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 *     following disclaimer. 
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 *     following disclaimer in the documentation and/or other 
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 * 
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 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
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using System;
using System.Collections.Generic;
using System.Linq;
using XenAdmin.Core;
using XenAPI;


namespace XenAdmin.Actions.VMActions
{
    public class VMMoveAction : AsyncAction
    {
        public Dictionary<string, SR> StorageMapping;

        public VMMoveAction(VM vm, Dictionary<string, SR> storageMapping, Host host)
            : base(vm.Connection, Messages.ACTION_VM_MOVING)
        {
            this.Description = Messages.ACTION_PREPARING;
            this.VM = vm;
            this.Host = host;
            this.Pool = Helpers.GetPool(vm.Connection);
            if (vm.is_a_template)
                this.Template = vm;

            StorageMapping = storageMapping;
            SR = StorageMapping.Values.FirstOrDefault();

            PopulateApiMethodsToRoleCheck();
        }

        public VMMoveAction(VM vm, SR sr, Host host, string namelabel)
            : base(vm.Connection, string.Format(Messages.ACTION_VM_MOVING_TITLE, vm.Name, namelabel, sr.NameWithoutHost))
        {
            this.Description = Messages.ACTION_PREPARING;
            this.VM = vm;
            this.Host = host;
            this.Pool = Helpers.GetPool(vm.Connection);
            this.SR = sr;
            if (vm.is_a_template)
                this.Template = vm;

            // create a storage map where all VDIs are mapped to the same SR
            StorageMapping = new Dictionary<string, SR>();
            var vbds = vm.Connection.ResolveAll(vm.VBDs);
            foreach (var vbd in vbds)
            {
                StorageMapping.Add(vbd.VDI.opaque_ref, sr);
            }

            PopulateApiMethodsToRoleCheck();
        }

        #region RBAC Dependencies
        private void PopulateApiMethodsToRoleCheck()
        {
            ApiMethodsToRoleCheck.AddRange(Role.CommonSessionApiList);
            ApiMethodsToRoleCheck.AddRange(Role.CommonTaskApiList);
            ApiMethodsToRoleCheck.Add("vm.copy");
            ApiMethodsToRoleCheck.Add("vm.set_name_description");
            ApiMethodsToRoleCheck.Add("vm.set_suspend_SR");
            ApiMethodsToRoleCheck.Add("vm.destroy");
            ApiMethodsToRoleCheck.Add("vdi.destroy");
        }
        #endregion

        protected override void Run()
        {
            this.Description = Messages.ACTION_VM_MOVING;
            try
            {
                var vbds = Connection.ResolveAll(VM.VBDs);
                int halfstep = (int)(90/(vbds.Count * 2));
                // move the progress bar above 0, it's more reassuring to see than a blank bar as we copy the first disk
                PercentComplete += 10;
                Exception exn = null;

                foreach (VBD oldVBD in vbds)
                {
                    if (!oldVBD.IsOwner)
                        continue;

                    SR sr = StorageMapping != null ? StorageMapping[oldVBD.VDI.opaque_ref] : null;

                    var curVdi = Connection.Resolve(oldVBD.VDI);
                    if (curVdi == null || sr == null || curVdi.SR.opaque_ref == sr.opaque_ref)
                        continue;

                    RelatedTask = XenAPI.VDI.async_copy(Session, oldVBD.VDI.opaque_ref, sr.opaque_ref);
                    PollToCompletion(PercentComplete, PercentComplete + halfstep);
                    var newVDI = Connection.WaitForCache(new XenRef<VDI>(Result));
 
                    var newVBD = new VBD
                                     {
                                         IsOwner = oldVBD.IsOwner,
                                         userdevice = oldVBD.userdevice,
                                         bootable = oldVBD.bootable,
                                         mode = oldVBD.mode,
                                         type = oldVBD.type,
                                         unpluggable = oldVBD.unpluggable,
                                         other_config = oldVBD.other_config,
                                         VDI = new XenRef<VDI>(newVDI.opaque_ref),
                                         VM = new XenRef<VM>(VM.opaque_ref)
                                     };

                    VBD vbd = oldVBD;
                    BestEffort(ref exn, () => VDI.destroy(Session, vbd.VDI.opaque_ref));
                    Connection.WaitForCache<VBD>(VBD.create(Session, newVBD));

                    PercentComplete += halfstep;
                }

                if (SR != null)
                    VM.set_suspend_SR(Session, VM.opaque_ref, SR.opaque_ref);

                if (exn != null)
                    throw exn;

            }
            catch (CancelledException)
            {
                this.Description = string.Format(Messages.MOVE_CANCELLED, VM.Name);
                throw;
            }
            this.Description = Messages.MOVED;
        }
    }
}