/*
 * [JavaCharCategory.java]
 *
 * Summary: top level enum to define the categories of character for the BatTokenizer.
 *
 * Copyright: (c) 2004-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  3.1 2009-04-12 shorter style names, improved highlighting.
 */
package com.mindprod.jprep;

/**
 * top level enum to define the categories of character for the BatTokenizer.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 3.1 2009-04-12 shorter style names, improved highlighting.
 * @since 2004-05-15
 */
@SuppressWarnings( { "EnumeratedConstantNamingConvention" } )
public enum JavaCharCategory
    {
        /**
         * @
         */
        AT,
        /**
         * backslash, used in quoting in side quotes or ticks
         */
        BACKSLASH,
        /**
         * digit 0-9
         */
        DIGIT,
        /**
         * decimal point, qualifying dot
         */
        DOT,
        /**
         * End of line character
         */
        EOL,
        /**
         * bracketting character e.g. ()[]{}
         */
        FENCE,
        /**
         * ignore control chars
         */
        IGNORE,
        /**
         * high ascii ` and chars not used in Java
         */
        OTHER,
        /**
         * chars used in identifiers, except digits, $
         */
        PLAIN,
        /**
         * _
         */
        UNDERSCORE,
        /**
         * punctuation includes ;
         */
        PUNCTUATION,
        /**
         * "
         */
        QUOTE,
        /**
         * /
         */
        SLASH,
        /**
         * space
         */
        SPACE,
        /**
         * star
         */
        STAR,
        /**
         * '
         */
        TICK;

    /**
     * Categorise one character
     *
     * @param theChar character to categorise
     *
     * @return category code, e.g. PLAIN QUOTE
     */
    static JavaCharCategory categorise( char theChar )
        {
        if ( 'a' <= theChar && theChar <= 'z' )
            {
            return PLAIN;
            }
        if ( 'A' <= theChar && theChar <= 'Z' )
            {
            return PLAIN;
            }
        if ( '0' <= theChar && theChar <= '9' )
            {
            return DIGIT;
            }
        switch ( theChar )
            {
            case ' ':
            case '\t':
            case 0xa0:// &nbsp;
                return SPACE;
            case '\n':
                return EOL;
            case '\r':
            case 127:
            case 0xfeff: /* bom */
            case 0xfffd: /* replaced bom */
                return IGNORE;
            case '$':
            case '_':
                return PLAIN;
            case '*':
                return STAR;
            case '/':
                return SLASH;
            case '\"':
                return QUOTE;
            case '\'':
                return TICK;
            case '(':
            case ')':
            case '[':
            case ']':
            case '{':
            case '}':
                return FENCE;
            case '@':// ok in comments
                return AT;
            case '.':
                return DOT;
            case '!':
            case '#':// ok in comments
            case '%':
            case '&':
            case '+':
            case ',':
            case '-':
            case ':':
            case ';':// treated as punctuation
            case '<':
            case '=':
            case '>':
            case '?':
            case '^':
            case '`':// ok in comments
            case '|':
            case '~':
                return PUNCTUATION;
            case '\\':
                return BACKSLASH;
            default:
                if ( 0 <= theChar && theChar <= 31 )
                    {
                    return IGNORE;
                    }
                else if ( 128 <= theChar )
                    {
                    // treat high bit on as ordinary alpha
                    return PLAIN;
                    }
                else
                    {
                    return OTHER;
                    }
            } // end switch
        } // end categorise
    } // end JavaCharCategory