// expression_text.cpp

/**
 *    Copyright (C) 2013 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program 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 Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#include "mongo/pch.h"
#include "mongo/db/matcher/expression_text.h"

namespace mongo {

    Status TextMatchExpression::init( const string& query, const string& language ) {
        _query = query;
        _language = language;
        return initPath( "_fts" );
    }

    bool TextMatchExpression::matchesSingleElement( const BSONElement& e ) const {
        // See ops/update.cpp.
        // This node is removed by the query planner.  It's only ever called if we're getting an
        // elemMatchKey.
        return true;
    }

    void TextMatchExpression::debugString( StringBuilder& debug, int level ) const {
        _debugAddSpace(debug, level);
        debug << "TEXT : query=" << _query << ", language=" << _language << ", tag=";
        MatchExpression::TagData* td = getTag();
        if ( NULL != td ) {
            td->debugString( &debug );
        }
        else {
            debug << "NULL";
        }
        debug << "\n";
    }

    void TextMatchExpression::toBSON(BSONObjBuilder* out) const {
        out->append("$text", BSON("$search" << _query << "$language" << _language));
    }

    bool TextMatchExpression::equivalent( const MatchExpression* other ) const {
        if ( matchType() != other->matchType() ) {
            return false;
        }
        const TextMatchExpression* realOther = static_cast<const TextMatchExpression*>( other );

        // TODO This is way too crude.  It looks for string equality, but it should be looking for
        // common parsed form
        if ( realOther->getQuery() != _query ) {
            return false;
        }
        if ( realOther->getLanguage() != _language ) {
            return false;
        }
        return true;
    }

    LeafMatchExpression* TextMatchExpression::shallowClone() const {
        TextMatchExpression* next = new TextMatchExpression();
        next->init( _query, _language );
        if ( getTag() ) {
            next->setTag( getTag()->clone() );
        }
        return next;
    }

}
