, int ptrSecSize);

  // @brief open a compressed DB file.
  int openFile(CompFileData* fileData, const char* mode, int colWidth, bool useTmpSuffix, int ln) const;

  // @brief set offset in a compressed DB file from beginning.
  int setFileOffset(IDBDataFile* pFile, const std::string& fileName, off64_t offset, int ln) const;

  // @brief read from a compressed DB file.
  int readFile(IDBDataFile* pFile, const std::string& fileName, void* buf, size_t size, int ln) const;

  // @brief write to a compressed DB file.
  int writeFile(IDBDataFile* pFile, const std::string& fileName, void* buf, size_t size, int ln) const;

  // @brief Close a compressed DB file.
  int closeFile(CompFileData* fileData);

  // @brief Set empty values to a chunk.
  void initializeColumnChunk(char* buf, CompFileData* fileData);
  void initializeDctnryChunk(char* buf, int size);

  // @brief Calculate the header size based on column width.
  int calculateHeaderSize(int width);

  // @brief Moving chunks as a result of expanding a chunk.
  int reallocateChunks(CompFileData* fileData);

  // @brief verify chunks in the file are OK
  int verifyChunksAfterRealloc(CompFileData* fileData);

  // @brief log a message to the syslog
  void logMessage(int code, int level, int lineNum, int fromLine = -1) const;
  void logMessage(const std::string& msg, int level) const;

  // @brief Write a DML recovery log
  int writeLog(TxnID txnId, std::string backUpFileType, std::string filename, std::string& aDMLLogFileName,
               int64_t size = 0, int64_t offset = 0) const;

  // @brief remove DML recovery logs
  int removeBackups(TxnID txnId);

  // @brief swap the src file to dest file
  int swapTmpFile(const std::string& src, const std::string& dest);

  // @brief construnct a DML log file name
  int getDMLLogFileName(std::string& aDMLLogFileName, const TxnID& txnId) const;

  mutable std::map<FileID, CompFileData*> fFileMap;
  mutable std::map<IDBDataFile*, CompFileData*> fFilePtrMap;
  std::list<std::pair<FileID, ChunkData*> > fActiveChunks;
  unsigned int fMaxActiveChunkNum;  // max active chunks per file
  char* fBufCompressed;
  size_t fLenCompressed;
  size_t fMaxCompressedBufSize;
  size_t fUserPaddings;
  bool fIsBulkLoad;
  bool fDropFdCache;
  bool fIsInsert;
  bool fIsHdfs;
  FileOp* fFileOp;
  compress::CompressorPool fCompressorPool;
  logging::Logger* fSysLogger;
  TxnID fTransId;
  int fLocalModuleId;
  idbdatafile::IDBFileSystem& fFs;
  bool fIsFix;
  size_t COMPRESSED_CHUNK_SIZE;

 private:
  CompFileData* getFileData_(const FileID& fid, const std::string& filename, const char* mode, int size,
                             const execplan::CalpontSystemCatalog::ColDataType colDataType, int colWidth,
                             bool useTmpSuffix, bool dictnry = false, bool isReadOnly = false) const;
};

}  // namespace WriteEngine

#undef EXPORT