/**
 *    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.
 */

#pragma once

#include "mongo/db/write_concern_options.h"
#include "mongo/util/net/hostandport.h"

namespace mongo {

    class OperationContext;
    template <typename T> class StatusWith;

    /**
     * If "writeConcern" indicates a durable commit level,
     * marks the RecoveryUnit associated with "txn" appropriately.
     * Provides a hint to the storage engine that
     * particular operations will be waiting for their changes to become durable.
     */
    void setupSynchronousCommit(const WriteConcernOptions& writeConcern,
                                OperationContext* txn);

    /**
     * Attempts to extract a writeConcern from cmdObj.
     * Verifies that the writeConcern is of type Object (BSON type) and
     * that the resulting writeConcern is valid for this particular host.
     */
    StatusWith<WriteConcernOptions> extractWriteConcern(const BSONObj& cmdObj);

    /**
     * Verifies that a WriteConcern is valid for this particular host.
     */
    Status validateWriteConcern( const WriteConcernOptions& writeConcern );

    struct WriteConcernResult {
        WriteConcernResult() {
            reset();
        }

        void reset() {
            syncMillis = -1;
            fsyncFiles = -1;
            wTimedOut = false;
            wTime = -1;
            err = "";
        }

        void appendTo( const WriteConcernOptions& writeConcern, BSONObjBuilder* result ) const;

        int syncMillis;
        int fsyncFiles;

        bool wTimedOut;
        int wTime;
        std::vector<HostAndPort> writtenTo;

        std::string err; // this is the old err field, should deprecate
    };

    /**
     * Blocks until the database is sure the specified user write concern has been fulfilled, or
     * returns an error status if the write concern fails.  Does no validation of the input write
     * concern, it is an error to pass this function an invalid write concern for the host.
     *
     * Takes a user write concern as well as the replication opTime the write concern applies to -
     * if this opTime.isNull() no replication-related write concern options will be enforced.
     *
     * Returns result of the write concern if successful.
     * Returns NotMaster if the host steps down while waiting for replication
     * Returns UnknownReplWriteConcern if the wMode specified was not enforceable
     */
    Status waitForWriteConcern( OperationContext* txn,
                                const WriteConcernOptions& writeConcern,
                                const OpTime& replOpTime,
                                WriteConcernResult* result );


} // namespace mongo