//===--- ObjcLocalizeStringLiteral.cpp ---------------------------*- C++-*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "Logger.h"
#include "ParsedAST.h"
#include "SourceCode.h"
#include "refactor/Tweak.h"
#include "clang/AST/ExprObjC.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/SourceLocation.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Tooling/Core/Replacement.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Error.h"

namespace clang {
namespace clangd {
namespace {

/// Wraps an Objective-C string literal with the NSLocalizedString macro.
/// Before:
///   @"description"
///   ^^^
/// After:
///   NSLocalizedString(@"description", @"")
class ObjCLocalizeStringLiteral : public Tweak {
public:
  const char *id() const override final;
  Intent intent() const override { return Intent::Refactor; }

  bool prepare(const Selection &Inputs) override;
  Expected<Tweak::Effect> apply(const Selection &Inputs) override;
  std::string title() const override;

private:
  const clang::ObjCStringLiteral *Str = nullptr;
};

REGISTER_TWEAK(ObjCLocalizeStringLiteral)

bool ObjCLocalizeStringLiteral::prepare(const Selection &Inputs) {
  const SelectionTree::Node *N = Inputs.ASTSelection.commonAncestor();
  if (!N)
    return false;
  // Allow the refactoring even if the user selected only the C string part
  // of the expression.
  if (N->ASTNode.get<StringLiteral>()) {
    if (N->Parent)
      N = N->Parent;
  }
  Str = dyn_cast_or_null<ObjCStringLiteral>(N->ASTNode.get<Stmt>());
  return Str;
}

Expected<Tweak::Effect>
ObjCLocalizeStringLiteral::apply(const Selection &Inputs) {
  auto &SM = Inputs.AST->getSourceManager();
  auto &LangOpts = Inputs.AST->getASTContext().getLangOpts();
  auto Reps = tooling::Replacements(tooling::Replacement(
      SM, CharSourceRange::getCharRange(Str->getBeginLoc()),
      "NSLocalizedString(", LangOpts));
  SourceLocation EndLoc = Lexer::getLocForEndOfToken(
      Str->getEndLoc(), 0, Inputs.AST->getSourceManager(), LangOpts);
  if (auto Err = Reps.add(tooling::Replacement(
          SM, CharSourceRange::getCharRange(EndLoc), ", @\"\")", LangOpts)))
    return std::move(Err);
  return Effect::mainFileEdit(SM, std::move(Reps));
}

std::string ObjCLocalizeStringLiteral::title() const {
  return "Wrap in NSLocalizedString";
}

} // namespace
} // namespace clangd
} // namespace clang