/* 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 
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 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE.
 */

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Reflection;
using System.Threading;
using log4net;
using XenAdmin.Controls;
using XenAdmin.Diagnostics.Problems;
using XenAdmin.Wizards.PatchingWizard.PlanActions;
using XenAPI;
using XenAdmin.Actions;

namespace XenAdmin.Wizards.PatchingWizard
{
    public partial class PatchingWizard_PatchingPage : XenTabPage
    {
        protected static readonly ILog log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

        private AsyncAction actionManualMode = null;
        private bool _thisPageHasBeenCompleted = false;
        private BackgroundWorker actionsWorker = null;

        public PatchingWizard_PatchingPage()
        {
            InitializeComponent();
        }

        #region Accessors
        public List<Host> SelectedMasters { private get; set; }
        public List<Host> SelectedServers { private get; set; }
        public List<Pool> SelectedPools { private get; set; }
        public UpdateType SelectedUpdateType { private get; set; }
        public Pool_patch Patch { private get; set; }
        public string ManualTextInstructions { private get; set; }
        public bool IsAutomaticMode { private get; set; }
        public string SelectedNewPatch { private get; set; }
        public List<Problem> ProblemsResolvedPreCheck { private get; set; }
        #endregion

        public override string Text
        {
            get
            {
                return Messages.PATCHINGWIZARD_PATCHINGPAGE_TEXT;
            }
        }

        public override string PageTitle
        {
            get
            {
                return Messages.PATCHINGWIZARD_PATCHINGPAGE_TITLE;
            }
        }

        public override string HelpID
        {
            get { return "InstallUpdate"; }
        }

        public override bool EnablePrevious()
        {
            return false;
        }

        private bool _nextEnabled;
        public override bool EnableNext()
        {
            return _nextEnabled;
        }

        private bool _cancelEnabled;
        public override bool EnableCancel()
        {
            return _cancelEnabled;
        }

        public override void PageLoaded(PageLoadedDirection direction)
        {
            base.PageLoaded(direction);

            if (_thisPageHasBeenCompleted)
            {
                actionManualMode = null;
                actionsWorker = null;
                oemWorker = null;
                return;
            }
          
            if (SelectedUpdateType == UpdateType.NewOem)
            {
                InstallOEMUpdates();
                return;
            }

            //if we reach here it's either UpdateType.NewRetail or UpdateType.Existing

            if (!IsAutomaticMode)
            {
                actionManualMode = new ApplyPatchAction(new List<Pool_patch> { Patch }, SelectedServers);
                actionManualMode.Changed += action_Changed;
                actionManualMode.Completed += action_Completed;
                textBoxLog.Text = ManualTextInstructions;
                actionManualMode.RunAsync();
                return;
            }

            _nextEnabled = false;
            OnPageUpdated();

            List<PlanAction> planActions = new List<PlanAction>();

            foreach (Pool pool in SelectedPools)
            {
                List<Pool_patch> poolPatches = new List<Pool_patch>(pool.Connection.Cache.Pool_patches);
                Pool_patch poolPatch = poolPatches.Find(delegate(Pool_patch otherPatch)
                                                                     {
                                                                         if (Patch != null)
                                                                             return otherPatch.uuid == Patch.uuid;
                                                                         return false;
                                                                     });

                List<Host> poolHosts = new List<Host>(pool.Connection.Cache.Hosts);
                Host master = SelectedServers.Find(host => host.IsMaster() && poolHosts.Contains(host));
                if (master != null)
                    planActions.AddRange(CompileActionList(master, poolPatch));
                foreach (Host server in SelectedServers)
                {
                    if (poolHosts.Contains(server))
                    {
                        if (!server.IsMaster())
                        {   
                            // check patch isn't already applied here
                            if (poolPatch.AppliedOn(server) == DateTime.MaxValue)
                                planActions.AddRange(CompileActionList(server, poolPatch));
                        }
                    }
                }
            }
            planActions.Add(new UnwindProblemsAction(ProblemsResolvedPreCheck));

            actionsWorker = new BackgroundWorker();
            actionsWorker.DoWork += new DoWorkEventHandler(PatchingWizardAutomaticPatchWork);
            actionsWorker.WorkerReportsProgress = true;
            actionsWorker.ProgressChanged += new ProgressChangedEventHandler(actionsWorker_ProgressChanged);
            actionsWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(actionsWorker_RunWorkerCompleted);
            actionsWorker.WorkerSupportsCancellation = true;
            actionsWorker.RunWorkerAsync(planActions);
        }
        
        #region oem

        private BackgroundWorker oemWorker = null;
        private void InstallOEMUpdates()
        {
            List<AsyncAction> actions = new List<AsyncAction>();
            progressBar.Maximum = SelectedMasters.Count * 100;
            //Upload the patches using patch-upload to the master
            foreach (Host selectedServer in SelectedMasters)
            {
                AsyncAction action = new UploadPatchAction(selectedServer.Connection, SelectedNewPatch);
                actions.Add(action);
            }

            oemWorker = new BackgroundWorker();
            oemWorker.WorkerReportsProgress = true;
            oemWorker.DoWork += new DoWorkEventHandler(oemWorker_DoWork);
            oemWorker.ProgressChanged += new ProgressChangedEventHandler(oemWorker_ProgressChanged);
            oemWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(oemWorker_RunWorkerCompleted);
            oemWorker.RunWorkerAsync(actions);
        }

        private void oemWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            Exception exception = e.Result as Exception;
            if (exception == null)
            {
                labelTitle.Text = string.Format(Messages.UPDATE_WAS_SUCCESSFULLY_INSTALLED, Messages.OEM);
                pictureBox1.Image = null;
                labelError.Text = Messages.CLOSE_WIZARD_CLICK_FINISH;
            }
            else
            {
                labelTitle.Text = string.Format(Messages.UPDATE_WAS_NOT_COMPLETED, Messages.OEM);
                string errorMessage = string.Format("\r\n{0}", exception.Message);
                textBoxLog.Text += errorMessage;
                labelError.Text = errorMessage;
                pictureBox1.Image = SystemIcons.Error.ToBitmap();
                panel1.Visible = true;
            }
            _nextEnabled = true;
            _cancelEnabled = false;
            _thisPageHasBeenCompleted = true;
            OnPageUpdated();
        }

        private void oemWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            if (e.ProgressPercentage == 0)
            {
                AsyncAction action = (AsyncAction)e.UserState;
                textBoxLog.Text += string.Format(Messages.UPDATES_WIZARD_APPLYING_UPDATE, Messages.OEM,
                                               action.Host.Name);
            }
            else if (e.ProgressPercentage == 1)
                textBoxLog.Text += string.Format("{0}\r\n", Messages.DONE);

        }

        private AutoResetEvent autoResetEvent = new AutoResetEvent(false);
        private int oemActionsDone = 0;
        private void oemWorker_DoWork(object sender, DoWorkEventArgs e)
        {
            List<AsyncAction> actions = (List<AsyncAction>)e.Argument;
            for (int i = 0; i < actions.Count; i++)
            {
                AsyncAction currentAction = actions[i];
                oemWorker.ReportProgress(0, currentAction);
                currentAction.Changed += PatchingWizard_PatchingPage_Changed;
                currentAction.Completed += PatchingWizard_PatchingPage_Completed;
                currentAction.RunAsync();
                autoResetEvent.WaitOne();
                try
                {
                    string result = currentAction.Result;
                    oemWorker.ReportProgress(1, currentAction);
                }
                catch (Exception except)
                {
                    e.Result = except;
                    return;
                }
                oemActionsDone++;
            }


        }

        private void PatchingWizard_PatchingPage_Completed(ActionBase sender)
        {
            autoResetEvent.Set();
        }

        private void PatchingWizard_PatchingPage_Changed(ActionBase sender)
        {
            AsyncAction action = (AsyncAction)sender;
            Program.Invoke(Program.MainWindow, delegate { progressBar.Value = oemActionsDone * 100 + action.PercentComplete; });
        }

        #endregion

        #region manual_mode

        private void action_Completed(ActionBase sender)
        {
            _nextEnabled = true;
            _cancelEnabled = false;
            
            try
            {
                Program.Invoke(Program.MainWindow, FinishedSuccessfully);
            }
            catch (Exception except)
            {
                Program.Invoke(Program.MainWindow, () => FinishedWithErrors(except));
            }
            Program.Invoke(Program.MainWindow, OnPageUpdated);
            _thisPageHasBeenCompleted = true;
        }

        private void action_Changed(ActionBase sender)
        {
            AsyncAction action = (AsyncAction)sender;
            Program.Invoke(Program.MainWindow, delegate { progressBar.Value = action.PercentComplete; });
        }

        #endregion

        #region automatic_mode

        private void actionsWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            if (!actionsWorker.CancellationPending)
            {
                PlanAction action = (PlanAction)e.UserState;
                if (e.ProgressPercentage == 0)
                    textBoxLog.Text += action;
                else
                {
                    textBoxLog.Text += string.Format("{0}\r\n", Messages.DONE);
                    progressBar.Value += e.ProgressPercentage;
                }
            }
        }      

        private void PatchingWizardAutomaticPatchWork(object obj, DoWorkEventArgs doWorkEventArgs)
        {
            List<PlanAction> actionList = (List<PlanAction>)doWorkEventArgs.Argument;
            foreach (PlanAction action in actionList)
            {
                try
                {
                    if (actionsWorker.CancellationPending)
                    {
                        doWorkEventArgs.Cancel = true;
                        return;
                    }
                    this.actionsWorker.ReportProgress(0, action);
                    action.Run();
                    Thread.Sleep(1000);

                    this.actionsWorker.ReportProgress((int)((1.0 / (double)actionList.Count) * 100), action);
                    
                }
                catch (Exception e)
                {

                    log.Error("Failed to carry out plan.", e);
                    log.Debug(actionList);
                    doWorkEventArgs.Result = new Exception(action.Title);
                    break;
                }
            }
        }

        private void actionsWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            if (!e.Cancelled)
            {
                Exception exception = e.Result as Exception;
                if (exception != null)
                {
                    FinishedWithErrors(exception);

                }
                else
                {
                    FinishedSuccessfully();
                }

                progressBar.Value = 100;
                _cancelEnabled = false;
                _nextEnabled = true;
            }
            OnPageUpdated();
            _thisPageHasBeenCompleted = true;

        }

        private List<PlanAction> CompileActionList(Host host, Pool_patch patch)
        {
            List<PlanAction> actions = new List<PlanAction>();

            List<XenRef<VM>> runningVMs = RunningVMs(host, patch);

            if (!host.isOEM)
                actions.Add(new ApplyPatchPlanAction(host, patch));

            if (patch.after_apply_guidance.Contains(after_apply_guidance.restartHost))
            {
                actions.Add(new EvacuateHostPlanAction(host));
                actions.Add(new RebootHostPlanAction(host));
                actions.Add(new BringBabiesBackAction(runningVMs, host, false));
            }

            if (patch.after_apply_guidance.Contains(after_apply_guidance.restartXAPI))
            {
                actions.Add(new RestartAgentPlanAction(host));
            }

            if (patch.after_apply_guidance.Contains(after_apply_guidance.restartHVM))
            {
                actions.Add(new RebootVMsPlanAction(host, RunningHvmVMs(host)));
            }

            if (patch.after_apply_guidance.Contains(after_apply_guidance.restartPV))
            {
                actions.Add(new RebootVMsPlanAction(host, RunningPvVMs(host)));
            }

            return actions;
        }

        private static List<XenRef<VM>> RunningVMs(Host host, Pool_patch patch)
        {
            List<XenRef<VM>> vms = new List<XenRef<VM>>();
            foreach (VM vm in patch.Connection.ResolveAll(host.resident_VMs))
            {
                if (!vm.is_a_real_vm)
                    continue;

                vms.Add(new XenRef<VM>(vm.opaque_ref));
            }
            return vms;
        }

        private static List<XenRef<VM>> RunningHvmVMs(Host host)
        {
            List<XenRef<VM>> vms = new List<XenRef<VM>>();
            foreach (VM vm in host.Connection.ResolveAll(host.resident_VMs))
            {
                if (!vm.IsHVM || !vm.is_a_real_vm)
                    continue;
                vms.Add(new XenRef<VM>(vm.opaque_ref));
            }
            return vms;
        }

        private static List<XenRef<VM>> RunningPvVMs(Host host)
        {
            List<XenRef<VM>> vms = new List<XenRef<VM>>();
            foreach (VM vm in host.Connection.ResolveAll(host.resident_VMs))
            {
                if (vm.IsHVM || !vm.is_a_real_vm)
                    continue;
                vms.Add(new XenRef<VM>(vm.opaque_ref));
            }
            return vms;
        }

        #endregion

        private void FinishedWithErrors(Exception exception)
        {
            labelTitle.Text = string.Format(Messages.UPDATE_WAS_NOT_COMPLETED, Patch.Name);
            string errorMessage = string.Format(Messages.PATCHING_WIZARD_ERROR, exception.Message);
            labelError.Text = errorMessage;
            pictureBox1.Image = SystemIcons.Error.ToBitmap();
            panel1.Visible = true;
        }

        private void FinishedSuccessfully()
        {
            labelTitle.Text = string.Format(Messages.UPDATE_WAS_SUCCESSFULLY_INSTALLED, Patch.Name);
            pictureBox1.Image = null;
            labelError.Text = Messages.CLOSE_WIZARD_CLICK_FINISH;
        }
    }
}