using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Net.NetworkInformation;

namespace Miracom.MESCore.Utils
{
    /// <summary>
    /// 封裝IP相關方法
    /// 包含方法：
    /// + static List getIPAddressList()
    /// + static string getIPAddress()
    /// + static string getIPAddressBySocket()
    /// + static string getIPAddressByNetworkInterface(NetworkInterfaceType _type)
    /// 
    /// </summary>
    /// <Author>CY</Author>
    public static class IPHelper
    {
        /// <summary>
        /// 獲取本機所有的IP地址
        /// </summary>
        /// <returns>IP字符串列表</returns>
        public static List<string> getIPAddressList()
        {
            List<string> ipList = new List<string>();
            IPHostEntry ipEntry = Dns.GetHostEntry(Dns.GetHostName());
            foreach (var ip in ipEntry.AddressList)
            {
                ipList.Add("IP Address: " + ip.ToString());
            }
            return ipList;
        }
        /// <summary>
        /// 獲取本機IPv4地址
        /// </summary>
        /// <returns>IPv4字符串</returns>
        public static string getIPAddress()
        {
            IPHostEntry host = Dns.GetHostEntry(Dns.GetHostName());
            foreach (IPAddress ip in host.AddressList)
            {
                if (ip.AddressFamily == AddressFamily.InterNetwork)//如果需要獲取ipv6地址，使用AddressFamily.InterNetworkV6
                {
                    return ip.ToString();
                }
            }
            return null;
        }
        /// <summary>
        /// 通過使用UDP Socket連接來查看本機IP地址
        /// 因為是獲取網絡連接中實際使用的IP，所以更準確
        /// </summary>
        /// <returns>IPv4字符串</returns>
        public static string getIPAddressBySocket()
        {
            string localIP = string.Empty;
            using (Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, 0))
            {
                socket.Connect("8.8.8.8", 65530);
                IPEndPoint endPoint = socket.LocalEndPoint as IPEndPoint;
                localIP = endPoint.Address.ToString();
            }
            return localIP;
        }
        /// <summary>
        /// 使用NetworkInterface查看 并返回指定類型的IP地址
        /// </summary>
        /// <param name="_type">可選參數：IP的具體類型，默認為Ethernet類型</param>
        /// <returns>指定的IP字符串</returns>
        public static string getIPAddressByNetworkInterface(NetworkInterfaceType _type = NetworkInterfaceType.Ethernet)
        {
            foreach (NetworkInterface item in NetworkInterface.GetAllNetworkInterfaces())
            {
                if (item.NetworkInterfaceType == _type && item.OperationalStatus == OperationalStatus.Up)
                {
                    foreach (UnicastIPAddressInformation ip in item.GetIPProperties().UnicastAddresses)
                    {
                        if (ip.Address.AddressFamily == AddressFamily.InterNetwork)
                        {
                            return ip.Address.ToString();
                        }
                    }
                }
            }
            return null;
        }

    }
}