ServerInfoVM.cs

using System;
using System.ComponentModel;
using System.Linq;
using System.Runtime.Serialization;

namespace d2mSoftware
{
    [Serializable]
    public class ServerInfoVm : INotifyPropertyChanged, IDataErrorInfo
    {
        public string FullServerAddress { get { return "https://" + ServerAddress + ":" + ServerPort; } }

        #region Property Changes

        public void NotifyPropertyChanged(string _property)
        {
            OnPropertyChanged(_property);
        }

        public event PropertyChangedEventHandler PropertyChanged;

        // Create the OnPropertyChanged method to raise the event 
        protected void OnPropertyChanged(string name)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(name));
            }
        }

        #endregion

        #region UI Elements Enabled Controllers

        public bool AllowRememberPassword { get; set; }

        public bool AllowDelete { get; set; }

        #endregion

        #region Server Info Values

        public bool LoginThisServer { get; set; }

        public string ServerName
        {
            get { return _serverName; }
            set
            {
                _serverName = value;
                OnPropertyChanged("ServerName");
            }
        }
        public string ServerPort { get; set; }
        public string Username { get; set; }
        public string Password { get; set; }

        public bool RememberUsername { get; set; }
        public bool RememberPassword { get; set; }
        
        public string ServerAddress
        {
            get { return _serverAddress; }
            set { _serverAddress = value.Replace("https://", "").Replace("http://", ""); } 
        }

        private string _serverName;
        private string _serverAddress;

        
        #endregion

        #region C'Tors

        public ServerInfoVm()
        {
            AllowRememberPassword = false;
            RememberUsername = true;
        }
        public ServerInfoVm ShallowCopy()
        {
            return (ServerInfoVm)MemberwiseClone();
        }

        public ServerInfoVm(string name, string address, string port, string username, string password, bool rememberUsername, bool rememberPassword, bool allowRememberPassword)
        {
            ServerName = name;
            ServerAddress = address;
            ServerPort = port;

            Username = username;
            Password = password;

            RememberUsername = rememberUsername;
            RememberPassword = rememberPassword;

            AllowRememberPassword = allowRememberPassword;
        }

        #endregion

        #region IDataErrorInfo Members

        public string Error
        {
            get { return this[null]; }
        }

        public string this[string propertyName]
        {
            get
            {
                string result = string.Empty;
                propertyName = propertyName ?? string.Empty;

                if (propertyName == string.Empty || propertyName == "ServerName")
                {
                    if (string.IsNullOrEmpty(this.ServerName))
                        result += "Server name is required" + Environment.NewLine;

                    if (!string.IsNullOrEmpty(this.ServerName) && LoginVm.Current.InstacomServers.Any(item => item != this && item.ServerName == this.ServerName))
                        result += "Server name must be unique" + Environment.NewLine;
                }
                    
                if (propertyName == string.Empty || propertyName == "ServerAddress")
                    if (string.IsNullOrEmpty(this.ServerAddress))
                        result += "Server address is required" + Environment.NewLine;

                if (propertyName == string.Empty || propertyName == "ServerPort")
                {
                    double n;
                    if (string.IsNullOrEmpty(this.ServerPort) || !Double.TryParse(this.ServerPort, out n))
                        result += "Server port must be numeric" + Environment.NewLine;
                }
                
                if (propertyName == string.Empty || propertyName == "Username")
                    if (string.IsNullOrEmpty(this.Username))
                        result += "Username is required" + Environment.NewLine;

                return result.TrimEnd();
            }
        }

        #endregion
    }
}

ServerInfoWindow.xaml.cs

using System;
using System.Collections.Specialized;
using System.Windows.Media;
using System.Net;
using System.Threading;
using System.Windows;
using System.Windows.Input;

namespace d2mSoftware.Windows
{
    public partial class ServerInfoWindow
    {
        private readonly ServerInfoVm _serverInfoVm = new ServerInfoVm();
        private readonly bool _add;

        #region C'Tors

        public ServerInfoWindow()
        {
            InitializeComponent();

            DataContext = _serverInfoVm;

            Title = "Add Server";

            Loaded += ServerInfo_Loaded;

            _add = true;
        }

        public ServerInfoWindow(ServerInfoVm serverInfoVM)
        {
            InitializeComponent();

            _serverInfoVm = serverInfoVM;

            DataContext = _serverInfoVm;

            Loaded += ServerInfo_Loaded;

            _serverInfoVm.AllowDelete = true;

            if (!String.IsNullOrEmpty(_serverInfoVm.Password))
                TxtPassword.Password = "aaaaaaaaa";

            Title = "Edit Server";
        }

        #endregion

        public void TestCredentials(ServerInfoVm serverInfoVm)
        {
            try
            {
                var postData = new NameValueCollection { { "username", serverInfoVm.Username }, { "password", serverInfoVm.Password } };

                using (var wb = new WebClient())
                {
                    byte[] rawResponse = wb.UploadValues(serverInfoVm.FullServerAddress + Helper.AuthPostUrl + "TestLogin", "POST", postData);
                    bool response = Convert.ToBoolean(wb.Encoding.GetString(rawResponse));

                    Application.Current.Dispatcher.Invoke((Action) delegate
                    {
                        CredentialsTestSpinner.Visibility = Visibility.Hidden;
                        TxtCredentialsTestResult.Text = response ? char.ConvertFromUtf32(0xf00c) : char.ConvertFromUtf32(0xf00d);
                        TxtCredentialsTestResult.Foreground = response ? Brushes.Green : Brushes.Red;
                    });
                }
            }
            catch (Exception ex)
            {
                Application.Current.Dispatcher.Invoke((Action) delegate
                {
                    CredentialsTestSpinner.Visibility = Visibility.Hidden;
                    TxtCredentialsTestResult.Text = char.ConvertFromUtf32(0xf00d);
                    TxtCredentialsTestResult.Foreground = Brushes.Red;
                });
         
                Helper.LogMan.Error("ServerInfoWindow:TestCredentials ex: " + ex.Message);
            }

        }

        public void ForgotPost(string type, ServerInfoVm serverInfoVM)
        {
            string response = "Error";

            try
            {
                var postData = new NameValueCollection { { "id", serverInfoVM.Username }, { "passType", type } };

                using (var wb = new WebClient())
                {
                    byte[] rawResponse = wb.UploadValues(serverInfoVM.FullServerAddress + Helper.AuthPostUrl + "ChangePassKeyRequest", "POST", postData);
                    response = wb.Encoding.GetString(rawResponse);

                    Application.Current.Dispatcher.Invoke((Action) delegate
                    {
                        ForgotKeySpinner.Visibility = Visibility.Hidden;
                        ForgotPasswordSpinner.Visibility = Visibility.Hidden;

                        if (Enum.IsDefined(typeof(LoginReturn), response))
                        {
                            if (response == "OK")
                            {
                                TxtForgotResult.Text = "Check Email";
                                TxtForgotResult.Foreground = Brushes.Green;
                            }
                            else
                            {
                                TxtForgotResult.Text = response;
                                TxtForgotResult.Foreground = Brushes.Red;
                            }
                        }
                    });
                }
            }
            catch (Exception ex)
            {
                Application.Current.Dispatcher.Invoke((Action)delegate
                {
                    ForgotKeySpinner.Visibility = Visibility.Hidden;
                    ForgotPasswordSpinner.Visibility = Visibility.Hidden;
                    TxtForgotResult.Text = "Error";
                    TxtForgotResult.Foreground = Brushes.Red;
                });

                Helper.LogMan.Error("PostHelper:ForgotPost ex: " + ex.Message);
            }
        }

        void ServerInfo_Loaded(object sender, RoutedEventArgs e)
        {
            if (String.IsNullOrEmpty(TxtUsername.Text) && !String.IsNullOrEmpty(TxtServerName.Text))
                TxtUsername.Focus();
            else if (String.IsNullOrEmpty(TxtPassword.Password) && !String.IsNullOrEmpty(TxtServerName.Text))
                TxtPassword.Focus();
            else
            {
                TxtServerName.Focus();
                TxtServerName.Select(TxtServerName.Text.Length, 0);    
            }

            TxtPassword.PasswordChanged += TxtPassword_OnPasswordChanged;
        }

        private void BtnSave_OnClick(object sender, RoutedEventArgs e)
        {
            if (!ServerValidator.Validate())
                ServerValidator.GetFirstInvalidElement().Focus();
            else
            {
                SaveServerInfo();
                Close();    
            }
        }

        private void SaveServerInfo()
        {
            if (_add)
                LoginVm.Current.InstacomServers.Add(_serverInfoVm);

            RebuildProperties();
        }

        private void RebuildProperties()
        {
            Application.Current.Dispatcher.Invoke((Action) delegate
            {

                if (Properties.Settings.Default.Servers == null)
                    Properties.Settings.Default.Servers = new StringCollection();
                else
                    Properties.Settings.Default.Servers.Clear();

                foreach (var vm in LoginVm.Current.InstacomServers)
                {
                    var username = vm.RememberUsername ? vm.Username : "";
                    var password = vm.RememberPassword ? vm.Password : "";

                    var vmClone = new ServerInfoVm(vm.ServerName, vm.ServerAddress, vm.ServerPort, username, password, vm.RememberUsername, vm.RememberPassword, vm.AllowRememberPassword);

                    Properties.Settings.Default.Servers.Add(Helper.JSS.Serialize(vmClone));
                }

                Properties.Settings.Default.Save();
            });
        }

        private void BtnCancel_OnClick(object sender, RoutedEventArgs e)
        {
            Close();
        }

        private void BtnDelete_OnClick(object sender, RoutedEventArgs e)
        {
            DeleteServerInfo();
            Close();
        }

        private void DeleteServerInfo()
        {
            Application.Current.Dispatcher.Invoke((Action)delegate
            {
                LoginVm.Current.InstacomServers.Remove(_serverInfoVm);
                RebuildProperties();
                Properties.Settings.Default.Save();
            });
        }

        private void TestServer()
        {
            try
            {
                var webRequest = (HttpWebRequest)WebRequest.Create(_serverInfoVm.FullServerAddress + "/InstacomServer/SignalR/negotiate");
                webRequest.AllowAutoRedirect = false;
                var response = (HttpWebResponse)webRequest.GetResponse();
                
                Application.Current.Dispatcher.Invoke((Action)delegate
                {
                    ServerTestSpinner.Visibility = Visibility.Hidden;
                    TxtServerTestResult.Text = response.StatusCode == HttpStatusCode.OK ? char.ConvertFromUtf32(0xf00c) : char.ConvertFromUtf32(0xf00d);
                    TxtServerTestResult.Foreground = response.StatusCode == HttpStatusCode.OK ? Brushes.Green : Brushes.Red;
                });
            }
            catch (Exception ex)
            {
                Application.Current.Dispatcher.Invoke((Action)delegate
                {
                    ServerTestSpinner.Visibility = Visibility.Hidden;
                    TxtServerTestResult.Text = char.ConvertFromUtf32(0xf00d);
                    TxtServerTestResult.Foreground = Brushes.Red;
                });

                Helper.LogMan.Error("ServerInfoWindow:TestServer ex: " + ex.Message);
            }
        }

        private void BtnTestServer_Click(object sender, RoutedEventArgs e)
        {
            if (!ServerValidator.Validate())
                ServerValidator.GetFirstInvalidElement().Focus();
            else
            {
                TxtServerTestResult.Text = "";
                ServerTestSpinner.Visibility = Visibility.Visible;
                new Thread(TestServer).Start();
            }
        }

        private void TxtPassword_OnPasswordChanged(object sender, RoutedEventArgs e)
        {
            _serverInfoVm.Password = TxtPassword.Password;
        }

        private void BtnForgotPassword_OnPreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            if (!ServerValidator.Validate())
                ServerValidator.GetFirstInvalidElement().Focus();
            else if (!CredentialsValidator.Validate())
                CredentialsValidator.GetFirstInvalidElement().Focus();
            else
            {
                TxtForgotResult.Text = "";
                ForgotPasswordSpinner.Visibility = Visibility.Hidden;
                var thread = new Thread(() => ForgotPost("password", _serverInfoVm));
                thread.Start();
            }
        }

        private void BtnForgotKey_OnPreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            if (!ServerValidator.Validate())
                ServerValidator.GetFirstInvalidElement().Focus();
            else if (!CredentialsValidator.Validate())
                CredentialsValidator.GetFirstInvalidElement().Focus();
            else
            {
                TxtForgotResult.Text = "";
                ForgotKeySpinner.Visibility = Visibility.Hidden;
                var thread = new Thread(() => ForgotPost("key", _serverInfoVm));
                thread.Start();
            }
        }

        private void BtnTestCredentials_OnClick(object sender, RoutedEventArgs e)
        {
            if (!ServerValidator.Validate())
                ServerValidator.GetFirstInvalidElement().Focus();
            else if (!CredentialsValidator.Validate())
                CredentialsValidator.GetFirstInvalidElement().Focus();
            else
            {
                TxtCredentialsTestResult.Text = "";
                TxtForgotResult.Text = "";
                CredentialsTestSpinner.Visibility = Visibility.Visible;

                var thread = new Thread(() => TestCredentials(_serverInfoVm));
                thread.Start();    
            }
        }
    }
}

ServerWindow.xaml

<Window x:Class="d2mSoftware.Windows.ServerInfoWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:d2MSoftware="clr-namespace:d2mSoftware"
        xmlns:userControls="clr-namespace:d2mSoftware.User_Controls"
        mc:Ignorable="d" 
        UseLayoutRounding="True" ResizeMode="NoResize"
        Title="ServerInfoWindow" Height="415" Width="300" d:DataContext="{d:DesignData d2MSoftware:ServerInfoVM}">
    <Grid>

        <Grid.Resources>
            <d2MSoftware:CustomBoolToVisibilityConverter x:Key="CustomBooleanToVisibilityConverter" />
        </Grid.Resources>

        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="5" />
            <ColumnDefinition />
            <ColumnDefinition Width="5" />
        </Grid.ColumnDefinitions>

        <Grid.RowDefinitions>
            <RowDefinition Height="5" />
            <RowDefinition Height="120" />
            <RowDefinition Height="10" />
            <RowDefinition Height="200" />
            <RowDefinition Height="40" />
            <RowDefinition Height="5" />
        </Grid.RowDefinitions>

        <GroupBox Grid.Column="1" Grid.Row="1" BorderThickness="1" BorderBrush="LightGray">

            <GroupBox.Header>
                <TextBlock FontWeight="Bold" Text="Server Information" />
            </GroupBox.Header>

            <Grid>

                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="65" />
                    <ColumnDefinition />
                    <ColumnDefinition Width="20" />
                </Grid.ColumnDefinitions>

                <Grid.RowDefinitions>
                    <RowDefinition Height="5" />
                    <RowDefinition Height="30" />
                    <RowDefinition Height="30" />
                    <RowDefinition Height="30" />
                </Grid.RowDefinitions>

                <d2MSoftware:ErrorProvider Grid.Row="0" Grid.Column="0" x:Name="ServerValidator" />

                <Label Grid.Row="1" VerticalAlignment="Center" Content="Name:" />

                <TextBox Grid.Row="1" Grid.Column="1" Style="{StaticResource ErrorCheckTextBox}" Text="{Binding ServerName}" TabIndex="0" Height="25" VerticalContentAlignment="Center" Name="TxtServerName" />

                <Label Grid.Row="2" Grid.Column="0" VerticalAlignment="Center" Content="Server:" />

                <TextBox Style="{StaticResource ErrorCheckTextBox}" Grid.Row="2" Grid.Column="1" Text="{Binding ServerAddress}" TabIndex="1" Height="25" VerticalAlignment="Center" VerticalContentAlignment="Center" Name="TxtServerAddress" />

                <Label Grid.Row="3" Grid.Column="0" Content="Port:" VerticalAlignment="Center" />

                <TextBox Grid.Row="3" Grid.Column="1" Style="{StaticResource ErrorCheckTextBox}" Text="{Binding ServerPort}" TabIndex="2" HorizontalAlignment="Left" Height="25" Width="40" VerticalAlignment="Center" VerticalContentAlignment="Center" Name="TxtServerPort" />

                <Button BorderBrush="#74C2E1" Background="LightBlue" Style="{DynamicResource RoundedButton}" TabIndex="3" Grid.Row="3" Grid.Column="1" Name="BtnTestServer" Width="75" HorizontalAlignment="Right" Content="Test" Height="25" Click="BtnTestServer_Click" />

                <userControls:AjaxSpinnerControl Margin="0,0,2,0" Grid.Row="3" Grid.Column="2" x:Name="ServerTestSpinner" Visibility="Hidden" HorizontalAlignment="Right" />

                <TextBlock Name="TxtServerTestResult" Grid.Row="3" Grid.Column="2" HorizontalAlignment="Center" FontFamily="/Resources/#FontAwesome" VerticalAlignment="Center" />

            </Grid>

        </GroupBox>


        <GroupBox Grid.Row="3" Grid.Column="1">

            <GroupBox.Header>
                <TextBlock FontWeight="Bold" Text="Account Information" />
            </GroupBox.Header>

            <Grid>

                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="65" />
                    <ColumnDefinition />
                </Grid.ColumnDefinitions>

                <Grid.RowDefinitions>
                    <RowDefinition Height="5" />
                    <RowDefinition Height="30" />
                    <RowDefinition Height="30" />
                    <RowDefinition Height="5" />
                    <RowDefinition Height="44" />
                    <RowDefinition Height="22" />
                    <RowDefinition Height="22" />
                    <RowDefinition Height="22" />
                </Grid.RowDefinitions>

                <d2MSoftware:ErrorProvider Grid.Row="0" Grid.Column="0" x:Name="CredentialsValidator" />

                <Label Grid.Row="1" Grid.Column="0" VerticalAlignment="Center" Content="Username:" />

                <TextBox Grid.Row="1" Grid.Column="1" Style="{StaticResource ErrorCheckTextBox}" Text="{Binding Username}" Width="177" TabIndex="4" Height="25" HorizontalAlignment="Left" VerticalContentAlignment="Center" Name="TxtUsername" />

                <Label Grid.Row="2" Grid.Column="0" VerticalAlignment="Center" Content="Password:" />

                <PasswordBox Grid.Row="2" Grid.Column="1" Width="177" HorizontalAlignment="Left" TabIndex="5" Height="25" VerticalContentAlignment="Center" Name="TxtPassword" />

                <Grid Grid.Row="4" Grid.Column="0" Grid.ColumnSpan="2" Width="255">

                    <Grid.RowDefinitions>
                        <RowDefinition />
                        <RowDefinition />
                    </Grid.RowDefinitions>

                    <Grid.ColumnDefinitions>
                        <ColumnDefinition />
                        <ColumnDefinition Width="20" />
                    </Grid.ColumnDefinitions>

                    <CheckBox Grid.Row="0" Grid.ColumnSpan="2" TabIndex="5" IsChecked="{Binding RememberUsername}" HorizontalAlignment="Left" VerticalAlignment="Center" Content="Remember username"/>
                    <CheckBox Grid.Row="1" Grid.ColumnSpan="2" TabIndex="6" IsChecked="{Binding RememberPassword}" IsEnabled="{Binding AllowRememberPassword}" HorizontalAlignment="Left" VerticalAlignment="Center" Content="Remember password"/>

                    <Button Grid.RowSpan="2" BorderBrush="#74C2E1" Background="LightBlue" Style="{DynamicResource RoundedButton}" TabIndex="6" Name="BtnTestCredentials" Width="75" HorizontalAlignment="Right" Content="Test" Height="25" Click="BtnTestCredentials_OnClick" />
                    <userControls:AjaxSpinnerControl x:Name="CredentialsTestSpinner" Grid.RowSpan="2" Grid.Column="1" Visibility="Hidden" />
                    <TextBlock Name="TxtCredentialsTestResult" Grid.RowSpan="2" Grid.Column="1" HorizontalAlignment="Center" FontFamily="/Resources/#FontAwesome" VerticalAlignment="Center" />

                </Grid>
                

                <Button Grid.Row="5" Grid.ColumnSpan="2" HorizontalAlignment="Center" Style="{StaticResource HyperlinkLikeButton}" Name="BtnForgotPassword" PreviewMouseDown="BtnForgotPassword_OnPreviewMouseDown" Height="23">
                    <TextBlock VerticalAlignment="Center" Text="Forget your Password?" />
                </Button>

                <userControls:AjaxSpinnerControl Grid.Row="5" Grid.Column="1" x:Name="ForgotPasswordSpinner" Visibility="Hidden" HorizontalAlignment="Right" Margin="0,0,25,0"/>

                <Button Grid.Row="6" Grid.ColumnSpan="2" HorizontalAlignment="Center" Style="{StaticResource HyperlinkLikeButton}" Name="BtnForgotKey" PreviewMouseDown="BtnForgotKey_OnPreviewMouseDown" Height="23">
                    <TextBlock VerticalAlignment="Center" Text="Forget your Private Key?" />
                </Button>

                <userControls:AjaxSpinnerControl Grid.Row="6" Grid.Column="1" x:Name="ForgotKeySpinner" Visibility="Hidden" HorizontalAlignment="Right" Margin="0,0,25,0"/>

                <TextBlock Grid.Row="7" Grid.ColumnSpan="2" HorizontalAlignment="Center" VerticalAlignment="Center" Name="TxtForgotResult" />

            </Grid>

        </GroupBox>

        <UniformGrid Columns="3" Grid.Row="4" Grid.Column="1">
            <Button BorderBrush="#74C2E1" Background="LightBlue" Style="{DynamicResource RoundedButton}" Content="Delete" Name="BtnDelete" Click="BtnDelete_OnClick" Width="75" Height="27" Visibility="{Binding AllowDelete, Converter={StaticResource CustomBooleanToVisibilityConverter}}" />
            <Button BorderBrush="#74C2E1" Background="LightBlue" Style="{DynamicResource RoundedButton}" Name="BtnCancel" Click="BtnCancel_OnClick" TabIndex="8" Width="75" Height="27" Content="Cancel" />
            <Button BorderBrush="#74C2E1" Background="LightBlue" Style="{DynamicResource RoundedButton}" Name="BtnSave" Click="BtnSave_OnClick" TabIndex="7" Width="75" Height="27" Content="Save" />
        </UniformGrid>

    </Grid>
</Window>