using System;
using System.Collections.Generic;
using System.Linq;

using C4IT.FASD.Base;
using C4IT.Logging;

using FasdDesktopUi.Basics;

using static C4IT.Logging.cLogManager;

namespace FasdDesktopUi.Basics.Helper
{
    internal static class TicketExternalLinkHelper
    {
        private const string DefaultTicketActivityType = "SPSActivityTypeTicket";

        internal static bool TryOpenTicketRelationExternally(cF4sdApiSearchResultRelation relation)
        {
            try
            {
                if (relation == null || relation.Type != enumF4sdSearchResultClass.Ticket)
                    return false;

                // check how we should open this ticket (intern, extern or both)
                var ticketType = GetTicketType(relation);
                var processing = ShouldOpenExternally(ticketType);

                // check if we have a valid user id in the id list => if not we could open this ticket only extern.
                var hasUser = HasValidUserIdentity(relation);
                if (!hasUser)
                    processing = enumTicketProcessing.Extern;

                if (processing == enumTicketProcessing.Intern)
                    return false;

                var m42Server = cCockpitConfiguration.Instance?.m42ServerConfiguration?.Server;
                if (!TryGetTicketLink(relation, m42Server, out var ticketLink))
                {
                    LogEntry($"Could not resolve an external Matrix42 link for ticket '{relation.DisplayName ?? relation.Name}'.", LogLevels.Warning);
                    return false;
                }

                new cBrowsers().Start("default", ticketLink);

                return processing == enumTicketProcessing.Extern;
            }
            catch (Exception ex)
            {
                LogException(ex);
            }

            return false;
        }

        internal static bool HasValidUserIdentity(cF4sdApiSearchResultRelation relation)
        {
            return relation?.Identities?.Any(identity =>
                identity.Class == enumFasdInformationClass.User && identity.Id != Guid.Empty) == true;
        }

        internal static bool TryGetTicketLink(cF4sdApiSearchResultRelation relation, string m42Server, out string ticketLink)
        {
            ticketLink = null;
            if (relation == null || relation.Type != enumF4sdSearchResultClass.Ticket)
                return false;

            if (TryGetHttpLink(relation, "TicketLink", out ticketLink) ||
                TryGetHttpLink(relation, "DirectLinkPreview", out ticketLink))
            {
                return true;
            }

            if (relation.id == Guid.Empty || string.IsNullOrWhiteSpace(m42Server))
                return false;

            var server = m42Server.Trim();
            if (!server.Contains("://"))
                server = $"https://{server}";

            if (!Uri.TryCreate(server, UriKind.Absolute, out var serverUri) ||
                (serverUri.Scheme != Uri.UriSchemeHttp && serverUri.Scheme != Uri.UriSchemeHttps))
            {
                return false;
            }

            var activityType = GetActivityType(relation);
            var encodedActivityType = Uri.EscapeDataString(activityType);
            ticketLink = $"{serverUri.Scheme}://{serverUri.Authority}/wm/app-ServiceDesk/notSet/preview-object/{encodedActivityType}/{relation.id:D}/0/";
            return true;
        }

        private static bool TryGetHttpLink(cF4sdApiSearchResultRelation relation, string key, out string ticketLink)
        {
            ticketLink = null;
            if (relation?.Infos?.TryGetValue(key, out var configuredLink) != true || string.IsNullOrWhiteSpace(configuredLink))
                return false;

            if (!Uri.TryCreate(configuredLink, UriKind.Absolute, out var linkUri) ||
                (linkUri.Scheme != Uri.UriSchemeHttp && linkUri.Scheme != Uri.UriSchemeHttps))
            {
                return false;
            }

            ticketLink = linkUri.AbsoluteUri;
            return true;
        }

        private static string GetActivityType(cF4sdApiSearchResultRelation relation)
        {
            if (relation?.Infos?.TryGetValue("ActivityType", out var activityType) == true && !string.IsNullOrWhiteSpace(activityType))
                return activityType.Trim();

            if (relation?.Infos?.TryGetValue("TicketType", out var ticketTypeValue) == true &&
                Enum.TryParse(ticketTypeValue, true, out enumTicketType ticketType))
            {
                switch (ticketType)
                {
                    case enumTicketType.Incident:
                        return "SPSActivityTypeIncident";
                    case enumTicketType.ServiceRequest:
                        return "SPSActivityTypeServiceRequest";
                }
            }

            return DefaultTicketActivityType;
        }

        private static enumTicketType GetTicketType(cF4sdApiSearchResultRelation relation)
        {
            if (relation?.Infos != null && relation.Infos.TryGetValue("TicketType", out var ticketTypeValue))
            {
                if (Enum.TryParse<enumTicketType>(ticketTypeValue, true, out var ticketType))
                    return ticketType;
            }
            return enumTicketType.Ticket;
        }

        private static enumTicketProcessing ShouldOpenExternally(enumTicketType ticketType)
        {
            var ticketConfig = cFasdCockpitConfig.Instance?.Global?.TicketConfiguration;
            if (ticketConfig == null)
                return enumTicketProcessing.Extern;

            if (ticketConfig.TicketProcessing?.TryGetValue(ticketType, out var processing) == true)
                return processing;

            return ticketConfig.DefaultProcessing;
        }
    }
}