#ifndef CSVFILE_HPP
#define CSVFILE_HPP
#include <fstream>
#include <iostream>
#include <sstream>
#include <string>

class csvFile;

inline static csvFile &endrow(csvFile &file);
inline static csvFile &flush(csvFile &file);

class csvFile {
  std::ofstream fs_;
  bool is_first_;
  const std::string separator_;
  const std::string escape_seq_;
  const std::string special_chars_;

public:
  csvFile(const std::string filename, const bool &overwrite,
          const std::string separator = ",")
      : fs_(), is_first_(true), separator_(separator), escape_seq_("\""),
        special_chars_("\"") {
    fs_.exceptions(std::ios::failbit | std::ios::badbit);
    if (filename.empty()) {
      fs_.copyfmt(std::cout);
      fs_.clear(std::cout.rdstate());
      fs_.basic_ios<char>::rdbuf(std::cout.rdbuf());
    } else {
      if (!std::filesystem::exists(
              std::filesystem::path("../OptimizationResults")
                  .append("statistics.csv"))) {
        std::ofstream outfile(std::filesystem::path("../OptimizationResults")
                                  .append("statistics.csv")
                                  .string());
        outfile.close();
      }
      overwrite ? fs_.open(filename, std::ios::trunc)
                : fs_.open(filename, std::ios::app);
    }
  }

  ~csvFile() {
    flush();
    fs_.close();
  }

  void flush() { fs_.flush(); }

  void endrow() {
    fs_ << std::endl;
    is_first_ = true;
  }

  csvFile &operator<<(csvFile &(*val)(csvFile &)) { return val(*this); }

  csvFile &operator<<(const char *val) { return write(escape(val)); }

  csvFile &operator<<(const std::string &val) { return write(escape(val)); }

  template <typename T> csvFile &operator<<(const T &val) { return write(val); }

private:
  template <typename T> csvFile &write(const T &val) {
    if (!is_first_) {
      fs_ << separator_;
    } else {
      is_first_ = false;
    }
    fs_ << val;
    return *this;
  }

  std::string escape(const std::string &val) {
    std::ostringstream result;
    result << '"';
    std::string::size_type to, from = 0u, len = val.length();
    while (from < len && std::string::npos !=
                             (to = val.find_first_of(special_chars_, from))) {
      result << val.substr(from, to - from) << escape_seq_ << val[to];
      from = to + 1;
    }
    result << val.substr(from) << '"';
    return result.str();
  }
};

inline static csvFile &endrow(csvFile &file) {
  file.endrow();
  return file;
}

inline static csvFile &flush(csvFile &file) {
  file.flush();
  return file;
}

#endif // CSVFILE_HPP