//

#include <iostream>
#include <iomanip>
#include <getopt.h>
#include <errno.h>
#include <boost/thread.hpp>
#define NDEBUG
#include <cassert>
#include "writeengine.h"

using namespace std;

void timespec_sub(const struct timespec& tv1, const struct timespec& tv2, struct timespec& diff)
{
  if (tv2.tv_nsec < tv1.tv_nsec)
  {
    diff.tv_sec = tv2.tv_sec - tv1.tv_sec - 1;
    diff.tv_nsec = tv1.tv_nsec - tv2.tv_nsec;
  }
  else
  {
    diff.tv_sec = tv2.tv_sec - tv1.tv_sec;
    diff.tv_nsec = tv2.tv_nsec - tv1.tv_nsec;
  }
}

// TODO:
// add threads for reading a file
// add threads for reading multiple files

struct readThr
{
 public:
  readThr(const int oid, const int rSize)
  {
    fblockSize = 8192;
    fpageSize = getpagesize();
    freadBlocks = rSize;
    freadSize = rSize * fblockSize;  // read size ib bytes
    freadBufferSz = freadSize + fpageSize;
    falignedbuff = 0;
    foid = oid;
    facc = 0;
    memset(fname, 0, sizeof(fname));
    memset((char*)&ftm, 0, sizeof(ftm));
    memset((char*)&ftm2, 0, sizeof(ftm2));
    memset((char*)&ftm3, 0, sizeof(ftm3));
    memset((char*)&fstarttm, 0, sizeof(fstarttm));
    memset((char*)&fendtm, 0, sizeof(fendtm));
    memset((char*)&ftottm, 0, sizeof(ftottm));
    fodirect = true;
    fd = 0;
    cout << "o: " << foid << " r: " << freadBlocks << " b: " << freadBufferSz << endl;
  }

  void operator()()
  {
    WriteEngine::FileOp fFileOp;
    char frealbuff[freadBufferSz];
    memset(frealbuff, 0, freadBufferSz);

    if (frealbuff == 0)
    {
      cerr << "thr_popper: Can't allocate space for a whole extent in memory" << endl;
      return;
    }

    if (fFileOp.getFileName(foid, fname) != WriteEngine::NO_ERROR)
    {
      fname[0] = 0;
      throw std::runtime_error("fileOp.getFileName failed");
    }
    else
    {
      cout << "Reading oid: " << foid << " od: " << fodirect << " file: " << fname << endl;
    }

#if __LP64__
    falignedbuff = (char*)((((ptrdiff_t)frealbuff >> 12) << 12) + fpageSize);
#else
    falignedbuff = (char*)(((((ptrdiff_t)frealbuff >> 12) << 12) & 0xffffffff) + fpageSize);
#endif
    idbassert(((ptrdiff_t)falignedbuff - (ptrdiff_t)frealbuff) < (ptrdiff_t)fpageSize);
    idbassert(((ptrdiff_t)falignedbuff % fpageSize) == 0);

    if (fodirect)
      fd = open(fname, O_RDONLY | O_DIRECT | O_LARGEFILE | O_NOATIME);
    else
      fd = open(fname, O_RDONLY | O_LARGEFILE | O_NOATIME);

    if (fd < 0)
    {
      cerr << "Open failed" << endl;
      perror("open");
      throw runtime_error("Error opening file");
    }

    uint64_t i = 1;
    uint64_t rCnt = 0;

    clock_gettime(CLOCK_REALTIME, &fstarttm);

    while (i > 0)
    {
      clock_gettime(CLOCK_REALTIME, &ftm);
      i = pread(fd, falignedbuff, freadSize, facc);
      clock_gettime(CLOCK_REALTIME, &ftm2);

      idbassert(i == 0 || i == freadSize);
      idbassert(i % fpageSize == 0);
      idbassert(facc % fpageSize == 0);

      if (i < 0 && errno == EINTR)
      {
        timespec_sub(ftm, ftm2, ftm3);
        cout << "* " << i << " " << right << setw(2) << setfill(' ') << ftm3.tv_sec << "." << right << setw(9)
             << setfill('0') << ftm3.tv_nsec << endl;
        continue;
      }
      else if (i < 0)
      {
        timespec_sub(ftm, ftm2, ftm3);
        cout << "* i: " << i << " sz: " << freadSize << " acc: " << facc << right << setw(2) << setfill(' ')
             << ftm3.tv_sec << " " << right << ftm3.tv_nsec << endl;
        perror("pread");
      }

      facc += i;

      if (i > 0)
        rCnt++;

      /**
      timespec_sub(ftm, ftm2, ftm3);
      cout
          << rCnt << " " << facc/(1024*1024)
          << right << setw(2) << setfill(' ') << ftm3.tv_sec << "."
          << right << ftm3.tv_nsec << " i: " << i/(1024*1024)
          << endl;
      **/

    }  // while(acc...

    clock_gettime(CLOCK_REALTIME, &fendtm);
    timespec_sub(fstarttm, fendtm, ftottm);

    cout << "Total reads: " << rCnt << " sz: " << facc / (1024 * 1024) << "MB"
         << " tm: " << ftottm.tv_sec << "secs " << ftottm.tv_nsec << "ns" << endl;

    facc = 0;
    close(fd);
  }  // operator()

 public:
  uint64_t facc;
  uint64_t freadBlocks;  // read size ib blocks
  uint64_t freadSize;    // read size ib bytes
  uint64_t freadBufferSz;
  uint64_t fblockSize;
  char* falignedbuff;
  unsigned fpageSize;
  BRM::OID_t foid;
  char fname[256];
  struct timespec ftm;
  struct timespec ftm2;
  struct timespec ftm3;
  struct timespec fstarttm;
  struct timespec fendtm;
  struct timespec ftottm;
  bool fodirect;
  int fd;

};  // struct readThr

//
void usage()
{
  cerr << "usage: mtread -o <oid> -s <read size in blocks>" << endl;
}

// main()
//
int main(int argc, char** argv)
{
  int ch = 0;
  int readBlocks = 0;
  BRM::OID_t oid = 0;
  std::vector<BRM::OID_t> oidList;

  enum CLA_ENUM
  {
    OID = (int)0,
    READSIZE
  };

  // longopt struct
  // struct option {
  // const char *name;
  // int has_arg;
  // int *flag;
  // int val;
  //};

  static struct option long_options[] = {//{const char *name, 	int has_arg, 	int *flag,	int val},
                                         {"oid", required_argument, NULL, OID},
                                         {"rsize", required_argument, NULL, READSIZE},
                                         {0, 0, 0, 0}};

  if (argc <= 1)
  {
    return -1;
  }

  // process command line arguments
  while ((ch = getopt_long_only(argc, argv, "o:s:", long_options, NULL)) != -1)
  {
    // pid_t pidId = getpid();
    switch (ch)
    {
      case OID:
      case 'o':
        oid = atoi(optarg);
        oidList.push_back(oid);
        cout << "oid: " << optarg << endl;
        break;

      case READSIZE:
      case 's':
        readBlocks = atoi(optarg);
        cout << "read size: " << optarg << endl;

        if (readBlocks <= 0)
          readBlocks = 1;

        break;

      case '?':
      default:
        cout << "optarg " << optarg << endl;
        usage();
        break;

    }  // switch

  }  // while...

  uint32_t idx = 0;
  std::vector<boost::thread*> thrList;

  while (idx < oidList.size())
  {
    struct readThr rdr(oidList[idx++], readBlocks);
    boost::thread* thr = new boost::thread(rdr);
    thrList.push_back(thr);
  }

  idx = 0;

  while (idx < thrList.size())
  {
    boost::thread* thr = thrList[idx++];
    thr->join();
    delete thr;
  }

  thrList.clear();

}  // main