/*********************                                                        */
/*! \file bounded_token_buffer.h
 ** \verbatim
 ** Top contributors (to current version):
 **   Christopher L. Conway, Morgan Deters
 ** This file is part of the CVC4 project.
 ** Copyright (c) 2009-2019 by the authors listed in the file AUTHORS
 ** in the top-level source directory) and their institutional affiliations.
 ** All rights reserved.  See the file COPYING in the top-level source
 ** directory for licensing information.\endverbatim
 **
 ** \brief An ANTLR3 bounded token stream.
 **
 ** An ANTLR3 bounded token stream. The stream has a bounded
 ** lookahead/behind k. Calling LT(i) with i > k or i < -k will raise
 ** an exception. Only use this factory if you *know* that the grammar
 ** has bounded lookahead (e.g., if you've set the k parameter in the 
 ** parser.
 **
 ** NOTE: ANTLR3 puts "hidden" tokens into this buffer too, so
 ** pathological inputs can exceed the k token lookahead, even if
 ** your grammar really is LL(k). Be sure that irrelevant tokens
 ** are SKIP()'d and not "hidden".
 **/

#include "cvc4parser_private.h"

#ifndef	CVC4__PARSER__BOUNDED_TOKEN_BUFFER_H
#define	CVC4__PARSER__BOUNDED_TOKEN_BUFFER_H

#include <antlr3defs.h>

namespace CVC4 {
namespace parser {

#ifdef __cplusplus
extern "C" {
#endif


/** A "super" structure for COMMON_TOKEN_STREAM. */
typedef struct BOUNDED_TOKEN_BUFFER_struct
{
    pANTLR3_COMMON_TOKEN_STREAM    commonTstream;
    pANTLR3_COMMON_TOKEN* tokenBuffer;
    // tokenNeg1, token1, token2;
    ANTLR3_UINT32 currentIndex, maxIndex, k, bufferSize;
    ANTLR3_BOOLEAN empty, done;
} BOUNDED_TOKEN_BUFFER, *pBOUNDED_TOKEN_BUFFER;

pBOUNDED_TOKEN_BUFFER
BoundedTokenBufferSourceNew(ANTLR3_UINT32 k, pANTLR3_TOKEN_SOURCE source);

void
BoundedTokenBufferFree(pBOUNDED_TOKEN_BUFFER buffer);

#ifdef __cplusplus
}/* extern "C" */
#endif

}/* CVC4::parser namespace */
}/* CVC4 namespace */

#endif /* CVC4__PARSER__BOUNDED_TOKEN_BUFFER_H */