/* The copyright in this software is being made available under the BSD
 * License, included below. This software may be subject to other third party
 * and contributor rights, including patent rights, and no such rights are
 * granted under this license.
 *
 * Copyright (c) 2010-2023, ITU/ISO/IEC
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  * Neither the name of the ITU/ISO/IEC nor the names of its contributors may
 *    be used to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include <iostream>
#include <sstream>
#include <string>
#include <list>
#include <map>
#include <vector>
#include <optional>
#include <cstdint>

template<class T> inline std::istream& operator>>(std::istream& in, std::optional<T>& value)
{
  in >> std::ws;
  if (in.eof())
  {
    value = std::nullopt;
  }
  else
  {
    T tmp;
    in >> tmp;
    value = tmp;
  }
  return in;
}

template <class T>
struct SMultiValueInput
{
  static_assert(!std::is_same<T, uint8_t>::value, "SMultiValueInput<uint8_t> is not supported");
  static_assert(!std::is_same<T, int8_t>::value, "SMultiValueInput<int8_t> is not supported");
  const T              minValIncl;
  const T              maxValIncl;
  const std::size_t    minNumValuesIncl;
  const std::size_t    maxNumValuesIncl; // Use 0 for unlimited
  std::vector<T> values;
  SMultiValueInput() : minValIncl(0), maxValIncl(0), minNumValuesIncl(0), maxNumValuesIncl(0), values() { }
  SMultiValueInput(std::vector<T> &defaults) : minValIncl(0), maxValIncl(0), minNumValuesIncl(0), maxNumValuesIncl(0), values(defaults) { }
  SMultiValueInput(const T &minValue, const T &maxValue, std::size_t minNumberValues = 0, std::size_t maxNumberValues = 0)
    : minValIncl(minValue), maxValIncl(maxValue), minNumValuesIncl(minNumberValues), maxNumValuesIncl(maxNumberValues), values() { }
  SMultiValueInput(const T &minValue, const T &maxValue, std::size_t minNumberValues, std::size_t maxNumberValues, const T* defValues, const uint32_t numDefValues)
    : minValIncl(minValue), maxValIncl(maxValue), minNumValuesIncl(minNumberValues), maxNumValuesIncl(maxNumberValues), values(defValues, defValues + numDefValues) { }
  SMultiValueInput<T> &operator=(const std::vector<T> &userValues) { values = userValues; return *this; }
  SMultiValueInput<T> &operator=(const SMultiValueInput<T> &userValues) { values = userValues.values; return *this; }

  T readValue(const char *&pStr, bool &bSuccess);

  std::istream &readValues(std::istream &in);
};

namespace ProgramOptionsLite
{
struct Options;

struct ParseFailure : public std::exception
{
  ParseFailure(std::string arg0, std::string val0) throw() : arg(arg0), val(val0) {}

  ~ParseFailure() throw(){};

  std::string arg;
  std::string val;

  const char* what() const throw() { return "Option Parse Failure"; }
};

struct ErrorReporter
{
  ErrorReporter() : is_errored(0) {}
  virtual ~ErrorReporter() {}
  virtual std::ostream& error(const std::string& where);
  virtual std::ostream& warn(const std::string& where);
  bool                  is_errored;
};

extern ErrorReporter default_error_reporter;

struct SilentReporter : ErrorReporter
{
  SilentReporter() {}
  virtual ~SilentReporter() {}
  virtual std::ostream& error(const std::string& where) { return dest; }
  virtual std::ostream& warn(const std::string& where) { return dest; }
  std::stringstream     dest;
};

void                   doHelp(std::ostream& out, Options& opts, unsigned columns = 80);
std::list<const char*> scanArgv(Options& opts, unsigned argc, const char* argv[],
                                ErrorReporter& error_reporter = default_error_reporter);
void                   setDefaults(Options& opts);
void                   parseConfigFile(Options& opts, const std::string& filename,
                                       ErrorReporter& error_reporter = default_error_reporter);

/** OptionBase: Virtual base class for storing information relating to a
 * specific option This base class describes common elements.  Type specific
 * information should be stored in a derived class. */
struct OptionBase
{
  OptionBase(const std::string& name, const std::string& desc) : opt_string(name), opt_desc(desc){};

  virtual ~OptionBase() {}

  /* parse argument arg, to obtain a value for the option */
  virtual void parse(const std::string& arg, ErrorReporter&) = 0;
  /* set the argument to the default value */
  virtual void setDefault()                                  = 0;

  std::string opt_string;
  std::string opt_desc;
};

/** Type specific option storage */
template<typename T> struct Option : public OptionBase
{
  Option(const std::string& name, T& storage, T default_val, const std::string& desc)
    : OptionBase(name, desc), opt_storage(storage), opt_default_val(default_val)
  {}

  void parse(const std::string& arg, ErrorReporter&);

  void setDefault() { opt_storage = opt_default_val; }

  T& opt_storage;
  T  opt_default_val;
};

/* Generic parsing */
template<typename T> inline void Option<T>::parse(const std::string& arg, ErrorReporter&)
{
  std::istringstream arg_ss(arg, std::istringstream::in);
  arg_ss.exceptions(std::ios::failbit);
  try
  {
    arg_ss >> opt_storage;
  }
  catch (...)
  {
    throw ParseFailure(opt_string, arg);
  }
}

/* string parsing is specialized -- copy the whole string, not just the
 * first word */
template<> inline void Option<std::string>::parse(const std::string& arg, ErrorReporter&) { opt_storage = arg; }

/** Option class for argument handling using a user provided function */
struct OptionFunc : public OptionBase
{
  typedef void(Func)(Options&, const std::string&, ErrorReporter&);

  OptionFunc(const std::string& name, Options& parent_, Func* func_, const std::string& desc)
    : OptionBase(name, desc), parent(parent_), func(func_)
  {}

  void parse(const std::string& arg, ErrorReporter& error_reporter) { func(parent, arg, error_reporter); }

  void setDefault() { return; }

private:
  Options& parent;
  Func*    func;
};

class OptionSpecific;
struct Options
{
  ~Options();

  OptionSpecific addOptions();

  struct Names
  {
    Names() : opt(0){};
    ~Names()
    {
      if (opt)
      {
        delete opt;
      }
    }
    std::list<std::string> opt_long;
    std::list<std::string> opt_short;
    std::list<std::string> opt_prefix;
    OptionBase*            opt;
  };

  void addOption(OptionBase* opt);

  typedef std::list<Names*> NamesPtrList;
  NamesPtrList              opt_list;

  typedef std::map<std::string, NamesPtrList> NamesMap;
  NamesMap                                    opt_long_map;
  NamesMap                                    opt_short_map;
  NamesMap                                    opt_prefix_map;
};

/* Class with templated overloaded operator(), for use by Options::addOptions() */
class OptionSpecific
{
public:
  OptionSpecific(Options& parent_) : parent(parent_) {}

  /**
   * Add option described by name to the parent Options list,
   *   with storage for the option's value
   *   with default_val as the default value
   *   with desc as an optional help description
   */
  template<typename T>
  OptionSpecific& operator()(const std::string& name, T& storage, T default_val, const std::string& desc = "")
  {
    parent.addOption(new Option<T>(name, storage, default_val, desc));
    return *this;
  }
  template<typename T> OptionSpecific& operator()(const std::string& name, T* storage, T default_val, unsigned uiMaxNum,
                                                  const std::string& desc = "")
  {
    std::string cNameBuffer;
    std::string cDescriptionBuffer;

    for (unsigned int k = 0; k < uiMaxNum; k++)
    {
      // it needs to be reset when extra digit is added, e.g. number 10 and above
      cNameBuffer.resize(name.size() + 10);
      cDescriptionBuffer.resize(desc.size() + 10);

      // isn't there are sprintf function for string??
      snprintf((char*) cNameBuffer.c_str(), cNameBuffer.size(), name.c_str(), k, k);
      snprintf((char*) cDescriptionBuffer.c_str(), cDescriptionBuffer.size(), desc.c_str(), k, k);

      size_t pos = cNameBuffer.find_first_of('\0');
      if (pos != std::string::npos)
      {
        cNameBuffer.resize(pos);
      }

      parent.addOption(new Option<T>(cNameBuffer, (storage[k]), default_val, cDescriptionBuffer));
    }

    return *this;
  }

  template<typename T> OptionSpecific& operator()(const std::string& name, T** storage, T default_val,
                                                  unsigned uiMaxNum, const std::string& desc = "")
  {
    std::string cNameBuffer;
    std::string cDescriptionBuffer;

    for (unsigned int k = 0; k < uiMaxNum; k++)
    {
      // it needs to be reset when extra digit is added, e.g. number 10 and above
      cNameBuffer.resize(name.size() + 10);
      cDescriptionBuffer.resize(desc.size() + 10);

      // isn't there are sprintf function for string??
      snprintf((char*) cNameBuffer.c_str(), cNameBuffer.size(), name.c_str(), k, k);
      snprintf((char*) cDescriptionBuffer.c_str(), cDescriptionBuffer.size(), desc.c_str(), k, k);

      size_t pos = cNameBuffer.find_first_of('\0');
      if (pos != std::string::npos)
        cNameBuffer.resize(pos);

      parent.addOption(new Option<T>(cNameBuffer, *(storage[k]), default_val, cDescriptionBuffer));
    }

    return *this;
  }
  /**
   * Add option described by name to the parent Options list,
   *   with desc as an optional help description
   * instead of storing the value somewhere, a function of type
   * OptionFunc::Func is called.  It is upto this function to correctly
   * handle evaluating the option's value.
   */
  OptionSpecific& operator()(const std::string& name, OptionFunc::Func* func, const std::string& desc = "")
  {
    parent.addOption(new OptionFunc(name, parent, func, desc));
    return *this;
  }

private:
  Options& parent;
};

}   // namespace ProgramOptionsLite
