using System.Windows;
using System.Windows.Controls;

namespace Developpez.Dotnet.Windows.Behaviors
{
    /// <summary>
    /// Fournit des propriétés attachées pour ajouter des fonctionnalités aux contrôles PasswordBox
    /// </summary>
    public static class PasswordBoxBehavior
    {
        /// <summary>
        /// Obtient la valeur de la propriété attachée BindPassword
        /// </summary>
        /// <param name="obj">L'objet pour lequel on veut obtenir la valeur</param>
        /// <returns>true si le binding du mot de passe est activé, sinon false</returns>
        [AttachedPropertyBrowsableForType(typeof(PasswordBox))]
        public static bool GetBindPassword(PasswordBox obj)
        {
            return (bool)obj.GetValue(BindPasswordProperty);
        }

        /// <summary>
        /// Définit la valeur de la propriété attachée BindPassword
        /// </summary>
        /// <param name="obj">L'objet pour lequel on veut définir la valeur</param>
        /// <param name="value">true pour activer le binding du mot de passe, sinon false</param>
        public static void SetBindPassword(PasswordBox obj, bool value)
        {
            obj.SetValue(BindPasswordProperty, value);
        }

        /// <summary>
        /// Identifiant de la propriété attachée BindPassword
        /// </summary>
        public static readonly DependencyProperty BindPasswordProperty =
            DependencyProperty.RegisterAttached(
              "BindPassword",
              typeof(bool),
              typeof(PasswordBoxBehavior),
              new UIPropertyMetadata(
                false,
                BindPasswordChanged));

        private static void BindPasswordChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
        {
            var pb = o as PasswordBox;
            if (pb == null)
                return;
            var oldValue = (bool)e.OldValue;
            var newValue = (bool)e.NewValue;
            if (oldValue && !newValue)
            {
                pb.PasswordChanged -= PasswordBoxPasswordChanged;
            }
            else if (newValue && !oldValue)
            {
                SetPassword(pb, pb.Password);
                pb.PasswordChanged += PasswordBoxPasswordChanged;
            }
        }

        /// <summary>
        /// Obtient la valeur de la propriété attachée Password
        /// </summary>
        /// <param name="obj">L'objet pour lequel on veut obtenir la valeur</param>
        /// <returns>Le mot de passe de cette PasswordBox</returns>
        [AttachedPropertyBrowsableForType(typeof(PasswordBox))]
        public static string GetPassword(PasswordBox obj)
        {
            return (string)obj.GetValue(PasswordProperty);
        }

        /// <summary>
        /// Définit la valeur de la propriété attachée Password
        /// </summary>
        /// <param name="obj">L'objet pour lequel on veut définir la valeur</param>
        /// <param name="value">Le nouveau mot de passe pour cette PasswordBox</param>
        public static void SetPassword(PasswordBox obj, string value)
        {
            obj.SetValue(PasswordProperty, value);
        }

        /// <summary>
        /// Identifiant de la propriété attachée Password
        /// </summary>
        public static readonly DependencyProperty PasswordProperty =
            DependencyProperty.RegisterAttached(
              "Password",
              typeof(string),
              typeof(PasswordBoxBehavior),
              new FrameworkPropertyMetadata(
                null,
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault,
                PasswordChanged));

        private static void PasswordChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
        {
            var pb = o as PasswordBox;
            if (pb == null)
                return;

            var newValue = (string)e.NewValue;

            if (GetBindPassword(pb) && pb.Password != newValue)
                pb.Password = newValue;
        }

        static void PasswordBoxPasswordChanged(object sender, RoutedEventArgs e)
        {
            var pb = sender as PasswordBox;
            if (pb == null)
                return;
            SetPassword(pb, pb.Password);
        }
    }
}