using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Sockets;
using System.IO;
using sharpknife.Utils;

namespace sharpknife.Data
{
    public class PopClient
    {
        public string Host { get; set; }
        public int Port { get; set; }
        public string Username { get; set; }
        public string Password { get; set; }

        private List<string> Status = new List<string>();
        public int Messages = 0;

        public PopClient(string host, int port, string username, string password)
        {
            this.Host = host;
            this.Port = port;
            this.Username = username;
            this.Password = password;
        }

        public void Connect()
        {
            Server = new TcpClient(Host, Port);
            Status.Clear();

            try
            {
                // initialization
                NetStrm = Server.GetStream();
                RdStrm = new StreamReader(Server.GetStream());
                Status.Add(RdStrm.ReadLine());

                // Login Process
                Data = "USER " + Username + CRLF;
                szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
                NetStrm.Write(szData, 0, szData.Length);
                Status.Add(RdStrm.ReadLine());

                Data = "PASS " + Password + CRLF;
                szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
                NetStrm.Write(szData, 0, szData.Length);
                Status.Add(RdStrm.ReadLine());

                // Send STAT command to get information ie: number of mail and size
                Data = "STAT" + CRLF;
                szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
                NetStrm.Write(szData, 0, szData.Length);

                string response = RdStrm.ReadLine();
                Status.Add(response);

                if (StringUtils.Contains(response, "+OK"))
                {
                    //string messages = StringUtils.GetToken(response, "+OK {} 2392");
                    //string[] messages = StringUtils.GetTokens(response, "+OK {} {}");
                    Messages = int.Parse(StringUtils.GetTokens(response, "+OK {} {}")[0]);
                }
            }
            catch (InvalidOperationException err)
            {
                Status.Add("Error: " + err.ToString());
            }
        }


        public void Disconnect()
        {
            // Send QUIT command to close session from POP server
            Data = "QUIT" + CRLF;
            szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
            NetStrm.Write(szData, 0, szData.Length);
            Status.Add(RdStrm.ReadLine());

            //close connection
            NetStrm.Close();
            RdStrm.Close();

        }

        public void Delete(int mailNumber)
        {
            Data = "DELE " + mailNumber + CRLF;
            szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
            NetStrm.Write(szData, 0, szData.Length);
            string response = RdStrm.ReadLine();
            Status.Add(response);

            if (!StringUtils.Contains(response, "+OK"))
            {
                //TODO write exception
            }
        }

        public string Retrieve(int mailNumber)
        {
            string message = string.Empty;

            string szTemp;
            try
            {
                // retrieve mail with number mail parameter
                Data = "RETR " + mailNumber + CRLF;
                szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
                NetStrm.Write(szData, 0, szData.Length);

                szTemp = RdStrm.ReadLine();
                if (szTemp[0] != '-')
                {

                    while (szTemp != ".")
                    {
                        message += szTemp + CRLF;
                        szTemp = RdStrm.ReadLine();
                    }
                }
                else
                {
                    Status.Add(szTemp);
                }

            }
            catch (InvalidOperationException err)
            {
                Status.Add("Error: " + err.ToString());
            }

            return message;

        }


        public TcpClient Server;
        public NetworkStream NetStrm;
        public StreamReader RdStrm;
        public string Data;
        public byte[] szData;
        public string CRLF = "\r\n";
    }
}