// Copyright (c) Microsoft Open Technologies, Inc.
// All Rights Reserved
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
// WITHOUT LIMITATION ANY IMPLIED WARRANTIES OR CONDITIONS OF
// TITLE, FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABLITY OR
// NON-INFRINGEMENT.
// See the Apache 2 License for the specific language governing
// permissions and limitations under the License.

// -----------------------------------------------------------------------
// <copyright file="ValidationHelper.cs" company="Microsoft">
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
// -----------------------------------------------------------------------

namespace Microsoft.AspNet.Security.Windows
{
    using System;
    using System.Diagnostics;
    using System.Diagnostics.CodeAnalysis;
    using System.Globalization;
    using System.Net.Security;
    using System.Runtime.InteropServices;
    using System.Runtime.Versioning;
    using System.Security.Authentication.ExtendedProtection;
    using System.Security.Cryptography.X509Certificates;
    using System.Security.Permissions;

    internal static class ValidationHelper
    {
        public static string ExceptionMessage(Exception exception)
        {
            if (exception == null)
            {
                return string.Empty;
            }
            if (exception.InnerException == null)
            {
                return exception.Message;
            }
            return exception.Message + " (" + ExceptionMessage(exception.InnerException) + ")";
        }

        public static string ToString(object objectValue)
        {
            if (objectValue == null)
            {
                return "(null)";
            }
            else if (objectValue is string && ((string)objectValue).Length == 0)
            {
                return "(string.empty)";
            }
            else if (objectValue is Exception)
            {
                return ExceptionMessage(objectValue as Exception);
            }
            else if (objectValue is IntPtr)
            {
                return "0x" + ((IntPtr)objectValue).ToString("x");
            }
            else
            {
                return objectValue.ToString();
            }
        }
        public static string HashString(object objectValue)
        {
            if (objectValue == null)
            {
                return "(null)";
            }
            else if (objectValue is string && ((string)objectValue).Length == 0)
            {
                return "(string.empty)";
            }
            else
            {
                return objectValue.GetHashCode().ToString(NumberFormatInfo.InvariantInfo);
            }
        }
    }
}