/BlogEngine/BlogEngine.NET/App_Code/Controls/RecentComments.cs

// --------------------------------------------------------------------------------------------------------------------

// <summary>

//   Builds a category list.

// </summary>

// --------------------------------------------------------------------------------------------------------------------



namespace App_Code.Controls

{

    using System;

    using System.Collections.Generic;

    using System.IO;

    using System.Linq;

    using System.Text.RegularExpressions;

    using System.Web.UI;

    using System.Web.UI.HtmlControls;



    using BlogEngine.Core;



    using Resources;



    /// <summary>

    /// Builds a category list.

    /// </summary>

    public class RecentComments : Control

    {

        #region Constants and Fields



        /// <summary>

        /// The sync root.

        /// </summary>

        private static readonly object syncRoot = new object();



        /// <summary>

        /// The comments.

        /// </summary>

        private static readonly Dictionary<Guid, List<Comment>> blogsComments = new Dictionary<Guid, List<Comment>>();



        #endregion



        #region Constructors and Destructors



        /// <summary>

        /// Initializes static members of the <see cref="RecentComments"/> class.

        /// </summary>

        static RecentComments()

        {

            BindComments();

            Post.CommentAdded += (sender, args) => BindComments();

            Post.CommentRemoved += (sender, args) => BindComments();

            Post.Saved += PostSaved;

            Comment.Approved += (sender, args) => BindComments();

            BlogSettings.Changed += (sender, args) => BindComments();

        }



        #endregion



        #region Properties



        private static List<Comment> Comments

        {

            get

            {

                Guid blogId = Blog.CurrentInstance.Id;



                if (!blogsComments.ContainsKey(blogId))

                {

                    lock (syncRoot)

                    {

                        if (!blogsComments.ContainsKey(blogId))

                        {

                            blogsComments[blogId] = new List<Comment>();

                        }

                    }

                }



                return blogsComments[blogId];

            }

        }



        #endregion



        #region Public Methods



        /// <summary>

        /// Outputs server control content to a provided <see cref="T:System.Web.UI.HtmlTextWriter"/> object and stores tracing information about the control if tracing is enabled.

        /// </summary>

        /// <param name="writer">The <see cref="T:System.Web.UI.HtmlTextWriter"/> object that receives the control content.</param>

        public override void RenderControl(HtmlTextWriter writer)

        {

            if (Post.Posts.Count <= 0)

            {

                return;

            }

            

            var html = RenderComments();

            writer.Write(html);

            writer.Write(Environment.NewLine);

        }



        #endregion



        #region Methods



        /// <summary>

        /// Binds the comments.

        /// </summary>

        private static void BindComments()

        {

                var comments = (from post in Post.Posts

                                where post.IsVisible

                                from comment in post.Comments

                                where comment.IsApproved

                                select comment).ToList();



                comments.Sort();

                comments.Reverse();



                RecentComments.Comments.Clear();

                foreach (var comment in

                    comments.Where(comment => comment.Email != "pingback" && comment.Email != "trackback").Take(BlogSettings.Instance.NumberOfRecentComments))

                {

                    Comments.Add(comment);

                }

        }



        /// <summary>

        /// Handles the Saved event of the Post control.

        /// </summary>

        /// <param name="sender">The source of the event.</param>

        /// <param name="e">The <see cref="BlogEngine.Core.SavedEventArgs"/> instance containing the event data.</param>

        private static void PostSaved(object sender, SavedEventArgs e)

        {

            if (e.Action == SaveAction.Update)

            {

                return;

            }



            BindComments();

        }



        /// <summary>

        /// Renders the comments.

        /// </summary>

        /// <returns>The HTML string.</returns>

        private static string RenderComments()

        {

            if (Comments.Count == 0)

            {

                return string.Format("<p>{0}</p>", labels.none);

            }



            using (var ul = new HtmlGenericControl("ul"))

            {

                ul.Attributes.Add("class", "recentComments");

                ul.ID = "recentComments";



                foreach (var comment in Comments.Where(comment => comment.IsApproved))

                {

                    var li = new HtmlGenericControl("li");



                    // The post title

                    var title = new HtmlAnchor { HRef = comment.Parent.RelativeLink, InnerText = comment.Parent.Title };

                    title.Attributes.Add("class", "postTitle");

                    li.Controls.Add(title);



                    // The comment count on the post

                    var count =

                        new LiteralControl(string.Format(" ({0})<br />", ((Post)comment.Parent).ApprovedComments.Count));

                    li.Controls.Add(count);



                    // The author

                    if (comment.Website != null)

                    {

                        var author = new HtmlAnchor { HRef = comment.Website.ToString(), InnerHtml = comment.Author };

                        author.Attributes.Add("rel", "nofollow");

                        li.Controls.Add(author);



                        var wrote = new LiteralControl(string.Format(" {0}: ", labels.wrote));

                        li.Controls.Add(wrote);

                    }

                    else

                    {

                        var author = new LiteralControl(string.Format("{0} {1}: ", comment.Author, labels.wrote));

                        li.Controls.Add(author);

                    }



                    // The comment body

                    var commentBody = Regex.Replace(comment.Content, @"\[(.*?)\]", string.Empty);

                    var bodyLength = Math.Min(commentBody.Length, 50);



                    commentBody = commentBody.Substring(0, bodyLength);

                    if (commentBody.Length > 0)

                    {

                        if (commentBody[commentBody.Length - 1] == '&')

                        {

                            commentBody = commentBody.Substring(0, commentBody.Length - 1);

                        }

                    }



                    commentBody += comment.Content.Length <= 50 ? " " : "? ";

                    var body = new LiteralControl(commentBody);

                    li.Controls.Add(body);



                    // The comment link

                    var link = new HtmlAnchor

                        {

                            HRef = string.Format("{0}#id_{1}", comment.Parent.RelativeLink, comment.Id), InnerHtml = string.Format("[{0}]", labels.more) 

                        };

                    link.Attributes.Add("class", "moreLink");

                    li.Controls.Add(link);



                    ul.Controls.Add(li);

                }



                using (var sw = new StringWriter())

                {

                    ul.RenderControl(new HtmlTextWriter(sw));

                    return sw.ToString();

                }

            }

        }



        #endregion

    }

}