using System;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using AyaNova.Models;

namespace AyaNova.Biz
{

    /// <summary>
    /// Notification processor
    /// 
    /// </summary>
    internal static class CoreJobNotify
    {
        private static bool NotifyIsRunning = false;
        private static ILogger log = AyaNova.Util.ApplicationLogging.CreateLogger("CoreJobNotify");
        private static DateTime lastRun = DateTime.MinValue;
        private static TimeSpan DELETE_AFTER_AGE = new TimeSpan(90, 0, 0, 0);
        private static TimeSpan RUN_EVERY_INTERVAL = new TimeSpan(0, 2, 0);//once every 2 minutes minimum
        private static DateTime lastNotifyHealthCheckSentLocal = DateTime.MinValue;
        private static TimeSpan TS_24_HOURS = new TimeSpan(24, 0, 0);//used to ensure daily ops happen no more than that


        ////////////////////////////////////////////////////////////////////////////////////////////////
        // DoSweep
        //
        public static async Task DoWorkAsync()
        {
            log.LogTrace("Checking if Notify should run");
            if (NotifyIsRunning)
            {
                log.LogTrace("Notify is running already exiting this cycle");
                return;
            }
            //This will get triggered roughly every minute, but we don't want to deliver that frequently
            if (DateTime.UtcNow - lastRun < RUN_EVERY_INTERVAL)
            {
                log.LogTrace($"Notify ran less than {RUN_EVERY_INTERVAL}, exiting this cycle");
                return;
            }
            try
            {
                NotifyIsRunning = true;
                log.LogTrace("Notify set to RUNNING state and starting now");

                //NotifyHealthCheck processing
                //Note this deliberately uses LOCAL time in effort to deliver the health check first thing in the morning for workers
                //However if server is on UTC already then that's what is used, there is no adjustment
                DateTime dtNowLocal = DateTime.Now;
                if (dtNowLocal - lastNotifyHealthCheckSentLocal > TS_24_HOURS)
                {
                    //are we in the 7th to 9th hour?
                    if (dtNowLocal.Hour > 6 && dtNowLocal.Hour < 10)
                    {
                        log.LogTrace("Notify health check submitted to subscribers");
                        await NotifyEventProcessor.AddGeneralNotifyEvent(NotifyEventType.NotifyHealthCheck, "OK");
                        lastNotifyHealthCheckSentLocal = dtNowLocal;
                    }
                }




                using (AyContext ct = AyaNova.Util.ServiceProviderProvider.DBContext)
                {
                    //select all jobs with no deliver date or deliver date no longer in future

                    //IMPLEMENTATION NOTES:  This code
                    // finds the events in NotifyEvent
                    // check subscription to determine if the age related ones are deliverable now
                    // check subscriptions for each delivery type, i.e. there might be both smtp and inapp separately for the same event so it needs to know that and deliver accordingly
                    // remove the notify event after it's processed



                    //Older notes:
                    //### PLAN if it's an smtp delivery that fails and it's to someone who can be delivered in app then it should send an inapp notification of 
                    //delivery failure and still delete the smtp delivery
                    //If it's not possible to notify the person via in app of the failed smtp then perhaps it notifies OPS personnel and biz admin personnel
                    //NEW NOTIFICATION SUBSCRIPTION EVENT TYPE:
                    //OPERATIONS_PROBLEMS - backup, notifications, out of memory, what have you, anyone can subscribe to it regardless of rights
                    //this is just to let people know there is a problem
                    //todo: create message here if not already set?
                    //todo: generate and attach report here?


                }
            }
            catch (Exception ex)
            {

            }
            finally
            {
                log.LogTrace("Notify is done setting to not running state and tagging lastRun timestamp");
                lastRun = DateTime.UtcNow;
                NotifyIsRunning = false;
            }

        }



        /////////////////////////////////////////////////////////////////////

    }//eoc


}//eons