using AsbCloudDb.Model;
using AsbCloudInfrastructure.Services.DetectOperations;
using AsbCloudInfrastructure.Services;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using System;
using System.Threading.Tasks;
using System.Threading;
using AsbCloudInfrastructure.Background;
using AsbCloudApp.Data.SAUB;
using AsbCloudDb;
using AsbCloudApp.Repositories;
using AsbCloudInfrastructure.Background.PeriodicWorks;

namespace AsbCloudInfrastructure
{
    public class Startup
    {
        public static void BeforeRunHandler(IHost host)
        {
            using var scope = host.Services.CreateScope();
            var provider = scope.ServiceProvider;

            var context = provider.GetRequiredService<IAsbCloudDbContext>();
            context.Database.EnsureCreatedAndMigrated();

            // TODO: Сделать инициализацию кеша телеметрии более явной.
            _ = provider.GetRequiredService<ITelemetryDataCache<TelemetryDataSaubDto>>();
            _ = provider.GetRequiredService<ITelemetryDataCache<TelemetryDataSpinDto>>();

            var backgroundWorker = provider.GetRequiredService<PeriodicBackgroundWorker>();
            backgroundWorker.Add<WorkToDeleteOldReports>(TimeSpan.FromDays(1));
            backgroundWorker.Add<WellInfoService.WorkWellInfoUpdate>(TimeSpan.FromMinutes(30));
            backgroundWorker.Add<WorkOperationDetection>(TimeSpan.FromMinutes(15));
            backgroundWorker.Add<WorkLimitingParameterCalc>(TimeSpan.FromMinutes(30));
            backgroundWorker.Add(MakeMemoryMonitoringWork(), TimeSpan.FromMinutes(1));

            var notificationBackgroundWorker = provider.GetRequiredService<NotificationBackgroundWorker>();
        }

        static Work MakeMemoryMonitoringWork()
        {
            var workAction = (string _, IServiceProvider _, Action<string, double?> _, CancellationToken _) => {
                var bytes = GC.GetTotalMemory(false);
                var bytesString = FromatBytes(bytes);
                System.Diagnostics.Trace.TraceInformation($"Total memory allocated is {bytesString} bytes. DbContext count is:{AsbCloudDbContext.ReferenceCount}");
                return Task.CompletedTask;
            };
            var work = Work.CreateByDelegate("Memory monitoring", workAction);
            return work;
        }

        static string FromatBytes(long bytes)
        {
            const double gigaByte = 1024 * 1024 * 1024;
            const double megaByte = 1024 * 1024;
            const double kiloByte = 1024;
            
            if (bytes > 10 * gigaByte)
                return (bytes / gigaByte).ToString("### ### ###.## Gb");

            if (bytes > 10 * megaByte)
                return (bytes / megaByte).ToString("### ### ###.## Mb");

            if (bytes > 10 * kiloByte)
                return (bytes / megaByte).ToString("### ### ###.## Kb");

            return bytes.ToString("### ### ###");
        }
    }

}