/*
 * This file is a part of PikoTools
 * and is distributed under the (new) BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2010-2021, Tomasz Sowa
 * 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 Tomasz Sowa nor the names of contributors to this
 *    project 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 OWNER 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.
 */

#ifndef headerfile_picotools_utf8_utf8
#define headerfile_picotools_utf8_utf8

#include <string>
#include "textstream/stream.h"


namespace pt
{

/*!
	UTF-8, a transformation format of ISO 10646
	http://tools.ietf.org/html/rfc3629

	when wchar_t is 4 bytes length we use UTF-32
	when wchar_t is 2 bytes length we use UTF-16 (with surrogate pairs)

	UTF-16
	http://www.ietf.org/rfc/rfc2781.txt
*/



/*!
	returns true if 'c' is a correct unicode character

	RENAMEME to is_correct_unicode_char
*/
bool utf8_check_range(int c);


/*!
	returns true if 'c' is a correct unicode character

	this method is used when reading from an utf8 string
	how_many_chars - means how many characters from utf8 string were read
*/
bool utf8_check_range(int c, int how_many_bytes);



/*
 * returns true if 'c' is a characters from the surrogate range
 * (c>=0xD800 && c<=0xDFFF)
 *
 */
bool is_surrogate_char(int c);



/*
 * returns true if 'c' is a first character from the surrogate pair
 * (c>=0xD800 && c<=0xDBFF)
 */
bool is_first_surrogate_char(int c);


/*
 * returns true if 'c' is a second character from the surrogate pair
 * (c>=0xDC00 && c<=0xDFFF)
 */
bool is_second_surrogate_char(int c);


/*
 * returns a code point from two surrogate pair characters
 */
bool surrogate_pair_to_int(int c1, int c2, int & z);



/*
 *
 *
 *
 * convertions from UTF-8
 *
 *
 *
 */

/*!
	converting one character from UTF-8 to an int
*/
size_t utf8_to_int(const char * utf8, size_t utf8_len, int & res, bool & correct);
size_t utf8_to_int(const char * utf8,                  int & res, bool & correct);
size_t utf8_to_int(const std::string & utf8,           int & res, bool & correct);
size_t utf8_to_int(std::istream & utf8,                int & res, bool & correct);
size_t utf8_to_int(const Stream & utf8, size_t stream_index, int & res, bool & correct);


/*!
	converting one character from int to wide stream
*/
template<typename StreamType>
void int_to_wide(int c, StreamType & res);



/*!
	converting UTF-8 string to a wide string
*/
bool utf8_to_wide(const char * utf8, size_t utf8_len, std::wstring & res, bool clear = true, int mode = 1);
bool utf8_to_wide(const char * utf8,                  std::wstring & res, bool clear = true, int mode = 1);
bool utf8_to_wide(const std::string & utf8,           std::wstring & res, bool clear = true, int mode = 1);
bool utf8_to_wide(std::istream & utf8,                std::wstring & res, bool clear = true, int mode = 1);

template<typename StreamType>
bool utf8_to_wide(const char * utf8, size_t utf8_len, StreamType & res, bool clear = true, int mode = 1); // need to be tested

template<typename StreamType>
bool utf8_to_wide(const char * utf8, StreamType & res, bool clear = true, int mode = 1); // need to be tested

template<typename StreamType>
bool utf8_to_wide(const std::string & utf8, StreamType & res, bool clear = true, int mode = 1); // need to be tested

template<typename StreamType>
bool utf8_to_wide(std::istream & utf8, StreamType & res, bool clear = true, int mode = 1); // need to be tested

template<typename StreamType>
bool utf8_to_wide(const Stream & stream, StreamType & res, bool clear = true, int mode = 1);


/*
 *
 *
 *
 * convertions to UTF-8
 *
 *
 *
 */


/*!
	converting one int character to UTF-8
*/
size_t int_to_utf8(int z, char * utf8, size_t utf8_max_len);
size_t int_to_utf8(int z, std::string & utf8, bool clear = true);

template<typename StreamType>
size_t int_to_utf8(int z, StreamType & utf8);



/*!
	converting a wide string to UTF-8 string
*/
bool wide_to_utf8(const wchar_t * wide_string, size_t string_len, std::string & utf8,  bool clear = true, int mode = 1);
bool wide_to_utf8(const wchar_t * wide_string,                    std::string & utf8,  bool clear = true, int mode = 1);
bool wide_to_utf8(const std::wstring & wide_string,               std::string & utf8,  bool clear = true, int mode = 1);

template<typename StreamType>
bool wide_to_utf8(const wchar_t * wide_string, size_t string_len, StreamType & utf8, int mode = 1);

template<typename StreamType>
bool wide_to_utf8(const wchar_t * wide_string, StreamType & utf8, int mode = 1);

template<typename StreamType>
bool wide_to_utf8(const std::wstring & wide_string, StreamType & utf8, int mode = 1);



bool wide_to_utf8(const wchar_t * wide_string, size_t string_len, char * utf8, size_t utf8_len, size_t & utf8_written, int mode = 1);
bool wide_to_utf8(const wchar_t * wide_string,                    char * utf8, size_t utf8_len, size_t & utf8_written, int mode = 1);
bool wide_to_utf8(const std::wstring & wide_string,               char * utf8, size_t utf8_len, size_t & utf8_written, int mode = 1);

bool wide_to_utf8(const wchar_t * wide_string, size_t string_len, char * utf8, size_t utf8_len, int mode = 1);
bool wide_to_utf8(const wchar_t * wide_string,                    char * utf8, size_t utf8_len, int mode = 1);
bool wide_to_utf8(const std::wstring & wide_string,               char * utf8, size_t utf8_len, int mode = 1);

template<typename StreamType>
void wide_stream_to_utf8(StreamType & buffer, std::string & utf8, bool clear = true, int mode = 1); // not tested

template<typename StreamType>
bool wide_stream_to_utf8(const Stream & stream, StreamType & utf8, bool clear = true, int mode = 1);

template<typename StreamTypeIn, typename StreamTypeOut>
void wide_stream_to_utf8(StreamTypeIn & buffer, StreamTypeOut & utf8, int mode = 1); // not tested, IMPROVE ME add clear parameter, mode parameter is not used




} // namespace


#include "utf8/utf8_templates.h"

#endif