using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;
using HeuristicLab.Collections;
using HeuristicLab.Core;
using HeuristicLab.MainForm;
using HeuristicLab.MainForm.WindowsForms;

namespace HeuristicLab.DebugEngine {

  [View("Execution Stack View")]
  [Content(typeof(ExecutionStack), IsDefaultView = true)]
  public partial class ExecutionStackView : AsynchronousContentView {
    public new ExecutionStack Content {
      get { return (ExecutionStack)base.Content; }
      set { base.Content = value; }
    }

    public ExecutionStackView() {
      InitializeComponent();
    }

    protected override void DeregisterContentEvents() {
      Content.CollectionReset -= Content_Changed;
      Content.ItemsAdded -= Content_Changed;
      Content.ItemsRemoved -= Content_Changed;
      Content.ItemsMoved -= Content_Changed;
      Content.ItemsReplaced -= Content_Changed;
      base.DeregisterContentEvents();
    }

    protected override void RegisterContentEvents() {
      base.RegisterContentEvents();
      Content.CollectionReset += Content_Changed;
      Content.ItemsAdded += Content_Changed;
      Content.ItemsRemoved += Content_Changed;
      Content.ItemsMoved += Content_Changed;
      Content.ItemsReplaced += Content_Changed;
    }

    #region Event Handlers (Content)
    void Content_Changed(object sender, CollectionItemsChangedEventArgs<IndexedItem<IOperation>> e) {
      if (InvokeRequired)
        Invoke(new EventHandler<CollectionItemsChangedEventArgs<IndexedItem<IOperation>>>(Content_Changed), sender, e);
      else
        UpdateExecutionStack();
    }


    private void UpdateExecutionStack() {
      if (!suspended) {
        treeView.BeginUpdate();
        treeView.Nodes.Clear();
        int totalNodes = AddStackOperations(treeView.Nodes, ((IEnumerable<IOperation>)Content).Reverse());
        if (treeView.Nodes.Count > 0)
          treeView.TopNode = treeView.Nodes[0];
        treeView.ExpandAll();
        treeView.EndUpdate();
        groupBox.Text = string.Format("Execution Stack ({0})", totalNodes);
      } else {
        groupBox.Text = string.Format("Execution Stack ({0})", CountOperations(Content));
      }
    }

    private int CountOperations(IEnumerable<IOperation> operations) {
      int count = 0;
      foreach (IOperation op in operations) {
        count++;
        OperationCollection ops = op as OperationCollection;
        if (ops != null)
          count += CountOperations(ops);
      }
      return count;
    }

    private int AddStackOperations(TreeNodeCollection nodes, IEnumerable<IOperation> operations) {
      int count = 0;
      foreach (IOperation op in operations) {
        if (op is IAtomicOperation) {
          IAtomicOperation atom = op as IAtomicOperation;
          TreeNode node = nodes.Add(atom.Operator.Name);
          node.Tag = atom;
          node.ToolTipText = Utils.TypeName(atom.Operator);
          node.ImageKey = "AtomicOperation";
          if (atom.Operator.Breakpoint)
            node.ForeColor = Color.Red;
          count++;
        } else if (op is OperationCollection) {
          OperationCollection ops = op as OperationCollection;
          TreeNode node = treeView.Nodes.Add(
            string.Format("{0} Operation{1}", ops.Count, ops.Count == 1 ? string.Empty : "s"));
          node.Tag = op;
          node.ToolTipText = Utils.TypeName(ops);
          node.ImageKey = "OperationCollection";
          count += AddStackOperations(node.Nodes, ops);
        }
      }
      return count;
    }
    #endregion

    protected override void OnContentChanged() {
      base.OnContentChanged();
      if (Content == null) {
        treeView.Nodes.Clear();
      } else {
        UpdateExecutionStack();
      }
    }


    protected override void SetEnabledStateOfControls() {
      base.SetEnabledStateOfControls();
    }



    #region Event Handlers (child controls)
    private void treeView_NodeMouseDoubleClick(object sender, TreeNodeMouseClickEventArgs e) {
      if (e.Node != null) {
        IAtomicOperation op = e.Node.Tag as IAtomicOperation;
        if (op != null)
          MainFormManager.MainForm.ShowContent(op.Operator);
      }
    }
    #endregion

    #region Suspension
    private bool suspended = false;
    public virtual void SuspendUpdate() {
      suspended = true;
      treeView.Nodes.Clear();
    }

    public virtual void ResumeUpdate() {
      suspended = false;
      UpdateExecutionStack();
    }
    #endregion
  }
}