Application: gvSIG desktop

package com.iver.utiles.console.jedit;

/*

 * TeXTokenMarker.java - TeX/LaTeX/AMS-TeX token marker

 * Copyright (C) 1998 Slava Pestov

 *

 * You may use and modify this package for any purpose. Redistribution is

 * permitted, in both source and binary form, provided that this notice

 * remains intact in all source distributions of this package.

 */

import javax.swing.text.Segment;

/**

 * TeX token marker.

 *

 * @author Slava Pestov

 * @version $Id$

 */

public class TeXTokenMarker extends TokenMarker

{

        // public members

        public static final byte BDFORMULA = Token.INTERNAL_FIRST;

        public static final byte EDFORMULA = (byte)(Token.INTERNAL_FIRST + 1);

        public byte markTokensImpl(byte token, Segment line, int lineIndex)

        {

                char[] array = line.array;

                int offset = line.offset;

                int lastOffset = offset;

                int length = line.count + offset;

                boolean backslash = false;

loop:                for(int i = offset; i < length; i++)

                {

                        int i1 = (i+1);

                        char c = array[i];

                        // if a backslash is followed immediately

                        // by a non-alpha character, the command at

                        // the non-alpha char. If we have a backslash,

                        // some text, and then a non-alpha char,

                        // the command ends before the non-alpha char.

                        if(Character.isLetter(c))

                        {

                                backslash = false;

                        }

                        else

                        {

                                if(backslash)

                                {

                                        // \<non alpha>

                                        // we skip over this character,

                                        // hence the `continue'

                                        backslash = false;

                                        if(token == Token.KEYWORD2 || token == EDFORMULA)

                                                token = Token.KEYWORD2;

                                        addToken(i1 - lastOffset,token);

                                        lastOffset = i1;

                                        if(token == Token.KEYWORD1)

                                                token = Token.NULL;

                                        continue;

                                }

                                else

                                {

                                        //\blah<non alpha>

                                        // we leave the character in

                                        // the stream, and it's not

                                        // part of the command token

                                        if(token == BDFORMULA || token == EDFORMULA)

                                                token = Token.KEYWORD2;

                                        addToken(i - lastOffset,token);

                                        if(token == Token.KEYWORD1)

                                                token = Token.NULL;

                                        lastOffset = i;

                                }

                        }

                        switch(c)

                        {

                        case '%':

                                if(backslash)

                                {

                                        backslash = false;

                                        break;

                                }

                                addToken(i - lastOffset,token);

                                addToken(length - i,Token.COMMENT1);

                                lastOffset = length;

                                break loop;

                        case '\\':

                                backslash = true;

                                if(token == Token.NULL)

                                {

                                        token = Token.KEYWORD1;

                                        addToken(i - lastOffset,Token.NULL);

                                        lastOffset = i;

                                }

                                break;

                        case '$':

                                backslash = false;

                                if(token == Token.NULL) // singe $

                                {

                                        token = Token.KEYWORD2;

                                        addToken(i - lastOffset,Token.NULL);

                                        lastOffset = i;

                                }

                                else if(token == Token.KEYWORD1) // \...$

                                {

                                        token = Token.KEYWORD2;

                                        addToken(i - lastOffset,Token.KEYWORD1);

                                        lastOffset = i;

                                }

                                else if(token == Token.KEYWORD2) // $$aaa

                                {

                                        if(i - lastOffset == 1 && array[i-1] == '$')

                                        {

                                                token = BDFORMULA;

                                                break;

                                        }

                                        token = Token.NULL;

                                        addToken(i1 - lastOffset,Token.KEYWORD2);

                                        lastOffset = i1;

                                }

                                else if(token == BDFORMULA) // $$aaa$

                                {

                                        token = EDFORMULA;

                                }

                                else if(token == EDFORMULA) // $$aaa$$

                                {

                                        token = Token.NULL;

                                        addToken(i1 - lastOffset,Token.KEYWORD2);

                                        lastOffset = i1;

                                }

                                break;

                        }

                }

                if(lastOffset != length)

                        addToken(length - lastOffset,token == BDFORMULA

                                || token == EDFORMULA ? Token.KEYWORD2 :

                                token);

                return (token != Token.KEYWORD1 ? token : Token.NULL);

        }

}