//===-- llvm-rc.cpp - Compile .rc scripts into .res -------------*- 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
//
//===----------------------------------------------------------------------===//
//
// Compile .rc scripts into .res files. This is intended to be a
// platform-independent port of Microsoft's rc.exe tool.
//
//===----------------------------------------------------------------------===//

#include "ResourceFileWriter.h"
#include "ResourceScriptCppFilter.h"
#include "ResourceScriptParser.h"
#include "ResourceScriptStmt.h"
#include "ResourceScriptToken.h"

#include "llvm/ADT/Triple.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/InitLLVM.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/StringSaver.h"
#include "llvm/Support/raw_ostream.h"

#include <algorithm>
#include <system_error>

using namespace llvm;
using namespace llvm::rc;

namespace {

// Input options tables.

enum ID {
  OPT_INVALID = 0, // This is not a correct option ID.
#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
               HELPTEXT, METAVAR, VALUES)                                      \
  OPT_##ID,
#include "Opts.inc"
#undef OPTION
};

#define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
#include "Opts.inc"
#undef PREFIX

static const opt::OptTable::Info InfoTable[] = {
#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
               HELPTEXT, METAVAR, VALUES)                                      \
  {                                                                            \
      PREFIX,      NAME,      HELPTEXT,                                        \
      METAVAR,     OPT_##ID,  opt::Option::KIND##Class,                        \
      PARAM,       FLAGS,     OPT_##GROUP,                                     \
      OPT_##ALIAS, ALIASARGS, VALUES},
#include "Opts.inc"
#undef OPTION
};

class RcOptTable : public opt::OptTable {
public:
  RcOptTable() : OptTable(InfoTable, /* IgnoreCase = */ true) {}
};

static ExitOnError ExitOnErr;
static FileRemover TempPreprocFile;

LLVM_ATTRIBUTE_NORETURN static void fatalError(const Twine &Message) {
  errs() << Message << "\n";
  exit(1);
}

std::string createTempFile(const Twine &Prefix, StringRef Suffix) {
  std::error_code EC;
  SmallString<128> FileName;
  if ((EC = sys::fs::createTemporaryFile(Prefix, Suffix, FileName)))
    fatalError("Unable to create temp file: " + EC.message());
  return static_cast<std::string>(FileName);
}

ErrorOr<std::string> findClang(const char *Argv0) {
  StringRef Parent = llvm::sys::path::parent_path(Argv0);
  ErrorOr<std::string> Path = std::error_code();
  if (!Parent.empty()) {
    // First look for the tool with all potential names in the specific
    // directory of Argv0, if known
    for (const auto *Name : {"clang", "clang-cl"}) {
      Path = sys::findProgramByName(Name, Parent);
      if (Path)
        return Path;
    }
  }
  // If no parent directory known, or not found there, look everywhere in PATH
  for (const auto *Name : {"clang", "clang-cl"}) {
    Path = sys::findProgramByName(Name);
    if (Path)
      return Path;
  }
  return Path;
}

std::string getClangClTriple() {
  Triple T(sys::getDefaultTargetTriple());
  T.setOS(llvm::Triple::Win32);
  T.setVendor(llvm::Triple::PC);
  T.setEnvironment(llvm::Triple::MSVC);
  T.setObjectFormat(llvm::Triple::COFF);
  return T.str();
}

bool preprocess(StringRef Src, StringRef Dst, opt::InputArgList &InputArgs,
                const char *Argv0) {
  std::string Clang;
  if (InputArgs.hasArg(OPT__HASH_HASH_HASH)) {
    Clang = "clang";
  } else {
    ErrorOr<std::string> ClangOrErr = findClang(Argv0);
    if (ClangOrErr) {
      Clang = *ClangOrErr;
    } else {
      errs() << "llvm-rc: Unable to find clang, skipping preprocessing."
             << "\n";
      errs() << "Pass -no-cpp to disable preprocessing. This will be an error "
                "in the future."
             << "\n";
      return false;
    }
  }
  std::string PreprocTriple = getClangClTriple();

  SmallVector<StringRef, 8> Args = {
      Clang, "--driver-mode=gcc", "-target", PreprocTriple, "-E",
      "-xc", "-DRC_INVOKED",      Src,       "-o",          Dst};
  if (InputArgs.hasArg(OPT_noinclude)) {
#ifdef _WIN32
    ::_putenv("INCLUDE=");
#else
    ::unsetenv("INCLUDE");
#endif
  }
  for (const auto *Arg :
       InputArgs.filtered(OPT_includepath, OPT_define, OPT_undef)) {
    switch (Arg->getOption().getID()) {
    case OPT_includepath:
      Args.push_back("-I");
      break;
    case OPT_define:
      Args.push_back("-D");
      break;
    case OPT_undef:
      Args.push_back("-U");
      break;
    }
    Args.push_back(Arg->getValue());
  }
  if (InputArgs.hasArg(OPT__HASH_HASH_HASH) || InputArgs.hasArg(OPT_verbose)) {
    for (const auto &A : Args) {
      outs() << " ";
      sys::printArg(outs(), A, InputArgs.hasArg(OPT__HASH_HASH_HASH));
    }
    outs() << "\n";
    if (InputArgs.hasArg(OPT__HASH_HASH_HASH))
      exit(0);
  }
  // The llvm Support classes don't handle reading from stdout of a child
  // process; otherwise we could avoid using a temp file.
  int Res = sys::ExecuteAndWait(Clang, Args);
  if (Res) {
    fatalError("llvm-rc: Preprocessing failed.");
  }
  return true;
}

} // anonymous namespace

int main(int Argc, const char **Argv) {
  InitLLVM X(Argc, Argv);
  ExitOnErr.setBanner("llvm-rc: ");

  RcOptTable T;
  unsigned MAI, MAC;
  const char **DashDash = std::find_if(
      Argv + 1, Argv + Argc, [](StringRef Str) { return Str == "--"; });
  ArrayRef<const char *> ArgsArr = makeArrayRef(Argv + 1, DashDash);

  opt::InputArgList InputArgs = T.ParseArgs(ArgsArr, MAI, MAC);

  // The tool prints nothing when invoked with no command-line arguments.
  if (InputArgs.hasArg(OPT_help)) {
    T.PrintHelp(outs(), "rc [options] file...", "Resource Converter", false);
    return 0;
  }

  const bool BeVerbose = InputArgs.hasArg(OPT_verbose);

  std::vector<std::string> InArgsInfo = InputArgs.getAllArgValues(OPT_INPUT);
  if (DashDash != Argv + Argc)
    InArgsInfo.insert(InArgsInfo.end(), DashDash + 1, Argv + Argc);
  if (InArgsInfo.size() != 1) {
    fatalError("Exactly one input file should be provided.");
  }

  std::string PreprocessedFile = InArgsInfo[0];
  if (!InputArgs.hasArg(OPT_no_preprocess)) {
    std::string OutFile = createTempFile("preproc", "rc");
    TempPreprocFile.setFile(OutFile);
    if (preprocess(InArgsInfo[0], OutFile, InputArgs, Argv[0]))
      PreprocessedFile = OutFile;
  }

  // Read and tokenize the input file.
  ErrorOr<std::unique_ptr<MemoryBuffer>> File =
      MemoryBuffer::getFile(PreprocessedFile);
  if (!File) {
    fatalError("Error opening file '" + Twine(InArgsInfo[0]) +
               "': " + File.getError().message());
  }

  std::unique_ptr<MemoryBuffer> FileContents = std::move(*File);
  StringRef Contents = FileContents->getBuffer();

  std::string FilteredContents = filterCppOutput(Contents);
  std::vector<RCToken> Tokens = ExitOnErr(tokenizeRC(FilteredContents));

  if (BeVerbose) {
    const Twine TokenNames[] = {
#define TOKEN(Name) #Name,
#define SHORT_TOKEN(Name, Ch) #Name,
#include "ResourceScriptTokenList.def"
    };

    for (const RCToken &Token : Tokens) {
      outs() << TokenNames[static_cast<int>(Token.kind())] << ": "
             << Token.value();
      if (Token.kind() == RCToken::Kind::Int)
        outs() << "; int value = " << Token.intValue();

      outs() << "\n";
    }
  }

  WriterParams Params;
  SmallString<128> InputFile(InArgsInfo[0]);
  llvm::sys::fs::make_absolute(InputFile);
  Params.InputFilePath = InputFile;
  Params.Include = InputArgs.getAllArgValues(OPT_includepath);
  Params.NoInclude = InputArgs.hasArg(OPT_noinclude);

  if (InputArgs.hasArg(OPT_codepage)) {
    if (InputArgs.getLastArgValue(OPT_codepage)
            .getAsInteger(10, Params.CodePage))
      fatalError("Invalid code page: " +
                 InputArgs.getLastArgValue(OPT_codepage));
    switch (Params.CodePage) {
    case CpAcp:
    case CpWin1252:
    case CpUtf8:
      break;
    default:
      fatalError(
          "Unsupported code page, only 0, 1252 and 65001 are supported!");
    }
  }

  std::unique_ptr<ResourceFileWriter> Visitor;
  bool IsDryRun = InputArgs.hasArg(OPT_dry_run);

  if (!IsDryRun) {
    auto OutArgsInfo = InputArgs.getAllArgValues(OPT_fileout);
    if (OutArgsInfo.empty()) {
      SmallString<128> OutputFile = InputFile;
      llvm::sys::path::replace_extension(OutputFile, "res");
      OutArgsInfo.push_back(std::string(OutputFile.str()));
    }

    if (OutArgsInfo.size() != 1)
      fatalError(
          "No more than one output file should be provided (using /FO flag).");

    std::error_code EC;
    auto FOut = std::make_unique<raw_fd_ostream>(
        OutArgsInfo[0], EC, sys::fs::FA_Read | sys::fs::FA_Write);
    if (EC)
      fatalError("Error opening output file '" + OutArgsInfo[0] +
                 "': " + EC.message());
    Visitor = std::make_unique<ResourceFileWriter>(Params, std::move(FOut));
    Visitor->AppendNull = InputArgs.hasArg(OPT_add_null);

    ExitOnErr(NullResource().visit(Visitor.get()));

    // Set the default language; choose en-US arbitrarily.
    unsigned PrimaryLangId = 0x09, SubLangId = 0x01;
    if (InputArgs.hasArg(OPT_lang_id)) {
      unsigned LangId;
      if (InputArgs.getLastArgValue(OPT_lang_id).getAsInteger(16, LangId))
        fatalError("Invalid language id: " +
                   InputArgs.getLastArgValue(OPT_lang_id));
      PrimaryLangId = LangId & 0x3ff;
      SubLangId = LangId >> 10;
    }
    ExitOnErr(LanguageResource(PrimaryLangId, SubLangId).visit(Visitor.get()));
  }

  rc::RCParser Parser{std::move(Tokens)};
  while (!Parser.isEof()) {
    auto Resource = ExitOnErr(Parser.parseSingleResource());
    if (BeVerbose)
      Resource->log(outs());
    if (!IsDryRun)
      ExitOnErr(Resource->visit(Visitor.get()));
  }

  // STRINGTABLE resources come at the very end.
  if (!IsDryRun)
    ExitOnErr(Visitor->dumpAllStringTables());

  return 0;
}