/* **********************************************
 * Duale Hochschule Baden-Württemberg Karlsruhe
 * Prof. Dr. Jörn Eisenbiegler
 * 
 * Vorlesung Übersetzerbau
 * Praxis AS-Scanner mit JFlex 4 
 * 
 * **********************************************
 */

package de.dhbw.compiler.jflexasscanner;

%% 

%class JFlexASScanner
%function nextToken
%type  Token 

%unicode
%line
%column
%public
%final

%xstate FRAC, EXP, STR, NULL, ID, NUM

%{
    String idValue = "";
    int intValue = 0;
%}

WhiteSpace     = [ \t\b\r\n]+
SmallChars     = [a-z]
CapitalChars   = [A-Z]
Numbers        = [0-9]
AllChars       = [a-zA-Z0-9]

%eofval{
    return new Token(Token.EOF, "", yyline+1, yycolumn+1);
%eofval}

%%
//[^]			{ return new Token(Token.INVALID, yytext(), yyline+1, yycolumn+1); }
{WhiteSpace}             { /* Ignore */ }
<YYINITIAL> {
    "null"                       { return new Token(Token.NULL, yytext(), yyline+1, yycolumn+1); }
    {AllChars}                   { yybegin(ID);
                                   idValue = yytext(); System.out.println("BEGIN ID <"+idValue+">"); }
    {Numbers}                    { yybegin(NUM);
                                   intValue = yycharat(0)-'0'; }
    [\[]                         { return new Token(Token.LSBR, yytext(), yyline+1, yycolumn+1); }
    [\]]                         { return new Token(Token.RSBR, yytext(), yyline+1, yycolumn+1); }
    [,]                          { return new Token(Token.COMMA, yytext(), yyline+1, yycolumn+1); }
}

<NUM> {
    {Numbers}                      { intValue = intValue * 10 + yycharat(0) - '0'; }
    {SmallChars} | {CapitalChars}  { yybegin(ID); idValue = String.valueOf(intValue); yypushback(1); }
    [^]                            { yybegin(YYINITIAL);
                                     yypushback(1);
                                     return new NumToken(String.valueOf(intValue), yyline+1, yycolumn+1); }

<ID> {
    {AllChars}                      { idValue += yytext(); }
}
<ID>        [^]                      { yybegin(YYINITIAL);System.out.println("PUSHBACK BEFORE <"+yytext()+">");
                                       yypushback(1); System.out.println("PUSHBACK AFTER <"+yytext()+">"); System.out.println("LINE <"+yyline+"> / COLUMN <"+yycolumn+">");
                                       return new Token(Token.ID, idValue, yyline+1, yycolumn); }


[^]                      { return new Token(Token.INVALID, yytext(), yyline+1, yycolumn+1);
                            /*throw new Error("Illegal character <" + yytext() + ">"); */}