/**
 *  Copyright (C) 2010 Cloud.com, Inc.  All rights reserved.
 * 
 * This software is licensed under the GNU General Public License v3 or later.
 * 
 * It is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or any later version.
 * 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * 
 */
package com.cloud.maint;

import com.cloud.utils.component.Manager;

/**
 * Upgrade Manager manages the upgrade of agents.
 *
 */
public interface UpgradeManager extends Manager {
    enum State {
        RequiresUpdate,
        WaitingForUpdate,
        UpToDate;
    };
    
    /**
     * Checks if the agent requires an upgrade before it can process
     * any commands.
     * 
     * @param hostId host id.
     * @param version version of the host.
     * @return state of the agent.
     */
    State registerForUpgrade(long hostId, String version);
    
    /**
     * @return the URL to download the new agent.
     */
//    String getAgentUrl();
    

}