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 */

using System;
using XenAPI;
using XenAdmin.Core;


namespace XenAdmin.Actions
{
    public class DetachVirtualDiskAction : AsyncAction
    {
        private static readonly log4net.ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        private VDI vdi;
        private VBD vbd;
        private bool takeVDILock = true;

        /// <summary>
        /// Detaches a virtual disk
        /// </summary>
        /// <param name="disk">The VDI to detach</param>
        /// <param name="vm">The VM to detach it from</param>
        /// <param name="takeVDILock">Whether it is necessary to lock the VDI (we may be part of another disk action)</param>
        public DetachVirtualDiskAction(VDI disk, VM vm, bool takeVDILock)
            : base(disk.Connection, string.Format(Messages.ACTION_DISK_DETACHING_TITLE, disk.Name(), vm.Name(), false))
        {
            this.takeVDILock = takeVDILock;
            vdi = disk;
            if (takeVDILock)
                vdi.Locked = true;
            VM = vm;
            VM.Locked = true;
            foreach (VBD v in Connection.ResolveAll(VM.VBDs))
            {
                if (v.VDI.opaque_ref == vdi.opaque_ref)
                {
                    vbd = v;
                    vbd.Locked = true;
                }
            }

            if (vbd != null && vbd.currently_attached)
            {
                ApiMethodsToRoleCheck.AddRange(
                    "VBD.get_allowed_operations",
                    "VBD.async_unplug");
            }

            ApiMethodsToRoleCheck.Add("VBD.async_destroy");
        }

        protected override void Run()
        {
            log.DebugFormat("Detaching VDI '{0}'", Helpers.GetName(vdi));
            Description = Messages.ACTION_DISK_DETACHING;
            try
            {
                if (vbd != null && vbd.currently_attached &&
                    VBD.get_allowed_operations(Session, vbd.opaque_ref).Contains(vbd_operations.unplug))
                {
                    RelatedTask = VBD.async_unplug(Session, vbd.opaque_ref);
                    PollToCompletion(0, 50);
                }
            }
            catch (Exception exn)
            {
                log.Error(exn, exn);
                throw;
            }
            finally
            {
                PercentComplete = 50;
                if(vbd != null)
                    RelatedTask = VBD.async_destroy(Session, vbd.opaque_ref);
                PollToCompletion(51, 100);
            }
            Description = Messages.ACTION_DISK_DETACHED;
            log.DebugFormat("Detached VDI '{0}'", Helpers.GetName(vdi));
        }

        protected override void Clean()
        {
            vbd.Locked = false;
            if (takeVDILock)
                vdi.Locked = false;
            VM.Locked = false;
        }
    }
}