using BotSharp.Abstraction.Infrastructures.Events;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

namespace BotSharp.Core.Crontab.Services;

public class CrontabEventSubscription : BackgroundService
{
    private readonly ILogger _logger;
    private readonly IServiceProvider _services;

    public CrontabEventSubscription(IServiceProvider services, ILogger<CrontabEventSubscription> logger)
    {
        _logger = logger;
        _services = services;
    }

    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        _logger.LogInformation("Crontab event subscription background service is running.");

        using (var scope = _services.CreateScope())
        {
            var publisher = scope.ServiceProvider.GetService<IEventPublisher>();
            if (publisher == null)
            {
                return;
            }
            var subscriber = scope.ServiceProvider.GetRequiredService<IEventSubscriber>();
            var cron = scope.ServiceProvider.GetRequiredService<ICrontabService>();
            var crons = await cron.GetCrontable();
            foreach (var item in crons)
            {
                _ = Task.Run(async () =>
                {
                    // Clean unhandled messages
                    await publisher.RemoveAsync($"Crontab:{item.Title}", count: 100);

                    await subscriber.SubscribeAsync($"Crontab:{item.Title}",
                        "Crontab",
                        port: 0,
                        priorityEnabled: false, 
                        async (sender, args) =>
                        {
                            var scope = _services.CreateScope();
                            cron = scope.ServiceProvider.GetRequiredService<ICrontabService>();
                            await cron.ScheduledTimeArrived(item);
                        }, 
                        stoppingToken: stoppingToken);
                });
            }
        }
    }
}