using HslCommunication.BasicFramework;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace HslCommunication
{

    /*******************************************************************************
     * 
     *    一个通信辅助类，对通信中的数据做了信号区分
     *
     *    Communications helper classes, the data signal in a communications distinction
     * 
     *******************************************************************************/


    /// <summary>
    /// 用于本程序集访问通信的暗号说明
    /// </summary>
    public class HslProtocol
    {
        /// <summary>
        /// 规定所有的网络传输指令头都为32字节
        /// </summary>
        //internal const int HeadByteLength = 32;
        public static int HeadByteLength = 8;// cxy

        /// <summary>
        /// 所有网络通信中的缓冲池数据信息
        /// </summary>
        internal const int ProtocolBufferSize = 1024;


        /// <summary>
        /// 用于心跳程序的暗号信息
        /// </summary>
        internal const int ProtocolCheckSecends = 1;
        /// <summary>
        /// 客户端退出消息
        /// </summary>
        internal const int ProtocolClientQuit = 2;
        /// <summary>
        /// 因为客户端达到上限而拒绝登录
        /// </summary>
        internal const int ProtocolClientRefuseLogin = 3;
        /// <summary>
        /// 允许客户端登录到服务器
        /// </summary>
        internal const int ProtocolClientAllowLogin = 4;




        /// <summary>
        /// 说明发送的只是文本信息
        /// </summary>
        internal const int ProtocolUserString = 1001;
        /// <summary>
        /// 发送的数据就是普通的字节数组
        /// </summary>
        internal const int ProtocolUserBytes = 1002;
        /// <summary>
        /// 发送的数据就是普通的图片数据
        /// </summary>
        internal const int ProtocolUserBitmap = 1003;
        /// <summary>
        /// 发送的数据是一条异常的数据，字符串为异常消息
        /// </summary>
        internal const int ProtocolUserException = 1004;




        /// <summary>
        /// 请求文件下载的暗号
        /// </summary>
        internal const int ProtocolFileDownload = 2001;
        /// <summary>
        /// 请求文件上传的暗号
        /// </summary>
        internal const int ProtocolFileUpload = 2002;
        /// <summary>
        /// 请求删除文件的暗号
        /// </summary>
        internal const int ProtocolFileDelete = 2003;
        /// <summary>
        /// 文件校验成功
        /// </summary>
        internal const int ProtocolFileCheckRight = 2004;
        /// <summary>
        /// 文件校验失败
        /// </summary>
        internal const int ProtocolFileCheckError = 2005;
        /// <summary>
        /// 文件保存失败
        /// </summary>
        internal const int ProtocolFileSaveError = 2006;
        /// <summary>
        /// 请求文件列表的暗号
        /// </summary>
        internal const int ProtocolFileDirectoryFiles = 2007;
        /// <summary>
        /// 请求子文件的列表暗号
        /// </summary>
        internal const int ProtocolFileDirectories = 2008;
        /// <summary>
        /// 进度返回暗号
        /// </summary>
        internal const int ProtocolProgressReport = 2009;




        /// <summary>
        /// 不压缩数据字节
        /// </summary>
        internal const int ProtocolNoZipped = 3001;
        /// <summary>
        /// 压缩数据字节
        /// </summary>
        internal const int ProtocolZipped  = 3002;



        /// <summary>
        /// 生成终极传送指令的方法，所有的数据均通过该方法出来
        /// </summary>
        /// <param name="command">命令头</param>
        /// <param name="customer">自用自定义</param>
        /// <param name="token">令牌</param>
        /// <param name="data">字节数据</param>
        /// <returns></returns>
        internal static byte[] CommandBytes( int command, int customer, Guid token, byte[] data )
        {
            byte[] _temp = null;
            int _zipped = ProtocolNoZipped;
            int _sendLength = 0;
            if (data == null)
            {
                _temp = new byte[HeadByteLength];
            }
            else
            {
                // 加密
                data = HslSecurity.ByteEncrypt( data );
                if (data.Length > 102400)
                {
                    // 100K以上的数据，进行数据压缩
                    data = SoftZipped.CompressBytes( data );
                    _zipped = ProtocolZipped;
                }
                _temp = new byte[HeadByteLength + data.Length];
                _sendLength = data.Length;
            }
            BitConverter.GetBytes( command ).CopyTo( _temp, 0 );
            BitConverter.GetBytes( customer ).CopyTo( _temp, 4 );
            BitConverter.GetBytes( _zipped ).CopyTo( _temp, 8 );
            token.ToByteArray( ).CopyTo( _temp, 12 );
            BitConverter.GetBytes( _sendLength ).CopyTo( _temp, 28 );
            if (_sendLength > 0)
            {
                Array.Copy( data, 0, _temp, 32, _sendLength );
            }
            return _temp;
        }


        /// <summary>
        /// 解析接收到数据，先解压缩后进行解密
        /// </summary>
        /// <param name="head"></param>
        /// <param name="content"></param>
        internal static byte[] CommandAnalysis( byte[] head, byte[] content )
        {
            if (content != null)
            {
                int _zipped = BitConverter.ToInt32( head, 8 );
                // 先进行解压
                if (_zipped == ProtocolZipped)
                {
                    content = SoftZipped.Decompress( content );
                }
                // 进行解密
                return HslSecurity.ByteDecrypt( content );
            }
            else
            {
                return null;
            }
        }


        /// <summary>
        /// 获取发送字节数据的实际数据，带指令头
        /// </summary>
        /// <param name="customer"></param>
        /// <param name="token"></param>
        /// <param name="data"></param>
        /// <returns></returns>
        internal static byte[] CommandBytes( int customer, Guid token, byte[] data )
        {
            return CommandBytes( ProtocolUserBytes, customer, token, data );
        }


        /// <summary>
        /// 获取发送字节数据的实际数据，带指令头
        /// </summary>
        /// <param name="customer"></param>
        /// <param name="token"></param>
        /// <param name="data"></param>
        /// <returns></returns>
        internal static byte[] CommandBytes( int customer, Guid token, string data )
        {
            if (data == null) return CommandBytes( ProtocolUserString, customer, token, null );
            else return CommandBytes( ProtocolUserString, customer, token, Encoding.Unicode.GetBytes( data ) );
        }
    }


}