/* vim: set ts=4 sw=4 tw=99 et:

 *

 * Copyright (C) 2012 David Anderson

 *

 * This file is part of SourcePawn.

 *

 * SourcePawn is free software: you can redistribute it and/or modify it under

 * the terms of the GNU General Public License as published by the Free

 * Software Foundation, either version 3 of the License, or (at your option)

 * any later version.

 * 

 * SourcePawn is distributed in the hope that it will be useful, but WITHOUT ANY

 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License along with

 * SourcePawn. If not, see http://www.gnu.org/licenses/.

 */

#ifndef _include_jitcraft_scanner_h_

#define _include_jitcraft_scanner_h_

#include <string>

#include "Token.h"

#include "CompileContext.h"

#include "Vector.h"

namespace ke {

class Scanner

{

    template <bool Enabled>

    friend class AutoAllowTags;

    CompileContext &cc_;

    const char *stream_;

    size_t length_;

    bool pushed_;

    bool allowTags_;

    char saved_;

    const char *pos_;

    Vector<char> literal_;

    TokenKind lastToken_;

    SourcePosition last_;

    SourcePosition cur_;

    SourcePosition begin_;

  private:

    char getChar();

    void putChar(char c);

    void eatSingleLine();

    bool eatComment();

    void calcNewLine(char c);

    int readEscapeCode();

    TokenKind stringLiteral();

    TokenKind hexLiteral();

    TokenKind numberLiteral(char first);

    TokenKind identifier(char first);

    TokenKind next();

  public:

    Scanner(CompileContext &cc, const char *stream, size_t length);

    static double ParseDouble(const char *string);

    TokenKind scan();

    TokenKind peek();

    TokenKind last() const {

        return lastToken_;

    }

    bool tagsEnabled() const {

        return allowTags_;

    }

    void setTagsEnabled(bool enabled) {

        allowTags_ = enabled;

    }

    // Beginning source position of the last instruction.

    SourcePosition begin() const {

        return begin_;

    }

    // Note: the literal may have embedded NUL characters.

    const char *literal() const {

        return literal_.buffer();

    }

    size_t literal_length() const {

        return literal_.length() - 1;

    }

};

template <bool Enabled>

class AutoAllowTags

{

    Scanner &scanner_;

    bool prev_;

  public:

    AutoAllowTags(Scanner &scanner)

      : scanner_(scanner),

        prev_(scanner_.tagsEnabled())

    {

        scanner_.setTagsEnabled(Enabled);

    }

    ~AutoAllowTags()

    {

        scanner_.setTagsEnabled(prev_);

    }

};

} // namespace ke

#endif // _include_jitcraft_scanner_h_