/* STAT1.C */

#include "stdafx.h"

#include <string.h>
//#include <alloc.h>

#include "inp.h"
#include "out.h"
#include "lex.h"
#include "code1.h"
#include "expr1.h"
#include "stat1.h"

/******************************* STATEMENTS *******************************/

Stat * statement (void)
{
  Stat * result = NULL;

  if (sy==GOTO_)                               /* goto */
  {
     info ("goto");
     NextSymbol ();
	 result = new Stat;
	 result->tag = GotoStat;
	 result->e1 = expression ();
     CheckSymbol (SEMICOLON);
  }

  else if (sy==CONTINUE_)                      /* continue */
  {
     info ("continue");
     NextSymbol ();
     CheckSymbol (SEMICOLON);
  }

  else if (sy==BREAK_)                         /* break */
  {
     info ("break");
     NextSymbol ();
     CheckSymbol (SEMICOLON);
  }

  else if (sy==RETURN_)                        /* return */
  {
     info ("return");
     NextSymbol ();
     if (sy!=SEMICOLON) expression ();
     CheckSymbol (SEMICOLON);
  }

  else if (sy==WHILE_)                         /* while */
  {
     open_info ("while");
     NextSymbol ();
     CheckSymbol (LPAR);
     expression ();
     CheckSymbol (RPAR);

     statement ();
     close_info ();
  }

  else if (sy==DO_)                            /* do */
  {
     open_info ("do");
     NextSymbol ();

     statement ();

     CheckSymbol (WHILE_);
     CheckSymbol (LPAR);
     expression ();
     CheckSymbol (RPAR);
     CheckSymbol (SEMICOLON);
     close_info ();
  }

  else if (sy==FOR_)                           /* for */
  {
     open_info ("for");
     NextSymbol ();
     CheckSymbol (LPAR);

     if (sy!=SEMICOLON) expression ();
     CheckSymbol (SEMICOLON);

     if (sy!=SEMICOLON) expression ();
     CheckSymbol (SEMICOLON);

     if (sy!=RPAR) expression ();
     CheckSymbol (RPAR);

     statement ();

	 close_info ();
  }

  else if (sy==IF_)                            /* if */
  {
     open_info ("if");
     NextSymbol ();
     CheckSymbol (LPAR);
     expression ();
     CheckSymbol (RPAR);
     close_info ();

     LAB_TYP lab_else, lab_end;
     new_label (lab_else); /* jmeno pro prostredni navesti */
     new_label (lab_end); /* jmeno pro koncove navesti */
     send_ext ("JF", lab_else); /* pokud neni podminka splnena skoc na else */

     open_info ("then");
     statement ();
     close_info ();

     if (sy==ELSE_)
     {
        NextSymbol ();
        send_ext ("JMP", lab_end); /* skok na konec prikazu */
        send_label (lab_else); /* umisti prostredni navesti */

        open_info ("else");
        statement ();
        close_info ();
     }
     else
     {
        send_label (lab_else); /* prostredni navesti na stejnem miste jako koncove */
     }

     send_label (lab_end); /* umisti koncove navesti */
  }

  else if (sy==SWITCH_)                        /* switch */
  {
     open_info ("switch");

     NextSymbol ();
     CheckSymbol (LPAR);
     expression ();
     CheckSymbol (RPAR);

     statement ();
     close_info ();
  }

  else if (sy==LBRACE)                         /* { } */
  {
     open_info ("compound statement");
     NextSymbol ();

     while (sy!=RBRACE)
        statement ();

     NextSymbol ();
     close_info ();
  }

  else if (sy==CASE_)                          /* case */
  {
     info ("case");

     NextSymbol ();
     expression ();
     CheckSymbol (COLON);
  }

  else if (sy==DEFAULT_)                       /* default */
  {
     info ("default");

     NextSymbol ();
     CheckSymbol (COLON);
  }

  else                                         /* label, expression, empty statement */
  {
     info ("simple statement");

     if (sy != SEMICOLON)
     {
        expression ();

        if (sy==COLON)
           statement ();
     }

     CheckSymbol (SEMICOLON);
  }

  return result;
}