/*
 * options.h -- parse Unix command line options
 *
 * Copyright (c) 2015 David Demelier <markand@malikania.fr>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _OPTION_PARSER_H_
#define _OPTION_PARSER_H_

#include <exception>
#include <map>
#include <string>
#include <utility>
#include <vector>

namespace irccd {

/**
 * Namespace for options parsing.
 */
namespace parser {

/**
 * @class InvalidOption
 * @brief This exception is thrown when an invalid option has been found.
 */
class InvalidOption : public std::exception {
private:
	std::string message;

public:
	/**
	 * The invalid option given.
	 */
	std::string argument;

	/**
	 * Construct the exception.
	 *
	 * @param arg the argument missing
	 */
	inline InvalidOption(std::string arg)
		: argument(std::move(arg))
	{
		message = std::string("invalid option: ") + argument;
	}

	/**
	 * Get the error message.
	 *
	 * @return the error message
	 */
	const char *what() const noexcept override
	{
		return message.c_str();
	}
};

/**
 * @class MissingValue
 * @brief This exception is thrown when an option requires a value and no value has been given
 */
class MissingValue : public std::exception {
private:
	std::string message;

public:
	/**
	 * The argument that requires a value.
	 */
	std::string argument;

	/**
	 * Construct the exception.
	 *
	 * @param arg the argument that requires a value
	 */
	inline MissingValue(std::string arg)
		: argument(std::move(arg))
	{
		message = std::string("missing argument for: ") + argument;
	}

	/**
	 * Get the error message.
	 *
	 * @return the error message
	 */
	const char *what() const noexcept override
	{
		return message.c_str();
	}
};

/**
 * Packed multimap of options.
 */
using Result = std::multimap<std::string, std::string>;

/**
 * Define the allowed options.
 */
using Options = std::map<std::string, bool>;

/**
 * Extract the command line options and return a result.
 *
 * @param args the arguments
 * @param definition
 * @warning the arguments vector is modified in place to remove parsed options
 * @throw MissingValue
 * @throw InvalidOption
 */
Result read(std::vector<std::string> &args, const Options &definition);

/**
 * Overloaded function for usage with main() arguments.
 *
 * @param argc the number of arguments
 * @param argv the argument vector
 * @param definition
 * @note don't forget to remove the first argv[0] argument
 * @warning the argc and argv are modified in place to remove parsed options
 * @throw MissingValue
 * @throw InvalidOption
 */
Result read(int &argc, char **&argv, const Options &definition);

} // !parser

} // !irccd

#endif // !_OPTION_PARSER_H_