/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "txExpr.h"
#include "nsAtom.h"
#include "txNodeSet.h"
#include "nsGkAtoms.h"
#include "txIXPathContext.h"

//-------------------/
//- VariableRefExpr -/
//-------------------/

/**
 * Creates a VariableRefExpr with the given variable name
 **/
VariableRefExpr::VariableRefExpr(nsAtom* aPrefix, nsAtom* aLocalName,
                                 int32_t aNSID)
    : mPrefix(aPrefix), mLocalName(aLocalName), mNamespace(aNSID) {
  NS_ASSERTION(mLocalName, "VariableRefExpr without local name?");
  if (mPrefix == nsGkAtoms::_empty) mPrefix = nullptr;
}

/**
 * Evaluates this Expr based on the given context node and processor state
 * @param context the context node for evaluation of this Expr
 * @param ps the ContextState containing the stack information needed
 * for evaluation
 * @return the result of the evaluation
 **/
nsresult VariableRefExpr::evaluate(txIEvalContext* aContext,
                                   txAExprResult** aResult) {
  nsresult rv = aContext->getVariable(mNamespace, mLocalName, *aResult);
  if (NS_FAILED(rv)) {
    // XXX report error, undefined variable
    return rv;
  }
  return NS_OK;
}

TX_IMPL_EXPR_STUBS_0(VariableRefExpr, ANY_RESULT)

bool VariableRefExpr::isSensitiveTo(ContextSensitivity aContext) {
  return !!(aContext & VARIABLES_CONTEXT);
}

#ifdef TX_TO_STRING
void VariableRefExpr::toString(nsAString& aDest) {
  aDest.Append(char16_t('$'));
  if (mPrefix) {
    nsAutoString prefix;
    mPrefix->ToString(prefix);
    aDest.Append(prefix);
    aDest.Append(char16_t(':'));
  }
  nsAutoString lname;
  mLocalName->ToString(lname);
  aDest.Append(lname);
}
#endif
