using System;
using System.Linq;
using System.Collections.Generic;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using AyaNova.Models;
using AyaNova.Util;

namespace AyaNova.Biz
{

    /// <summary>
    /// Preventive maintenance generator
    /// turn PMs into Work orders
    /// 
    /// </summary>
    internal static class CoreJobPMGenerate
    {
        private static bool IsRunning = false;
        private static ILogger log = AyaNova.Util.ApplicationLogging.CreateLogger("CoreJobPMGenerate");
        private static DateTime lastRun = DateTime.MinValue;


#if (DEBUG)
        private static TimeSpan RUN_EVERY_INTERVAL = new TimeSpan(0, 0, 24);//no more frequently than once every 20 seconds
#else
        private static TimeSpan RUN_EVERY_INTERVAL = new TimeSpan(0, 5, 2);//no more frequently than once every 5 minutes
#endif


        public static async Task DoWorkAsync()
        {
            log.LogTrace("Checking if PMGenerate should run");
            if (IsRunning)
            {
                log.LogTrace("PMGenerate 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($"PMGenerate ran less than {RUN_EVERY_INTERVAL} ago, exiting this cycle");
                return;
            }
            try
            {
                IsRunning = true;
                log.LogDebug("PMGenerate set to RUNNING state and starting now");

                using (AyContext ct = AyaNova.Util.ServiceProviderProvider.DBContext)
                {
                    await PMBiz.GenerateAsync(ct, log);
                }
            }
            catch (Exception ex)
            {
                log.LogError(ex, $"Error processing PMGenerate ");
                 await NotifyEventHelper.AddGeneralNotifyEvent(NotifyEventType.PMGenerationFailed, "PM Generate failure","Preventive Maintenance", ex);
            }
            finally
            {
                log.LogDebug("PMGenerate has completed; setting to not running state and tagging lastRun timestamp");
                lastRun = DateTime.UtcNow;
                IsRunning = false;

            }

        }





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

    }//eoc


}//eons