/**
 *    Copyright (C) 2017 MongoDB 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.
 */

#pragma once

#include "mongo/base/string_data.h"
#include "mongo/db/matcher/expression_array.h"

namespace mongo {

/**
 * MatchExpression for internal JSON Schema keywords that validate the number of items in an array.
 */
class InternalSchemaNumArrayItemsMatchExpression : public ArrayMatchingMatchExpression {
public:
    InternalSchemaNumArrayItemsMatchExpression(MatchType type, StringData name)
        : ArrayMatchingMatchExpression(type), _name(name) {}

    virtual ~InternalSchemaNumArrayItemsMatchExpression() {}

    Status init(StringData path, long long numItems) {
        _numItems = numItems;
        return setPath(path);
    }

    void debugString(StringBuilder& debug, int level) const final;

    void serialize(BSONObjBuilder* out) const final;

    bool equivalent(const MatchExpression* other) const final;

    size_t numChildren() const final {
        return 0;
    }

    MatchExpression* getChild(size_t i) const final {
        MONGO_UNREACHABLE;
    }

    std::vector<MatchExpression*>* getChildVector() final {
        return nullptr;
    }

protected:
    long long numItems() const {
        return _numItems;
    }

private:
    ExpressionOptimizerFunc getOptimizer() const final {
        return [](std::unique_ptr<MatchExpression> expression) { return expression; };
    }

    StringData _name;
    long long _numItems = 0;
};
}  // namespace mongo
