/*
  This file is part of Raul.
  Copyright 2007-2012 David Robillard <http://drobilla.net>

  Raul is free software: you can redistribute it and/or modify it under the
  terms of the GNU General Public License as published by the Free Software
  Foundation, either version 3 of the License, or any later version.

  Raul is distributed in the hope that it will be useful, but WITHOUT ANY
  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with Raul.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef RAUL_SYMBOL_HPP
#define RAUL_SYMBOL_HPP

#include <cctype>
#include <cstring>
#include <exception>
#include <iostream>
#include <string>

#include <glib.h>

namespace Raul {

/** A restricted string (C identifier, which is a component of a Path).
 *
 * A Symbol is a very restricted string suitable for use as an identifier.
 * It is a valid LV2 symbol, URI fragment, filename, OSC path fragment,
 * and identifier for most programming languages (including C).
 *
 * Valid characters are _, a-z, A-Z, 0-9, except the first character which
 * must not be 0-9.
 *
 * \ingroup raul
 */
class Symbol {
public:
	class BadSymbol : public std::exception {
	public:
		explicit BadSymbol(const std::string& symbol) : _symbol(symbol) {}
		~BadSymbol() throw() {}
		const char* what() const throw() { return _symbol.c_str(); }
	private:
		const std::string _symbol;
	};

	/** Construct a Symbol from an std::string.
	 *
	 * It is a fatal error to construct a Symbol from an invalid string,
	 * use is_valid first to check.
	 */
	explicit Symbol(const std::basic_string<char>& symbol) throw(BadSymbol)
		: _str(g_intern_string(symbol.c_str()))
	{
		if (!is_valid(symbol)) {
			throw BadSymbol(symbol);
		}
	}

	/** Construct a Symbol from a C string.
	 *
	 * It is a fatal error to construct a Symbol from an invalid string,
	 * use is_valid first to check.
	 */
	explicit Symbol(const char* csymbol) throw(BadSymbol)
		: _str(g_intern_string(csymbol))
	{
		if (!is_valid(csymbol)) {
			throw BadSymbol(csymbol);
		}
	}

	Symbol& operator=(const Symbol& other) {
		_str = other._str;
		return *this;
	}

	inline const char* c_str() const { return _str; }

	inline bool operator==(const Symbol& other) const {
		return _str == other._str;
	}

	inline bool operator!=(const Symbol& other) const {
		return _str != other._str;
	}

	inline bool operator<(const Symbol& other) const {
		return strcmp(_str, other._str) < 0;
	}

	static bool is_valid(const std::basic_string<char>& symbol);

	static Raul::Symbol symbolify(const std::basic_string<char>& str);

private:
	const char* _str;
};

} // namespace Raul

static inline std::ostream&
operator<<(std::ostream& os, const Raul::Symbol& symbol)
{
	return (os << symbol.c_str());
}

#endif // RAUL_SYMBOL_HPP