//-----------------------------------------------------------------------------
// Copyright (c) Microsoft Corporation.  All rights reserved.
//-----------------------------------------------------------------------------

namespace System.ServiceModel.Description
{
    using System.Collections;
    using System.Collections.Generic;
    using System.Collections.ObjectModel;
    using System.ComponentModel;
    using System.Diagnostics;
    using System.Runtime.Diagnostics;
    using System.ServiceModel.Channels;
    using System.ServiceModel.Diagnostics;
    using System.ServiceModel.Dispatcher;

    public class ServiceDebugBehavior : IServiceBehavior
    {
        bool includeExceptionDetailInFaults = false;

        bool httpHelpPageEnabled = true;
        Uri httpHelpPageUrl;

        bool httpsHelpPageEnabled = true;
        Uri httpsHelpPageUrl;

        Binding httpHelpPageBinding;
        Binding httpsHelpPageBinding;

        [DefaultValue(true)]
        public bool HttpHelpPageEnabled
        {
            get { return this.httpHelpPageEnabled; }
            set { this.httpHelpPageEnabled = value; }
        }

        [DefaultValue(null)]
        [TypeConverter(typeof(UriTypeConverter))]
        public Uri HttpHelpPageUrl
        {
            get { return this.httpHelpPageUrl; }
            set
            {
                if (value != null && value.IsAbsoluteUri && value.Scheme != Uri.UriSchemeHttp)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgument(SR.GetString(SR.SFxServiceMetadataBehaviorUrlMustBeHttpOrRelative,
                        "HttpHelpPageUrl", Uri.UriSchemeHttp, value.ToString(), value.Scheme));
                }
                this.httpHelpPageUrl = value;
            }
        }

        [DefaultValue(true)]
        public bool HttpsHelpPageEnabled
        {
            get { return this.httpsHelpPageEnabled; }
            set { this.httpsHelpPageEnabled = value; }
        }

        [DefaultValue(null)]
        [TypeConverter(typeof(UriTypeConverter))]
        public Uri HttpsHelpPageUrl
        {
            get { return this.httpsHelpPageUrl; }
            set
            {
                if (value != null && value.IsAbsoluteUri && value.Scheme != Uri.UriSchemeHttps)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgument(SR.GetString(SR.SFxServiceMetadataBehaviorUrlMustBeHttpOrRelative,
                        "HttpsHelpPageUrl", Uri.UriSchemeHttps, value.ToString(), value.Scheme));
                }
                this.httpsHelpPageUrl = value;
            }
        }

        public Binding HttpHelpPageBinding
        {
            get { return this.httpHelpPageBinding; }
            set
            {
                if (value != null)
                {
                    if (!value.Scheme.Equals(Uri.UriSchemeHttp, StringComparison.OrdinalIgnoreCase))
                    {
                        throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgument(SR.GetString(SR.SFxBindingSchemeDoesNotMatch,
                            value.Scheme, value.GetType().ToString(), Uri.UriSchemeHttp));
                    }
                    CustomBinding customBinding = new CustomBinding(value);
                    TextMessageEncodingBindingElement textMessageEncodingBindingElement = customBinding.Elements.Find<TextMessageEncodingBindingElement>();
                    if (textMessageEncodingBindingElement != null && !textMessageEncodingBindingElement.MessageVersion.IsMatch(MessageVersion.None))
                    {
                        throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgument(SR.GetString(SR.SFxIncorrectMessageVersion,
                            textMessageEncodingBindingElement.MessageVersion.ToString(), MessageVersion.None.ToString()));
                    }
                    HttpTransportBindingElement httpTransportBindingElement = customBinding.Elements.Find<HttpTransportBindingElement>();
                    if (httpTransportBindingElement != null)
                    {
                        httpTransportBindingElement.Method = "GET";
                    }
                    this.httpHelpPageBinding = customBinding;
                }
            }
        }

        public Binding HttpsHelpPageBinding
        {
            get { return this.httpsHelpPageBinding; }
            set
            {
                if (value != null)
                {
                    if (!value.Scheme.Equals(Uri.UriSchemeHttps, StringComparison.OrdinalIgnoreCase))
                    {
                        throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgument(SR.GetString(SR.SFxBindingSchemeDoesNotMatch,
                            value.Scheme, value.GetType().ToString(), Uri.UriSchemeHttps));
                    }
                    CustomBinding customBinding = new CustomBinding(value);
                    TextMessageEncodingBindingElement textMessageEncodingBindingElement = customBinding.Elements.Find<TextMessageEncodingBindingElement>();
                    if (textMessageEncodingBindingElement != null && !textMessageEncodingBindingElement.MessageVersion.IsMatch(MessageVersion.None))
                    {
                        throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgument(SR.GetString(SR.SFxIncorrectMessageVersion,
                            textMessageEncodingBindingElement.MessageVersion.ToString(), MessageVersion.None.ToString()));
                    }
                    HttpsTransportBindingElement httpsTransportBindingElement = customBinding.Elements.Find<HttpsTransportBindingElement>();
                    if (httpsTransportBindingElement != null)
                    {
                        httpsTransportBindingElement.Method = "GET";
                    }
                    this.httpsHelpPageBinding = customBinding;
                }
            }
        }

        [DefaultValue(false)]
        public bool IncludeExceptionDetailInFaults
        {
            get { return this.includeExceptionDetailInFaults; }
            set { this.includeExceptionDetailInFaults = value; }
        }

        void IServiceBehavior.Validate(ServiceDescription description, ServiceHostBase serviceHostBase)
        {
        }

        void IServiceBehavior.AddBindingParameters(ServiceDescription description, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection parameters)
        {
            if (parameters == null)
            {
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgumentNull("parameters");
            }

            ServiceDebugBehavior param = parameters.Find<ServiceDebugBehavior>();
            if (param == null)
            {
                parameters.Add(this);
            }
        }

        void IServiceBehavior.ApplyDispatchBehavior(ServiceDescription description, ServiceHostBase serviceHostBase)
        {
            if (this.includeExceptionDetailInFaults)
            {
                for (int i = 0; i < serviceHostBase.ChannelDispatchers.Count; i++)
                {
                    ChannelDispatcher channelDispatcher = serviceHostBase.ChannelDispatchers[i] as ChannelDispatcher;
                    if (channelDispatcher != null)
                    {
                        channelDispatcher.IncludeExceptionDetailInFaults = true;
                    }
                }
            }

            if (!(this.httpHelpPageEnabled || this.httpsHelpPageEnabled))
                return;

            ServiceMetadataExtension mex = ServiceMetadataExtension.EnsureServiceMetadataExtension(description, serviceHostBase);
            SetExtensionProperties(mex, serviceHostBase);
            CreateHelpPageEndpoints(description, serviceHostBase, mex);
        }

        private void SetExtensionProperties(ServiceMetadataExtension mex, ServiceHostBase host)
        {
            mex.HttpHelpPageEnabled = this.httpHelpPageEnabled;
            mex.HttpHelpPageUrl = host.GetVia(Uri.UriSchemeHttp, this.httpHelpPageUrl == null ? new Uri(string.Empty, UriKind.Relative) : this.httpHelpPageUrl);
            mex.HttpHelpPageBinding = this.HttpHelpPageBinding;

            mex.HttpsHelpPageEnabled = this.httpsHelpPageEnabled;
            mex.HttpsHelpPageUrl = host.GetVia(Uri.UriSchemeHttps, this.httpsHelpPageUrl == null ? new Uri(string.Empty, UriKind.Relative) : this.httpsHelpPageUrl);
            mex.HttpsHelpPageBinding = this.HttpsHelpPageBinding;
        }

        bool EnsureHelpPageDispatcher(ServiceHostBase host, ServiceMetadataExtension mex, Uri url, string scheme)
        {
            Uri address = host.GetVia(scheme, url == null ? new Uri(string.Empty, UriKind.Relative) : url);

            if (address == null)
            {
                return false;
            }

            ChannelDispatcher channelDispatcher = mex.EnsureGetDispatcher(address, true /* isServiceDebugBehavior */);
            ((ServiceMetadataExtension.HttpGetImpl)channelDispatcher.Endpoints[0].DispatchRuntime.SingletonInstanceContext.UserObject).HelpPageEnabled = true;

            return true;
        }

        void CreateHelpPageEndpoints(ServiceDescription description, ServiceHostBase host, ServiceMetadataExtension mex)
        {
            if (this.httpHelpPageEnabled)
            {
                if (!EnsureHelpPageDispatcher(host, mex, this.httpHelpPageUrl, Uri.UriSchemeHttp))
                {
                    TraceWarning(this.httpHelpPageUrl, "ServiceDebugBehaviorHttpHelpPageUrl", "ServiceDebugBehaviorHttpHelpPageEnabled");
                }
            }

            if (this.httpsHelpPageEnabled)
            {
                if (!EnsureHelpPageDispatcher(host, mex, this.httpsHelpPageUrl, Uri.UriSchemeHttps))
                {
                    TraceWarning(this.httpHelpPageUrl, "ServiceDebugBehaviorHttpsHelpPageUrl", "ServiceDebugBehaviorHttpsHelpPageEnabled");
                }
            }
        }

        static void TraceWarning(Uri address, string urlProperty, string enabledProperty)
        {
            if (DiagnosticUtility.ShouldTraceInformation)
            {
                Hashtable h = new Hashtable(2)
                {
                    { enabledProperty, "true" },
                    { urlProperty, (address == null) ? string.Empty : address.ToString() }
                };
                TraceUtility.TraceEvent(TraceEventType.Information, TraceCode.WarnHelpPageEnabledNoBaseAddress,
                    SR.GetString(SR.TraceCodeWarnHelpPageEnabledNoBaseAddress), new DictionaryTraceRecord(h), null, null);
            }
        }
    }
}