/*
----
This file is part of SECONDO.

Copyright (C) 2015,
Faculty of Mathematics and Computer Science,
Database Systems for New Applications.

SECONDO 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 2 of the License, or
(at your option) any later version.

SECONDO 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 SECONDO; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
----


//[$][\$]

*/

#ifndef DIST2HELPER
#define DIST2HELPER


#include "SecondoSMI.h"
#include "SecondoInterfaceCS.h"
#include "frel.h"
#include "StringUtils.h"
#include "Algebras/Relation-C++/RelationAlgebra.h"

namespace distributed2{

/*

1.1 ~readVar~

Using this function, objects stored in a single block of memory
can be read from a SmiRecord.

*/

template<class T>
bool readVar(T& value, SmiRecord& record, size_t& offset){
  bool res = record.Read(&value, sizeof(T), offset) == sizeof(T);
  offset += sizeof(T);
  return res;
}


/*
1.2 ~readVar~

Using this variant of readVar, a string can be read from an
SmiRecord.

*/
template<>
bool readVar<std::string>(std::string& value, 
                          SmiRecord& record, size_t& offset);

/*
1.3 writeVar

This function writes an object cosisting of a single block of
memory into an SmiRecord.

*/

template<class T>
bool writeVar(const T& value, SmiRecord& record, size_t& offset){
  bool res = record.Write(&value, sizeof(T), offset) == sizeof(T);
  offset += sizeof(T);
  return res;
}

/*
1.4 writeVar

This variant of ~writeVar~ write a string into an SmiRecord.

*/

template<>
bool writeVar<std::string>(
  const std::string& value, SmiRecord& record, size_t& offset);

void showCommand(SecondoInterfaceCS* src,
                 const std::string& host,
                 const int port,
                 const std::string& cmd,
                 bool start,
                 bool showCommands);

/*
Some Helper functions.

*/

std::string getUDRelType(ListExpr r);

/*
1.0.1 ~rewriteQuery~

This function replaces occurences of [$]<Ident> within the string orig
by corresponding const expressions. If one Ident does not represent
a valid object name, the result will be false and the string is
unchanged.

*/

std::string rewriteRelType(ListExpr relType);

/*
The next function returns a constant expression for an
database object.

*/

bool getConstEx(const std::string& objName, std::string& result);


template<class T>
void print(std::vector<T>& v, std::ostream& out);



/*
rewrites a query. Replaces dollar signs by numbers.

*/
bool rewriteQuery(const std::string& orig, std::string& result);

/*
Function ~isWorkerRelDesc~

This function checks wether a relation is a valid description of
a set of workers. It returns true if it is so , false otherwise.
If the list is correct, the result parameter will be a list
with three arguments containing the postions of the attributes
~Host~, ~Port~, and ~Config~. In the false case, the errMsg
parameter will contain an error message.

*/

bool isWorkerRelDesc(ListExpr rel, ListExpr& positions, ListExpr& types,
                     std::string& errMsg);

}

#endif