namespace LLama.Web.Services
{

    /// <summary>
    /// Service for managing loading/preloading of models at app startup
    /// </summary>
    /// <typeparam name="T">Type used to identify contexts</typeparam>
    /// <seealso cref="Microsoft.Extensions.Hosting.IHostedService" />
    public class ModelLoaderService : IHostedService 
    {
        private readonly IModelService _modelService;

        /// <summary>
        /// Initializes a new instance of the <see cref="ModelLoaderService"/> class.
        /// </summary>
        /// <param name="modelService">The model service.</param>
        public ModelLoaderService(IModelService modelService)
        {
            _modelService = modelService;
        }


        /// <summary>
        /// Triggered when the application host is ready to start the service.
        /// </summary>
        /// <param name="cancellationToken">Indicates that the start process has been aborted.</param>
        public async Task StartAsync(CancellationToken cancellationToken)
        {
            await _modelService.LoadModels();
        }


        /// <summary>
        /// Triggered when the application host is performing a graceful shutdown.
        /// </summary>
        /// <param name="cancellationToken">Indicates that the shutdown process should no longer be graceful.</param>
        public async Task StopAsync(CancellationToken cancellationToken)
        {
            await _modelService.UnloadModels();
        }
    }
}