#include <string.h>

#include "BinaryLogReader.h"

std::istream &operator >>(std::istream &stream, Record::Ref &record)
{
  record = NULL;
  if (!stream)
    return stream;
  char envelope[8];
  stream.read(envelope, 8);
  if (!stream.gcount())
    // End of file (or other error) before we got started.  Return that
    // error exactly as is.
    return stream;
  if (stream.gcount() != 8)
  { // Error in the middle of the record.  Promote this to bad.  If we failed
    // in the middle of the record, we have no (automatic) way to resync and
    // find the next record.
    stream.setstate(std::ios::badbit);
    return stream;
  }
  if (memcmp(envelope, "HERE:", 5))
  { // The marker wasn't found.  That means we were not positioned at the 
    // beginning of a valid record.
    stream.setstate(std::ios::badbit);
    return stream;
  }
  int length = (unsigned char)envelope[5];
  length <<= 8;
  length |= (unsigned char)envelope[6];
  length <<= 8;
  length |= (unsigned char)envelope[7];
  std::string encoded(length, '\0');
  stream.read(&encoded[0], length);
  if (stream.gcount() != length)
  { // Error in the middle of the record.  Promote this to bad.
    stream.setstate(std::ios::badbit);
    return stream;
  }
  record = Record::create(encoded);
  if (!record)
    // Invalid record.  As far as we know the stream is okay, and you might
    // be able to read the next record.
    stream.setstate(std::ios::failbit);
  return stream;
}