Spark caching

SparkLoader.cs

using System.Collections.Generic;
using System.Linq;
using Spark;
using Spark.Compiler;
using Spark.Web.FubuMVC;
using Spark.Web.FubuMVC.ViewCreation;
using Spark.Web.FubuMVC.ViewLocation;

namespace ZG.Mvc.Theming.Views.Spark
{
    public class SparkLoader
    {
        private readonly SparkViewFactory _sparkViewFactory;
        private readonly ActionContext _actionContext;
        private static readonly IDictionary<BuildDescriptorParams, ISparkViewEntry> _cache;

        static SparkLoader()
        {
            _cache = new Dictionary<BuildDescriptorParams, ISparkViewEntry>();
        }

        public SparkLoader(SparkViewFactory sparkViewFactory, ActionContext actionContext)
        {
            _sparkViewFactory = sparkViewFactory;
            _actionContext = actionContext;
        }

        public virtual SparkView LoadPartial(string path)
        {
            var descriptorParams = getDescriptorParams(path, null);
            var viewEntry = findViewEntry(descriptorParams);
            var view = buildResult(viewEntry);
            return (SparkView)view;
        }

        public virtual SparkView LoadView(string path, string master)
        {
            var descriptorParams = getDescriptorParams(path, master);
            var viewEntry = findViewEntry(descriptorParams);
            var view = buildResult(viewEntry);
            return (SparkView)view;
        }

        private BuildDescriptorParams getDescriptorParams(string path, string master)
        {
            var parameters = _sparkViewFactory.DescriptorBuilder.GetExtraParameters(_actionContext);
            var actionNamespace = _actionContext.ActionNamespace;
            var actionName = _actionContext.ActionName;
            return new BuildDescriptorParams(actionNamespace, actionName, path, master, false, parameters);
        }

        private ISparkViewEntry findViewEntry(BuildDescriptorParams descriptorParams)
        {
            ISparkViewEntry viewEntry;
            //TODO: IMPLEMENT A SMARTER LOCKING MECHANISM HERE
            lock (_cache)
            {
                if (_cache.TryGetValue(descriptorParams, out viewEntry))
                {
                    // We have the entry in cache, but it has changed, we must invalidate the cache
                    if (!viewEntry.IsCurrent())
                    {
                        _cache.Remove(descriptorParams);
                        viewEntry = createViewEntry(descriptorParams);
                        _cache.Add(descriptorParams, viewEntry);
                    }
                }
                else
                {
                    viewEntry = createViewEntry(descriptorParams);
                    _cache.Add(descriptorParams, viewEntry);
                }
            }
            return viewEntry;
        }

        private ISparkViewEntry createViewEntry(BuildDescriptorParams descriptorParams)
        {
            var searchedLocations = new List<string>();
            var descriptor = _sparkViewFactory.DescriptorBuilder.BuildDescriptor(descriptorParams, searchedLocations);
            var viewEntry = _sparkViewFactory.Engine.CreateEntry(descriptor);
            return viewEntry;
        }

        private ISparkView buildResult(ISparkViewEntry entry)
        {
            var view = entry.CreateInstance();
            if (view is SparkView)
            {
                var sparkView = (SparkView)view;
                sparkView.ResourcePathManager = _sparkViewFactory.Engine.ResourcePathManager;
                sparkView.CacheService = _sparkViewFactory.CacheServiceProvider.GetCacheService();
            }
            return view;
        }

    }
}