/* Copyright (c) Citrix Systems, Inc. 
 * All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, 
 * with or without modification, are permitted provided 
 * that the following conditions are met: 
 * 
 * *   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 
 *     materials provided with the distribution. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
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using System.Collections.Generic;
using XenAdmin.Core;
using XenAdmin.Wlb;
using XenAPI;


namespace XenAdmin.Actions.Wlb
{
    public class WlbEvacuateRecommendationsAction : AsyncAction
    {
        public WlbEvacuateRecommendationsAction(Host host)
            : base(host.Connection, string.Format(Messages.WLB_RETRIEVING_EVACUATE_RECOMMENDATIONS, host.Name()), true)
        {
            Host = host;
        }

        public Dictionary<XenRef<VM>, string[]> CantEvacuateReasons = new Dictionary<XenRef<VM>, string[]>();

        protected override void Run()
        {
            Description = Messages.SCANNING_VMS;

            if (Helpers.WlbEnabled(Connection))
                CantEvacuateReasons = Host.retrieve_wlb_evacuate_recommendations(Session, Host.opaque_ref);

            if (CantEvacuateReasons == null || CantEvacuateReasons.Count == 0 || !ValidRecommendation(CantEvacuateReasons))
                CantEvacuateReasons = Host.get_vms_which_prevent_evacuation(Session, Host.opaque_ref);

            Description = Messages.COMPLETED;
        }

        private bool ValidRecommendation(Dictionary<XenRef<VM>, string[]> reasons)
        {
            List<Host> controlDomain = new List<Host>();

            foreach (KeyValuePair<XenRef<VM>, string[]> kvp in reasons)
            {
                if (Connection.Resolve(kvp.Key).is_control_domain)
                    controlDomain.Add(Connection.Cache.Find_By_Uuid<Host>(kvp.Value[(int)RecProperties.ToHost]));
            }

            foreach (KeyValuePair<XenRef<VM>, string[]> kvp in reasons)
            {
                if (kvp.Value[0].Trim().ToLower() == "wlb")
                {
                    Host toHost = Connection.Cache.Find_By_Uuid<Host>(kvp.Value[(int)RecProperties.ToHost]);
                    if (!Connection.Resolve(kvp.Key).is_control_domain && !toHost.IsLive() && !controlDomain.Contains(toHost))
                    {
                        return false;
                    }
                }
            }

            return true;
        }
    }
}