/**
 *    Copyright (C) 2018-present MongoDB, Inc.
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the Server Side Public License, version 1,
 *    as published by MongoDB, Inc.
 *
 *    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
 *    Server Side Public License for more details.
 *
 *    You should have received a copy of the Server Side Public License
 *    along with this program. If not, see
 *    <http://www.mongodb.com/licensing/server-side-public-license>.
 *
 *    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 Server Side 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/platform/basic.h"

#include "mongo/db/auth/action_set.h"
#include "mongo/db/auth/action_type.h"
#include "mongo/db/auth/privilege.h"
#include "mongo/db/commands.h"
#include "mongo/s/client/shard_registry.h"
#include "mongo/s/grid.h"

namespace mongo {
namespace {

class CmdGetShardMap : public BasicCommand {
public:
    CmdGetShardMap() : BasicCommand("getShardMap") {}


    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
        return false;
    }

    virtual bool slaveOk() const {
        return true;
    }

    virtual void help(std::stringstream& help) const {
        help << "lists the set of shards known to this instance";
    }

    virtual bool adminOnly() const {
        return true;
    }

    virtual void addRequiredPrivileges(const std::string& dbname,
                                       const BSONObj& cmdObj,
                                       std::vector<Privilege>* out) {
        ActionSet actions;
        actions.addAction(ActionType::getShardMap);
        out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
    }

    virtual bool run(OperationContext* opCtx,
                     const std::string& dbname,
                     const BSONObj& cmdObj,
                     BSONObjBuilder& result) {
        // MongoD instances do not know that they are part of a sharded cluster until they
        // receive a setShardVersion command and that's when the catalog manager and the shard
        // registry get initialized.
        if (grid.shardRegistry()) {
            grid.shardRegistry()->toBSON(&result);
        }

        return true;
    }

} getShardMapCmd;

}  // namespace
}  // namespace mongo