%{
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include "symtable.h"
%}

%start Input
%token STRUCT END METHOD VAR IF THEN ELSE WHILE DO RETURN NOT OR THIS
%token IDENT NUM ASSIGN

@macro xxputsin(xx,)
	@i xx = @Statement.sin@;
@end

@macro statinout()
	@i @Statement.sout@ = @Statement.sin@;
	/* das
	 *> xxputsin(@Statement.sout@,)
	 * geht nicht, weil verschachtelte macros deaktiviert sind */
@end

@autoinh s
/* f .. fields
 * s .. symbols  */
@attributes { char *name; } IDENT
@attributes { struct symbol *f; struct symbol *s; } Program
@attributes { struct symbol *f; } Idents Structdef Parms
@attributes { struct symbol *s; } Methoddef Statseq Lexpr Expr Minusterm Multerm Orterm
Term Exprs Feld
@attributes { struct symbol *sin; struct symbol *sout; } Statement

@traversal @postorder c

%%
Input:
	  Program
	  @{
	  	@i @Program.s@ = @Program.f@;
	  @}
	;

Program:
	  Methoddef ';' Program
	  @{
	    @i @Program.0.f@ = @Program.1.f@;
	  @}
	  
	| Structdef ';' Program
	  @{
	    @i @Program.0.f@ = tab_merge(@Structdef.f@, @Program.1.f@, 1);
	  @}

	|
	  @{
		@i @Program.0.f@ = new_tab();
	  @}
	;

Methoddef:
	  METHOD IDENT '(' Parms ')' Statseq END
	  @{
	    @i @Statseq.s@ = tab_merge(@Methoddef.s@, @Parms.f@, 0);
	  @}
	;

Structdef:
	  STRUCT Idents END
	  @{
	    @i @Structdef.f@ = @Idents.f@;
	  @}
	;

Parms:
	  /* lokale Vars werden in Statement in die tabelle eingefuegt */
	  IDENT Parms
	  @{
	    @i @Parms.0.f@ = tab_add_symbol(@Parms.1.f@, @IDENT.name@, S_VAR, 1);
	  @}

	|
	  @{
	    @i @Parms.f@ = new_tab();
	  @}
	;

Idents:
	  IDENT Idents
	  @{
	    @i @Idents.0.f@ = tab_add_symbol(@Idents.1.f@, @IDENT.name@, S_FIELD, 1);
	  @}

	|
	  @{
	    @i @Idents.f@ = new_tab();
	  @}
	;

Statseq:
	  Statement ';' Statseq
	  @{
		@i @Statement.sin@ = @Statseq.0.s@;
		@i @Statseq.1.s@ = @Statement.sout@;
	  @}

	|
	;

Statement:
	  Lexpr ASSIGN Expr
	  @{
	  	statinout()
		xxputsin(@Lexpr.s@,)
		xxputsin(@Expr.s@,)
	  @}

	| VAR IDENT ASSIGN Expr
	  @{
		@i @Statement.sout@ = tab_add_symbol(clone_tab(@Statement.sin@), @IDENT.name@, S_VAR, 1);
		xxputsin(@Expr.s@,)
	  @}

	| Expr
	  @{
	  	statinout()
		xxputsin(@Expr.s@,)
	  @}

	| IF Expr THEN Statseq END
	  @{
	  	statinout()
		xxputsin(@Expr.s@,)
		xxputsin(@Statseq.s@,)
	  @}

	| IF Expr THEN Statseq ELSE Statseq END
	  @{
	  	statinout()
		xxputsin(@Expr.s@,)
		xxputsin(@Statseq.0.s@,)
		xxputsin(@Statseq.1.s@,)
	  @}

	| WHILE Expr DO Statseq END
	  @{
	  	statinout()
		xxputsin(@Expr.s@,)
		xxputsin(@Statseq.s@,)
	  @}

	| RETURN Expr
	  @{
	  	statinout()
		xxputsin(@Expr.s@,)
	  @}
	;

Lexpr:
	  IDENT
	  @{
	  	@c check_variable(@Lexpr.s@, @IDENT.name@);
	  @}

	| Feld
	;

Feld: Term '.' IDENT
	  @{
	  	@c check_field(@Feld.s@, @IDENT.name@);
	  @}
	;

Expr:
	  Term
	| NOT Term
	| Term Minusterm
	| Term Multerm
	| Term Orterm
	| Term '<' Term
	| Term '=' Term
	;

Minusterm:
	  '-' Term Minusterm
	| '-' Term
	;

Multerm:
	  '*' Term Multerm
	| '*' Term
	;

Orterm:
	  OR Term Orterm
	| OR Term
	;

Term:
	  '(' Expr ')'
	| NUM
	| '-' NUM
	| THIS
	| IDENT
	  @{
	  	@c check_variable(@Term.s@, @IDENT.name@);
	  @}

	| Feld
	| IDENT '(' Exprs ')'
	  @{
	  	@c check_variable(@Term.s@, @IDENT.name@);
	  @}

	| Term '.' IDENT '(' Exprs ')'
	  @{
	  	@c check_variable(@Term.s@, @IDENT.name@);
	  @}
	;

/* beachte dass hier auch "nichts" vorkommen kann
 * sonst waer ein aufruf der art 'f()' nicht
 * moeglich (leere parameterliste) */
Exprs:
	| Expr
	| Exprs ',' Expr
	;
%%

extern int yylex();
extern int yylineno;

int yyerror(char *error_text)
{
	fprintf(stderr,"Zeile %i: %s\n", yylineno, error_text);
	exit(2);
}

int main(int argc, char **argv)
{
	#if 0
	yydebug=1;
	#endif
	yyparse();
	return 0;
}