using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Threading.Tasks;
using System.Timers;
using System.Windows.Forms;
using HeuristicLab.Clients.Hive.CloudManager.Model;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Core.Views;
using HeuristicLab.MainForm;
using HeuristicLab.MainForm.WindowsForms;
using HeuristicLab.PluginInfrastructure;

namespace HeuristicLab.Clients.Hive.CloudManager.Views {
  [View("Cloud Resources View")]
  [Content(typeof(IItemList<Subscription>), IsDefaultView = true)]
  public partial class CloudResourcesView : ItemView, IDisposable {
    ProgressView progressView;
    private System.Timers.Timer timer = new System.Timers.Timer();
    private int updateInterval = 15000;
    private DateTime dueTime;

    private const int subscriptionImageIndex = 0;
    private const int serviceImageIndex = 1;
    private const int deploymentImageIndex = 2;

    public new IItemList<Subscription> Content {
      get { return (IItemList<Subscription>)base.Content; }
      set { base.Content = value; }
    }

    private IItemList<HostedService> hostedServices;
    public IItemList<HostedService> HostedServices {
      get { return hostedServices; }
      set { hostedServices = value; }
    }

    public CloudResourcesView() {
      InitializeComponent();

      treeCloudResources.ImageList.Images.Add(HeuristicLab.Common.Resources.VSImageLibrary.NewFolder);
      treeCloudResources.ImageList.Images.Add(HeuristicLab.Common.Resources.VSImageLibrary.NetworkCenterLarge);
      treeCloudResources.ImageList.Images.Add(HeuristicLab.Common.Resources.VSImageLibrary.MonitorLarge);

      HostedServices = CloudManagerClient.Instance.HostedServices;
      Content = CloudManagerClient.Instance.Subscriptions;


      CloudManagerClient.Instance.Refreshing += new EventHandler(Instance_Refreshing);
      CloudManagerClient.Instance.Refreshed += new EventHandler(Instance_Refreshed);

      timer.AutoReset = true;
      timer.Interval = 1000;
      timer.Elapsed += PerformUpdate;
      timer.Start();
      dueTime = DateTime.Now.AddMilliseconds(updateInterval);

      //IProgress progress = new Progress();
      //progress.Status = "Restore Subscriptions";
      //progressView = new ProgressView(this, progress);
      //CloudManagerClient.Instance.RestoreSubscriptionsFromUserConfig();
      //progressView.Finish();
    }

    #region Register Content Events
    protected override void DeregisterContentEvents() {
      Content.ItemsAdded -= new Collections.CollectionItemsChangedEventHandler<Collections.IndexedItem<Subscription>>(Content_ItemsAdded);
      Content.ItemsRemoved -= new Collections.CollectionItemsChangedEventHandler<Collections.IndexedItem<Subscription>>(Content_ItemsRemoved);
      base.DeregisterContentEvents();
    }
    protected override void RegisterContentEvents() {
      base.RegisterContentEvents();
      Content.ItemsAdded += new Collections.CollectionItemsChangedEventHandler<Collections.IndexedItem<Subscription>>(Content_ItemsAdded);
      Content.ItemsRemoved += new Collections.CollectionItemsChangedEventHandler<Collections.IndexedItem<Subscription>>(Content_ItemsRemoved);
    }
    #endregion

    /// <summary> 
    /// Clean up any resources being used.
    /// </summary>
    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
    protected override void Dispose(bool disposing) {
      if (disposing && (components != null)) {
        components.Dispose();
        CloudManagerClient.Instance.Refreshing -= new EventHandler(Instance_Refreshing);
        CloudManagerClient.Instance.Refreshed -= new EventHandler(Instance_Refreshed);
        timer.Stop();
        timer.Dispose();
        timer = null;
      }
      CloudManagerClient.Instance.PersistSubscriptionsToUserConfig();
      base.Dispose(disposing);
    }

    private void SetProgressView(IProgress progress) {
      if (InvokeRequired) {
        Invoke(new Action<IProgress>(SetProgressView), progress);
      } else {
        if (progressView == null) {
          progressView = new ProgressView(this, progress);
        } else {
          progressView.Progress = progress;
        }
      }
    }

    private void FinishProgressView() {
      if (InvokeRequired) {
        Invoke(new Action(FinishProgressView));
      } else {
        if (progressView != null) {
          progressView.Finish();
          progressView = null;
          SetEnabledStateOfControls();
        }
      }
    }

    public void Restore() {
      var task = System.Threading.Tasks.Task.Factory.StartNew(RestoreAsync);
      task.ContinueWith((t) => {
        FinishProgressView();
        ErrorHandling.ShowErrorDialog(this, "An error occured while restoring Azure Subscriptions.", t.Exception);
      }, TaskContinuationOptions.OnlyOnFaulted);
      FinishProgressView();
    }

    private void RestoreAsync() {
      IProgress progress = new Progress();
      progress.Status = "Restoring Azure Subscriptions";
      SetProgressView(progress);
      List<Subscription> result = CloudManagerClient.Instance.RestoreSubscriptionsFromUserConfig();
      FinishProgressView();
      foreach (Subscription s in result) this.BeginInvoke((MethodInvoker)delegate() { CloudManagerClient.Instance.Add(s); });
    }

    protected override void SetEnabledStateOfControls() {
      base.SetEnabledStateOfControls();
      if (Content == null || Content.Count == 0) {
        if (this.InvokeRequired) {
          this.BeginInvoke((MethodInvoker)delegate() { SetBtnControlsEnabled(false); });
        } else {
          SetBtnControlsEnabled(false);
        }
      } else {
        if (this.InvokeRequired) {
          this.BeginInvoke((MethodInvoker)delegate() { SetBtnControlsEnabled(true); });
        } else {
          SetBtnControlsEnabled(true);
        }
      }
    }

    private void SetBtnControlsEnabled(bool enabled) {
      btnAddSlaveService.Enabled = enabled;
      btnDelete.Enabled = enabled;
      btnSave.Enabled = enabled;
    }

    protected override void OnContentChanged() {
      base.OnContentChanged();
      SetEnabledStateOfControls();
      if (Content == null) {
        viewHost.Content = null;
        treeCloudResources.Nodes.Clear();
      } else if (treeCloudResources.Nodes.Count == 0) {
        treeCloudResources.BeginUpdate();
        //treeCloudResources.Nodes.Clear();
        foreach (Subscription sub in Content) {
          TreeNode nodeSub = GetTreeNode(sub, sub.SubscriptionName, subscriptionImageIndex);
          foreach (HostedService s in HostedServices) {
            if (s.Subscription.SubscriptionID == sub.SubscriptionID) {
              TreeNode nodeServ = GetTreeNode(s, s.HostedServiceProperties.Label, serviceImageIndex);
              foreach (Deployment d in s.Deployments) {
                TreeNode nodeDepl = GetTreeNode(d, d.Label + " (" + d.DeploymentSlot + ")", deploymentImageIndex);
                nodeServ.Nodes.Add(nodeDepl);
              }
              nodeSub.Nodes.Add(nodeServ);
            }
          }
          treeCloudResources.Nodes.Add(nodeSub);
        }
        treeCloudResources.EndUpdate();
      } else {
        treeCloudResources.BeginUpdate();
        TreeNodeCollection tncSubs = treeCloudResources.Nodes;

        // Delete treenodes that have no corresponding data in Content and HosteServices
        foreach (TreeNode tnSub in tncSubs) {
          Subscription s = (Subscription)tnSub.Tag;
          int idx = Content.IndexOf(s);
          if (idx == -1) {
            tncSubs.Remove(tnSub);
          } else {
            TreeNodeCollection tncHS = tnSub.Nodes;
            foreach (TreeNode tnHS in tncHS) {
              HostedService hs = (HostedService)tnHS.Tag;
              int idxHS = HostedServices.IndexOf(hs);
              if (idxHS == -1) {
                tncHS.Remove(tnHS);
              } else {
                TreeNodeCollection tncDep = tnHS.Nodes;
                foreach (TreeNode tnDep in tncDep) {
                  Deployment dep = (Deployment)tnDep.Tag;
                  HostedService hsDep = HostedServices[idxHS];
                  int idxDep = hsDep.Deployments.IndexOf(dep);
                  if (idxDep == -1) {
                    tncDep.Remove(tnDep);
                  }
                }
              }
            }
          }
        }

        // Add missing treenodes
        foreach (Subscription sub in Content) {
          bool foundSub = false;
          TreeNode foundSubNode = null;
          foreach (TreeNode tnSub in treeCloudResources.Nodes) {
            if (((Subscription)tnSub.Tag).Equals(sub)) {
              foundSub = true;
              foundSubNode = tnSub;
            }
          }
          TreeNode nodeSub;
          if (!foundSub) {
            nodeSub = GetTreeNode(sub, sub.SubscriptionName, subscriptionImageIndex);
            treeCloudResources.Nodes.Add(nodeSub);
          } else {
            nodeSub = foundSubNode;
          }
          foreach (HostedService s in HostedServices) {
            if (s.Subscription.SubscriptionID == sub.SubscriptionID) {
              bool foundHS = false;
              TreeNode foundHSNode = null;
              foreach (TreeNode tnHS in nodeSub.Nodes) {
                if (((HostedService)tnHS.Tag).Equals(s)) {
                  foundHS = true;
                  foundHSNode = tnHS;
                }
              }
              TreeNode nodeServ;
              if (!foundHS) {
                nodeServ = GetTreeNode(s, s.HostedServiceProperties.Label, serviceImageIndex);
                nodeSub.Nodes.Add(nodeServ);
              } else {
                nodeServ = foundHSNode;
              }
              foreach (Deployment d in s.Deployments) {
                bool foundDep = false;
                TreeNode foundDepNode;
                foreach (TreeNode tnDep in nodeServ.Nodes) {
                  if (((Deployment)tnDep.Tag).Equals(d)) {
                    foundDep = true;
                    foundDepNode = tnDep;
                  }
                }
                TreeNode nodeDepl;
                if (!foundDep) {
                  nodeDepl = GetTreeNode(d, d.Label + " (" + d.DeploymentSlot + ")", deploymentImageIndex);
                  nodeServ.Nodes.Add(nodeDepl);
                } else {
                  // nothing to do
                }
              }
            }
          }
        }
        // ----------------------------
        treeCloudResources.EndUpdate();
      }
    }

    private TreeNode GetTreeNode(Object tag, string text, int imageIndex) {
      TreeNode node = new TreeNode();
      node.Tag = tag;
      node.Text = text;
      node.ImageIndex = imageIndex;
      node.SelectedImageIndex = node.ImageIndex;
      return node;
    }

    private void Instance_Refreshing(object sender, EventArgs e) {
      Debug.WriteLine("Instance_Refreshing");
      //if (treeCloudResources.InvokeRequired) {
      //  treeCloudResources.Invoke((MethodInvoker)delegate { OnContentChanged(); });
      //} else {
      //  OnContentChanged();
      //}
    }

    private void Instance_Refreshed(object sender, EventArgs e) {
      Debug.WriteLine("Instance_Refreshed");
      if (treeCloudResources.InvokeRequired) {
        treeCloudResources.Invoke((MethodInvoker)delegate { OnContentChanged(); });
      } else {
        OnContentChanged();
      }
    }

    private void Content_ItemsRemoved(object sender, Collections.CollectionItemsChangedEventArgs<Collections.IndexedItem<Subscription>> e) {
      OnContentChanged();
    }

    private void Content_ItemsAdded(object sender, Collections.CollectionItemsChangedEventArgs<Collections.IndexedItem<Subscription>> e) {
      OnContentChanged();
    }

    private void PerformUpdate(object sender, ElapsedEventArgs e) {
      TimeSpan timeToRefresh = dueTime - DateTime.Now;

      if (timeToRefresh.Seconds >= 0) {
        this.Invoke((MethodInvoker)delegate { lblRefresh.Text = "Done. " + timeToRefresh.Seconds + "s to next refresh."; });
      } else {
        timer.Stop();
        this.Invoke((MethodInvoker)delegate { lblRefresh.Text = "Refreshing data ..."; });

        CloudManagerClient.Instance.Refresh();

        dueTime = DateTime.Now.AddMilliseconds(updateInterval);
        if (timer != null) {
          timer.Start();
        }
      }
    }

    private void btnAddSubscription_Click(object sender, EventArgs e) {
      using (var form = new AddSubscriptionDialog()) {
        form.ShowDialog();
        if (!form.ErrorOccured) {
          if (form.Subscription != null) {
            Subscription sub = form.Subscription;
            CloudManagerClient.Instance.Add(sub);
          }
        }
      }
    }

    private void btnAddSlaveService_Click(object sender, EventArgs e) {
      // When refreshing subscriptions in the dialog, 
      // discoverservices and safetoconfig properties are always set to false
      // -> work on deep copy
      Cloner cloner = new Cloner();
      IItemList<Subscription> subscriptions = cloner.Clone(Content);
      using (var form = new AddAzureServiceDialog(subscriptions)) {
        form.ShowDialog();

      }
    }

    private void treeCloudResources_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e) {
      viewHost.Content = (IContent)e.Node.Tag;
    }

    private void btnSave_Click(object sender, EventArgs e) {
      if (treeCloudResources.SelectedNode != null) {
        TreeNode tn = treeCloudResources.SelectedNode;
        TreeNode tnParent = tn.Parent;
        Object obj = tn.Tag;
        Object objParent = tnParent.Tag;
        if (obj is Subscription) {
          // CloudManagerClient.Instance.Save((Subscription)obj);
        } else if (obj is HostedService) {
          // nothing to do so far
        } else if (obj is Deployment && objParent is HostedService) {
          HostedService hs = (HostedService)objParent;
          Deployment dep = (Deployment)obj;
          //call async
          CloudManagerClient.Instance.ChangeIntances(dep, hs);
        }
      }
    }

    private void btnDelete_Click(object sender, EventArgs e) {
      if (treeCloudResources.SelectedNode != null) {
        TreeNode tn = treeCloudResources.SelectedNode;
        TreeNode tnParent = tn.Parent;
        Object obj = tn.Tag;
        Object objParent = null;
        if (tnParent != null) {
          objParent = tnParent.Tag;
        }
        viewHost.Content = null;
        if (obj is Subscription) {
          CloudManagerClient.Instance.Delete((Subscription)obj);
        } else if (obj is HostedService) {
          HostedService hs = (HostedService)obj;
          using (var form = new DeleteHostedServiceView(hs)) {
            form.ShowDialog();
          }
        } else if (obj is Deployment && objParent is HostedService) {
          HostedService hs = (HostedService)objParent;
          Deployment dep = (Deployment)obj;
          using (var form = new DeleteDeploymentView(dep, hs)) {
            form.ShowDialog();
          }
        }
      }
    }
  }
}