//===- FixItRewriter.h - Fix-It Rewriter Diagnostic Client ------*- 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 is a diagnostic client adaptor that performs rewrites as

// suggested by code modification hints attached to diagnostics. It

// then forwards any diagnostics to the adapted diagnostic client.

//

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

#ifndef LLVM_CLANG_REWRITE_FRONTEND_FIXITREWRITER_H

#define LLVM_CLANG_REWRITE_FRONTEND_FIXITREWRITER_H

#include "clang/Basic/Diagnostic.h"

#include "clang/Basic/LLVM.h"

#include "clang/Basic/SourceLocation.h"

#include "clang/Edit/EditedSource.h"

#include "clang/Rewrite/Core/Rewriter.h"

#include <memory>

#include <string>

#include <utility>

#include <vector>

namespace clang {

class LangOptions;

class SourceManager;

class FixItOptions {

public:

  FixItOptions() = default;

  virtual ~FixItOptions();

  /// This file is about to be rewritten. Return the name of the file

  /// that is okay to write to.

  ///

  /// \param fd out parameter for file descriptor. After the call it may be set

  /// to an open file descriptor for the returned filename, or it will be -1

  /// otherwise.

  virtual std::string RewriteFilename(const std::string &Filename, int &fd) = 0;

  /// True if files should be updated in place. RewriteFilename is only called

  /// if this is false.

  bool InPlace = false;

  /// Whether to abort fixing a file when not all errors could be fixed.

  bool FixWhatYouCan = false;

  /// Whether to only fix warnings and not errors.

  bool FixOnlyWarnings = false;

  /// If true, only pass the diagnostic to the actual diagnostic consumer

  /// if it is an error or a fixit was applied as part of the diagnostic.

  /// It basically silences warnings without accompanying fixits.

  bool Silent = false;

};

class FixItRewriter : public DiagnosticConsumer {

  /// The diagnostics machinery.

  DiagnosticsEngine &Diags;

  edit::EditedSource Editor;

  /// The rewriter used to perform the various code

  /// modifications.

  Rewriter Rewrite;

  /// The diagnostic client that performs the actual formatting

  /// of error messages.

  DiagnosticConsumer *Client;

  std::unique_ptr<DiagnosticConsumer> Owner;

  /// Turn an input path into an output path. NULL implies overwriting

  /// the original.

  FixItOptions *FixItOpts;

  /// The number of rewriter failures.

  unsigned NumFailures = 0;

  /// Whether the previous diagnostic was not passed to the consumer.

  bool PrevDiagSilenced = false;

public:

  /// Initialize a new fix-it rewriter.

  FixItRewriter(DiagnosticsEngine &Diags, SourceManager &SourceMgr,

                const LangOptions &LangOpts, FixItOptions *FixItOpts);

  /// Destroy the fix-it rewriter.

  ~FixItRewriter() override;

  /// Check whether there are modifications for a given file.

  bool IsModified(FileID ID) const {

    return Rewrite.getRewriteBufferFor(ID) != nullptr;

  }

  using iterator = Rewriter::buffer_iterator;

  // Iteration over files with changes.

  iterator buffer_begin() { return Rewrite.buffer_begin(); }

  iterator buffer_end() { return Rewrite.buffer_end(); }

  /// Write a single modified source file.

  ///

  /// \returns true if there was an error, false otherwise.

  bool WriteFixedFile(FileID ID, raw_ostream &OS);

  /// Write the modified source files.

  ///

  /// \returns true if there was an error, false otherwise.

  bool WriteFixedFiles(

    std::vector<std::pair<std::string, std::string>> *RewrittenFiles = nullptr);

  /// IncludeInDiagnosticCounts - This method (whose default implementation

  /// returns true) indicates whether the diagnostics handled by this

  /// DiagnosticConsumer should be included in the number of diagnostics

  /// reported by DiagnosticsEngine.

  bool IncludeInDiagnosticCounts() const override;

  /// HandleDiagnostic - Handle this diagnostic, reporting it to the user or

  /// capturing it to a log as needed.

  void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,

                        const Diagnostic &Info) override;

  /// Emit a diagnostic via the adapted diagnostic client.

  void Diag(SourceLocation Loc, unsigned DiagID);

};

} // namespace clang

#endif // LLVM_CLANG_REWRITE_FRONTEND_FIXITREWRITER_H