/* vim:set ts=2 sw=2 sts=2 et: */
/**
 * \author     Marcus Holland-Moritz (github@mhxnet.de)
 * \copyright  Copyright (c) Marcus Holland-Moritz
 *
 * This file is part of dwarfs.
 *
 * dwarfs is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * dwarfs is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with dwarfs.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <algorithm>
#include <cstdlib>
#include <filesystem>
#include <iostream>
#include <map>
#include <string_view>
#include <vector>

#include <folly/String.h>
#include <folly/gen/String.h>
#include <folly/portability/Windows.h>

#include "dwarfs/safe_main.h"
#include "dwarfs/tool.h"
#include "dwarfs/util.h"
#include "dwarfs_tool_main.h"

namespace {

using namespace dwarfs;

#ifdef _WIN32
#define EXE_EXT ".exe"
#else
#define EXE_EXT ""
#endif

std::map<std::string_view, int (*)(int, sys_char**)> const functions{
    {"dwarfs", &dwarfs_main},
    {"mkdwarfs", &mkdwarfs_main},
    {"dwarfsck", &dwarfsck_main},
    {"dwarfsextract", &dwarfsextract_main},
    // {"dwarfsbench", &dwarfsbench_main},
};

} // namespace

int SYS_MAIN(int argc, sys_char** argv) {
  auto path = std::filesystem::path(argv[0]);

  // first, see if we are called as a copy/hardlink/symlink

  if (auto ext = path.extension().string(); ext.empty() || ext == EXE_EXT) {
    if (auto it = functions.find(path.stem().string()); it != functions.end()) {
      return safe_main([&] { return it->second(argc, argv); });
    }
  }

  // if not, see if we can find a --tool=... argument

  if (argc > 1) {
    auto tool_arg = sys_string_to_string(argv[1]);
    if (tool_arg.starts_with("--tool=")) {
      if (auto it = functions.find(tool_arg.substr(7)); it != functions.end()) {
        std::vector<sys_char*> argv_copy;
        argv_copy.reserve(argc - 1);
        argv_copy.emplace_back(argv[0]);
        std::copy(argv + 2, argv + argc, std::back_inserter(argv_copy));
        return safe_main(
            [&] { return it->second(argc - 1, argv_copy.data()); });
      }
    }
  }

  // nope, just print the help

  using namespace folly::gen;

  // TODO: C++23
  // auto tools = std::views::keys(functions) | std::views::join_with(", ");
  auto tools = from(functions) | get<0>() | unsplit(", ");

  // clang-format off
  std::cout << tool_header("dwarfs-universal")
            << "Command line options:\n"
            << "  --tool=<name>                     "
                 "which tool to run; available tools are:\n"
            << "                                    "
            << tools << "\n\n";
  // clang-format on

  return 0;
}