using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace Sog.Crypto
{
    /// <summary>
    /// tea密钥生成器
    /// </summary>
    public class TeaKeyGenerator : Singleton<TeaKeyGenerator>
    {
        Random m_random;
        object m_locker = new object();

        public TeaKeyGenerator()
        {
            m_random = new Random((int)DateTime.Now.Ticks);
        }

        //先简单点，随机
        public byte[] GenerateNew()
        {
            //tea,xtea,xxtea的key是128bit，4个int，16byte
            byte[] key = new byte[16];

            //保证多线程安全
            lock (m_locker)
            {
                m_random.NextBytes(key);

                for (int i = 0; i < key.Length; i++)
                {
                    while (key[i] == 0)
                    {
                        key[i] = (byte)m_random.Next(256);
                    }
                }
            }

            return key;
        }

        public SogFastXTEAKey GenerateFastXTEAKey()
        {
            byte[] keyBytes = GenerateNew();

            return new SogFastXTEAKey(keyBytes);
        }
    }
}