using Microsoft.AspNetCore.Localization;

using PrivaPub.StaticServices;

using System.Globalization;

namespace PrivaPub.Services
{
	public class RequestLocalizationOptionsService
	{
		RequestLocalizationOptions RequestLocalizationOptions { get; set; }
		readonly AppConfigurationService AppConfigurationService;

		public RequestLocalizationOptionsService(AppConfigurationService appConfigurationService)
		{
			AppConfigurationService = appConfigurationService;
		}

		public async Task<RequestLocalizationOptions> Get()
		{
			if (RequestLocalizationOptions != default) return RequestLocalizationOptions;
			if (AppConfigurationService.AppConfiguration == default)
				await AppConfigurationService.Init();

			RequestLocalizationOptions = new RequestLocalizationOptions();
			var cultures = AppConfigurationService
										.AppConfiguration
										.SupportedLanguages
										.Select(sl => new CultureInfo(sl))
										.ToArray();
			RequestLocalizationOptions.DefaultRequestCulture = new(cultures.First(), cultures.First());
			RequestLocalizationOptions.SupportedCultures = cultures;
			RequestLocalizationOptions.SupportedUICultures = cultures;
			RequestLocalizationOptions.RequestCultureProviders = new IRequestCultureProvider[] {
						new AcceptLanguageHeaderRequestCultureProvider { Options = RequestLocalizationOptions }
					};
			RequestLocalizationOptions.ApplyCurrentCultureToResponseHeaders = true;

			return RequestLocalizationOptions;
		}
	}
}