//
// System.AppDomain.cs
//
// Authors:
//   Paolo Molaro (lupus@ximian.com)
//   Dietmar Maurer (dietmar@ximian.com)
//   Miguel de Icaza (miguel@ximian.com)
//   Gonzalo Paniagua (gonzalo@ximian.com)
//   Patrik Torstensson
//   Sebastien Pouliot (sebastien@ximian.com)
//
// (C) 2001, 2002 Ximian, Inc.  http://www.ximian.com
// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System.Collections;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Reflection.Emit;
using System.Threading;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Contexts;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Messaging;
using System.Security;
using System.Security.Permissions;
using System.Security.Policy;
using System.Security.Principal;
using System.Configuration.Assemblies;

#if NET_2_0
using System.Runtime.ConstrainedExecution;
#endif

namespace System {

#if NET_2_0
	[ComVisible (true)]
#endif
	[ClassInterface(ClassInterfaceType.None)]
	public sealed class AppDomain : MarshalByRefObject , _AppDomain , IEvidenceFactory
	{
		IntPtr _mono_app_domain;
		static string _process_guid;

		[ThreadStatic]
		static Hashtable type_resolve_in_progress;

		[ThreadStatic]
		static Hashtable assembly_resolve_in_progress;

		// CAS
		private Evidence _evidence;
		private PermissionSet _granted;

		// non-CAS
		private PrincipalPolicy _principalPolicy;

		[ThreadStatic]
		private static IPrincipal _principal;

		private AppDomain ()
		{
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		private extern AppDomainSetup getSetup ();

		AppDomainSetup SetupInformationNoCopy {
			get { return getSetup (); }
		}

		public AppDomainSetup SetupInformation {
			get {
				AppDomainSetup setup = getSetup ();
				return new AppDomainSetup (setup);
			}
		}

		public string BaseDirectory {
			get {
				string path = SetupInformationNoCopy.ApplicationBase;
				if (SecurityManager.SecurityEnabled && (path != null) && (path.Length > 0)) {
					// we cannot divulge local file informations
					new FileIOPermission (FileIOPermissionAccess.PathDiscovery, path).Demand ();
				}
				return path;
			}
		}

		public string RelativeSearchPath {
			get {
				string path = SetupInformationNoCopy.PrivateBinPath;
				if (SecurityManager.SecurityEnabled && (path != null) && (path.Length > 0)) {
					// we cannot divulge local file informations
					new FileIOPermission (FileIOPermissionAccess.PathDiscovery, path).Demand ();
				}
				return path;
			}
		}

		public string DynamicDirectory {
			get {
				AppDomainSetup setup = SetupInformationNoCopy;
				if (setup.DynamicBase == null)
					return null;

				string path = Path.Combine (setup.DynamicBase, setup.ApplicationName);
				if (SecurityManager.SecurityEnabled && (path != null) && (path.Length > 0)) {
					// we cannot divulge local file informations
					new FileIOPermission (FileIOPermissionAccess.PathDiscovery, path).Demand ();
				}
				return path;
			}
		}

		public bool ShadowCopyFiles {
			get {
				return (SetupInformationNoCopy.ShadowCopyFiles == "true");
			}
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		private extern string getFriendlyName ();

		public string FriendlyName {
			get {
				return getFriendlyName ();
			}
		}

		public Evidence Evidence {
			get {
				// if the host (runtime) hasn't provided it's own evidence...
				if (_evidence == null) {
					// ... we will provide our own
					lock (this) {
						// the executed assembly from the "default" appdomain
						// or null if we're not in the default appdomain
						Assembly a = Assembly.GetEntryAssembly ();
						if (a == null)
							_evidence = AppDomain.DefaultDomain.Evidence;
						else
							_evidence = Evidence.GetDefaultHostEvidence (a);
					}
				}
				return new Evidence (_evidence);	// return a copy
			}
		}

		internal IPrincipal DefaultPrincipal {
			get {
				if (_principal == null) {
					switch (_principalPolicy) {
						case PrincipalPolicy.UnauthenticatedPrincipal:
							_principal = new GenericPrincipal (
								new GenericIdentity (String.Empty, String.Empty), null);
							break;
						case PrincipalPolicy.WindowsPrincipal:
							_principal = new WindowsPrincipal (WindowsIdentity.GetCurrent ());
							break;
					}
				}
				return _principal; 
			}
		}

		// for AppDomain there is only an allowed (i.e. granted) set
		// http://msdn.microsoft.com/library/en-us/cpguide/html/cpcondetermininggrantedpermissions.asp
		internal PermissionSet GrantedPermissionSet {
			get { return _granted; }
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		private static extern AppDomain getCurDomain ();
		
		public static AppDomain CurrentDomain {
			get {
				return getCurDomain ();
			}
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		private static extern AppDomain getRootDomain ();

		internal static AppDomain DefaultDomain {
			get {
				return getRootDomain ();
			}
		}

#if NET_2_0
		[Obsolete ("")]
#endif
		[SecurityPermission (SecurityAction.LinkDemand, ControlAppDomain = true)]
		public void AppendPrivatePath (string path)
		{
			if (path == null || path.Length == 0)
				return;

			AppDomainSetup setup = SetupInformationNoCopy;

			string pp = setup.PrivateBinPath;
			if (pp == null || pp.Length == 0) {
				setup.PrivateBinPath = path;
				return;
			}

			pp = pp.Trim ();
			if (pp [pp.Length - 1] != Path.PathSeparator)
				pp += Path.PathSeparator;

			setup.PrivateBinPath = pp + path;
		}

#if NET_2_0
		[Obsolete ("")]
#endif
		[SecurityPermission (SecurityAction.LinkDemand, ControlAppDomain = true)]
		public void ClearPrivatePath ()
		{
			SetupInformationNoCopy.PrivateBinPath = String.Empty;
		}

		[SecurityPermission (SecurityAction.LinkDemand, ControlAppDomain = true)]
		public void ClearShadowCopyPath ()
		{
			SetupInformationNoCopy.ShadowCopyDirectories = String.Empty;
		}

		public ObjectHandle CreateComInstanceFrom (string assemblyName, string typeName)
		{
			return Activator.CreateComInstanceFrom (assemblyName, typeName);
		}

#if NET_1_1
		public ObjectHandle CreateComInstanceFrom (string assemblyName, string typeName,
			byte [] hashValue, AssemblyHashAlgorithm hashAlgorithm)
		{
			return Activator.CreateComInstanceFrom (assemblyName, typeName, hashValue ,hashAlgorithm);
		}
#endif

		public ObjectHandle CreateInstance (string assemblyName, string typeName)
		{
			if (assemblyName == null)
				throw new ArgumentNullException ("assemblyName");

			return Activator.CreateInstance (assemblyName, typeName);
		}

		public ObjectHandle CreateInstance (string assemblyName, string typeName, object[] activationAttributes)
		{
			if (assemblyName == null)
				throw new ArgumentNullException ("assemblyName");

			return Activator.CreateInstance (assemblyName, typeName, activationAttributes);
		}

		public ObjectHandle CreateInstance (string assemblyName, string typeName, bool ignoreCase, BindingFlags bindingAttr,
		                                    Binder binder, object[] args, CultureInfo culture, object[] activationAttributes,
		                                    Evidence securityAttributes)
		{
			if (assemblyName == null)
				throw new ArgumentNullException ("assemblyName");

			return Activator.CreateInstance (assemblyName, typeName, ignoreCase, bindingAttr, binder, args,
				culture, activationAttributes, securityAttributes);
		}

		public object CreateInstanceAndUnwrap (string assemblyName, string typeName)
		{
			ObjectHandle oh = CreateInstance (assemblyName, typeName);
			return (oh != null) ? oh.Unwrap () : null;
		}

		public object CreateInstanceAndUnwrap (string assemblyName, string typeName, object [] activationAttributes)
		{
			ObjectHandle oh = CreateInstance (assemblyName, typeName, activationAttributes);
			return (oh != null) ? oh.Unwrap () : null;
		}

		public object CreateInstanceAndUnwrap (string assemblyName, string typeName, bool ignoreCase,
		                                       BindingFlags bindingAttr, Binder binder, object[] args, CultureInfo culture,
		                                       object[] activationAttributes, Evidence securityAttributes)
		{
			ObjectHandle oh = CreateInstance (assemblyName, typeName, ignoreCase, bindingAttr, binder, args,
				culture, activationAttributes, securityAttributes);
			return (oh != null) ? oh.Unwrap () : null;
		}

		public ObjectHandle CreateInstanceFrom (string assemblyName, string typeName)
		{
			if (assemblyName == null)
				throw new ArgumentNullException ("assemblyName");

			return Activator.CreateInstanceFrom (assemblyName, typeName);
		}

		public ObjectHandle CreateInstanceFrom (string assemblyName, string typeName, object[] activationAttributes)
		{
			if (assemblyName == null)
				throw new ArgumentNullException ("assemblyName");

			return Activator.CreateInstanceFrom (assemblyName, typeName, activationAttributes);
		}

		public ObjectHandle CreateInstanceFrom (string assemblyName, string typeName, bool ignoreCase,
		                                        BindingFlags bindingAttr, Binder binder, object[] args, CultureInfo culture,
		                                        object[] activationAttributes, Evidence securityAttributes)
		{
			if (assemblyName == null)
				throw new ArgumentNullException ("assemblyName");

			return Activator.CreateInstanceFrom (assemblyName, typeName, ignoreCase, bindingAttr, binder, args,
			                                     culture, activationAttributes, securityAttributes);
		}

		public object CreateInstanceFromAndUnwrap (string assemblyName, string typeName)
		{
			ObjectHandle oh = CreateInstanceFrom (assemblyName, typeName);
			return (oh != null) ? oh.Unwrap () : null;
		}

		public object CreateInstanceFromAndUnwrap (string assemblyName, string typeName, object [] activationAttributes)
		{
			ObjectHandle oh = CreateInstanceFrom (assemblyName, typeName, activationAttributes);
			return (oh != null) ? oh.Unwrap () : null;
		}

		public object CreateInstanceFromAndUnwrap (string assemblyName, string typeName, bool ignoreCase,
		                                           BindingFlags bindingAttr, Binder binder, object[] args,
		                                           CultureInfo culture, object[] activationAttributes,
		                                           Evidence securityAttributes)
		{
			ObjectHandle oh = CreateInstanceFrom (assemblyName, typeName, ignoreCase, bindingAttr, binder, args,
				culture, activationAttributes, securityAttributes);

			return (oh != null) ? oh.Unwrap () : null;
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access)
		{
			return DefineDynamicAssembly (name, access, null, null, null, null, null, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, Evidence evidence)
		{
			return DefineDynamicAssembly (name, access, null, evidence, null, null, null, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, string dir)
		{
			return DefineDynamicAssembly (name, access, dir, null, null, null, null, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, string dir,
		                                              Evidence evidence)
		{
			return DefineDynamicAssembly (name, access, dir, evidence, null, null, null, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access,
		                                              PermissionSet requiredPermissions,
		                                              PermissionSet optionalPermissions,
		                                              PermissionSet refusedPermissions)
		{
			return DefineDynamicAssembly (name, access, null, null, requiredPermissions, optionalPermissions,
				refusedPermissions, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, Evidence evidence,
		                                              PermissionSet requiredPermissions,
		                                              PermissionSet optionalPermissions,
		                                              PermissionSet refusedPermissions)
		{
			return DefineDynamicAssembly (name, access, null, evidence, requiredPermissions, optionalPermissions,
				refusedPermissions, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, string dir,
		                                              PermissionSet requiredPermissions,
		                                              PermissionSet optionalPermissions,
		                                              PermissionSet refusedPermissions)
		{
			return DefineDynamicAssembly (name, access, dir, null, requiredPermissions, optionalPermissions,
				refusedPermissions, false);
		}

		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, string dir,
		                                              Evidence evidence,
		                                              PermissionSet requiredPermissions,
		                                              PermissionSet optionalPermissions,
		                                              PermissionSet refusedPermissions)
		{
			return DefineDynamicAssembly (name, access, dir, evidence, requiredPermissions, optionalPermissions,
				refusedPermissions, false);
		}

		[MonoTODO ("FIXME: examine all other parameters")]
		public AssemblyBuilder DefineDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access, string dir,
		                                              Evidence evidence,
		                                              PermissionSet requiredPermissions,
		                                              PermissionSet optionalPermissions,
		                                              PermissionSet refusedPermissions, bool isSynchronized)
		{
			// FIXME: examine all other parameters
			
			AssemblyBuilder ab = new AssemblyBuilder (name, dir, access, false);
			ab.AddPermissionRequests (requiredPermissions, optionalPermissions, refusedPermissions);
			return ab;
		}

		internal AssemblyBuilder DefineInternalDynamicAssembly (AssemblyName name, AssemblyBuilderAccess access)
		{
			return new AssemblyBuilder (name, null, access, true);
		}

		public void DoCallBack (CrossAppDomainDelegate theDelegate)
		{
			if (theDelegate != null)
				theDelegate ();
		}

		public int ExecuteAssembly (string assemblyFile)
		{
			return ExecuteAssembly (assemblyFile, null, null);
		}

		public int ExecuteAssembly (string assemblyFile, Evidence assemblySecurity)
		{
			return ExecuteAssembly (assemblyFile, assemblySecurity, null);
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		public extern int ExecuteAssembly (string assemblyFile, Evidence assemblySecurity, string[] args);

		[MonoTODO]
		public int ExecuteAssembly (string assemblyFile, Evidence assemblySecurity, string[] args, byte[] hashValue, AssemblyHashAlgorithm hashAlgorithm)
		{
			throw new NotImplementedException ();
		}
		
		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		private extern Assembly [] GetAssemblies (bool refOnly);

		public Assembly [] GetAssemblies ()
		{
			return GetAssemblies (false);
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		public extern object GetData (string name);

		public new Type GetType()
		{
			return base.GetType ();
		}

		public override object InitializeLifetimeService ()
		{
			return null;
		}

		[MethodImplAttribute (MethodImplOptions.InternalCall)]
		internal extern Assembly LoadAssembly (string assemblyRef, Evidence securityEvidence, bool refOnly);

		public Assembly Load (AssemblyName assemblyRef)
		{
			return Load (assemblyRef, null);
		}

		public Assembly Load (AssemblyName assemblyRef, Evidence assemblySecurity)
		{
			if (assemblyRef == null)
				throw new ArgumentNullException ("assemblyRef");

			if (assemblyRef.Name == null || assemblyRef.Name.Length == 0) {
				if (assemblyRef.CodeBase != null)
					return Assembly.LoadFrom (assemblyRef.CodeBase, assemblySecurity);
				else
					throw new