using System;
using System.Collections.Generic;
using System.Globalization;
using System.Threading.Tasks;
using Windows.Storage;
using Windows.UI.Xaml;

namespace FoxTube.Services
{
	public static class Storage
	{
		public static event EventHandler<Settings> SettingsChanged;

		public static StorageFolder Folder => ApplicationData.Current.RoamingFolder;
		public static ApplicationDataContainer Registry { get; } = ApplicationData.Current.RoamingSettings;

		private static readonly Dictionary<Settings, object> _defaultSettings = new Dictionary<Settings, object>
		{
			{ Settings.Theme, ElementTheme.Default },
			{ Settings.UILanguage, GetDefaultLanguage() },
			{ Settings.RelevanceLanguage, GetDefaultLanguage() },
			{ Settings.PromptFeedback, true },
			{ Settings.PromptReview, true },
			{ Settings.AllowAnalytics, true }
		};

		public enum Settings
		{
			/// <summary>
			/// ElementTheme
			/// </summary>
			Theme,
			/// <summary>
			/// string
			/// </summary>
			UILanguage,
			/// <summary>
			/// string
			/// </summary>
			RelevanceLanguage,
			/// <summary>
			/// string
			/// </summary>
			DefaultDownloadsFolder,
			/// <summary>
			/// bool
			/// </summary>
			PromptFeedback,
			/// <summary>
			/// bool
			/// </summary>
			PromptReview,
			/// <summary>
			/// bool
			/// </summary>
			AllowAnalytics,
			/// <summary>
			/// string
			/// </summary>
			Region
		}

		public enum Metrics
		{
			/// <summary>
			/// TimeSpan
			/// </summary>
			Uptime
		}


		public static void SetValue(Settings key, object value)
		{
			Registry.Values[$"{key.GetType().Name}.{key}"] = value;
			SettingsChanged?.Invoke(value, key);
		}
		public static void SetValue(Metrics key, object value) =>
			Registry.Values[$"{key.GetType().Name}.{key}"] = value;

		public static T GetValue<T>(Settings key) =>
			(T)(Registry.Values[$"{key.GetType().Name}.{key}"] ?? (_defaultSettings.ContainsKey(key) ? _defaultSettings[key] : null));
		public static T GetValue<T>(Metrics key) =>
			(T)Registry.Values[$"{key.GetType().Name}.{key}"];


		private static string GetDefaultLanguage()
		{
			if (CultureInfo.InstalledUICulture.TwoLetterISOLanguageName.Belongs("ua", "ru", "by", "kz", "kg", "md", "lv", "ee"))    //Languages for Russian-speaking countries
				return "ru-RU";
			else
				return "en-US";
		}

		public static async Task ResetStorage()
		{
			Registry.Values.Clear();
			foreach (IStorageItem i in await Folder.GetItemsAsync())
				await i.DeleteAsync();
		}
	}
}