using System.Windows;
using System.Windows.Controls;
namespace TranslatorByMoth
{

  public class TextBoxWithPrompt : TextBox
  {
    private string _textPrompt;
    private bool _isUsingPrompt;
    private TextAlignment _normalTextAlignment = TextAlignment.Left;
    private TextAlignment _promptTextAlignment = TextAlignment.Center;
    private FontStyle _normalFontStyle = FontStyles.Normal;
    private FontStyle _promptFontStyle = FontStyles.Italic;

    private bool IsUsingPrompt
    {
      get { return _isUsingPrompt; }
      set
      {
        _isUsingPrompt = value;
        if (_isUsingPrompt)
        {
          this.FontStyle = this.PromptFontStyle;
          this.TextAlignment = this.PromptTextAlignment;
        }
        else
        {
          this.FontStyle = this.NormalFontStyle;
          this.TextAlignment = this.NormalTextAlignment;
        }
      }
    }

    protected override void OnGotFocus(RoutedEventArgs e)
    {
      if (this.IsUsingPrompt)
      {
        this.IsUsingPrompt = false;
        this.Text = string.Empty;
      }
      base.OnGotFocus(e);
    }
    protected override void OnLostFocus(RoutedEventArgs e)
    {
      if (this.Text.Trim().Length == 0 || this.Text.Trim() == this.TextPrompt)
      {
        this.IsUsingPrompt = true;
        this.Text = this.TextPrompt;
      }
      base.OnLostFocus(e);
    }

    // Set this property and then follow it with a call to the MyText setter
    public string TextPrompt
    {
      get { return _textPrompt; }
      set
      {
        this.IsUsingPrompt = value.Length > 0; // let it throw if null
        _textPrompt = value;
      }
    }

    // Use this externally instead of Text
    public string MyText
    {
      get
      {
        if (this.IsUsingPrompt || this.Text.Trim().Length == 0)
        {
          return string.Empty;
        }
        return this.Text;
      }
      set
      {
        if (value == null)
        {
          value = string.Empty;
        }

        if (this.IsUsingPrompt && (value.Trim().Length > 0 && value != this.TextPrompt))
        {
          this.IsUsingPrompt = false;
        }

        if (value.Trim().Length == 0 && this._textPrompt.Length > 0) //&& !this.Focused 
        {
          this.IsUsingPrompt = true;
          this.Text = this.TextPrompt;
          return;
        }

        this.Text = value;
      }
    }

    // Styles for prompt and normal
    public TextAlignment NormalTextAlignment
    {
      get { return _normalTextAlignment; }
      set
      {
        _normalTextAlignment = value;
        if (!_isUsingPrompt)
          this.TextAlignment = value;
      }
    }
    public TextAlignment PromptTextAlignment
    {
      get { return _promptTextAlignment; }
      set
      {
        _promptTextAlignment = value;
        if (_isUsingPrompt)
          this.TextAlignment = value;
      }
    }
    public FontStyle NormalFontStyle
    {
      get { return _normalFontStyle; }
      set
      {
        _normalFontStyle = value;
        if (!_isUsingPrompt)
          this.FontStyle = value;
      }
    }
    public FontStyle PromptFontStyle
    {
      get { return _promptFontStyle; }
      set
      {
        _promptFontStyle = value;
        if (_isUsingPrompt)
          this.FontStyle = value;
      }
    }
  }
}