// expression.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/db/matcher/expression.h"

#include "mongo/bson/bsonmisc.h"
#include "mongo/bson/bsonobj.h"

namespace mongo {

using std::string;

MatchExpression::MatchExpression(MatchType type) : _matchType(type) {}

string MatchExpression::toString() const {
    StringBuilder buf;
    debugString(buf, 0);
    return buf.str();
}

void MatchExpression::_debugAddSpace(StringBuilder& debug, int level) const {
    for (int i = 0; i < level; i++)
        debug << "    ";
}

bool MatchExpression::matchesBSON(const BSONObj& doc, MatchDetails* details) const {
    BSONMatchableDocument mydoc(doc);
    return matches(&mydoc, details);
}

void MatchExpression::setCollator(const CollatorInterface* collator) {
    for (size_t i = 0; i < numChildren(); ++i) {
        getChild(i)->setCollator(collator);
    }

    _doSetCollator(collator);
}

void FalseMatchExpression::debugString(StringBuilder& debug, int level) const {
    _debugAddSpace(debug, level);
    debug << "$all: []\n";
}

void FalseMatchExpression::serialize(BSONObjBuilder* out) const {
    // Our query language has no "always false" operator aside from a $all with no children, so use
    // that as a proxy here.
    BSONObjBuilder child(out->subobjStart(_path));
    BSONArrayBuilder allChild(child.subarrayStart("$all"));
    allChild.doneFast();
    child.doneFast();
}
}
