Menu.cs :  » Content-Management-Systems-CMS » N2 » N2 » Templates » Mvc » Details » Controls » C# / CSharp Open Source

using System;
using System.Collections.Generic;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using N2.Collections;
using N2.Web.UI;
using System.Web.UI.WebControls;
using System.Text.RegularExpressions;

namespace N2.Templates.Mvc.Details.Controls{
  /// <summary>
  /// A web control that emits a nested list of ul's and li's.
  /// </summary>
  public class Menu : WebControl, IContentTemplate
  {
    private ItemFilter[] filters = null;
    private ContentItem startPage;
    private ContentItem currentItem = null;

    public Menu()
    {
      Filters = new ItemFilter[] { new NavigationFilter() };
    }

    public virtual ContentItem CurrentItem
    {
      get { return currentItem ?? (currentItem = ItemUtility.FindCurrentItem(Parent)); }
      set { currentItem = value; }
    }

    public ContentItem StartPage
    {
      get { return startPage ?? Find.ClosestLanguageRoot; }
      set { startPage = value; }
    }

    [Themeable(true)]
    public bool UseMenuIdentifiers
    {
      get { return (bool)(ViewState["UseMenuIdentifiers"] ?? true); }
      set { ViewState["UseMenuIdentifiers"] = value; }
    }

    [Themeable(true)]
    public string MenuIdentifierPrefix
    {
      get { return (string)(ViewState["MenuIdentifierPrefix"] ?? "menu_"); }
      set { ViewState["MenuIdentifierPrefix"] = value; }
    }


    [Themeable(true)]
    public int StartLevel
    {
      get { return (int)(ViewState["StartLevel"] ?? 1); }
      set { ViewState["StartLevel"] = value; }
    }

    [Themeable(true)]
    public bool BranchMode
    {
      get { return (bool)(ViewState["BranchMode"] ?? true); }
      set { ViewState["BranchMode"] = value; }
    }

    [Themeable(true)]
    public int MaxLevels
    {
      get { return (int)(ViewState["MaxLevels"] ?? int.MaxValue); }
      set { ViewState["MaxLevels"] = value; }
    }

    protected override HtmlTextWriterTag TagKey
    {
      get { return HtmlTextWriterTag.Ul; }
    }

    #region Methods

    protected override void CreateChildControls()
    {
      BuildControlHierarchy(CurrentPage, StartPage);
      
      base.CreateChildControls();
    }
    
    private static HtmlGenericControl CreateAndAdd(Control container, string tagName, string cssClass)
    {
      HtmlGenericControl hgc = new HtmlGenericControl(tagName);
      if(!string.IsNullOrEmpty(cssClass))
        hgc.Attributes["class"] = cssClass;
      container.Controls.Add(hgc);
      return hgc;
    }

    private static bool Contains(IEnumerable<ContentItem> ancestors, ContentItem item)
    {
      foreach (ContentItem ancestor in ancestors)
        if (ancestor == item)
          return true;
      return false;
    }
    
    private void BuildControlHierarchy(ContentItem currentItem, ContentItem startPage)
    {
      if(currentItem == null)
        currentItem = startPage;

      ItemList children = currentItem.GetChildren();
      if (children.Count > 0)
        currentItem = children[0];
      IEnumerable<ContentItem> ancestors = GetAncestors(currentItem, startPage);
      ContentItem startingPoint = GetStartingPoint();
      if(startingPoint != null)
      {
        ItemHierarchyNavigator navigator;
        if (BranchMode)
        {
          navigator = new ItemHierarchyNavigator(new BranchHierarchyBuilder(currentItem, startingPoint), Filters);
        }
        else
        {
          navigator = new ItemHierarchyNavigator(new TreeHierarchyBuilder(startingPoint, MaxLevels), Filters);
        }
        if (navigator.Current != null)
        {
          AddControlsRecursive(this, navigator, CurrentPage, ancestors);
        }
      }
    }

    Dictionary<string, Control> addedControls = new Dictionary<string, Control>();

    private void AddControlsRecursive(Control container, IHierarchyNavigator<ContentItem> ih, ContentItem selectedPage, IEnumerable<ContentItem> ancestors)
    {
      foreach (ItemHierarchyNavigator childHierarchy in ih.Children)
      {
        if (!childHierarchy.Current.IsPage)
          continue;
        
        ContentItem current = childHierarchy.Current;
        
        string _cssClass =
          current == selectedPage
          || string.Equals(current.Url, selectedPage.Url, StringComparison.OrdinalIgnoreCase)
            ? "current"
            : Contains(ancestors, current)
                ? "trail"
                : string.Empty;
        
        HtmlGenericControl li = CreateAndAdd(container, "li", _cssClass);

        if (UseMenuIdentifiers)
        {
          string name = Regex.Replace(current.Name, "[^_0-1a-z]", "", RegexOptions.Compiled | RegexOptions.IgnoreCase);
          if(!addedControls.ContainsKey(name))
          {
            addedControls[current.Name] = li;
            li.Attributes["id"] = MenuIdentifierPrefix + name;
          }
        }

        li.Controls.Add(N2.Web.Link.To(current).ToControl());
        
        HtmlGenericControl ul = new HtmlGenericControl("ul");
        AddControlsRecursive(ul, childHierarchy, selectedPage, ancestors);
        if (ul.Controls.Count > 0)
          li.Controls.Add(ul);
      }
    }

    private ItemFilter[] Filters
    {
      get { return filters; }
      set { filters = value; }
    }

    private ContentItem GetStartingPoint()
    {
      return Find.AncestorAtLevel(StartLevel, Find.EnumerateParents(CurrentPage, StartPage, true), CurrentPage);
    }

    private static IEnumerable<ContentItem> GetAncestors(ContentItem currentItem, ContentItem startPage)
    {
      return Find.EnumerateParents(currentItem, startPage);
    }

    #endregion [rgn]

    #region IPageItemContainer Members

    public ContentItem CurrentPage
    {
      get { return Find.CurrentPage; }
    }

    #endregion
  }
}