using System;
using System.Net.Mail;
using System.Text.RegularExpressions;
using System.Threading;
using Server;

namespace Server.Misc
{
	public class Email
	{
		/* In order to support emailing, fill in EmailServer and FromAddress:
		 * Example:
		 *  public static readonly string EmailServer = "mail.domain.com";
		 *  public static readonly string FromAddress = "runuo@domain.com";
		 * 
		 * If you want to add crash reporting emailing, fill in CrashAddresses:
		 * Example:
		 *  public static readonly string CrashAddresses = "first@email.here,second@email.here,third@email.here";
		 * 
		 * If you want to add speech log page emailing, fill in SpeechLogPageAddresses:
		 * Example:
		 *  public static readonly string SpeechLogPageAddresses = "first@email.here,second@email.here,third@email.here";
		 */

		public static readonly string EmailServer = null;
		public static readonly int EmailPort = 25;

		public static readonly string FromAddress = null;
		public static readonly string EmailUsername = null;
		public static readonly string EmailPassword = null;


		public static readonly string CrashAddresses = null;
		public static readonly string SpeechLogPageAddresses = null;

		private static Regex _pattern = new Regex( @"^[a-z0-9.+_-]+@([a-z0-9-]+\.)+[a-z]+$", RegexOptions.Compiled | RegexOptions.IgnoreCase );

		public static bool IsValid( string address )
		{
			if ( address == null || address.Length > 320 )
				return false;

			return _pattern.IsMatch( address );
		}

		private static SmtpClient _Client;

		public static void Configure()
		{
			if ( EmailServer != null )
			{
				_Client = new SmtpClient( EmailServer, EmailPort );
				if ( EmailUsername != null )
				{
					_Client.Credentials = new System.Net.NetworkCredential( EmailUsername, EmailPassword );
				}
			}
		}

		public static bool Send( MailMessage message )
		{
			try
			{
				// .NET relies on the MTA to generate Message-ID header. Not all MTAs will add this header.

				DateTime now = DateTime.UtcNow;
				string messageID = String.Format("<{0}.{1}@{2}>", now.ToString("yyyyMMdd"), now.ToString("HHmmssff"), EmailServer );
				message.Headers.Add("Message-ID", messageID );

				message.Headers.Add("X-Mailer", "RunUO");

				lock ( _Client ) {
					_Client.Send( message );
				}
			}
			catch
			{
				return false;
			}

			return true;
		}

		public static void AsyncSend( MailMessage message )
		{
			ThreadPool.QueueUserWorkItem( new WaitCallback( SendCallback ), message );
		}

		private static void SendCallback( object state )
		{
			MailMessage message = (MailMessage) state;

			if ( Send( message ) )
				Console.WriteLine( "Sent e-mail '{0}' to '{1}'.", message.Subject, message.To );
			else
				Console.WriteLine( "Failure sending e-mail '{0}' to '{1}'.", message.Subject, message.To );
		}
	}
}