#ifndef OBJECT_H
#define OBJECT_H
#include <errno.h>
#include <inttypes.h>
#include <stack>
#include <stdio.h>
#include <string.h>
#include "common.h"

// Bison location
struct grammatic_location
{
 struct incloc
 {
  int line,column;
  std::string filename;
 };
 int first_line;
 int first_column;
 int last_line;
 int last_column;
 std::list<struct incloc> incstack;
 std::string filename;
};

class StackElem
{
 StackElem()=delete;
 StackElem(const StackElem&)=delete;
public:
 enum Type {TYPE_EMPTY,TYPE_BEGINLIST,TYPE_ENDLIST,TYPE_MKPAIR,TYPE_OBJECT,TYPE_VARIABLE,TYPE_FUNCTION};
 StackElem(Type t, const struct grammatic_location& loc, const char* s=nullptr):type(t),obj(nullptr),location(loc)
 {
  if(TYPE_BEGINLIST==t || TYPE_ENDLIST==t) return;
  if( (TYPE_VARIABLE==t || TYPE_FUNCTION==t || TYPE_MKPAIR==t) && nullptr!=s) name=s;
  else type=TYPE_EMPTY;
 }
 StackElem(Type t, const struct grammatic_location& loc, const std::string& s):type(t),obj(nullptr),location(loc)
 {
  if(TYPE_VARIABLE==t || TYPE_FUNCTION==t || TYPE_MKPAIR==t) name=s;
  else type=TYPE_EMPTY;
 }
 StackElem(ObjectBase* o, const struct grammatic_location& loc):type(TYPE_OBJECT),obj(o),location(loc) {}
 ~StackElem() {if(TYPE_OBJECT==type) delete obj;}
 StackElem(StackElem&& s):type(s.type),name(s.name),location(s.location)
 {
  if(TYPE_OBJECT==type)
  {
   // Simple copy of pointer
   obj=s.obj;
   // Prevent destruction of ObjectBase in StackElem destructor
   s.type=TYPE_EMPTY;
  }
 }

 const ObjectBase* Object() const {return isObject()?obj:nullptr;}
 // Detach object
 ObjectBase* PickObject()
 {
  if(isObject())
  {
   type=TYPE_EMPTY;
   return obj;
  }
  else return nullptr;
 }
 bool ReplaceByObject(ObjectBase* ob)
 {
  if(isObject()) {delete ob; return false;}
  type=TYPE_OBJECT;
  obj=ob;
  return true;
 }
 std::string Name() const {return (isVar() || isFunc() || isMKPair())?name:std::string();}
 bool isObject() const {return (TYPE_OBJECT==type);}
 bool isVar() const {return (TYPE_VARIABLE==type);}
 bool isFunc() const {return (TYPE_FUNCTION==type);}
 bool isBList() const {return (TYPE_BEGINLIST==type);}
 bool isEList() const {return (TYPE_ENDLIST==type);}
 bool isMKPair() const {return (TYPE_MKPAIR==type);}
 const struct grammatic_location& Location() const {return location;}
 Type T() const {return type;}

private:
 Type type;
 ObjectBase* obj;
 std::string name;
 struct grammatic_location location;
};

typedef std::list<StackElem> ExecExpr;

inline StackElem SEBList(const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_BEGINLIST,loc);}
inline StackElem SEEList(const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_ENDLIST,loc);}
inline StackElem SEObj(ObjectBase* o, const struct grammatic_location& loc) {return StackElem(o,loc);}
inline StackElem SEMKPair(const std::string& s, const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_MKPAIR,loc,s);}
inline StackElem SEVar(const std::string& s, const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_VARIABLE,loc,s);}
inline StackElem SEFunc(const std::string& s, const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_FUNCTION,loc,s);}
inline StackElem SEMKPair(const std::string* s, const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_MKPAIR,loc,*s);}
inline StackElem SEVar(const std::string* s, const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_VARIABLE,loc,*s);}
inline StackElem SEFunc(const std::string* s, const struct grammatic_location& loc) {return StackElem(StackElem::TYPE_FUNCTION,loc,*s);}

std::string DumpExprE(const ExecExpr& exp);
std::string DumpExpr(const ExecExpr& exp);
UsedType UsedVars(const ExecExpr& exp);
UsedType UsedFuncs(const ExecExpr& exp);
ObjectBase* Evaluate(ExecExpr& exp, bool* err);
//inline void ReplaceVar(ExecExpr& exp, const std::string& var, ObjectBase* ob) {for(auto& se: exp) if(se.isVar() && var==se.Name()) se.ReplaceByObject(ob);}
void ReplaceVar(ExecExpr& exp, const std::string& var, const ObjectBase* ob);// {for(auto& se: exp) if(se.isVar() && var==se.Name()) se.ReplaceByObject(ob);}

#endif