using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Tango.BL;
using Tango.Core;
using Tango.Core.DI;
using Tango.Core.Helpers;
using Tango.PPC.Common;
using Tango.PPC.Common.Application;
using Tango.PPC.Common.Authentication;
using Tango.PPC.Common.MachineSetup;
using Tango.PPC.Common.Modules;
using Tango.PPC.Common.Navigation;
using Tango.PPC.Common.Notifications;
using Tango.PPC.Common.Notifications.NotificationItems;
using Tango.PPC.Jobs;
using Tango.SharedUI;
using System.Data.Entity;
using Tango.BL.Enumerations;
using Tango.BL.Builders;

namespace Tango.PPC.UI.ViewModels
{
    /// <summary>
    /// Represents the PPC loading splash screen view model.
    /// </summary>
    /// <seealso cref="Tango.PPC.Common.PPCViewModel" />
    public class LoadingViewVM : PPCViewModel
    {
        /// <summary>
        /// Gets or sets the module loader.
        /// </summary>
        [TangoInject]
        public IPPCModuleLoader ModuleLoader { get; set; }

        private bool _isLoading;
        /// <summary>
        /// Gets or sets a value indicating whether this instance is loading.
        /// </summary>
        public bool IsLoading
        {
            get { return _isLoading; }
            set { _isLoading = value; RaisePropertyChangedAuto(); }
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="LoadingViewVM"/> class.
        /// </summary>
        public LoadingViewVM(IPPCApplicationManager applicationManager)
        {
            if (!DesignMode)
            {
                Task.Delay(1000).ContinueWith((x) => { IsLoading = true; });
            }

            applicationManager.ApplicationInitializationError += ApplicationManager_ApplicationInitializationError;
        }

        private void ApplicationManager_ApplicationInitializationError(object sender, Exception ex)
        {
            InvokeUI(() =>
            {
                NavigationManager.NavigateWithObject<Exception>(NavigationView.LoadingErrorView, ex);
                IsLoading = false;
            });
        }

        /// <summary>
        /// Called when the application has been started.
        /// </summary>
        public async override void OnApplicationStarted()
        {
            using (ObservablesContext db = ObservablesContext.CreateDefault())
            {
                var machine = await db.Machines.FirstAsync();

                if (db.Users.Count() == 1 || machine.AutoLogin)
                {
                    var user = await new UserBuilder(db).SetFirst().WithRolesAndPermissions().BuildAsync();

                    if (!user.HasRole(Roles.PPCUser))
                    {
                        var role = db.Roles.Single(x => x.Code == (int)Roles.PPCUser);
                        user.Roles.Add(role);
                        db.UsersRoles.Add(new BL.Entities.UsersRole()
                        {
                            User = user,
                            Role = role,
                        });
                        await db.SaveChangesAsync();
                    }

                    LogManager.Log($"Application started. Single user/Auto login detected ({user.Email}). Skipping LoginView...");
                    await AuthenticationProvider.Login(user.Email, user.Password, false);
                    IsLoading = false;
                }
                else
                {
                    LogManager.Log("Application started. Navigating to LoginView...");
                    await NavigationManager.NavigateTo(NavigationView.LoginView);
                    IsLoading = false;
                }
            }
        }
    }
}