// -*- mode: c++; c-basic-offset:4 -*-

// This file is part of libdap, A C++ implementation of the OPeNDAP Data

// Access Protocol.

// Copyright (c) 2011 OPeNDAP, Inc.

// Author: James Gallagher <jgallagher@opendap.org>

//

// This library is free software; you can redistribute it and/or

// modify it under the terms of the GNU Lesser General Public

// License as published by the Free Software Foundation; either

// version 2.1 of the License, or (at your option) any later version.

//

// This library 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

// Lesser General Public License for more details.

//

// You should have received a copy of the GNU Lesser General Public

// License along with this library; if not, write to the Free Software

// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

//

// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.

#ifndef KEYWORDS_H_

#define KEYWORDS_H_

#include <string>

#include <set>

#include <map>

#include <list>

using namespace std;

namespace libdap {

/**

 * Manage keywords for libdap. These are passed in to the library using the

 * constraint expression - in fact they are an extension of the CE and this

 * class implements the parsing needed to remove them from the CE so that

 * the ConstraintExpression evaluator can parse it (because the keywords are

 * not identifiers in the DDS, they will cause a parse error.

 *

 * @note If pointers are added to this code, modify DDS so copying still works!

 *

 * @note The keywords are used to specify the DAP version(s) that the client

 * can understand.

 *

 * @note Keywords are parsed and used by the BES in Hyrax - libdap never makes

 * calls to these methods.

 */

class Keywords {

public:

    // convenience types

    typedef string keyword;

    typedef string keyword_value;

    typedef set<keyword_value> value_set_t;

private:

    /// Holds the keywords and value of the keywords passed in the CE

    map<keyword, keyword_value> d_parsed_keywords;

    /// Holds all of the keywords

    map<keyword, value_set_t> d_known_keywords;

    virtual void m_add_keyword(const keyword &word, const keyword_value &value);

    virtual bool m_is_valid_keyword(const keyword &word, const keyword_value &value) const;

public:

    Keywords();

    virtual ~Keywords();

    virtual string parse_keywords(const string &ce);

    // Is this keyword in the dictionary?

    virtual bool is_known_keyword(const string &s) const;

    // Get a list of all of the keywords parsed

    virtual list<keyword> get_keywords() const;

    // Has a particular keyword been parsed

    virtual bool has_keyword(const keyword &kw) const;

    // Get the parsed keyword (and it's dictionary value) of a particular kind

    virtual keyword_value get_keyword_value(const keyword &kw) const;

};

}

#endif /* KEYWORDS_H_ */