// Copyright(C) 1999-2021 National Technology & Engineering Solutions
// of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
// NTESS, the U.S. Government retains certain rights in this software.
//
// See packages/seacas/LICENSE for details

#include <fstream>
#include <iostream>

#include "apr_symrec.h"
#include "aprepro.h"

// This function is used below in the example showing how an
// application can add its own functions to an aprepro instance.
double succ(double i) { return ++i; }

int main(int argc, char *argv[])
{
  bool readfile = false;

  std::string output_file;

  SEAMS::Aprepro aprepro;

  // EXAMPLE: Add a function to aprepro...
  SEAMS::symrec *ptr   = aprepro.putsym("succ", SEAMS::Aprepro::SYMBOL_TYPE::FUNCTION, false);
  ptr->value.fnctptr_d = succ;
  ptr->info            = "Return the successor to d";
  ptr->syntax          = "succ(d)";

  // EXAMPLE: Add a couple variables...
  aprepro.add_variable("Greg", "Is the author of this code", true); // Make it immutable
  aprepro.add_variable("BirthYear", 1958);

  for (int ai = 1; ai < argc; ++ai) {
    std::string arg = argv[ai];
    if (arg == "-o") {
      output_file = argv[++ai];
    }
    if (arg == "-i") {
      // Read from cin and echo each line to cout All results will
      // also be stored in Aprepro::parsing_results() stream if needed
      // at end of file.
      aprepro.ap_options.interactive = true;
      bool result                    = aprepro.parse_stream(std::cin, "standard input");
      if (result) {
        if (!output_file.empty()) {
          std::ofstream ofile(output_file);
          ofile << aprepro.parsing_results().str();
        }
        else {
          std::cout << aprepro.parsing_results().str();
        }
      }
    }
    else if (arg[0] == '-') {
      aprepro.set_option(argv[ai]);
    }
    else {
      // Read and parse a file.  The entire file will be parsed and
      // then the output can be obtained in an std::ostringstream via
      // Aprepro::parsing_results()
      std::fstream infile(argv[ai]);
      if (!infile.good()) {
        std::cerr << "APREPRO: Could not open file: " << argv[ai] << '\n';
        return 0;
      }

      bool result = aprepro.parse_stream(infile, argv[ai]);
      if (result) {
        if (!output_file.empty()) {
          std::ofstream ofile(output_file);
          ofile << aprepro.parsing_results().str();
        }
        else {
          std::cout << aprepro.parsing_results().str();
        }
      }

      readfile = true;
    }
  }
  if (readfile) {
    std::cerr << "Aprepro: There were " << aprepro.get_error_count()
              << " errors detected during parsing.\n";
    return 0;
  }

  // Read and parse a string's worth of data at a time.
  // Cannot use looping/ifs/... with this method.
  std::string line, tmp;
  while (std::cout << "\nexpression: " && std::getline(std::cin, tmp) && !tmp.empty()) {

    line += tmp;

    if (*tmp.rbegin() == '\\') {
      line.erase(line.length() - 1);
      continue;
    }

    line += "\n";

    bool result = aprepro.parse_string_interactive(line);

    if (result) {
      std::string res_str = aprepro.parsing_results().str();
      std::cout << "         : " << res_str;

      // Example showing how to get the substitution history for the current line.
      if (aprepro.ap_options.keep_history) {
        std::vector<SEAMS::history_data> hist = aprepro.get_history();
        for (const auto &curr_history : hist) {

          std::cout << curr_history.original << " was substituted with "
                    << curr_history.substitution << " at index " << curr_history.index << '\n';
        }

        aprepro.clear_history();
      }
    }

    aprepro.clear_results();

    line.clear();
  }
  std::cerr << "Aprepro: There were " << aprepro.get_error_count()
            << " errors detected during parsing.\n";
}