using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;
using Tango.BL;
using Tango.BL.Entities;
using Tango.Core.Commands;
using Tango.MachineStudio.Common.Notifications;
using Tango.MachineStudio.UsersAndRoles.Navigation;
using Tango.SharedUI;

namespace Tango.MachineStudio.UsersAndRoles.ViewModels
{
    public class MainViewVM : ViewModel
    {
        private ObservablesContext _organizationsContext;
        private ObservablesContext _manageContext;
        private ObservablesContext _userContext;
        private UsersAndRolesNavigationManager _navigation;
        private INotificationProvider _notification;

        private ObservableCollection<Organization> _organizations;
        public ObservableCollection<Organization> Organizations
        {
            get { return _organizations; }
            set { _organizations = value; RaisePropertyChangedAuto(); }
        }

        private Organization _selectedOrganization;
        public Organization SelectedOrganization
        {
            get { return _selectedOrganization; }
            set { _selectedOrganization = value; RaisePropertyChangedAuto(); }
        }

        private Organization _managedOrganization;
        public Organization ManagedOrganization
        {
            get { return _managedOrganization; }
            set { _managedOrganization = value; RaisePropertyChangedAuto(); }
        }

        private ObservableCollection<Role> _roles;
        public ObservableCollection<Role> Roles
        {
            get { return _roles; }
            set { _roles = value; RaisePropertyChangedAuto(); }
        }

        private ObservableCollection<Role> _managedUserRoles;
        public ObservableCollection<Role> ManagedUserRoles
        {
            get { return _managedUserRoles; }
            set { _managedUserRoles = value; RaisePropertyChangedAuto(); }
        }

        private User _selectedUser;
        public User SelectedUser
        {
            get { return _selectedUser; }
            set { _selectedUser = value; RaisePropertyChangedAuto(); }
        }

        private User _managedUser;
        public User ManagedUser
        {
            get { return _managedUser; }
            set { _managedUser = value; RaisePropertyChangedAuto(); }
        }

        public RelayCommand ManageOrganizationCommand { get; set; }

        public RelayCommand BackToOrganizationsCommand { get; set; }

        public RelayCommand ManageUserCommand { get; set; }

        public RelayCommand SaveOrganizationCommand { get; set; }

        public RelayCommand AddOrganizationCommand { get; set; }

        public MainViewVM(UsersAndRolesNavigationManager navigation, INotificationProvider notification)
        {
            _navigation = navigation;
            _notification = notification;

            LoadOrganizations();

            ManageOrganizationCommand = new RelayCommand(ManageOrganization, () => SelectedOrganization != null);
            BackToOrganizationsCommand = new RelayCommand(BackToOrganizations);
            ManageUserCommand = new RelayCommand(ManageUser, () => SelectedUser != null);
            SaveOrganizationCommand = new RelayCommand(SaveOrganization);
            AddOrganizationCommand = new RelayCommand(AddOrganization);
        }

        private async void AddOrganization()
        {
            String name = _notification.ShowTextInput("Enter organization name", "Name");

            if (!String.IsNullOrWhiteSpace(name))
            {
                using (_notification.PushTaskItem("Adding new organization..."))
                {
                    Organization org = new Organization();
                    org.Name = name;
                    org.Address = new Address();
                    org.Contact = new Contact();
                    _organizationsContext.Organizations.Add(org);
                    await org.SaveAsync(_organizationsContext);
                    Organizations = _organizationsContext.Organizations.ToObservableCollection();
                    SelectedOrganization = org;
                    ManageOrganization();
                }
            }
        }

        private async void SaveOrganization()
        {
            using (_notification.PushTaskItem("Saving organization address and contact..."))
            {
                ManagedOrganization.Contact.FullName = ManagedOrganization.Contact.FirstName + " " + ManagedOrganization.Contact.LastName;
                await ManagedOrganization.SaveAsync(_manageContext);
                LoadOrganizations();
                SelectedOrganization = Organizations.SingleOrDefault(x => x.Guid == ManagedOrganization.Guid);
            }
        }

        private void ManageUser()
        {
            using (_notification.PushTaskItem("Loading user details..."))
            {
                Task.Factory.StartNew(() =>
                {
                    _userContext = ObservablesContext.CreateDefault();
                    Roles = _manageContext.Roles.ToObservableCollection();
                    ManagedUser = _manageContext.Users.SingleOrDefault(x => x.Guid == SelectedUser.Guid);
                    ManagedUserRoles = ManagedUser.Roles.ToObservableCollection();

                    InvokeUI(() => _navigation.NavigateTo(UsersAndRolesNavigationView.UserManagementView));
                });
            }
        }

        private void BackToOrganizations()
        {
            _navigation.NavigateTo(UsersAndRolesNavigationView.OrganizationSelectionView);
        }

        private void ManageOrganization()
        {
            using (_notification.PushTaskItem("Loading organization..."))
            {
                Task.Factory.StartNew(() =>
                {
                    _manageContext = ObservablesContext.CreateDefault();
                    ManagedOrganization = _manageContext.Organizations.SingleOrDefault(x => x.Guid == SelectedOrganization.Guid);

                    InvokeUI(() => _navigation.NavigateTo(UsersAndRolesNavigationView.OrganizationManagementView));
                });
            }
        }

        private void LoadOrganizations()
        {
            _organizationsContext = ObservablesContext.CreateDefault();
            _organizationsContext.Configuration.LazyLoadingEnabled = false;

            _organizationsContext.Users.ToList();
            _organizationsContext.Contacts.ToList();
            _organizationsContext.Addresses.ToList();
            _organizationsContext.Machines.ToList();

            Organizations = _organizationsContext.Organizations.ToObservableCollection();
        }

        public void OnDropRole(Role role)
        {
            ManagedUser.UsersRoles.Add(new UsersRole()
            {
                Role = role,
                RoleGuid = role.Guid,
                User = ManagedUser,
                UserGuid = ManagedUser.Guid,
            });

            ManagedUserRoles.Add(role);
        }

        protected override void RaisePropertyChangedAuto([CallerMemberName] string caller = null)
        {
            base.RaisePropertyChangedAuto(caller);
            InvalidateRelayCommands();
        }
    }
}