using System;
using System.IO;
using System.Web.Mvc;
using Umbraco.Core.Logging;
using Umbraco.Core.Models;
using Umbraco.Web.Models;
using Umbraco.Web.Routing;

namespace Umbraco.Web.Mvc
{
	public class RenderMvcController : Controller
	{

		public RenderMvcController()
		{
			ActionInvoker = new RenderActionInvoker();
		}
		
		private PublishedContentRequest _publishedContentRequest;

		/// <summary>
		/// Returns the current UmbracoContext
		/// </summary>
		protected UmbracoContext UmbracoContext
		{
			get { return PublishedContentRequest.RoutingContext.UmbracoContext; }
		}

        /// <summary>
        /// Returns the Current published content item for rendering the content
        /// </summary>
	    protected IPublishedContent CurrentPage
	    {
	        get { return PublishedContentRequest.PublishedContent; }
	    }

		//TODO: make this protected once we make PublishedContentRequest not internal after we figure out what it should actually contain
		/// <summary>
		/// Returns the current PublishedContentRequest
		/// </summary>
		internal PublishedContentRequest PublishedContentRequest
		{
			get
			{
				if (_publishedContentRequest != null)
					return _publishedContentRequest;
				if (!RouteData.DataTokens.ContainsKey("umbraco-doc-request"))
				{
					throw new InvalidOperationException("DataTokens must contain an 'umbraco-doc-request' key with a PublishedContentRequest object");
				}
				_publishedContentRequest = (PublishedContentRequest) RouteData.DataTokens["umbraco-doc-request"];
				return _publishedContentRequest;
			}
		}
		
		/// <summary>
		/// Checks to make sure the physical view file exists on disk
		/// </summary>
		/// <param name="template"></param>
		/// <returns></returns>
		protected bool EnsurePhsyicalViewExists(string template)
		{
			if (!System.IO.File.Exists(
				Path.Combine(Server.MapPath(Constants.ViewLocation), template + ".cshtml")))
			{
				LogHelper.Warn<RenderMvcController>("No physical template file was found for template " + template);
				return false;
			}
			return true;
		}

		/// <summary>
		/// Returns an ActionResult based on the template name found in the route values and the given model.
		/// </summary>
		/// <typeparam name="T"></typeparam>
		/// <param name="model"></param>
		/// <returns></returns>
		/// <remarks>
		/// If the template found in the route values doesn't physically exist, then an empty ContentResult will be returned.
		/// </remarks>
		protected ActionResult CurrentTemplate<T>(T model)
		{
			var template = ControllerContext.RouteData.Values["action"].ToString();
			if (!EnsurePhsyicalViewExists(template))
			{
				return Content("");
			}
			return View(template, model);
		}

		/// <summary>
		/// The default action to render the front-end view
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public virtual ActionResult Index(RenderModel model)
		{
			return CurrentTemplate(model);
		}

	}
}