using BS.Shared.AppSender;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Net;
using System.Net.Mail;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using BS.Shared.Core;
using BS.Shared.Extensions;

namespace BeWo.ServerUtils.Core
{
	public static class MailUtils
	{
		private static readonly Module _GKV_Module = new Module("Gkv", "GKV/EDI/EDAT");
		private static readonly Module _AI_Module = new Module("Ai", "AI");

		private static readonly Dictionary<string, string> _serverMap = new Dictionary<string, string>()
		{
			["WIN-FDL8EJ28T7E"] = "app1.bewoplaner.de",
			["WIN-E38DS2VNNPE"] = "app2.bewoplaner.de",
			["WIN-40R404TI9J0"] = "app3.bewoplaner.de",
			["OWNEROR-8BGG3AK"] = "app4.bewoplaner.de",
			["OWNEROR-K9VRMQT"] = "app5.bewoplaner.de",
			["WIN-1288MG5M1RE"] = "app6.bewoplaner.de",
			["WIN-5H6NO5J7OAT"] = "app7.bewoplaner.de",
			["WIN-A27H847STS6"] = "app8.bewoplaner.de",
		};

		public static bool SendAiModuleErrorMail(string title, string body, string tenant)
			=> SendModuleErrorMail(_AI_Module, title, body, tenant);

		public static bool SendGkvModuleErrorMail(string title, Exception e, string tenant)
			=> SendGkvModuleErrorMail(title, "Exception gefunden: " + e.ToString(), tenant);
		public static bool SendGkvModuleErrorMail(string title, string body, string tenant)
		{
			return SendModuleErrorMail(_GKV_Module, title, body, tenant);
		}

		private static bool SendModuleErrorMail(Module module, string title, string body, string tenant)
		{
			var conn = AppSettingReader.GetSmtpConnectionInfo(module);

			if (!conn.Enabled)
				return false;

			var subject = $"ownSoft Module Error {module.Name}: {title}";
			var toAddress = conn.MailReceiver;
			var senderName = conn.MailSender;
			var senderEMail = conn.MailSender;
			var smtpServer = conn.SmtpServer;
			var smtpUser = conn.SmtpUser;
			var smtpPassword = conn.SmtpPassword;
			var sendAsync = false;

			string tenant_str = "Kunde: " + (tenant ?? "unknown"); 
			body += "\n\n" + tenant_str;

			string server = AppRequestSender.GetServerFromTenant(tenant);
			string server_str = "Kundenserver: " + (server ?? "unkown");
			body += "\n" + server_str;

			string hostname = Dns.GetHostName();
			string hostname_str = "MachineName: " + (hostname ?? "unknown");
			body += "\n\n" + hostname_str;
			
			string server2 = _serverMap.GetValueOrDefault(hostname, "unknown");
			string server2_str = "ServerMap: " + (server2);
			body += "\n" + server2_str;

			return SendEmail(subject, body, toAddress, senderName, senderEMail, smtpServer, smtpUser, smtpPassword, sendAsync);
		}

		private static bool SendEmail(string subject, string body, string toAddress, string fromName, string fromAddress, string smtpServer, string smtpUser, string smtpPassword, bool sendAsync)
		{
			try
			{
				if (!IsValidEmail(toAddress) || !IsValidEmail(fromAddress))
				{
					return false;
				}

				MailMessage message = new MailMessage(fromAddress, toAddress, subject, body);

				if (toAddress != fromAddress)
				{
					message.ReplyToList.Add(new MailAddress(fromAddress, fromName));
				}

				message.BodyEncoding = Encoding.UTF8;
				message.IsBodyHtml = false;

				var mailClient = new SmtpClient(smtpServer, 587) { Credentials = new NetworkCredential(smtpUser, smtpPassword) };
				mailClient.EnableSsl = true;

				if (sendAsync)
				{
					mailClient.SendAsync(message, null);
				}
				else
				{
					mailClient.Send(message);
				}

				return true;
			}
			catch (Exception e)
			{
				return false;
			}
		}

		public static bool IsValidEmail(string email)
		{
			//return Regex.IsMatch(email, @"^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$");

			return Regex.IsMatch(email,
				@"^(?("")("".+?(?<!\\)""@)|(([0-9a-z]((\.(?!\.))|[-!#\$%&'\*\+/=\?\^`\{\}\|~\w])*)(?<=[0-9a-z])@))" +
				@"(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])|(([0-9a-z][-0-9a-z]*[0-9a-z]*\.)+[a-z0-9][\-a-z0-9]{0,22}[a-z0-9]))$",
				RegexOptions.IgnoreCase, TimeSpan.FromMilliseconds(250));
		}

		
	}
}