// 
// System.Web.HttpRuntime
//
// Author:
//   Patrik Torstensson (Patrik.Torstensson@labs2.com)
//   Gaurav Vaish (gvaish@iitk.ac.in)
//
using System;
using System.Collections;
using System.Security;
using System.Security.Permissions;
using System.Web.UI;
using System.Web.Utils;
using System.Web.Caching;

namespace System.Web {

	[MonoTODO ("Make corrent right now this is a simple impl to give us a base for testing... the methods here are not complete or valid")]	
	public sealed class HttpRuntime {
		// Security permission helper objects
		private static IStackWalk appPathDiscoveryStackWalk;
		private static IStackWalk ctrlPrincipalStackWalk;
		private static IStackWalk sensitiveInfoStackWalk;
		private static IStackWalk unmgdCodeStackWalk;
		private static IStackWalk unrestrictedStackWalk;
		private static IStackWalk reflectionStackWalk;

		private static HttpRuntime runtime;
		private Cache cache;

		// TODO: Temp to test the framework..
		IHttpHandler   handler;

		static HttpRuntime ()
		{
			appPathDiscoveryStackWalk = null;
			ctrlPrincipalStackWalk    = null;
			sensitiveInfoStackWalk    = null;
			unmgdCodeStackWalk        = null;
			unrestrictedStackWalk     = null;
         
			runtime = new HttpRuntime ();
		}

		public HttpRuntime ()
		{
			Init ();
		}

		private void Init ()
		{
			cache = new Cache ();
		}

		public static IHttpHandler Handler {
			get {
				return runtime.handler;
			}

			set {
				runtime.handler = value;
			}
		}

		public static void ProcessRequest (HttpWorkerRequest Request)
		{
			if (runtime.handler == null) 
				throw new ArgumentException ("No handler");

			// just a test method to test the framework

			HttpContext oContext = new HttpContext (Request);
			runtime.handler.ProcessRequest (oContext);

			oContext.Response.FlushAtEndOfRequest ();
			Request.EndOfRequest ();
		}

		public static Cache Cache {
			get {
				return runtime.cache;
			}
		}      

		[MonoTODO]
		public static string AppDomainAppId {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string AppDomainAppPath {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string AppDomainAppVirtualPath {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string AppDomainId {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string AspInstallDirectory {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string BinDirectory {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string ClrInstallDirectory {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string CodegenDir {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static bool IsOnUNCShare {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static string MachineConfigurationDirectory {
			get {
				throw new NotImplementedException ();
			}
		}

		[MonoTODO]
		public static void Close ()
		{
			throw new NotImplementedException ();
		}

		internal static string FormatResourceString (string key)
		{
			return GetResourceString (key);
		}

		internal static string FormatResourceString (string key, string arg0)
		{
			string format = GetResourceString (key);

			if (format == null)
				return null;
			
			return String.Format (format, arg0);
		}

		[MonoTODO ("FormatResourceString (string, string, string)")]
		internal static string FormatResourceString (string key, string arg0, string type) {
			// String.Format (string, object, object);
			throw new NotImplementedException ();
		}

		[MonoTODO ("FormatResourceString (string, string, string, string)")]
		internal static string FormatResourceString (string key, string arg0,
							     string arg1, string arg2)
		{
			// String.Format (string, object, object, object);
			throw new NotImplementedException ();
		}

		[MonoTODO ("FormatResourceString (string, string[]")]
		internal static string FormatResourceString (string key, string[] args)
		{
			// String.Format (string, object[]);
			throw new NotImplementedException ();
		}

		private static string GetResourceString (string key) {
			return runtime.GetResourceStringFromResourceManager (key);
		}

		[MonoTODO ("GetResourceStringFromResourceManager (string)")]
		private string GetResourceStringFromResourceManager (string key) {
			throw new NotImplementedException ();
		}

		[MonoTODO ("Get Application path from the appdomain object")]
		internal static IStackWalk AppPathDiscovery {
			get {
				if (appPathDiscoveryStackWalk == null) {
					appPathDiscoveryStackWalk = new FileIOPermission (
						FileIOPermissionAccess.PathDiscovery, "<apppath>");
				}
				return appPathDiscoveryStackWalk;
			}
		}

		internal static IStackWalk ControlPrincipal {
			get {
				if (ctrlPrincipalStackWalk == null) {
					ctrlPrincipalStackWalk = new SecurityPermission (
						SecurityPermissionFlag.ControlPrincipal);
				}
				return ctrlPrincipalStackWalk;
			}
		}

		internal static IStackWalk Reflection {
			get {
				if (reflectionStackWalk == null) {
					reflectionStackWalk = new ReflectionPermission (
						ReflectionPermissionFlag.TypeInformation |
						ReflectionPermissionFlag.MemberAccess);
				}
				return reflectionStackWalk;
			}
		}

		internal static IStackWalk SensitiveInformation {
			get {
				if (sensitiveInfoStackWalk == null) {
					sensitiveInfoStackWalk = new EnvironmentPermission (
						PermissionState.Unrestricted);
				}
				return sensitiveInfoStackWalk;
			}
		}

		internal static IStackWalk UnmanagedCode {
			get {
				if (unmgdCodeStackWalk == null) {
					unmgdCodeStackWalk = new SecurityPermission (
						SecurityPermissionFlag.UnmanagedCode);
				}
				return unmgdCodeStackWalk;
			}
		}

		internal static IStackWalk Unrestricted {
			get {
				if (unrestrictedStackWalk == null) {
					unrestrictedStackWalk = new PermissionSet (
						PermissionState.Unrestricted);
				}
				return unrestrictedStackWalk;
			}
		}

		internal static IStackWalk FileReadAccess (string file)
		{
			return new FileIOPermission (FileIOPermissionAccess.Read, file);
		}

		internal static IStackWalk PathDiscoveryAccess (string path)
		{
			return new FileIOPermission (FileIOPermissionAccess.PathDiscovery, path);
		}
	}
}