using AS1024.GeoFeed.Core.Interfaces;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

namespace AS1024.GeoFeed.Core.CacheService
{
    public class GeoFeedCacheService : IHostedService
    {
        private readonly ILogger<GeoFeedCacheService> logger;
        private readonly IGeoFeedProvider feedProvider;
        private readonly IHost host;

        public GeoFeedCacheService(ILogger<GeoFeedCacheService> logger,
        IGeoFeedProvider feedProvider,
        IHost host)
        {
            this.logger = logger;
            this.feedProvider = feedProvider;
            this.host = host;
        }

        public Task StartAsync(CancellationToken cancellationToken)
        {
            _ = StartPerioidicSync(cancellationToken);
            return Task.CompletedTask;
        }

        public Task StopAsync(CancellationToken cancellationToken)
        {
            return Task.CompletedTask;
        }

        public async Task<bool> StartPerioidicSync(CancellationToken Token)
        {
            while (!Token.IsCancellationRequested)
            {
                try
                {
                    var scope = host.Services.CreateScope();

                    var persistentCacheProvider =
                        scope.ServiceProvider.GetRequiredService<IGeoFeedPersistentCacheProvider>();

                    var results = await feedProvider.GetGeoFeedDataAsync();
                    await persistentCacheProvider.CacheGeoFeed(results);
                }
                catch (Exception)
                {
                    logger.LogWarning("On disk cache failed to run. Waiting on 30 minutes before retry...");
                }
                await Task.Delay(TimeSpan.FromMinutes(30));
            }

            return false;
        }
    }
}