using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
using EPiServer.Security;
using EPiServer.Web.Routing;
using EPiServer.Web;
using System.Web;
using System.Reflection;
using personalization = EPiServer.Personalization.VisitorGroups;
using EPiServer.ServiceLocation;
using EPiServer.Personalization.VisitorGroups;
using EPiServer.Web.Routing.Segments.Internal;

namespace AlloyTraining.Custom.VisitorGroup
{
	public class ForceVisitorGroupCheckAttribute : ActionFilterAttribute
	{
		/// <summary>
		/// Called before the controller action is executed.
		/// </summary>
		/// <param name="filterContext">The filter context.</param>
		public override void OnActionExecuting(ActionExecutingContext filterContext)
		{
			var visitorGroupKeyByID = "visitorgroupsByID";
			var httpContext = filterContext.HttpContext;
			var contextMode = RequestSegmentContext.CurrentContextMode;

			if (httpContext.Request.QueryString[visitorGroupKeyByID] == null && contextMode.EditOrPreview())
			{
				var visitorGroupIds = GetVisitorGroupIdsByCurrentUser();

				UpdateQueryString(httpContext, visitorGroupKeyByID, String.Join("|", visitorGroupIds.ToArray()));
			}

			base.OnActionExecuting(filterContext);
		}
		private List<string> GetVisitorGroupIdsByCurrentUser()
		{
			List<string> visitorGroupID = new List<string>();

			var visitorGroupRepository = ServiceLocator.Current.GetInstance<IVisitorGroupRepository>();
			var visitorGroupRoleRepository = ServiceLocator.Current.GetInstance<IVisitorGroupRoleRepository>();
			var httpContextAccessor = ServiceLocator.Current.GetInstance<ServiceAccessor<HttpContextBase>>();

			var httpContext = httpContextAccessor();
			var user = httpContext.User;
			var visitorGroups = visitorGroupRepository.List();
			foreach (var visitorGroup in visitorGroups)
			{
				VisitorGroupRole virtualRoleObject;
				if (visitorGroupRoleRepository.TryGetRole(visitorGroup.Name, out virtualRoleObject))
				{
					if (virtualRoleObject.IsMatch(user, httpContext))
					{
						visitorGroupID.Add(visitorGroup.Id.ToString());
					}
				}
			}

			return visitorGroupID;
		}
		private void UpdateQueryString(HttpContextBase context, string queryString, string value)
		{
			PropertyInfo isreadonly = typeof(System.Collections.Specialized.NameValueCollection).GetProperty("IsReadOnly", BindingFlags.Instance | BindingFlags.NonPublic);
			isreadonly.SetValue(context.Request.QueryString, false, null);
			context.Request.QueryString.Set(queryString, value);
			isreadonly.SetValue(context.Request.QueryString, true, null);
		}
	}
}