#include <string>
#include <source_location>
#include <fmt/core.h>

using namespace std;

namespace dbc {
  class Error {
    public:
      const string message;
      Error(string m) : message{m} {}
      Error(const char *m) : message{m} {}
  };

  class CheckError : public Error {};

  class SentinelError : public Error {};
  class PreCondError : public Error {};
  class PostCondError : public Error {};

  void log(const string &message, std::source_location loc = std::source_location::current()) {
    fmt::print("[{}:{}:{}] {}\n", loc.file_name(), loc.function_name(), loc.line(), message);
  }

  void sentinel(const string &message, std::source_location loc = std::source_location::current()) {
    string err = fmt::format("[SENTINEL! {}:{}:{}:{}] {}\n",
          loc.file_name(), loc.function_name(),
          loc.line(), loc.column(), message);
    throw SentinelError{err};
  }

  void pre(const string &message, std::function<bool()> tester, std::source_location loc = std::source_location::current()) {
    if(!tester()) {
      string err = fmt::format("[PRE! {}:{}:{}:{}] {}\n",
          loc.file_name(), loc.function_name(),
          loc.line(), loc.column(), message);
      throw PreCondError{err};
    }
  }

  void post(const string &message, std::function<bool()> tester, std::source_location loc = std::source_location::current()) {
    if(!tester()) {
      string err = fmt::format("[POST! {}:{}:{}:{}] {}\n",
          loc.file_name(), loc.function_name(),
          loc.line(), loc.column(), message);
      throw PostCondError{err};
    }
  }

  void check(bool test, const string &message, std::source_location loc = std::source_location::current()) {

    if(!test) {
      string err = fmt::format("[CHECK! {}:{}:{}:{}] {}\n",
          loc.file_name(), loc.function_name(),
          loc.line(), loc.column(), message);
      throw CheckError{err};
    }
  }
}