/BlogEngine/DotNetSlave.BusinessLogic/Web/HttpHandlers/RatingHandler.cs

namespace BlogEngine.Core.Web.HttpHandlers

{

    using System;

    using System.Web;



    /// <summary>

    /// Receives and records all ratings comming in from the rating control.

    /// </summary>

    public class RatingHandler : IHttpHandler

    {

        #region Properties



        /// <summary>

        ///     Gets a value indicating whether another request can use the <see cref = "T:System.Web.IHttpHandler"></see> instance.

        /// </summary>

        /// <value></value>

        /// <returns>true if the <see cref = "T:System.Web.IHttpHandler"></see> instance is reusable; otherwise, false.</returns>

        public bool IsReusable

        {

            get

            {

                return false;

            }

        }



        #endregion



        #region Implemented Interfaces



        #region IHttpHandler



        /// <summary>

        /// Enables processing of HTTP Web requests by a custom HttpHandler that 

        ///     implements the <see cref="T:System.Web.IHttpHandler"></see> interface.

        /// </summary>

        /// <param name="context">

        /// An <see cref="T:System.Web.HttpContext"></see> 

        ///     object that provides references to the intrinsic server objects 

        ///     (for example, Request, Response, Session, and Server) used to service HTTP requests.

        /// </param>

        public void ProcessRequest(HttpContext context)

        {



            if (!BlogSettings.Instance.EnableRating || !Security.IsAuthorizedTo(Rights.SubmitRatingsOnPosts))

            {

                throw new System.Security.SecurityException();

            }

            else

            {

                var rating = context.Request.QueryString["rating"];

                int rate;

                if (rating != null && int.TryParse(rating, out rate))

                {

                    var id = context.Request.QueryString["id"];

                    if (id != null && id.Length == 36 && rate > 0 && rate < 6)

                    {

                        try

                        {

                            if (HasRated(id))

                            {

                                context.Response.Write(string.Format("{0}HASRATED", rate));

                                context.Response.End();

                            }

                            else

                            {

                                var post = Post.GetPost(new Guid(id));

                                post.Rate(rate);



                                SetCookie(id, context);

                                context.Response.Write(string.Format("{0}OK", rate));

                                context.Response.End();

                            }



                        }

                        catch(Exception)

                        {

                           

                            // Something failed.

                        }

                    }

                }

                context.Response.Write("FAIL");

            }

        }



        #endregion



        #endregion



        #region Methods



        /// <summary>

        /// Determines whether the specified post id has rated.

        /// </summary>

        /// <param name="postId">The post id.</param>

        /// <returns>

        ///     <c>true</c> if the specified post id has rated; otherwise, <c>false</c>.

        /// </returns>

        private static bool HasRated(string postId)

        {

            // This seems like a bad idea. Someone without cookies disabled

            // they could repeatedly rate a post. Also, if someone rates

            // a lot of posts, it's going to continue to increase the size

            // of their rating cookie, increasing bandwidth.

            //

            // -rossisdead 10/28/2010

            var ratingCookie = HttpContext.Current.Request.Cookies["rating"];



            if (ratingCookie != null)

            {

                return ratingCookie.Value.Contains(postId);

            }



            return false;

        }



        /// <summary>

        /// Sets the cookie.

        /// </summary>

        /// <param name="id">The cookie id.</param>

        /// <param name="context">The context.</param>

        private static void SetCookie(string id, HttpContext context)

        {

            var cookie = context.Request.Cookies["rating"] ?? new HttpCookie("rating");



            cookie.Expires = DateTime.Now.AddYears(2);

            cookie.Value += id;

            context.Response.Cookies.Add(cookie);

        }



        #endregion

    }

}