using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Xml.Linq;

using AshMind.Web.Snapshots.Handlers;

namespace AshMind.Web.Snapshots.Provider {
    // This is somewhat ugly, but is made for a very special task.
    // So I followed JFHCI.
    public class AshMindSnapshotHandler : SnapshotHandler {
        private static readonly string AllowedUrlsFilePath = "~/AllowedUrlList.xml";
        private static readonly HashSet<Uri> AllowedUrls = new HashSet<Uri>();
        
        static AshMindSnapshotHandler() {
            AllowedUrlsFilePath = HttpContext.Current.Server.MapPath(AllowedUrlsFilePath);

            var xml = XDocument.Load(AllowedUrlsFilePath);
            AllowedUrls = new HashSet<Uri>(
                xml.Element("Urls")
                   .Elements("Url")
                   .Select(x => x.Attribute("Value").Value)
                   .Select(value => new Uri(value))
            );
        }

        protected override bool IsUriAllowed(Uri uri) {
            return base.IsUriAllowed(uri) && AllowedUrls.Contains(uri);
        }
    }
}