#include "TclUtil.h"

std::string getString(Tcl_Obj *obj)
{
  int length;
  char *body = Tcl_GetStringFromObj(obj, &length);
  return std::string(body, length);
}

Tcl_Obj *makeTclString(std::string const &s)
{
  return Tcl_NewStringObj(s.data(), s.size());
}

int convertFromTcl(Tcl_Interp *interp, int &destination, Tcl_Obj *source)
{
  return Tcl_GetIntFromObj(interp, source, &destination);
}

int convertFromTcl(Tcl_Interp *interp, bool &destination, Tcl_Obj *source)
{
  int value;
  const int result = Tcl_GetBooleanFromObj(interp, source, &value);
  if (result != TCL_OK)
    return TCL_ERROR;
  destination = value;
  return TCL_OK;
}

int convertFromTcl(Tcl_Interp *interp, double &destination, Tcl_Obj *source)
{
  return Tcl_GetDoubleFromObj(interp, source, &destination);
}

int convertFromTcl(Tcl_Interp *interp, std::string &destination,
                   Tcl_Obj *source)
{ // By itself this function isn't very interesting.  It's just a wrapper
  // around getString.  But this can work with a vector of strings, or a
  // map from strings to something else.
  destination = getString(source);
  return TCL_OK;
}

/*
static int convertFromTclHelper(Tcl_Interp *interp, 
				IConvertFromTclList &destination,
				Tcl_Obj *source)
{
  int count;
  Tcl_Obj **items;
  if (Tcl_ListObjGetElements(interp, source, &count, &items) != TCL_OK)
    return TCL_ERROR;
  if (destination.init(interp, count) != TCL_OK)
    return TCL_ERROR;
  for (int i = 0; i < count; i++)
    if (destination.add(interp, items[i]) != TCL_OK)
      return TCL_ERROR;
  return destination.commit(interp);
}

int IConvertFromTclList::load(Tcl_Interp *interp, Tcl_Obj *source)
{
  if (convertFromTclHelper(interp, *this, source) != TCL_OK)
  {
    rollback();
    return TCL_ERROR;
  }
  if (commit(interp) == TCL_OK)
    return TCL_OK;
  else
    return TCL_ERROR;
}

int convertFromTcl(Tcl_Interp *interp, IConvertFromTcl &destination,
                   Tcl_Obj *source)
{
  return destination.convertFromTcl(interp, source);
}
*/

int convertFromTcl(Tcl_Interp *interp, TclObjHolder &destination,
                   Tcl_Obj *source)
{
  destination = source;
  return TCL_OK;
}

int dictGetIfExists(Tcl_Interp *interp, Tcl_Obj *dict, std::string name,
		    int &out)
{
  TclObjHolder key = makeTclString(name);
  TclObjHolder value;
  {
    Tcl_Obj *valueTemp;
    int result = Tcl_DictObjGet(interp, dict, key.getObj(), &valueTemp);
    if (result != TCL_OK)
      return TCL_ERROR;
    value = valueTemp;
  }
  if (!value)
    // Key not found.  This is not an error.  Leave out as it was.  The caller
    // should preload that with a default.
    return TCL_OK;
  return Tcl_GetIntFromObj(interp, value.getObj(), &out);
}

int dictGetIfExists(Tcl_Interp *interp, Tcl_Obj *dict, std::string name,
		    long &out)
{
  TclObjHolder key = makeTclString(name);
  TclObjHolder value;
  {
    Tcl_Obj *valueTemp;
    int result = Tcl_DictObjGet(interp, dict, key.getObj(), &valueTemp);
    if (result != TCL_OK)
      return TCL_ERROR;
    value = valueTemp;
  }
  if (!value)
    // Key not found.  This is not an error.  Leave out as it was.  The caller
    // should preload that with a default.
    return TCL_OK;
  return Tcl_GetLongFromObj(interp, value.getObj(), &out);
}

int dictGetIfExists(Tcl_Interp *interp, Tcl_Obj *dict, std::string name,
		    bool &out)
{
  TclObjHolder key = makeTclString(name);
  TclObjHolder value;
  {
    Tcl_Obj *valueTemp;
    int result = Tcl_DictObjGet(interp, dict, key.getObj(), &valueTemp);
    if (result != TCL_OK)
      return TCL_ERROR;
    value = valueTemp;
  }
  if (!value)
    // Key not found.  This is not an error.  Leave out as it was.  The caller
    // should preload that with a default.
    return TCL_OK;
  int outTemp;
  int result = Tcl_GetBooleanFromObj(interp, value.getObj(), &outTemp);
  if (result == TCL_OK)
    out = outTemp;
  return result;
}

int dictGetIfExists(Tcl_Interp *interp, Tcl_Obj *dict, std::string name,
		    std::string &out)
{
  TclObjHolder key = makeTclString(name);
  TclObjHolder value;
  {
    Tcl_Obj *valueTemp;
    int result = Tcl_DictObjGet(interp, dict, key.getObj(), &valueTemp);
    if (result != TCL_OK)
      return TCL_ERROR;
    value = valueTemp;
  }
  if (value)
    // Key found!
    out = getString(value.getObj());
  return TCL_OK;
}

int listToVector(Tcl_Interp *interp, Tcl_Obj *source, 
		 std::vector< Tcl_Obj * > &appendTo)
{
  int objc;
  Tcl_Obj **objv;
  if (Tcl_ListObjGetElements(interp, source, &objc, &objv) != TCL_OK)
    return TCL_ERROR;
  while (objc)
    {
      objc--;
      appendTo.push_back(*objv);
      objv++;
    }
  return TCL_OK;
}