//===--- SerializablePathCollection.h -- Index of paths ---------*- 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

//

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

#ifndef LLVM_CLANG_INDEXSERIALIZATION_SERIALIZABLEPATHCOLLECTION_H

#define LLVM_CLANG_INDEXSERIALIZATION_SERIALIZABLEPATHCOLLECTION_H

#include "clang/Basic/FileManager.h"

#include "llvm/ADT/APInt.h"

#include "llvm/ADT/DenseMap.h"

#include "llvm/ADT/Optional.h"

#include "llvm/ADT/SmallString.h"

#include "llvm/ADT/StringMap.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/ADT/iterator.h"

#include <string>

#include <vector>

namespace clang {

namespace index {

/// Pool of strings

class StringPool {

  llvm::SmallString<512> Buffer;

public:

  struct StringOffsetSize {

    std::size_t Offset;

    std::size_t Size;

    StringOffsetSize(size_t Offset, size_t Size) : Offset(Offset), Size(Size) {}

  };

  StringOffsetSize add(StringRef Str);

  StringRef getBuffer() const { return Buffer; }

};

/// Pool of filesystem paths backed by a StringPool

class PathPool {

public:

  /// Special root directory of a filesystem path.

  enum class RootDirKind {

    Regular = 0,

    CurrentWorkDir = 1,

    SysRoot = 2,

  };

  struct DirPath {

    RootDirKind Root;

    StringPool::StringOffsetSize Path;

    DirPath(RootDirKind Root, const StringPool::StringOffsetSize &Path)

        : Root(Root), Path(Path) {}

  };

  struct FilePath {

    DirPath Dir;

    StringPool::StringOffsetSize Filename;

    FilePath(const DirPath &Dir, const StringPool::StringOffsetSize &Filename)

        : Dir(Dir), Filename(Filename) {}

  };

  /// \returns index of the newly added file in FilePaths.

  size_t addFilePath(RootDirKind Root, const StringPool::StringOffsetSize &Dir,

                     StringRef Filename);

  /// \returns offset in Paths and size of newly added directory.

  StringPool::StringOffsetSize addDirPath(StringRef Dir);

  llvm::ArrayRef<FilePath> getFilePaths() const;

  StringRef getPaths() const;

private:

  StringPool Paths;

  std::vector<FilePath> FilePaths;

};

/// Stores file paths and produces serialization-friendly representation.

class SerializablePathCollection {

  std::string WorkDir;

  std::string SysRoot;

  PathPool Paths;

  llvm::DenseMap<const clang::FileEntry *, std::size_t> UniqueFiles;

  llvm::StringMap<PathPool::DirPath, llvm::BumpPtrAllocator> UniqueDirs;

public:

  const StringPool::StringOffsetSize WorkDirPath;

  const StringPool::StringOffsetSize SysRootPath;

  const StringPool::StringOffsetSize OutputFilePath;

  SerializablePathCollection(llvm::StringRef CurrentWorkDir,

                             llvm::StringRef SysRoot,

                             llvm::StringRef OutputFile);

  /// \returns buffer containing all the paths.

  llvm::StringRef getPathsBuffer() const { return Paths.getPaths(); }

  /// \returns file paths (no directories) backed by buffer exposed in

  /// getPathsBuffer.

  ArrayRef<PathPool::FilePath> getFilePaths() const {

    return Paths.getFilePaths();

  }

  /// Stores path to \p FE if it hasn't been stored yet.

  /// \returns index to array exposed by getPathsBuffer().

  size_t tryStoreFilePath(const clang::FileEntry &FE);

private:

  /// Stores \p Path if it is non-empty.

  /// Warning: this method doesn't check for uniqueness.

  /// \returns offset of \p Path value begin in buffer with stored paths.

  StringPool::StringOffsetSize storePath(llvm::StringRef Path);

  /// Stores \p dirStr path if it hasn't been stored yet.

  PathPool::DirPath tryStoreDirPath(llvm::StringRef dirStr);

};

} // namespace index

} // namespace clang

#endif // LLVM_CLANG_INDEXSERIALIZATION_SERIALIZABLEPATHCOLLECTION_H