//===--- CLI.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 "clang-pseudo/cli/CLI.h"

#include "clang-pseudo/cxx/CXX.h"

#include "clang-pseudo/grammar/Grammar.h"

#include "llvm/Support/CommandLine.h"

#include "llvm/Support/ErrorOr.h"

#include "llvm/Support/MemoryBuffer.h"

static llvm::cl::opt<std::string> Grammar(

    "grammar",

    llvm::cl::desc(

        "Specify a BNF grammar file path, or a builtin language (cxx)."),

    llvm::cl::init("cxx"));

namespace clang {

namespace pseudo {

const Language &getLanguageFromFlags() {

  if (::Grammar == "cxx")

    return cxx::getLanguage();

  static Language *Lang = []() {

    // Read from a bnf grammar file.

    llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> GrammarText =

        llvm::MemoryBuffer::getFile(::Grammar);

    if (std::error_code EC = GrammarText.getError()) {

      llvm::errs() << "Error: can't read grammar file '" << ::Grammar

                   << "': " << EC.message() << "\n";

      std::exit(1);

    }

    std::vector<std::string> Diags;

    auto G = Grammar::parseBNF(GrammarText->get()->getBuffer(), Diags);

    for (const auto &Diag : Diags)

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

    auto Table = LRTable::buildSLR(G);

    return new Language{

        std::move(G),

        std::move(Table),

        llvm::DenseMap<ExtensionID, RuleGuard>(),

        llvm::DenseMap<ExtensionID, RecoveryStrategy>(),

    };

  }();

  return *Lang;

}

} // namespace pseudo

} // namespace clang