import java_cup.runtime.*;
import java.io.FileInputStream;

parser code {: private Lexer L; :};

init with {: L = new Lexer(new FileInputStream(Main.filename)); :};

scan with
  {:
  Token T = L.next();
  return new java_cup.runtime.Symbol(T.type, T.first, T.last, T.spelling);
  :};

terminal CLASS, ELSE, IF, INT, BOOLEAN, RETURN, STATIC, WHILE;
terminal String NUM, BOOL, ID;
terminal GETS, PLUS, MINUS, TIMES, DIV, MOD;
terminal SEMICOLON, COMMA, LPAREN, RPAREN, LBRACE, RBRACE;
terminal EQUALS, NOTEQUAL, OR, AND;
terminal UNINIT;

non terminal ClassDecl, MethodDecls, MethodDecl, Type, FormalParams;
non terminal Block, Statements, Statement;

start with ClassDecl;

/******************** High-level structures *********************/

ClassDecl ::= CLASS ID:name LBRACE MethodDecls:mds RBRACE 
                {:RESULT = new ClassDecl(new Id(name), (MethodDecls)mds); :};

MethodDecls ::= MethodDecls:mds MethodDecl:md
                  {: ((MethodDecls)mds).append((MethodDecl)md); RESULT = mds; :}
             |  /* empty */
                  {: RESULT = new MethodDecls(); :};

MethodDecl ::= STATIC Type:type ID:name LPAREN FormalParams:fps RPAREN Block:block
                 {: RESULT = new MethodDecl((Id)type, new Id(name), (FormalParams)fps, (Block)block); :};

FormalParams ::= /* empty */ 
                   {: RESULT = new FormalParams(); :};

Type ::= INT:i 
           {: RESULT = new Id("int"); :};
      

/******************** Statements *********************/

Block ::= LBRACE Statements:ss RBRACE 
            {: RESULT = new Block((Statements)ss); :};

Statements ::= Statements:ss Statement:s
                 {: ((Statements)ss).append((Statement)s); RESULT = ss; :}
            |  /* empty */
                 {: RESULT = new Statements(); :};

Statement ::= SEMICOLON 
                {: RESULT = null; :}; 
/* Making Statement empty leads to shift-reduce conflict. See Levine,Mason,Brown, p. 232.*/


/******************** Expressions *********************/