//===- TokenRewriter.h - Token-based Rewriter -------------------*- 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

//

//===----------------------------------------------------------------------===//

//

//  This file defines the TokenRewriter class, which is used for code

//  transformations.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_REWRITE_CORE_TOKENREWRITER_H

#define LLVM_CLANG_REWRITE_CORE_TOKENREWRITER_H

#include "clang/Basic/SourceLocation.h"

#include "clang/Lex/Token.h"

#include <cassert>

#include <list>

#include <map>

#include <memory>

namespace clang {

class LangOptions;

class ScratchBuffer;

class SourceManager;

  class TokenRewriter {

    /// TokenList - This is the list of raw tokens that make up this file.  Each

    /// of these tokens has a unique SourceLocation, which is a FileID.

    std::list<Token> TokenList;

    /// TokenRefTy - This is the type used to refer to a token in the TokenList.

    using TokenRefTy = std::list<Token>::iterator;

    /// TokenAtLoc - This map indicates which token exists at a specific

    /// SourceLocation.  Since each token has a unique SourceLocation, this is a

    /// one to one map.  The token can return its own location directly, to map

    /// backwards.

    std::map<SourceLocation, TokenRefTy> TokenAtLoc;

    /// ScratchBuf - This is the buffer that we create scratch tokens from.

    std::unique_ptr<ScratchBuffer> ScratchBuf;

  public:

    /// TokenRewriter - This creates a TokenRewriter for the file with the

    /// specified FileID.

    TokenRewriter(FileID FID, SourceManager &SM, const LangOptions &LO);

    TokenRewriter(const TokenRewriter &) = delete;

    TokenRewriter &operator=(const TokenRewriter &) = delete;

    ~TokenRewriter();

    using token_iterator = std::list<Token>::const_iterator;

    token_iterator token_begin() const { return TokenList.begin(); }

    token_iterator token_end() const { return TokenList.end(); }

    token_iterator AddTokenBefore(token_iterator I, const char *Val);

    token_iterator AddTokenAfter(token_iterator I, const char *Val) {

      assert(I != token_end() && "Cannot insert after token_end()!");

      return AddTokenBefore(++I, Val);

    }

  private:

    /// RemapIterator - Convert from token_iterator (a const iterator) to

    /// TokenRefTy (a non-const iterator).

    TokenRefTy RemapIterator(token_iterator I);

    /// AddToken - Add the specified token into the Rewriter before the other

    /// position.

    TokenRefTy AddToken(const Token &T, TokenRefTy Where);

  };

} // namespace clang

#endif // LLVM_CLANG_REWRITE_CORE_TOKENREWRITER_H