// Copyright 2012 Citrix Systems, Inc. Licensed under the
// Apache License, Version 2.0 (the "License"); you may not use this
// file except in compliance with the License.  Citrix Systems, Inc.
// reserves all rights not expressly granted by the License.
// You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// 
// Automatically generated by addcopyright.py at 04/03/2012
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.
     * @return state of the agent.
     */
    State registerForUpgrade(long hostId, String version);
    
    /**
     * @return the URL to download the new agent.
     */
//    String getAgentUrl();
    

}