//
// Copyright (C) 2016 Google, Inc.
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//    Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//
//    Redistributions in binary form must reproduce the above
//    copyright notice, this list of conditions and the following
//    disclaimer in the documentation and/or other materials provided
//    with the distribution.
//
//    Neither the name of Google, Inc., nor the names of its
//    contributors may be used to endorse or promote products derived
//    from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//

//
// This holds context specific to the HLSL scanner, which
// sits between the preprocessor scanner and HLSL parser.
//

#ifndef HLSLSCANCONTEXT_H_
#define HLSLSCANCONTEXT_H_

#include "../MachineIndependent/ParseHelper.h"
#include "hlslTokens.h"

namespace glslang {

class TPpContext;
class TPpToken;


//
// Everything needed to fully describe a token.
//
struct HlslToken {
    HlslToken() : string(nullptr) { loc.init(); }
    TSourceLoc loc;                // location of token in the source
    EHlslTokenClass tokenClass;    // what kind of token it is
    union {                        // what data the token holds
        glslang::TString *string;  // for identifiers
        int i;                     // for literals
        unsigned int u;
        bool b;
        double d;
    };
    // If the token is a string parsed from the source, then returns a C-style
    // string for it.  Otherwise returns a pointer to an empty string.
    const char* getCStrOrEmpty() {
      if (tokenClass == EHTokIdentifier || tokenClass == EHTokStringConstant) {
        return string->c_str();
      }
      return "";
    }
};

//
// The state of scanning and translating raw tokens to slightly richer
// semantics, like knowing if an identifier is an existing symbol, or
// user-defined type.
//
class HlslScanContext {
public:
    HlslScanContext(TParseContextBase& parseContext, TPpContext& ppContext)
        : parseContext(parseContext), ppContext(ppContext) { }
    virtual ~HlslScanContext() { }

    static void fillInKeywordMap();
    static void deleteKeywordMap();

    void tokenize(HlslToken&);
    glslang::TBuiltInVariable mapSemantic(const char*);

protected:
    HlslScanContext(HlslScanContext&);
    HlslScanContext& operator=(HlslScanContext&);

    EHlslTokenClass tokenizeClass(HlslToken&);
    EHlslTokenClass tokenizeIdentifier();
    EHlslTokenClass identifierOrType();
    EHlslTokenClass reservedWord();
    EHlslTokenClass identifierOrReserved(bool reserved);
    EHlslTokenClass nonreservedKeyword(int version);

    TParseContextBase& parseContext;
    TPpContext& ppContext;
    TSourceLoc loc;
    TPpToken* ppToken;
    HlslToken* parserToken;

    const char* tokenText;
    EHlslTokenClass keyword;
};

} // end namespace glslang

#endif // HLSLSCANCONTEXT_H_
