/* 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 
 *     copyright notice, this list of conditions and the 
 *     following disclaimer. 
 * *   Redistributions in binary form must reproduce the above 
 *     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 
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE.
 */

using System;
using System.Collections.Generic;
using XenAdmin.Actions;
using XenAPI;
using XenAdmin.Network;
using XenAdmin.Model;

namespace XenAdmin.Core
{
    public class HealthCheck
    {
        public static event Action<bool> CheckForAnalysisResultsCompleted;

        /// <summary>
        /// Checks the analysis results for all connections.
        /// Will only perform the check for the connection that have sufficient rights; will not show the action progress.
        /// </summary>
        public static void CheckForAnalysisResults()
        {
            List<AsyncAction> actions = new List<AsyncAction>();
            foreach (IXenConnection xenConnection in ConnectionsManager.XenConnectionsCopy)
            {
                var action = GetAction(xenConnection, true);
                if (action != null)
                    actions.Add(action);
            }

            if (actions.Count == 1)
            {
                actions[0].Completed += actionCompleted;
                actions[0].RunAsync();
            }
            else if (actions.Count > 1)
            {
                var parallelAction = new ParallelAction(string.Empty, string.Empty, string.Empty, actions,
                    suppressHistory: true, showSubActionsDetails: true);
                parallelAction.Completed += actionCompleted;
                parallelAction.RunAsync();
            }
        }

        /// <summary>
        /// Checks the analysis results for the specified connections. 
        /// Will only perform the check if the connection has sufficient rights; will not show the action progress.
        /// </summary>
        public static void CheckForAnalysisResults(object connection)
        {
            CheckForAnalysisResults(connection, true);
        }
        
        /// <summary>
        /// Checks the analysis results for the specified connections.
        /// Will only perform the check if the connection has sufficient rights; If suppressHistory is false, it will show the action progress.
        /// </summary>
        public static void CheckForAnalysisResults(object connection, bool suppressHistory)
        {
            var action = GetAction((IXenConnection)connection, suppressHistory);
            if (action != null)
            {
                action.Completed += actionCompleted;
                action.RunAsync();
            }
        }

        private static AsyncAction GetAction(IXenConnection connection, bool suppressHistory)
        {
            Pool pool = Helpers.GetPoolOfOne(connection);
            if (pool == null || Helpers.FeatureForbidden(connection, Host.RestrictHealthCheck))
                return null;

            var healthCheckSettings = pool.HealthCheckSettings();

            if (healthCheckSettings.Status == HealthCheckStatus.Enabled && !healthCheckSettings.HasAnalysisResult)
            {
                if (PassedRbacChecks(pool.Connection))
                    return new GetHealthCheckAnalysisResultAction(pool, Registry.HealthCheckDiagnosticDomainName, suppressHistory);
            }
            return null;
        }

        public static bool PassedRbacChecks(IXenConnection connection)
        {
            return Role.CanPerform(new RbacMethodList("pool.set_health_check_config"), connection, out _);
        }

        private static void actionCompleted(ActionBase sender)
        {
            Program.AssertOffEventThread();

            GetHealthCheckAnalysisResultAction action = sender as GetHealthCheckAnalysisResultAction;
            if (action == null)
                return;

            if (CheckForAnalysisResultsCompleted != null)
                CheckForAnalysisResultsCompleted(action.Succeeded);
        }

        public static void SendProxySettingsToHealthCheck()
        {
            new TransferProxySettingsAction(
                (HTTPHelper.ProxyStyle)Properties.Settings.Default.ProxySetting,
                Properties.Settings.Default.ProxyAddress,
                Properties.Settings.Default.ProxyPort,
                Properties.Settings.Default.ConnectionTimeout,
                true,
                Properties.Settings.Default.BypassProxyForServers,
                Properties.Settings.Default.ProvideProxyAuthentication,
                Properties.Settings.Default.ProxyUsername,
                Properties.Settings.Default.ProxyPassword,
                (HTTP.ProxyAuthenticationMethod)Properties.Settings.Default.ProxyAuthenticationMethod).RunAsync();
        }

        /// <summary>
        /// Sends XenCenter metadata to the Health Check service; will not show the action progress.
        /// </summary>
        public static void SendMetadataToHealthCheck()
        {
            if (Program.Exiting)
                return;
            var metadata = XenAdminConfigManager.Provider.GetXenCenterMetadata(false);
            if (!string.IsNullOrEmpty(metadata))
            {
                new TransferXenCenterMetadataAction(metadata, true).RunAsync();
            }
        }


    }
}