// 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

/* S Manoharan. Advanced Computer Research Institute. Lyon. France */
#include <GetLongOpt.h>
#include <cstring>
#include <fmt/color.h>
#include <fmt/ostream.h>
#include <sstream>

/** \brief Create an empty options database.
 *
 * \param optmark The command line symbol designating options.
 */
GetLongOption::GetLongOption(const char optmark) : optmarker(optmark)
{
  ustring = "[valid options and arguments]";
}

/** \brief Frees dynamically allocated memory.
 *
 *  Frees memory for the private struct variables representing the options.
 */
GetLongOption::~GetLongOption()
{
  Cell *t = table;

  while (t != nullptr) {
    Cell *tmp = t;
    t         = t->next;
    delete tmp;
  }
}

/** \brief Extract the base file name from a full path.
 *
 *  Finds the last instance of the '/' character and
 *  extracts the part of the string that follows.
 *
 *  \param[in] pathname The full path.
 *  \return The base file name.
 */
char *GetLongOption::basename(char *const pathname)
{
  char *s = strrchr(pathname, '/');
  if (s == nullptr) {
    s = pathname;
  }
  else {
    ++s;
  }
  return s;
}

/** \brief Enroll a command line option into the database.
 *
 *  Dynamically allocates memory for the option, sets its name
 *  type, description, value, and default value, and links it
 *  to the preceding option.
 *
 * \param[in] opt The long option name.
 * \param[in] t The option type.
 * \param[in] desc A short description of the option.
 * \param[in] val The option value.
 * \param[in] optval The default value.
 * \returns 1 if successful, 0 if unsuccessful.
 */
bool GetLongOption::enroll(const char *const opt, const OptType t, const char *const desc,
                           const char *const val, const char *const optval, bool extra_line)
{
  if (options_parsed) {
    return false;
  }

  auto *c        = new Cell;
  c->option      = opt;
  c->type        = t;
  c->description = desc != nullptr ? desc : "no description available";
  c->value       = val;
  c->opt_value   = optval;
  c->next        = nullptr;
  c->extra_line  = extra_line;

  if (last == nullptr) {
    table = last = c;
  }
  else {
    last->next = c;
    last       = c;
  }

  return true;
}

const char *GetLongOption::program_name() const { return pname == nullptr ? "[UNSET]" : pname; }

/** \brief Get a command line option object.
 *
 *  \param[in] opt The option name.
 *  \returns The option object.
 */
const char *GetLongOption::retrieve(const char *const opt) const
{
  Cell *t;
  for (t = table; t != nullptr; t = t->next) {
    if (strcmp(opt, t->option) == 0) {
      return t->value;
    }
  }
  fmt::print(stderr, "GetLongOption::retrieve - unenrolled option {}{}\n", optmarker, opt);
  return nullptr;
}

/** \brief parse command line arguments
 *
 *  Set the values of options in the option table based on
 *  the given command line arguments.
 *
 *  \param[in] argc Number of command line arguments passed in from main(int argc, char *argv[]).
 *  \param[in] argv Command line arguments passed in from main(int argc, char *argv[]).
 *  \returns Number of options processed, or -1 on failure.
 *
 */
int GetLongOption::parse(int argc, char *const *argv)
{
  int my_optind = 1;

  std::ostringstream multiple_match;

  pname          = basename(*argv);
  options_parsed = true;
  if (argc-- <= 1) {
    return my_optind;
  }

  while (argc >= 1) {
    char *token = *++argv;
    --argc;

    // '--' signifies end of options if followed by space
    if (token[0] != optmarker || (token[1] == optmarker && strlen(token) == 2)) {
      break; /* end of options */
    }

    ++my_optind;
    char *tmptoken = ++token;
    if (token[0] == optmarker) { // Handle a double '--'
      tmptoken = ++token;
    }

    while (*tmptoken != '\0' && *tmptoken != '=') {
      ++tmptoken;
    }
    /* (tmptoken - token) is now equal to the command line option
       length. */

    Cell *t;
    enum { NoMatch, ExactMatch, PartialMatch, MultipleMatch } matchStatus = NoMatch;

    Cell *pc = nullptr; // pointer to the partially-matched cell
    for (t = table; t != nullptr; t = t->next) {
      if (strncmp(t->option, token, (tmptoken - token)) == 0) {
        if (static_cast<int>(strlen(t->option)) == (tmptoken - token)) {
          /* an exact match found */
          int stat = setcell(t, tmptoken, *(argv + 1), pname);
          if (stat == -1) {
            return -1;
          }
          if (stat == 1) {
            ++argv;
            --argc;
            ++my_optind;
          }
          matchStatus = ExactMatch;
          break;
        }
        else {
          /* partial match found */
          if (pc == nullptr) {
            matchStatus = PartialMatch;
            pc          = t;
          }
          else {
            // Multiple partial matches...Print warning
            if (matchStatus == PartialMatch) {
              // First time, print the message header and the first
              // matched duplicate...
              fmt::print(multiple_match, "ERROR: {}: Multiple matches found for option '{}{}'.\n",
                         pname, optmarker, strtok(token, "= "));
              fmt::print(multiple_match, "\t{}{}: {}\n", optmarker, pc->option, pc->description);
            }
            fmt::print(multiple_match, "\t{}{}:{}\n", optmarker, t->option, t->description);
            matchStatus = MultipleMatch;
          }
        }
      } /* end if */
    }   /* end for */

    if (matchStatus == PartialMatch) {
      int stat = setcell(pc, tmptoken, *(argv + 1), pname);
      if (stat == -1) {
        return -1;
      }
      if (stat == 1) {
        ++argv;
        --argc;
        ++my_optind;
      }
    }
    else if (matchStatus == NoMatch) {
      fmt::print(stderr, "{}: unrecognized option {}{}\n", pname, optmarker, strtok(token, "= "));
      return -1; /* no match */
    }
    else if (matchStatus == MultipleMatch) {
      std::cerr << multiple_match.str();
      return -1; /* no match */
    }

  } /* end while */
  return my_optind;
}

/** \brief parse an argument string.
 *
 *  Set the values of options in the option table based on
 *  the given option string.
 *
 *  \param[in] str The option string.
 *  \param[in] p A string to be used in error reporting
 *  \returns 1 if successful, or -1 otherwise.
 *
 */
int GetLongOption::parse(char *const str, char *const p)
{
  options_parsed    = true;
  char       *token = strtok(str, " \t");
  const char *name  = p != nullptr ? p : "GetLongOption";

  while (token != nullptr) {
    if (token[0] != optmarker || (token[1] == optmarker && strlen(token) == 2)) {
      fmt::print(stderr, "{}: nonoptions not allowed\n", name);
      return -1; /* end of options */
    }

    char *ladtoken = nullptr; /* lookahead token */
    char *tmptoken = ++token;
    while (*tmptoken != '\0' && *tmptoken != '=') {
      ++tmptoken;
    }
    /* (tmptoken - token) is now equal to the command line option
       length. */

    Cell *t;
    enum { NoMatch, ExactMatch, PartialMatch } matchStatus = NoMatch;
    Cell *pc = nullptr; // pointer to the partially-matched cell
    for (t = table; t != nullptr; t = t->next) {
      if (strncmp(t->option, token, (tmptoken - token)) == 0) {
        if (static_cast<int>(strlen(t->option)) == (tmptoken - token)) {
          /* an exact match found */
          ladtoken = strtok(nullptr, " \t");
          int stat = setcell(t, tmptoken, ladtoken, name);
          if (stat == -1) {
            return -1;
          }
          if (stat == 1) {
            ladtoken = nullptr;
          }
          matchStatus = ExactMatch;
          break;
        }
        else {
          /* partial match found */
          matchStatus = PartialMatch;
          pc          = t;
        }
      } /* end if */
    }   /* end for */

    if (matchStatus == PartialMatch) {
      ladtoken = strtok(nullptr, " \t");
      int stat = setcell(pc, tmptoken, ladtoken, name);
      if (stat == -1) {
        return -1;
      }
      if (stat == 1) {
        ladtoken = nullptr;
      }
    }
    else if (matchStatus == NoMatch) {
      fmt::print(stderr, "{}: unrecognized option {}{}\n", name, optmarker, strtok(token, "= "));
      return -1; /* no match */
    }

    token = ladtoken != nullptr ? ladtoken : strtok(nullptr, " \t");
  } /* end while */

  return 1;
}

/* ----------------------------------------------------------------
   GetLongOption::setcell returns
   -1 if there was an error
   0  if the nexttoken was not consumed
   1  if the nexttoken was consumed
   ------------------------------------------------------------------- */

int GetLongOption::setcell(Cell *c, char *valtoken, char *nexttoken, const char *name)
{
  if (c == nullptr) {
    return -1;
  }

  switch (c->type) {
  case GetLongOption::NoValue:
    if (*valtoken == '=') {
      fmt::print(stderr, "{}: unsolicited value for flag {}{}\n", name, optmarker, c->option);
      return -1; /* unsolicited value specification */
    }
    // Set to a non-zero value.  Used to be "(char*) ~0", but that
    // gives out-of-range warnings on some systems...
    c->value = (char *)1;
    return 0;
  case GetLongOption::OptionalValue:
    if (*valtoken == '=') {
      c->value = ++valtoken;
      return 0;
    }
    else {
      if (nexttoken != nullptr && nexttoken[0] != optmarker) {
        c->value = nexttoken;
        return 1;
      }
      c->value = c->opt_value;
      return 0;
    }
  case GetLongOption::MandatoryValue:
    if (*valtoken == '=') {
      c->value = ++valtoken;
      return 0;
    }
    else {
      if (nexttoken != nullptr) {
        c->value = nexttoken;
        return 1;
      }
      fmt::print(stderr, "{}: mandatory value for {}{} not specified\n", name, optmarker,
                 c->option);
      return -1; /* mandatory value not specified */
    }
  default: break;
  }
  return -1;
}

/** \brief Print the program usage string.
 *
 *  \param[in] outfile The output stream to which the usage string is printed.
 */
void GetLongOption::usage(std::ostream &outfile) const
{
  // The API of `usage` specifies an `ostream` for the output location. However,
  // the fmt::print color options do not work with an ostream and instead
  // want a FILE*.  To give formatting in the usage message, we convert the
  // ostream to a FILE* if it is std::cout or std::cerr; otherwise use the old
  // non-formatted version...
  FILE *out = nullptr;
  if (&outfile == &std::cout) {
    out = stdout;
  }
  else if (&outfile == &std::cerr) {
    out = stderr;
  }

  if (out != nullptr) {
    fmt::print(out, fmt::emphasis::bold, "\nusage: {} {}\n", pname, ustring);
    for (Cell *t = table; t != nullptr; t = t->next) {
      fmt::print(out, fmt::emphasis::bold, "\t{}{}", optmarker, t->option);
      if (t->type == GetLongOption::MandatoryValue) {
        fmt::print(out, fmt::emphasis::italic | fmt::emphasis::bold, " <$val>");
      }
      else if (t->type == GetLongOption::OptionalValue) {
        fmt::print(out, fmt::emphasis::italic | fmt::emphasis::bold, " [$val]");
      }
      fmt::print(out, " ({})\n", t->description);
      if (t->extra_line) {
        fmt::print(out, "\n");
      }
    }
  }
  else {
    fmt::print(outfile, "\nusage: {} {}\n", pname, ustring);
    for (Cell *t = table; t != nullptr; t = t->next) {
      fmt::print(outfile, "\t{}{}", optmarker, t->option);
      if (t->type == GetLongOption::MandatoryValue) {
        fmt::print(outfile, " <$val>");
      }
      else if (t->type == GetLongOption::OptionalValue) {
        fmt::print(outfile, " [$val]");
      }
      fmt::print(outfile, " ({})\n", t->description);
      if (t->extra_line) {
        fmt::print(outfile, "\n");
      }
    }
    outfile.flush();
  }
}