#include "dbc_parser.h"

#include <chrono>
#include <filesystem>
#include <fstream>
#include <iostream>
#include <stdexcept>

struct Fixture {
  std::filesystem::path path = std::filesystem::temp_directory_path() /
    ("dbc_parser_test_" + std::to_string (
      std::chrono::steady_clock::now().time_since_epoch().count()) + ".dbc");
  ~Fixture() { std::error_code error; std::filesystem::remove (path, error); }
  void Write (const std::string &text) const {
    std::ofstream output (path);
    output << text;
    if (!output)
      throw std::runtime_error ("Cannot write test fixture.");
  }
};

int main() {
  Fixture fixture;
  int failures = 0;
  std::size_t count = 0U;
  const auto check = [&] (bool passed, const std::string &name) {
    ++count;
    if (!passed) { ++failures; std::cerr << "FAIL: " << name << '\n'; }
  };
  struct ValidCase { const char *line; std::uint32_t id; bool extended; unsigned length; };
  const ValidCase valid[] = {
    {"BO_ 0 Frame: 0 ECU", 0U, false, 0U},
    {"BO_ 2047 Frame: 8 ECU", 2047U, false, 8U},
    {"BO_ 2048 Frame: 64 ECU", 2048U, true, 64U},
    {"BO_ 536870911 Frame: 255 ECU", 0x1FFFFFFFU, true, 255U},
    {"BO_ 2147483649 Frame: 8 ECU", 1U, true, 8U},
    {"BO_ 2684354559 Frame: 8 ECU", 0x1FFFFFFFU, true, 8U},
    {"  BO_\t256\tFrame :\t8\tECU  \r", 256U, false, 8U}
  };
  for (const auto &test : valid) {
    fixture.Write (std::string (test.line) + '\n');
    try {
      const auto database = DbcParser().ParseFile (fixture.path.string());
      check (database.frames.size() == 1U && database.frames[0].name == "Frame" &&
             database.frames[0].canId == test.id &&
             database.frames[0].isExtended == test.extended &&
             database.frames[0].dlc == test.length &&
             database.frames[0].transmitter == "ECU", test.line);
    } catch (const std::exception &error) { check (false, error.what()); }
  }
  const char *invalid[] = {
    "BO_ invalid", "BO_", "BO_ 1", "BO_ 1 : 8 ECU", "BO_ 1 Frame 8 ECU",
    "BO_ 1 Frame:", "BO_ 1 Frame: 8", "BO_ 1 Frame: 8 ECU extra",
    "BO_ 1 Two Names: 8 ECU", "BO_ -1 Frame: 8 ECU", "BO_ +1 Frame: 8 ECU",
    "BO_ 1x Frame: 8 ECU", "BO_ 0x123 Frame: 8 ECU", "BO_ 1.5 Frame: 8 ECU",
    "BO_ 4294967296 Frame: 8 ECU", "BO_ 999999999999999999999 Frame: 8 ECU",
    "BO_ 536870912 Frame: 8 ECU", "BO_ 1073741824 Frame: 8 ECU",
    "BO_ 2684354560 Frame: 8 ECU", "BO_ 4294967295 Frame: 8 ECU",
    "BO_ 1 Frame: -1 ECU", "BO_ 1 Frame: +8 ECU", "BO_ 1 Frame: 8x ECU",
    "BO_ 1 Frame: 8.5 ECU", "BO_ 1 Frame: 256 ECU",
    "BO_ 1 Frame: 4294967296 ECU", "BO_\tinvalid"
  };
  for (const auto *line : invalid) {
    fixture.Write (std::string ("VERSION \"test\"\n\n") + line + '\n');
    try {
      DbcParser().ParseFile (fixture.path.string());
      check (false, line);
    } catch (const std::runtime_error &error) {
      const std::string prefix = fixture.path.string() + ":3: ";
      check (std::string (error.what()).find (prefix) == 0U &&
             std::string (error.what()).size() > prefix.size(), line);
    }
  }
  fixture.Write (
    "BO_TX_BU_ 256 : ECU;\nBO_ 256 Frame: 8 ECU\n"
    " SG_ Speed : 0|16@1+ (0.5,1) [0|100] \"rpm\" ECU\n"
    "CM_ BO_ 256 \"Frame comment\";\nCM_ SG_ 256 Speed \"Signal comment\";\n"
    "BO_ 257 Second: 8 ECU\n");
  const auto database = DbcParser().ParseFile (fixture.path.string());
  check (database.frames.size() == 2U && database.frames[0].signals.size() == 1U &&
         database.frames[0].comment == "Frame comment" &&
         database.frames[0].signals[0].comment == "Signal comment", "Integration");
  fixture.Write ("\nSG_ Speed : invalid\n");
  try {
    DbcParser().ParseFile (fixture.path.string());
    check (false, "Signal error location");
  } catch (const std::runtime_error &error) {
    check (std::string (error.what()).find (fixture.path.string() + ":2: ") == 0U,
           "Signal error location");
  }
  if (failures != 0) return 1;
  std::cout << "All " << count << " parser cases passed.\n";
  return 0;
}