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

/* 
 * Copyright (c) 2008-2012, 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.
 */

#include <cstdlib>
#include <wchar.h>
#include "spaceparser.h"
#include "utf8/utf8.h"


namespace PT
{



SpaceParser::SpaceParser()
{
	root_space = 0;
	SetDefault();
}


void SpaceParser::SetSpace(Space * pspace)
{
	root_space = pspace;
}


void SpaceParser::SetSpace(Space & pspace)
{
	root_space = &pspace;
}


void SpaceParser::SetDefault()
{
	// you can change this separators to what you want
	// you shoud not use only white characters here (as expected by IsWhite() method)
	// and new line characters ('\n')
	separator       = '=';
	commentary      = '#';
	list_start      = '(';
	list_end        = ')';
	list_delimiter  = ',';
	split_single    = true;
	skip_empty      = false;
	use_escape_char = true;
	input_as_utf8   = true;
}


void SpaceParser::SplitSingle(bool split)
{
	split_single = split;
}


void SpaceParser::SkipEmpty(bool skip)
{
	skip_empty = skip;
}


void SpaceParser::UseEscapeChar(bool escape)
{
	use_escape_char = escape;
}


void SpaceParser::UTF8(bool utf)
{
	input_as_utf8 = utf;
}




SpaceParser::Status SpaceParser::Parse(const char * file_name)
{
	reading_from_file = true;

	file.clear();
	file.open(file_name, std::ios_base::binary | std::ios_base::in);
	
	if( file )
	{
		Parse();
		file.close();
	}
	else
	{
		status = cant_open_file;
	}
	
return status;
}



SpaceParser::Status SpaceParser::Parse(const std::string & file_name)
{
	return Parse(file_name.c_str());
}




SpaceParser::Status SpaceParser::Parse(const wchar_t * file_name)
{
	PT::WideToUTF8(file_name, afile_name);
	return Parse(afile_name.c_str());
}



SpaceParser::Status SpaceParser::Parse(const std::wstring & file_name)
{
	return Parse(file_name.c_str());
}



SpaceParser::Status SpaceParser::ParseString(const char * str)
{
	reading_from_file         = false;
	reading_from_wchar_string = false;
	pchar_ascii               = str;
	pchar_unicode             = 0;

	Parse();

return status;
}


SpaceParser::Status SpaceParser::ParseString(const std::string & str)
{
	return ParseString(str.c_str());
}


SpaceParser::Status SpaceParser::ParseString(const wchar_t * str)
{
	reading_from_file         = false;
	reading_from_wchar_string = true;
	pchar_unicode             = str;
	pchar_ascii               = 0;

	Parse();

return status;
}


SpaceParser::Status SpaceParser::ParseString(const std::wstring & str)
{
	return ParseString(str.c_str());
}


void SpaceParser::Parse()
{
	if( !root_space )
	{
		status = no_space;
		return;
	}

	line   = 1;
	status = ok;
	space  = root_space;
	ReadChar();
	SkipWhiteLines();

	ParseLoop();

	if( status == ok && space != root_space )
	{
		// last closing ')' characters are missing (closing a space)
		status = syntax_error;
	}

	token.clear();
	key.clear();
	value.clear();
}


void SpaceParser::ParseLoop()
{
	while( status == ok && lastc != -1 )
	{
		if( lastc == list_end )
		{
			SpaceEnds();
		}
		else
		{
			ReadKey();
			SkipWhite();

			if( lastc == list_start )
			{
				SpaceStarts();
			}
			else
			if( lastc == separator )
			{
				ReadValue();
				AddKeyValuePair();
			}
			else
			{
				status = syntax_error;
			}
		}

		if( status == ok )
			SkipWhiteLines();
	}
}


void SpaceParser::SpaceEnds()
{
	if( space == root_space )
	{
		// there cannot be a loose list end character in the global space
		status = syntax_error;
	}
	else
	{
		space = space->parent;
		ReadChar(); // skipping closing space character ')'
		SkipWhite();
	}
}


void SpaceParser::SpaceStarts()
{
	Space * new_space = new Space();
	space->spaces.push_back(new_space);
	new_space->parent = space;
	new_space->name   = key;
	space = new_space;

	ReadChar();	// skipping space starts character ')'
}





/*
	those white characters here should be the same as in space.h
*/
bool SpaceParser::IsWhite(int c)
{
	// dont use '\n' here
	// 13 (\r) is at the end of a line in a dos file \r\n
	// 160 is an unbreakable space
	if( c==' ' || c=='\t' || c==13 || c==160 )
		return true;
		
return false;	
}



void SpaceParser::SkipWhite()
{
	while( IsWhite(lastc) || lastc == commentary )
	{
		if( lastc == commentary )
			SkipLine();
		else
			ReadChar();
	}
}


void SpaceParser::SkipWhiteLines()
{
	while( IsWhite(lastc) || lastc == commentary || lastc=='\n' )
	{
		if( lastc == commentary )
			SkipLine();
		else
			ReadChar();
	}
}


void SpaceParser::SkipLine()
{
	while( lastc != -1 && lastc != '\n' )
		ReadChar();	
}



void SpaceParser::Trim(std::wstring & s)
{
std::wstring::size_type i;
	
	if( s.empty() )
		return;
	
	// looking for white characters at the end
	for(i=s.size()-1 ; i>0 && IsWhite(s[i]) ; --i);
	
	if( i==0 && IsWhite(s[i]) )
	{
		// the whole string has white characters
		s.clear();
		return;
	}
	
	// deleting white characters at the end
	if( i != s.size() - 1 )
		s.erase(i+1, std::wstring::npos);
	
	// looking for white characters at the beginning
	for(i=0 ; i<s.size() && IsWhite(s[i]) ; ++i);
	
	// deleting white characters at the beginning
	if( i != 0 )
		s.erase(0, i);
}







void SpaceParser::DeleteFromTable(const std::wstring & var)
{
	Space::Table::iterator i = space->table.find(var);

	if( i != space->table.end() )
		space->table.erase(i);
}



void SpaceParser::DeleteFromTableSingle(const std::wstring & var)
{
	Space::TableSingle::iterator i = space->table_single.find(var);

	if( i != space->table_single.end() )
		space->table_single.erase(i);
}




void SpaceParser::ReadTokenQuoted()
{
	ReadChar(); // skipping the first quotation mark

	while( lastc != -1 && (char_was_escaped || lastc != '"') )
	{
		token += static_cast<wchar_t>(lastc);
		ReadChar();
	}

	if( !char_was_escaped && lastc == '"' )
		ReadChar(); // skipping the last quotation mark
	else
		status = syntax_error;
}


void SpaceParser::ReadTokenSingle(bool white_delimit, bool new_line_delimit, int delimit1, int delimit2)
{
	while( true )
	{
		if( lastc == commentary )
			SkipLine();

		if( lastc == -1									||
			(!char_was_escaped							&&
			(
				lastc == list_end						||
				(white_delimit    && IsWhite(lastc))	||
				(new_line_delimit && lastc == '\n')		||
				(delimit1 != -1   && lastc == delimit1)	||
				(delimit2 != -1   && lastc == delimit2)
			) ) )

		{
			break;
		}

		token += static_cast<wchar_t>(lastc);
		ReadChar();
	}

	Trim(token);
}


void SpaceParser::ReadToken(bool white_delimit, bool new_line_delimit, int delimit1, int delimit2)
{
	token.clear();
	SkipWhite();
	
	if( !char_was_escaped && lastc == '"' )
		ReadTokenQuoted();
	else
		ReadTokenSingle(white_delimit, new_line_delimit, delimit1, delimit2);
}


void SpaceParser::ReadKey()
{
	ReadToken(false, true, separator, list_start);
	key = token;
	SkipWhite();
}



void SpaceParser::ReadValueList()
{
	ReadChar(); // skipping the first list character ')'
	SkipWhiteLines();

	while( lastc != -1 && lastc != list_end )
	{
		ReadToken(true, true, list_delimiter, list_end);
		value.push_back(token);

		SkipWhiteLines();

		if( lastc == list_delimiter )
		{
			ReadChar();
			SkipWhiteLines();
		}
	}

	if( lastc == list_end )
	{
		ReadChar(); // skipping the last list character ')'
		SkipWhite();
	}
	else
	{
		status = syntax_error; // missing one ')'
	}
}


void SpaceParser::ReadValueSingle()
{
	SkipWhite();
	ReadToken(false, true, -1, -1);
	value.push_back(token);
	SkipWhite();
}


void SpaceParser::ReadValue()
{
	ReadChar(); // skipping separator '='
	value.clear();
	SkipWhite();

	if( lastc == list_start )
		ReadValueList();
	else
		ReadValueSingle();

	SkipWhiteLines();
}


void SpaceParser::AddKeyValuePair()
{
	if( value.empty() && skip_empty )
	{
		DeleteFromTable(key);
		DeleteFromTableSingle(key);
		return;
	}

	if( split_single && value.size() == 1 )
	{
		space->table_single[key] = value[0];
		DeleteFromTable(key);
	}
	else
	{
		space->table[key] = value;
		DeleteFromTableSingle(key);
	}
}






int SpaceParser::ReadUTF8Char()
{
int c;
bool correct;

	lastc = -1;

	do
	{
		PT::UTF8ToInt(file, c, correct);

		if( !file )
			return lastc;
	}
	while( !correct );

	lastc = c;

	if( lastc == '\n' )
		++line;
	
return lastc;
}



int SpaceParser::ReadASCIIChar()
{
	lastc = file.get();

	if( lastc == '\n' )
		++line;
	
return lastc;
}




int SpaceParser::ReadCharFromWcharString()
{
	if( *pchar_unicode == 0 )
		lastc = -1;
	else
		lastc = *(pchar_unicode++);

	if( lastc == '\n' )
		++line;

return lastc;
}


int SpaceParser::ReadCharFromUTF8String()
{
int c;
bool correct;

	lastc = -1;

	do
	{
		size_t len = PT::UTF8ToInt(pchar_ascii, c, correct);
		pchar_ascii += len;

		if( *pchar_ascii == 0 )
			return lastc;
	}
	while( !correct );

	lastc = c;

	if( lastc == '\n' )
		++line;
	
return lastc;
	
}


int SpaceParser::ReadCharFromAsciiString()
{
	if( *pchar_ascii == 0 )
		lastc = -1;
	else
		lastc = *(pchar_ascii++);

	if( lastc == '\n' )
		++line;

return lastc;
}


int SpaceParser::ReadCharNoEscape()
{
	if( reading_from_file )
	{
		if( input_as_utf8 )
			return ReadUTF8Char();
		else
			return ReadASCIIChar();
	}
	else
	{
		if( reading_from_wchar_string )
		{
			return ReadCharFromWcharString();
		}
		else
		{
			if( input_as_utf8 )
				return ReadCharFromUTF8String();
			else
				return ReadCharFromAsciiString();
		}
	}
}


int SpaceParser::ReadChar()
{
	char_was_escaped = false;
	ReadCharNoEscape();

	if( use_escape_char && lastc == '\\' )
	{
		char_was_escaped = true;
		ReadCharNoEscape();

		switch(lastc)
		{
		case '0':	lastc = 0;		break;
		case 't':	lastc = '\t';	break;
		case 'r':	lastc = '\r';	break;
		case 'n':	lastc = '\n';	break;
		// in other cases we return the last character
		}
	}

return lastc;
}



} // namespace