/***************************************************************************
                   xterm256generator.cpp  -  description
                             -------------------
    begin                : Oct 13 2006
    copyright            : (C) 2006 by Andre Simon
    email                : andre.simon1@gmx.de
 ***************************************************************************/


/*
This file is part of Highlight.

Highlight 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.

Highlight 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 Highlight.  If not, see <http://www.gnu.org/licenses/>.
*/


#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <sstream>

#include "xterm256generator.h"
#include "charcodes.h"
#include "version.h"

using namespace std;

namespace highlight
{
	Xterm256Generator::Xterm256Generator() : CodeGenerator ( XTERM256 )
	{

		newLineTag = "\n";
		spacer = " ";
	}

	Xterm256Generator::~Xterm256Generator() {}

	string Xterm256Generator::getHeader()
	{
		return string();
	}

	void Xterm256Generator::printBody()
	{
		processRootState();
	}

	string Xterm256Generator::getFooter()
	{
		return string();
	}

	string Xterm256Generator::maskCharacter ( unsigned char c )
	{
		return string ( 1, c );
	}

	void Xterm256Generator::initOutputTags ( )
	{
		openTags.push_back ( getOpenTag ( docStyle.getDefaultStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getStringStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getNumberStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getSingleLineCommentStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getCommentStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getEscapeCharStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getDirectiveStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getDirectiveStringStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getLineStyle() ) );
		openTags.push_back ( getOpenTag ( docStyle.getSymbolStyle() ) );

		for ( int i=0;i<NUMBER_BUILTIN_STATES; i++ )
		{
			closeTags.push_back ( "\033[m" );
		}
	}

	string  Xterm256Generator::getOpenTag ( const ElementStyle &col )
	{

		Colour c= col.getColour();
		unsigned char  rgb[3];
		rgb[0] = ( unsigned char ) strtoll ( c.getRed ( HTML ).c_str(), NULL, 16 );
		rgb[1] = ( unsigned char ) strtoll ( c.getGreen ( HTML ).c_str(), NULL, 16 );
		rgb[2] = ( unsigned char ) strtoll ( c.getBlue ( HTML ).c_str(), NULL, 16 );

		ostringstream s;
		s  << "\033[38;5;"<< ( int ) rgb2xterm ( rgb ) << "m";
		return  s.str();
	}

	string Xterm256Generator::getKeywordOpenTag ( unsigned int styleID )
	{
		return getOpenTag ( docStyle.getKeywordStyle ( langInfo.getKeywordClasses() [styleID] ) );
	}

	string Xterm256Generator::getKeywordCloseTag ( unsigned int styleID )
	{
		return "\033[m";
	}

	/* the following functions are based on Wolfgang Frischs xterm256 converter utility:
	   http://frexx.de/xterm-256-notes/
	*/

	void Xterm256Generator::xterm2rgb ( unsigned char color, unsigned char* rgb )
	{
		// 16 basic colors
		if ( color<16 )
		{
			rgb[0] = basic16[color][0];
			rgb[1] = basic16[color][1];
			rgb[2] = basic16[color][2];
		}

		// color cube color
		if ( color>=16 && color<=232 )
		{
			color-=16;
			rgb[0] = valuerange[ ( color/36 ) %6];
			rgb[1] = valuerange[ ( color/6 ) %6];
			rgb[2] = valuerange[color%6];
		}

		// gray tone
		if ( color>=233 && color<=253 )
		{
			rgb[0]=rgb[1]=rgb[2] = 8+ ( color-232 ) *0x0a;
		}
	}

	void Xterm256Generator::maketable()
	{
		unsigned char c, rgb[3];
		for ( c=0;c<=253;c++ )
		{
			xterm2rgb ( c,rgb );
			colortable[c][0] = rgb[0];
			colortable[c][1] = rgb[1];
			colortable[c][2] = rgb[2];
		}
	}

	unsigned char Xterm256Generator::rgb2xterm ( unsigned char* rgb )
	{
		unsigned char c, best_match=0;
		double d, smallest_distance;

		if ( !initialized )
		{
			maketable();
			initialized = true;
		}

		smallest_distance = 10000000000.0;

		for ( c=0;c<=253;c++ )
		{
			d = pow ( colortable[c][0]-rgb[0],2.0 ) +
			    pow ( colortable[c][1]-rgb[1],2.0 ) +
			    pow ( colortable[c][2]-rgb[2],2.0 );
			if ( d<smallest_distance )
			{
				smallest_distance = d;
				best_match=c;
			}
		}
		return best_match;
	}

	bool Xterm256Generator::initialized=false;
	unsigned char Xterm256Generator::colortable[254][3];

	const unsigned char Xterm256Generator::valuerange[] = { 0x00, 0x5F, 0x87, 0xAF, 0xD7, 0xFF };

	const unsigned char Xterm256Generator::basic16[16][3] =
	{
		{ 0x00, 0x00, 0x00 }, // 0
		{ 0xCD, 0x00, 0x00 }, // 1
		{ 0x00, 0xCD, 0x00 }, // 2
		{ 0xCD, 0xCD, 0x00 }, // 3
		{ 0x00, 0x00, 0xEE }, // 4
		{ 0xCD, 0x00, 0xCD }, // 5
		{ 0x00, 0xCD, 0xCD }, // 6
		{ 0xE5, 0xE5, 0xE5 }, // 7
		{ 0x7F, 0x7F, 0x7F }, // 8
		{ 0xFF, 0x00, 0x00 }, // 9
		{ 0x00, 0xFF, 0x00 }, // 10
		{ 0xFF, 0xFF, 0x00 }, // 11
		{ 0x5C, 0x5C, 0xFF }, // 12
		{ 0xFF, 0x00, 0xFF }, // 13
		{ 0x00, 0xFF, 0xFF }, // 14
		{ 0xFF, 0xFF, 0xFF }  // 15
	};


}