/**********************************************************************
 Java CUP specification for a parser for C-- programs
 **********************************************************************/

import java_cup.runtime.*;
import java.util.*;

parser code {:

public void syntax_error(Symbol currToken) {
    if (currToken.value == null) {
       Errors.fatal(0,0, "Syntax error at end of file");
    }
    else {
       Errors.fatal(((TokenVal)currToken.value).linenum,
	            ((TokenVal)currToken.value).charnum,
		    "Syntax error");
    }
    System.exit(-1);
}
:};


/* Terminals (tokens returned by the scanner)
 *
 * NOTE: You will need to change the types of the values returned for
 *       ID and STRINGLITERAL tokens if you used types other than
 *       IdTokenVal and StrLitTokenVal in your scanner.
 *
 *       You will also need to add types for any other terminals whose
 *       values you use.
 */

terminal 	        INT;
terminal 	        BOOL;
terminal 	        VOID;
terminal 	        TRUE;
terminal 	        FALSE;
terminal 	        IF;
terminal 	        ELSE;
terminal 	        WHILE;
terminal 	        CIN;
terminal 	        COUT;
terminal 	        RETURN;
terminal IdTokenVal     ID;
terminal IntLitTokenVal INTLITERAL;
terminal StrLitTokenVal STRINGLITERAL;
terminal 	        LCURLY;
terminal 	        RCURLY;
terminal 	        LSQBRACKET;
terminal 	        RSQBRACKET;
terminal 	        LPAREN;
terminal 	        RPAREN;
terminal 	        COMMA;
terminal 	        ASSIGN;
terminal 	        SEMICOLON;
terminal 	        PLUS;
terminal 	        MINUS;
terminal 	        TIMES;
terminal 	        DIVIDE;
terminal 	        NOT;
terminal 	        AND;
terminal 	        OR;
terminal 	        EQUALS;
terminal 	        NOTEQUALS;
terminal 	        LESS;
terminal 	        GREATER;
terminal 	        LESSEQ;
terminal 	        GREATEREQ;
terminal 	        READ;
terminal 	        WRITE;

/* Nonterminals
 *
 * NOTE: You will need to add more nonterminals to this list as you
 *       add productions to the grammar below.
 */
non terminal ProgramNode      program;
non terminal LinkedList       declList;
non terminal DeclNode	      decl;
non terminal VarDeclNode      varDecl;
non terminal TypeNode	      type;
non terminal IdNode	      id;
 
/* NOTE: Add precedence and associativity declarations here */

start with program;

/*
 * grammar with actions
 *
 * NOTE: add more grammar rules below
 */
program		::= declList: d
		{: RESULT = new ProgramNode(new DeclListNode(d));
		:}
		;

declList 	::= declList:dl decl:d
		{: dl.addLast(d);
		   RESULT = dl;
		:}
		| /* epsilon */
		{: RESULT = new LinkedList();
		:}
		;

decl		::= varDecl:v
		{: RESULT = v;
		:}
		;

varDecl		::= type: t id: i SEMICOLON
		{: RESULT = new VarDeclNode(t, i, VarDeclNode.NOT_ARRAY);
		:}
		;

type		::= INT
		{: RESULT = new IntNode();
		:}
		;

id              ::= ID:i
		{: RESULT = new IdNode(i.linenum, i.charnum, i.idVal);
		:}
		;