/**
 *    Copyright (C) 2015 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.
 */

#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kCommand

#include "mongo/platform/basic.h"

#include "mongo/db/commands.h"
#include "mongo/s/client/shard_registry.h"
#include "mongo/s/grid.h"
#include "mongo/s/request_types/add_shard_request_type.h"
#include "mongo/util/log.h"
#include "mongo/util/scopeguard.h"

namespace mongo {
namespace {

const ReadPreferenceSetting kPrimaryOnlyReadPreference{ReadPreference::PrimaryOnly};
const char kShardAdded[] = "shardAdded";

class AddShardCmd : public BasicCommand {
public:
    AddShardCmd() : BasicCommand("addShard", "addshard") {}

    AllowedOnSecondary secondaryAllowed(ServiceContext*) const override {
        return AllowedOnSecondary::kAlways;
    }

    bool adminOnly() const override {
        return true;
    }

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

    std::string help() const override {
        return "add a new shard to the system";
    }

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

    bool run(OperationContext* opCtx,
             const std::string& dbname,
             const BSONObj& cmdObj,
             BSONObjBuilder& result) override {
        auto parsedRequest = uassertStatusOK(AddShardRequest::parseFromMongosCommand(cmdObj));

        auto configShard = Grid::get(opCtx)->shardRegistry()->getConfigShard();

        // Force a reload of this node's shard list cache at the end of this command.
        auto cmdResponseWithStatus = configShard->runCommandWithFixedRetryAttempts(
            opCtx,
            kPrimaryOnlyReadPreference,
            "admin",
            CommandHelpers::appendMajorityWriteConcern(CommandHelpers::appendPassthroughFields(
                cmdObj, parsedRequest.toCommandForConfig())),
            Shard::RetryPolicy::kIdempotent);

        if (!Grid::get(opCtx)->shardRegistry()->reload(opCtx)) {
            Grid::get(opCtx)->shardRegistry()->reload(opCtx);
        }
        auto cmdResponse = uassertStatusOK(cmdResponseWithStatus);
        CommandHelpers::filterCommandReplyForPassthrough(cmdResponse.response, &result);
        return true;
    }

} addShardCmd;

}  // namespace
}  // namespace mongo