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 * *   Redistributions of source code must retain the above 
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 *     following disclaimer. 
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 *     copyright notice, this list of conditions and the 
 *     following disclaimer in the documentation and/or other 
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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 System.Text;
using System.Windows.Forms;
using XenAdmin.Core;
using XenAdmin.Dialogs;
using XenAPI;

namespace XenAdmin.Commands
{
    class MigrateVirtualDiskCommand : Command
    {
        /// <summary>
        /// Initializes a new instance of this Command. The parameter-less constructor is required in the derived
        /// class if it is to be attached to a ToolStrip menu item or button. It should not be used in any other scenario.
        /// </summary>
        public MigrateVirtualDiskCommand()
        {
        }

        public MigrateVirtualDiskCommand(IMainWindow mainWindow, IEnumerable<SelectedItem> selection)
            : base(mainWindow, selection)
        {
        }

        public MigrateVirtualDiskCommand(IMainWindow mainWindow, VDI vdi)
            : base(mainWindow, vdi)
        {
        }

        public override string ContextMenuText
        {
            get
            {
                return Messages.MOVE_VDI_CONTEXT_MENU;
            }
        }

        protected override void ExecuteCore(SelectedItemCollection selection)
        {
            List<VDI> vdis = selection.AsXenObjects<VDI>();

            bool featureForbidden = vdis.TrueForAll(vdi => Helpers.FeatureForbidden(vdi.Connection, Host.RestrictCrossPoolMigrate));
            if (featureForbidden)
            {
                ShowUpsellDialog(Parent);
            }
            else
            {
                new VDIMigrateDialog(selection.FirstAsXenObject.Connection, vdis).Show(Program.MainWindow);
            }
        }

        public static void ShowUpsellDialog(IWin32Window parent)
        {
            UpsellDialog dlg = new UpsellDialog(Messages.MIGRATE_VDI_UPSELL_BLURB, InvisibleMessages.UPSELL_LEARNMOREURL_CPM);
            dlg.ShowDialog(parent);
        }

        protected override bool CanExecuteCore(SelectedItemCollection selection)
        {
            return selection.Count >= 1 && selection.All(v=>VDIIsSuitable(v.XenObject as VDI));
        }

        private bool VDIIsSuitable(VDI vdi)
        {
            
            if (vdi == null)
                return false;
            if (vdi.is_a_snapshot)
                return false;
            if (vdi.Locked)
                return false;
            if (vdi.IsHaType)
                return false;
            if(vdi.Connection.ResolveAll(vdi.VBDs).Count < 1)
                return false;
            if(vdi.GetVMs().Any(vm=>!vm.IsRunning))
                return false;
            if (vdi.Connection.Resolve(vdi.SR).HBALunPerVDI)
                return false;
            return true;
        }

        private bool IsOnLocalSR(VDI vdi)
        {
            return vdi.Connection.Resolve(vdi.SR).IsLocalSR; //Is it currently hosted on a local SR
        }

        protected override string GetCantExecuteReasonCore(SelectedItem item)
        {
            VDI vdi = item.XenObject as VDI;
            if (vdi == null)
                return base.GetCantExecuteReasonCore(item);
            if (vdi.is_a_snapshot)
                return Messages.CANNOT_MOVE_VDI_IS_SNAPSHOT;
            if (vdi.Locked)
                return Messages.CANNOT_MOVE_VDI_IN_USE;
            if (vdi.IsHaType)
                return Messages.CANNOT_MOVE_HA_VD;
            if (vdi.IsMetadataForDR)
                return Messages.CANNOT_MOVE_DR_VD;
            if (IsOnLocalSR(vdi))
                return Messages.LOCAL_TO_LOCAL_MOVE;
            if (vdi.Connection.Resolve(vdi.SR).HBALunPerVDI)
                return Messages.UNSUPPORTED_SR_TYPE;

            return base.GetCantExecuteReasonCore(item);
        }
    }
}