using System;
using System.Net;
using System.Text.RegularExpressions;
using JD.Interfaces.Remoting;

namespace JD.Remoting
{
    /// <summary>
    /// The full identifier of a remote host to connect to (IP + Port).
    /// </summary>
    public struct EndPointId : IEndPointId
    {
        /// <summary>
        /// Use this Ip to listen to any ip.
        /// </summary>
        public const string AnyIp = "any";

        /// <summary>
        /// Wheter the current instance was initialized using the explicit constructor.
        /// </summary>
        private readonly bool _initialized;
        private readonly string _ip;
        private readonly int _port;

        public EndPointId(string ip, int port)
        {
            Regex ipAddressRegex = new Regex(@"^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$");
            if (ipAddressRegex.Match(ip).Success)
            {
                _ip = ip;
            }
            else
            {
                throw new Exception($"The Ip Address :  {ip}, is NOT valid");
            }
            _port = port;
            _initialized = true;
        }

        public static IEndPointId Default
        {
            get { return new EndPointId("127.0.0.1", 1001); }
        }

        public int Port
        {
            get { return _initialized ? _port : Default.Port; }
        }

        public string IP
        {
            get { return _initialized ? _ip : Default.IP; }
        }

        public IPAddress IpAddress
        {
            get
            {
                if (IP == AnyIp)
                {
                    return IPAddress.Any;
                }
                else if (IP == Default.IP)
                {
                    return IPAddress.Loopback;
                }
                return IPAddress.Parse(IP);
            }
        }

        public IEndPointId GetNextPort()
        {
            return new EndPointId(_ip, _port + 1);
        }

        /// <inheritdoc />
        public override string ToString()
        {
            return $"{IP}:{Port}";
        }
    }
}