// 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.hypervisor;

import com.cloud.agent.api.Command;
import com.cloud.agent.api.to.VirtualMachineTO;
import com.cloud.hypervisor.Hypervisor.HypervisorType;
import com.cloud.utils.component.Adapter;
import com.cloud.vm.VirtualMachine;
import com.cloud.vm.VirtualMachineProfile;

public interface HypervisorGuru extends Adapter {
    HypervisorType getHypervisorType();
    
    /**
     * Convert from a virtual machine to the
     * virtual machine that the hypervisor expects. 
     * @param vm 
     * @return
     */
    <T extends VirtualMachine> VirtualMachineTO implement(VirtualMachineProfile<T> vm);
    
    /**
     * Give hypervisor guru opportunity to decide if certain command needs to be delegated to other host, mainly to secondary storage VM host
     * @param hostId original hypervisor host
     * @param cmd command that is going to be sent, hypervisor guru usually needs to register various context objects into the command object
     * 
     * @return delegated host id if the command will be delegated
     */
    long getCommandHostDelegation(long hostId, Command cmd);
    
    /**
     *  @return true if VM can be migrated independently with CloudStack, and therefore CloudStack needs to track and reflect host change
     *  into CloudStack database, false if CloudStack enforces VM sync logic
     *  
     */
    boolean trackVmHostChange();
}