//
// ClientRuntimeChannel.cs
//
// Author:
//	Atsushi Enomoto <atsushi@ximian.com>
//
// Copyright (C) 2006 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;
using System.Collections.Generic;
using System.Reflection;
using System.Runtime.Serialization;
using System.ServiceModel.Channels;
using System.ServiceModel.Description;
using System.ServiceModel.Dispatcher;
using System.ServiceModel.Security;
using System.Threading;
using System.Xml;

namespace System.ServiceModel.MonoInternal
{
#if DISABLE_REAL_PROXY
	// FIXME: This is a quick workaround for bug #571907
	public
#endif
	interface IInternalContextChannel
	{
		ContractDescription Contract { get; }

		OperationContext Context { set; }

		object Process (MethodBase method, string operationName, object [] parameters);

		IAsyncResult BeginProcess (MethodBase method, string operationName, object [] parameters, AsyncCallback callback, object asyncState);

		object EndProcess (MethodBase method, string operationName, object [] parameters, IAsyncResult result);
	}

#if DISABLE_REAL_PROXY
	// FIXME: This is a quick workaround for bug #571907
	public
#endif
	class ClientRuntimeChannel
		: CommunicationObject, IClientChannel, IInternalContextChannel
	{
		ClientRuntime runtime;
		EndpointAddress remote_address;
		ContractDescription contract;
		MessageVersion message_version;
		TimeSpan default_open_timeout, default_close_timeout;
		IChannel channel;
		IChannelFactory factory;
		OperationContext context;

		#region delegates
		readonly ProcessDelegate _processDelegate;

		delegate object ProcessDelegate (MethodBase method, string operationName, object [] parameters);

		readonly RequestDelegate requestDelegate;

		delegate Message RequestDelegate (Message msg, TimeSpan timeout);

		readonly SendDelegate sendDelegate;

		delegate void SendDelegate (Message msg, TimeSpan timeout);
		#endregion

		public ClientRuntimeChannel (ServiceEndpoint endpoint,
			ChannelFactory channelFactory, EndpointAddress remoteAddress, Uri via)
			: this (endpoint.CreateClientRuntime (null), endpoint.Contract, channelFactory.DefaultOpenTimeout, channelFactory.DefaultCloseTimeout, null, channelFactory.OpenedChannelFactory, endpoint.Binding.MessageVersion, remoteAddress, via)
		{
		}

		public ClientRuntimeChannel (ClientRuntime runtime, ContractDescription contract, TimeSpan openTimeout, TimeSpan closeTimeout, IChannel contextChannel, IChannelFactory factory, MessageVersion messageVersion, EndpointAddress remoteAddress, Uri via)
		{
			if (runtime == null)
				throw new ArgumentNullException ("runtime");
			if (messageVersion == null)
				throw new ArgumentNullException ("messageVersion");
			this.runtime = runtime;
			this.remote_address = remoteAddress;
			if (runtime.Via == null)
				runtime.Via = via ?? (remote_address != null ?remote_address.Uri : null);
			this.contract = contract;
			this.message_version = messageVersion;
			default_open_timeout = openTimeout;
			default_close_timeout = closeTimeout;
			_processDelegate = new ProcessDelegate (Process);
			requestDelegate = new RequestDelegate (Request);
			sendDelegate = new SendDelegate (Send);

			// default values
			AllowInitializationUI = true;
			OperationTimeout = TimeSpan.FromMinutes (1);

			if (contextChannel != null)
				channel = contextChannel;
			else {
				var method = factory.GetType ().GetMethod ("CreateChannel", new Type [] {typeof (EndpointAddress), typeof (Uri)});
				try {
					channel = (IChannel) method.Invoke (factory, new object [] {remote_address, Via});
					this.factory = factory;
				} catch (TargetInvocationException ex) {
					if (ex.InnerException != null)
						throw ex.InnerException;
					else
						throw;
				}
			}
		}

		public ContractDescription Contract {
			get { return contract; }
		}

		public ClientRuntime Runtime {
			get { return runtime; }
		}

		IRequestChannel RequestChannel {
			get { return channel as IRequestChannel; }
		}

		IOutputChannel OutputChannel {
			get { return channel as IOutputChannel; }
		}

		internal IDuplexChannel DuplexChannel {
			get { return channel as IDuplexChannel; }
		}

		public OperationContext Context {
			set { context = value; }
		}

		#region IClientChannel

		bool did_interactive_initialization;

		public bool AllowInitializationUI { get; set; }

		public bool DidInteractiveInitialization {
			get { return did_interactive_initialization; }
		}

		public Uri Via {
			get { return runtime.Via; }
		}

		class DelegatingWaitHandle : WaitHandle
		{
			public DelegatingWaitHandle (IAsyncResult [] results)
			{
				this.results = results;
			}

			IAsyncResult [] results;

			protected override void Dispose (bool disposing)
			{
				if (disposing)
					foreach (var r in results)
						r.AsyncWaitHandle.Close ();
			}

			public override bool WaitOne ()
			{
				foreach (var r in results)
					r.AsyncWaitHandle.WaitOne ();
				return true;
			}

			public override bool WaitOne (int millisecondsTimeout)
			{
				return WaitHandle.WaitAll (ResultWaitHandles, millisecondsTimeout);
			}

			WaitHandle [] ResultWaitHandles {
				get {
					var arr = new WaitHandle [results.Length];
					for (int i = 0; i < arr.Length; i++)
						arr [i] = results [i].AsyncWaitHandle;
					return arr;
				}
			}

#if !MOONLIGHT
			public override bool WaitOne (int millisecondsTimeout, bool exitContext)
			{
				return WaitHandle.WaitAll (ResultWaitHandles, millisecondsTimeout, exitContext);
			}

			public override bool WaitOne (TimeSpan timeout, bool exitContext)
			{
				return WaitHandle.WaitAll (ResultWaitHandles, timeout, exitContext);
			}
#endif
		}

		class DisplayUIAsyncResult : IAsyncResult
		{
			public DisplayUIAsyncResult (IAsyncResult [] results)
			{
				this.results = results;
			}

			IAsyncResult [] results;

			internal IAsyncResult [] Results {
				get { return results; }
			}

			public object AsyncState {
				get { return null; }
			}

			WaitHandle wait_handle;

			public WaitHandle AsyncWaitHandle {
				get {
					if (wait_handle == null)
						wait_handle = new DelegatingWaitHandle (results);
					return wait_handle;
				}
			}

			public bool CompletedSynchronously {
				get {
					foreach (var r in results)
						if (!r.CompletedSynchronously)
							return false;
					return true;
				}
			}
			public bool IsCompleted {
				get {
					foreach (var r in results)
						if (!r.IsCompleted)
							return false;
					return true;
				}
			}
		}

		public IAsyncResult BeginDisplayInitializationUI (
			AsyncCallback callback, object state)
		{
			OnInitializationUI ();
			IAsyncResult [] arr = new IAsyncResult [runtime.InteractiveChannelInitializers.Count];
			int i = 0;
			foreach (var init in runtime.InteractiveChannelInitializers)
				arr [i++] = init.BeginDisplayInitializationUI (this, callback, state);
			return new DisplayUIAsyncResult (arr);
		}

		public void EndDisplayInitializationUI (
			IAsyncResult result)
		{
			DisplayUIAsyncResult r = (DisplayUIAsyncResult) result;
			int i = 0;
			foreach (var init in runtime.InteractiveChannelInitializers)
				init.EndDisplayInitializationUI (r.Results [i++]);

			did_interactive_initialization = true;
		}

		public void DisplayInitializationUI ()
		{
			OnInitializationUI ();
			foreach (var init in runtime.InteractiveChannelInitializers)
				init.EndDisplayInitializationUI (init.BeginDisplayInitializationUI (this, null, null));

			did_interactive_initialization = true;
		}

		void OnInitializationUI ()
		{
			if (!AllowInitializationUI && runtime.InteractiveChannelInitializers.Count > 0)
				throw new InvalidOperationException ("AllowInitializationUI is set to false but the client runtime contains one or more InteractiveChannelInitializers.");
		}

		public void Dispose ()
		{
			Close ();
		}

		public event EventHandler<UnknownMessageReceivedEventArgs> UnknownMessageReceived;

		#endregion

		#region IContextChannel

		[MonoTODO]
		public bool AllowOutputBatching { get; set; }

		public IInputSession InputSession {
			get {
				ISessionChannel<IInputSession> ch = RequestChannel as ISessionChannel<IInputSession>;
				ch = ch ?? OutputChannel as ISessionChannel<IInputSession>;
				if (ch != null)
					return ch.Session;
				var dch = OutputChannel as ISessionChannel<IDuplexSession>;
				return dch != null ? dch.Session : null;
			}
		}

		public EndpointAddress LocalAddress {
			get {
				var dc = OperationChannel as IDuplexChannel;
				return dc != null ? dc.LocalAddress : null;
			}
		}

		[MonoTODO]
		public TimeSpan OperationTimeout { get; set; }

		public IOutputSession OutputSession {
			get {
				ISessionChannel<IOutputSession> ch = RequestChannel as ISessionChannel<IOutputSession>;
				ch = ch ?? OutputChannel as ISessionChannel<IOutputSession>;
				if (ch != null)
					return ch.Session;
				var dch = OutputChannel as ISessionChannel<IDuplexSession>;
				return dch != null ? dch.Session : null;
			}
		}

		public EndpointAddress RemoteAddress {
			get { return RequestChannel != null ? RequestChannel.RemoteAddress : OutputChannel.RemoteAddress; }
		}

		public string SessionId {
			get { return OutputSession != null ? OutputSession.Id : InputSession != null ? InputSession.Id : null; }
		}

		#endregion

		// CommunicationObject
		protected internal override TimeSpan DefaultOpenTimeout {
			get { return default_open_timeout; }
		}

		protected internal override TimeSpan DefaultCloseTimeout {
			get { return default_close_timeout; }
		}

		protected override void OnAbort ()
		{
			channel.Abort ();
			if (factory != null) // ... is it valid?
				factory.Abort ();
		}

		Action<TimeSpan> close_delegate;

		protected override IAsyncResult OnBeginClose (
			TimeSpan timeout, AsyncCallback callback, object state)
		{
			if (close_delegate == null)
				close_delegate = new Action<TimeSpan> (OnClose);
			return close_delegate.BeginInvoke (timeout, callback, state);
		}

		protected override void OnEndClose (IAsyncResult result)
		{
			close_delegate.EndInvoke (result);
		}

		protected override void OnClose (TimeSpan timeout)
		{
			DateTime start = DateTime.Now;
			if (channel.State == CommunicationState.Opened)
				channel.Close (timeout);
		}

		Action<TimeSpan> open_callback;

		protected override IAsyncResult OnBeginOpen (
			TimeSpan timeout, AsyncCallback callback, object state)
		{
			if (open_callback == null)
				open_callback = new Action<TimeSpan> (OnOpen);
			return open_callback.BeginInvoke (timeout, callback, state);
		}

		protected override void OnEndOpen (IAsyncResult result)
		{
			if (open_callback == null)
				throw new InvalidOperationException ("Async open operation has not started");
			open_callback.EndInvoke (result);
		}

		protected override void OnOpen (TimeSpan timeout)
		{
			if (runtime.InteractiveChannelInitializers.Count > 0 && !DidInteractiveInitialization)
				throw new InvalidOperationException ("The client runtime is assigned interactive channel initializers, and in such case DisplayInitializationUI must be called before the channel is opened.");
			if (channel.State == CommunicationState.Created)
				channel.Open (timeout);
		}

		// IChannel

		IChannel OperationChannel {
			get { return channel; }
		}

		public T GetProperty<T> () where T : class
		{
			if (typeof (T) == typeof (MessageVersion))
				return (T) (object) message_version;
			return OperationChannel.GetProperty<T> ();
		}

		// IExtensibleObject<IContextChannel>

		IExtensionCollection<IContextChannel> extensions;

		public IExtensionCollection<IContextChannel> Extensions {
			get {
				if (extensions == null)
					extensions = new ExtensionCollection<IContextChannel> (this);
				return extensions;
			}
		}

		#region Request/Output processing

		public IAsyncResult BeginProcess (MethodBase method, string operationName, object [] parameters, AsyncCallback callback, object asyncState)
		{
			if (context != null)
				throw new InvalidOperationException ("another operation is in progress");
			context = OperationContext.Current;

			return _processDelegate.BeginInvoke (method, operationName, parameters, callback, asyncState);
		}

		public object EndProcess (MethodBase method, string operationName, object [] parameters, IAsyncResult result)
		{
				
			if (result == null)
				throw new ArgumentNullException ("result");
			if (parameters == null)
				throw new ArgumentNullException ("parameters");
			// FIXME: the method arguments should be verified to be 
			// identical to the arguments in the corresponding begin method.
			object asyncResult = _processDelegate.EndInvoke (result);
			context = null;
			return asyncResult;
		}

		public object Process (MethodBase method, string operationName, object [] parameters)
		{
			var previousContext = OperationContext.Current;
			try {
				// Inherit the context from the calling thread
				if (this.context != null) 
					OperationContext.Current = this.context;

				return DoProcess (method, operationName, parameters);
			} catch (Exception ex) {
#if MOONLIGHT // just for debugging
				Console.Write ("Exception in async operation: ");
				Console.WriteLine (ex);
#endif
				throw;
			} finally {
				// Reset the context before the thread goes back into the pool
				OperationContext.Current = previousContext;
			}
		}

		object DoProcess (MethodBase method, string operationName, object [] parameters)
		{
			if (AllowInitializationUI)
				DisplayInitializationUI ();
			OperationDescription od = SelectOperation (method, operationName, parameters);

			if (State != CommunicationState.Opened)
				Open ();

			if (!od.IsOneWay)
				return Request (od, parameters);
			else {
				Output (od, parameters);
				return null;
			}
		}

		OperationDescription SelectOperation (MethodBase method, string operationName, object [] parameters)
		{
			string operation;
			if (Runtime.OperationSelector != null)
				operation = Runtime.OperationSelector.SelectOperation (method, parameters);
			else
				operation = operationName;
			OperationDescription od = contract.Operations.Find (operation);
			if (od == null)
				throw new Exception (String.Format ("OperationDescription for operation '{0}' was not found in its internally-generated contract.", operation));
			return od;
		}

		void Output (OperationDescription od, object [] parameters)
		{
			ClientOperation op = runtime.Operations [od.Name];
			Send (CreateRequest (op, parameters), OperationTimeout);
		}

		object Request (OperationDescription od, object [] parameters)
		{
			ClientOperation op = runtime.Operations [od.Name];
			object [] inspections = new object [runtime.MessageInspectors.Count];
			Message req = CreateRequest (op, parameters);

			for (int i = 0; i < inspections.Length; i++)
				inspections [i] = runtime.MessageInspectors [i].BeforeSendRequest (ref req, this);

			Message res = Request (req, OperationTimeout);
			if (res.IsFault) {
				var resb = res.CreateBufferedCopy (runtime.MaxFaultSize);
				MessageFault fault = MessageFault.CreateFault (resb.CreateMessage (), runtime.MaxFaultSize);
				var conv = OperationChannel.GetProperty<FaultConverter> () ?? FaultConverter.GetDefaultFaultConverter (res.Version);
				Exception ex;
				if (!conv.TryCreateException (resb.CreateMessage (), fault, out ex)) {
					if (fault.HasDetail) {
						Type detailType = typeof (ExceptionDetail);
						var freader = fault.GetReaderAtDetailContents ();
						DataContractSerializer ds = null;
#if !NET_2_1
						foreach (var fci in op.FaultContractInfos)
							if (res.Headers.Action == fci.Action || fci.Serializer.IsStartObject (freader)) {
								detailType = fci.Detail;
								ds = fci.Serializer;
								break;
							}
#endif
						if (ds == null)
							ds = new DataContractSerializer (detailType);
						var detail = ds.ReadObject (freader);
						ex = (Exception) Activator.CreateInstance (typeof (FaultException<>).MakeGenericType (detailType), new object [] {detail, fault.Reason, fault.Code, res.Headers.Action});
					}

					if (ex == null)
						ex = new FaultException (fault);
				}
				throw ex;
			}

			for (int i = 0; i < inspections.Length; i++)
				runtime.MessageInspectors [i].AfterReceiveReply (ref res, inspections [i]);

			if (op.DeserializeReply)
				return op.Formatter.DeserializeReply (res, parameters);
			else
				return res;
		}

		#region Message-based Request() and Send()
		// They are internal for ClientBase<T>.ChannelBase use.
		internal Message Request (Message msg, TimeSpan timeout)
		{
			if (RequestChannel != null)
				return RequestChannel.Request (msg, timeout);
			else
				return RequestCorrelated (msg, timeout, OutputChannel);
		}

		internal virtual Message RequestCorrelated (Message msg, TimeSpan timeout, IOutputChannel channel)
		{
			// FIXME: implement ConcurrencyMode check:
			// if it is .Single && this instance for a callback channel && the operation is invoked inside service operation, then error.

			DateTime startTime = DateTime.Now;
			OutputChannel.Send (msg, timeout);
			return ((IDuplexChannel) channel).Receive (timeout - (DateTime.Now - startTime));
		}

		internal IAsyncResult BeginRequest (Message msg, TimeSpan timeout, AsyncCallback callback, object state)
		{
			return requestDelegate.BeginInvoke (msg, timeout, callback, state);
		}

		internal Message EndRequest (IAsyncResult result)
		{
			return requestDelegate.EndInvoke (result);
		}

		internal void Send (Message msg, TimeSpan timeout)
		{
			if (OutputChannel != null)
				OutputChannel.Send (msg, timeout);
			else
				RequestChannel.Request (msg, timeout); // and ignore returned message.
		}

		internal IAsyncResult BeginSend (Message msg, TimeSpan timeout, AsyncCallback callback, object state)
		{
			return sendDelegate.BeginInvoke (msg, timeout, callback, state);
		}

		internal void EndSend (IAsyncResult result)
		{
			sendDelegate.EndInvoke (result);
		}
		#endregion

		Message CreateRequest (ClientOperation op, object [] parameters)
		{
			MessageVersion version = message_version;
			if (version == null)
				version = MessageVersion.Default;

			Message msg;
			if (op.SerializeRequest)
				msg = op.Formatter.SerializeRequest (
					version, parameters);
			else {
				if (parameters.Length != 1)
					throw new ArgumentException (String.Format ("Argument parameters does not match the expected input. It should contain only a Message, but has {0} parameters", parameters.Length));
				if (!(parameters [0] is Message))
					throw new ArgumentException (String.Format ("Argument should be only a Message, but has {0}", parameters [0] != null ? parameters [0].GetType ().FullName : "null"));
				msg = (Message) parameters [0];
			}

			context = context ?? OperationContext.Current;
			if (context != null) {
				// CopyHeadersFrom does not work here (brings duplicates -> error)
				foreach (var mh in context.OutgoingMessageHeaders) {
					int x = msg.Headers.FindHeader (mh.Name, mh.Namespace, mh.Actor);
					if (x >= 0)
						msg.Headers.RemoveAt (x);
					msg.Headers.Add ((MessageHeader) mh);
				}
				msg.Properties.CopyProperties (context.OutgoingMessageProperties);
			}

			// FIXME: disabling MessageId as it's not seen for bug #567672 case. But might be required for PeerDuplexChannel. Check it later.
			//if (OutputSession != null)
			//	msg.Headers.MessageId = new UniqueId (OutputSession.Id);
			msg.Properties.AllowOutputBatching = AllowOutputBatching;

			if (msg.Version.Addressing.Equals (AddressingVersion.WSAddressing10)) {
				if (msg.Headers.MessageId == null)
					msg.Headers.MessageId = new UniqueId ();
				if (msg.Headers.ReplyTo == null)
					msg.Headers.ReplyTo = new EndpointAddress (Constants.WsaAnonymousUri);
				if (msg.Headers.To == null && RemoteAddress != null)
					msg.Headers.To = RemoteAddress.Uri;
			}

			return msg;
		}

		#endregion
	}
}