// ----------------------------------------------------------------------
// File: ComputeBlockXS.cc
// Author: Andreas-Joachim Peters - CERN
// ----------------------------------------------------------------------

/************************************************************************
 * EOS - the CERN Disk Storage System                                   *
 * Copyright (C) 2011 CERN/Switzerland                                  *
 *                                                                      *
 * 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, either version 3 of the License, or    *
 * (at your option) any later version.                                  *
 *                                                                      *
 * 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, see <http://www.gnu.org/licenses/>.*
 ************************************************************************/

#include "fst/checksum/ChecksumPlugins.hh"
#include "fst/io/FileIoPluginCommon.hh"
#include "common/LayoutId.hh"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>


int
main(int argc, const char* argv[])
{
  if (argc != 2) {
    fprintf(stderr, "usage: eos-check-blockxs <path> \n");
    exit(-1);
  }

  XrdOucString path = argv[1];
  XrdOucString pathXS = path;
  pathXS += ".xsmap";
  int fd = open(path.c_str(), O_RDONLY);

  if (fd < 0) {
    fprintf(stderr, "error: cannot open path %s\n", path.c_str());
    exit(-1);
  }

  int fdxs = open(pathXS.c_str(), O_RDONLY);

  if (fdxs < 0) {
    fprintf(stderr, "error: cannot open block checksum file for path %s\n",
            pathXS.c_str());
    exit(-1);
  }

  int ngood = 0;
  int nerr = 0;
  std::unique_ptr<eos::fst::FileIo> io(eos::fst::FileIoPluginHelper::GetIoObject(
                                         pathXS.c_str()));
  std::string checksumtype;
  std::string blocksize;

  if (io->attrGet("user.eos.blockchecksum", checksumtype) ||
      io->attrGet("user.eos.blocksize", blocksize)) {
    fprintf(stderr,
            "error: the extended attributes are missing on the block checksum file!\n");
    exit(-1);
  }

  XrdOucString envstring = "eos.layout.blockchecksum=";
  envstring += checksumtype.c_str();
  XrdOucEnv env(envstring.c_str());
  unsigned long checksumType = eos::common::LayoutId::GetBlockChecksumFromEnv(
                                 env);
  int blockSize = atoi(blocksize.c_str());
  int blockSizeSymbol = eos::common::LayoutId::BlockSizeEnum(blockSize);
  unsigned int layoutid =
    eos::common::LayoutId::GetId(eos::common::LayoutId::kPlain,
                                 eos::common::LayoutId::kNone, 0,
                                 blockSizeSymbol, checksumType);
  std::unique_ptr<eos::fst::CheckSum> checksum =
    eos::fst::ChecksumPlugins::GetChecksumObject(layoutid, true);

  if (!checksum) {
    fprintf(stderr, "error: failed to get checksum object for file %s",
            path.c_str());
    exit(-1);
  }

  struct stat info;

  if (fstat(fd, &info)) {
    fprintf(stderr, "error: failed to stat file %s\n", path.c_str());
    exit(-1);
  }

  off_t maxfilesize = info.st_size;
  off_t offset = 0;
  char* buffer = (char*) malloc(blockSize);

  if (!buffer) {
    fprintf(stderr, "error: cannot allocate blockmemory of size %u\n",
            (unsigned int) blockSize);
    exit(-1);
  }

  if (checksum->OpenMap(pathXS.c_str(), maxfilesize, blockSize, true)) {
    do {
      int nread = read(fd, buffer, blockSize);

      if (nread < 0) {
        fprintf(stderr, "error: failed to read block at offset %llu\n",
                (unsigned long long) offset);
        free(buffer);
        exit(-1);
      }

      if (nread < blockSize) {
        // 0 rest of the block
        memset(buffer + nread, 0, blockSize - nread);
      }

      checksum->Reset();

      if (!checksum->AddBlockSum(offset, buffer, blockSize)) {
        fprintf(stderr, "block-XS error => offset %llu\n", (unsigned long long) offset);
        nerr++;
      } else {
        // fprintf(stderr,"block-XS ok    => offset %llu\n", (unsigned long long)offset);
        ngood++;
      }

      if (nread < blockSize) {
        break;
      }

      offset += nread;
    } while (1);
  } else {
    fprintf(stderr, "error: unable to open block checksum map\n");
  }

  checksum->CloseMap();
  free(buffer);
  close(fd);
  close(fdxs);
  fprintf(stderr, "%s : tot: %i ok: %i error: %i\n", path.c_str(), ngood + nerr,
          ngood, nerr);

  if (nerr) {
    exit(-1);
  }

  exit(0);
}