//
// VMime library (http://www.vmime.org)
// Copyright (C) 2002 Vincent Richard <vincent@vmime.org>
//
// This program 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 (at your option) any later version.
//
// This program 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 this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// Linking this library statically or dynamically with other modules is making
// a combined work based on this library.  Thus, the terms and conditions of
// the GNU General Public License cover the whole combination.
//

#ifndef VMIME_WORDENCODER_HPP_INCLUDED
#define VMIME_WORDENCODER_HPP_INCLUDED


#include "vmime/charset.hpp"


namespace vmime {


namespace utility {
namespace encoder {

class encoder;

} // encoder
} // utility


/** Encodes words according to RFC-2047.
  */
class VMIME_EXPORT wordEncoder {

public:

	/** Available encodings for RFC-2047. */
	enum Encoding {
		ENCODING_AUTO,
		ENCODING_QP,
		ENCODING_B64
	};


	wordEncoder(
		const string& buffer,
		const charset& charset,
		const Encoding encoding = ENCODING_AUTO
	);


	/** Return the next chunk in the word.
	  *
	  * @param maxLength maximal length of the chunk
	  * @return next chunk, of maximal length 'maxLength' if possible
	  */
	const string getNextChunk(const size_t maxLength);

	/** Return the encoding used.
	  *
	  * @return encoding
	  */
	Encoding getEncoding() const;

	/** Test whether RFC-2047 encoding is needed.
	  *
	  * @param ctx generation context
	  * @param buffer buffer to analyze
	  * @param charset charset of the buffer
	  * @param lang language code, in the format specified by RFC-1766
	  * @return true if encoding is needed, false otherwise.
	  */
	static bool isEncodingNeeded(
		const generationContext& ctx,
		const string& buffer,
		const charset& charset,
		const string& lang
	);

	/** Guess the best RFC-2047 encoding to use for the specified buffer.
	  *
	  * @param buffer buffer to analyze
	  * @param charset charset of the buffer
	  * @return RFC-2047 encoding
	  */
	static Encoding guessBestEncoding(const string& buffer, const charset& charset);

private:

	string m_buffer;
	size_t m_pos;
	size_t m_length;

	bool m_simple;

	charset m_charset;
	Encoding m_encoding;

	shared_ptr <utility::encoder::encoder> m_encoder;
};


} // vmime


#endif // VMIME_WORDENCODER_HPP_INCLUDED