using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using TINK.Model.Connector;

namespace TINK.Model.User.Account
{
	public class StoreLegacy : IStore
	{
		/// <summary>
		/// Holds the name of the application.
		/// </summary>
		private const string M_STR_APPNAME = "TINKApp";

		/// <summary> Holds the id of the session. </summary>
		private const string KEY_SESSIONID = "SessionId";

		/// <summary> Holds the id of the session. </summary>
		private const string KEY_GROUP = "Group";

		/// <summary> Holds the id of the session. </summary>
		private const string KEY_DEBUGLEVEL = "DebugLevel";

		public StoreLegacy(string copriHostHash)
		{
			m_strCopriHostHash = copriHostHash
				?? throw new ArgumentException("Can not construct account object. Copri hash must not be null.");
		}

		private string m_strCopriHostHash;

		/// <summary>
		/// Reads mail address and password from account store.
		/// </summary>
		/// <returns></returns>
		public async Task<IAccount> Load()
		{
#if !WINDOWS_UWP
#if !__IOS__
			var xamAccountStore = Xamarin.Auth.AccountStore.Create("System.Char[]").FindAccountsForService($"{M_STR_APPNAME}_{m_strCopriHostHash}").FirstOrDefault();
#else
			var xamAccountStore = Xamarin.Auth.AccountStore.Create().FindAccountsForService($"{M_STR_APPNAME}_{m_strCopriHostHash}").FirstOrDefault();
#endif
			if (xamAccountStore == null)
			{
				// Nothing t do if account cannot be accessed.
				return new EmptyAccount();
			}

			return new Account(
				xamAccountStore.Username,
				string.Empty,
				xamAccountStore.Properties.ContainsKey(KEY_SESSIONID) ? xamAccountStore.Properties[KEY_SESSIONID] : null,
				xamAccountStore.Properties.ContainsKey(KEY_GROUP) && !string.IsNullOrEmpty(xamAccountStore.Properties[KEY_GROUP]) ? JsonConvert.DeserializeObject<IEnumerable<string>>(xamAccountStore.Properties[KEY_GROUP]) : new string[0],
				xamAccountStore.Properties.ContainsKey(KEY_DEBUGLEVEL) && !string.IsNullOrEmpty(xamAccountStore.Properties[KEY_DEBUGLEVEL]) ? Permissions.Parse<Permissions>(xamAccountStore.Properties[KEY_DEBUGLEVEL]) : Permissions.None);
#else
			return new Account(
                string.Empty,
                string.Empty,
                string.Empty,
                new List<string>(),
                null);

#endif
		}

		/// <summary>
		/// Writes mail address and password to account store.
		/// </summary>
		/// <param name="account"></param>
		public async Task Save(IAccount account)
		{
#if !WINDOWS_UWP
			Xamarin.Auth.Account xamAccount = new Xamarin.Auth.Account
			{
				Username = account.Mail
			};

			xamAccount.Properties.Add(KEY_SESSIONID, account?.SessionCookie);
			xamAccount.Properties.Add(KEY_GROUP, JsonConvert.SerializeObject(account?.Group ?? new string[0]));
			xamAccount.Properties.Add(KEY_DEBUGLEVEL, account.DebugLevel.ToString());
#if !__IOS__
			Xamarin.Auth.AccountStore.Create("System.Char[]").Save(xamAccount, $"{M_STR_APPNAME}_{m_strCopriHostHash}");
#else
			Xamarin.Auth.AccountStore.Create().Save(xamAccount, $"{M_STR_APPNAME}_{m_strCopriHostHash}");
#endif
#endif
		}

		/// <summary>
		/// Deletes mail address and password from account store.
		/// </summary>
		public IAccount Delete(IAccount account)
		{
#if !WINDOWS_UWP
#if !__IOS__
			var xamAccountStore = Xamarin.Auth.AccountStore.Create("System.Char[]").FindAccountsForService($"{M_STR_APPNAME}_{m_strCopriHostHash}").FirstOrDefault();
#else
			var xamAccountStore = Xamarin.Auth.AccountStore.Create().FindAccountsForService($"{M_STR_APPNAME}_{m_strCopriHostHash}").FirstOrDefault();
#endif
			if (xamAccountStore == null)
			{
				return new EmptyAccount();
			}
#if !__IOS__
			Xamarin.Auth.AccountStore.Create("System.Char[]").Delete(xamAccountStore, $"{M_STR_APPNAME}_{m_strCopriHostHash}");
#else
			Xamarin.Auth.AccountStore.Create().Delete(xamAccountStore, $"{M_STR_APPNAME}_{m_strCopriHostHash}");
#endif
#endif
			return new EmptyAccount();
        }
    }
}