//===--- TokenAnalyzer.cpp - Analyze Token Streams --------------*- 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

//

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

///

/// \file

/// This file implements an abstract TokenAnalyzer and associated helper

/// classes. TokenAnalyzer can be extended to generate replacements based on

/// an annotated and pre-processed token stream.

///

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

#include "TokenAnalyzer.h"

#include "AffectedRangeManager.h"

#include "Encoding.h"

#include "FormatToken.h"

#include "FormatTokenLexer.h"

#include "TokenAnnotator.h"

#include "UnwrappedLineParser.h"

#include "clang/Basic/Diagnostic.h"

#include "clang/Basic/DiagnosticOptions.h"

#include "clang/Basic/FileManager.h"

#include "clang/Basic/SourceManager.h"

#include "clang/Format/Format.h"

#include "llvm/ADT/STLExtras.h"

#include "llvm/ADT/SmallVector.h"

#include "llvm/Support/Debug.h"

#include <type_traits>

#define DEBUG_TYPE "format-formatter"

namespace clang {

namespace format {

// FIXME: Instead of printing the diagnostic we should store it and have a

// better way to return errors through the format APIs.

class FatalDiagnosticConsumer : public DiagnosticConsumer {

public:

  void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,

                        const Diagnostic &Info) override {

    if (DiagLevel == DiagnosticsEngine::Fatal) {

      Fatal = true;

      llvm::SmallVector<char, 128> Message;

      Info.FormatDiagnostic(Message);

      llvm::errs() << Message << "\n";

    }

  }

  bool fatalError() const { return Fatal; }

private:

  bool Fatal = false;

};

std::unique_ptr<Environment>

Environment::make(StringRef Code, StringRef FileName,

                  ArrayRef<tooling::Range> Ranges, unsigned FirstStartColumn,

                  unsigned NextStartColumn, unsigned LastStartColumn) {

  auto Env = std::make_unique<Environment>(Code, FileName, FirstStartColumn,

                                           NextStartColumn, LastStartColumn);

  FatalDiagnosticConsumer Diags;

  Env->SM.getDiagnostics().setClient(&Diags, /*ShouldOwnClient=*/false);

  SourceLocation StartOfFile = Env->SM.getLocForStartOfFile(Env->ID);

  for (const tooling::Range &Range : Ranges) {

    SourceLocation Start = StartOfFile.getLocWithOffset(Range.getOffset());

    SourceLocation End = Start.getLocWithOffset(Range.getLength());

    Env->CharRanges.push_back(CharSourceRange::getCharRange(Start, End));

  }

  // Validate that we can get the buffer data without a fatal error.

  Env->SM.getBufferData(Env->ID);

  if (Diags.fatalError())

    return nullptr;

  return Env;

}

Environment::Environment(StringRef Code, StringRef FileName,

                         unsigned FirstStartColumn, unsigned NextStartColumn,

                         unsigned LastStartColumn)

    : VirtualSM(new SourceManagerForFile(FileName, Code)), SM(VirtualSM->get()),

      ID(VirtualSM->get().getMainFileID()), FirstStartColumn(FirstStartColumn),

      NextStartColumn(NextStartColumn), LastStartColumn(LastStartColumn) {}

TokenAnalyzer::TokenAnalyzer(const Environment &Env, const FormatStyle &Style)

    : Style(Style), Env(Env),

      AffectedRangeMgr(Env.getSourceManager(), Env.getCharRanges()),

      UnwrappedLines(1),

      Encoding(encoding::detectEncoding(

          Env.getSourceManager().getBufferData(Env.getFileID()))) {

  LLVM_DEBUG(

      llvm::dbgs() << "File encoding: "

                   << (Encoding == encoding::Encoding_UTF8 ? "UTF8" : "unknown")

                   << "\n");

  LLVM_DEBUG(llvm::dbgs() << "Language: " << getLanguageName(Style.Language)

                          << "\n");

}

std::pair<tooling::Replacements, unsigned> TokenAnalyzer::process() {

  tooling::Replacements Result;

  llvm::SpecificBumpPtrAllocator<FormatToken> Allocator;

  IdentifierTable IdentTable(getFormattingLangOpts(Style));

  FormatTokenLexer Lex(Env.getSourceManager(), Env.getFileID(),

                       Env.getFirstStartColumn(), Style, Encoding, Allocator,

                       IdentTable);

  ArrayRef<FormatToken *> Toks(Lex.lex());

  SmallVector<FormatToken *, 10> Tokens(Toks.begin(), Toks.end());

  UnwrappedLineParser Parser(Style, Lex.getKeywords(),

                             Env.getFirstStartColumn(), Tokens, *this);

  Parser.parse();

  assert(UnwrappedLines.back().empty());

  unsigned Penalty = 0;

  for (unsigned Run = 0, RunE = UnwrappedLines.size(); Run + 1 != RunE; 
++Run64.9k
) {

    const auto &Lines = UnwrappedLines[Run];

    LLVM_DEBUG(llvm::dbgs() << "Run " << Run << "...\n");

    SmallVector<AnnotatedLine *, 16> AnnotatedLines;

    AnnotatedLines.reserve(Lines.size());

    TokenAnnotator Annotator(Style, Lex.getKeywords());

    for (const UnwrappedLine &Line : Lines) {

      AnnotatedLines.push_back(new AnnotatedLine(Line));

      Annotator.annotate(*AnnotatedLines.back());

    }

    std::pair<tooling::Replacements, unsigned> RunResult =

        analyze(Annotator, AnnotatedLines, Lex);

    LLVM_DEBUG({

      llvm::dbgs() << "Replacements for run " << Run << ":\n";

      for (const tooling::Replacement &Fix : RunResult.first)

        llvm::dbgs() << Fix.toString() << "\n";

    });

    for (AnnotatedLine *Line : AnnotatedLines)

      delete Line;

    Penalty += RunResult.second;

    for (const auto &R : RunResult.first) {

      auto Err = Result.add(R);

      // FIXME: better error handling here. For now, simply return an empty

      // Replacements to indicate failure.

      if (Err) {

        llvm::errs() << llvm::toString(std::move(Err)) << "\n";

        return {tooling::Replacements(), 0};

      }

    }

  }

  return {Result, Penalty};

}

void TokenAnalyzer::consumeUnwrappedLine(const UnwrappedLine &TheLine) {

  assert(!UnwrappedLines.empty());

  UnwrappedLines.back().push_back(TheLine);

}

void TokenAnalyzer::finishRun() {

  UnwrappedLines.push_back(SmallVector<UnwrappedLine, 16>());

}

} // end namespace format

} // end namespace clang