using System;
using System.Collections.Generic;
using System.IdentityModel.Tokens;
using System.Threading;

namespace MyCompany.MyProject.ServiceModel.Description
{
    /// <summary> 
    /// Helper class used as cache for security tokens 
    /// </summary> 
    internal static class TokenCacheHelper
    {
        private const int DefaultTimeout = 1000;
        private static readonly Dictionary<Uri, SecurityToken> tokens = new Dictionary<Uri, SecurityToken>();
        private static readonly ReaderWriterLock tokenLock = new ReaderWriterLock();

        public static SecurityToken GetToken(Uri key)
        {           
            tokenLock.AcquireReaderLock(DefaultTimeout);

            try
            {
                SecurityToken token;

                tokens.TryGetValue(key, out token);

                return token;
            }
            finally
            {
                tokenLock.ReleaseReaderLock();
            }
        }

        public static void AddToken(Uri key, SecurityToken token)
        {
            tokenLock.AcquireWriterLock(DefaultTimeout);

            try
            {
                if (tokens.ContainsKey(key))
                    tokens.Remove(key);

                tokens.Add(key, token);
            }
            finally
            {
                tokenLock.ReleaseWriterLock();
            }
        }
    }
}