using Avalonia_Services.Services.FileLibrary;

namespace Avalonia_API.Services
{
    public sealed class FileLibraryScanHostedService(IServiceScopeFactory scopeFactory, ILogger<FileLibraryScanHostedService> logger)
        : BackgroundService
    {
        private static readonly TimeSpan Interval = TimeSpan.FromMinutes(1);

        protected override async Task ExecuteAsync(CancellationToken stoppingToken)
        {
            await ScanAsync(stoppingToken);

            using var timer = new PeriodicTimer(Interval);
            while (await timer.WaitForNextTickAsync(stoppingToken))
            {
                await ScanAsync(stoppingToken);
            }
        }

        private async Task ScanAsync(CancellationToken cancellationToken)
        {
            try
            {
                await using var scope = scopeFactory.CreateAsyncScope();
                var scanner = scope.ServiceProvider.GetRequiredService<IFileLibraryService>();
                await scanner.ScanDueRootsAsync(cancellationToken);
            }
            catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested)
            {
            }
            catch (Exception ex)
            {
                logger.LogWarning(ex, "文件库定时扫描失败。");
            }
        }
    }
}