namespace HelixToolkit
{
    using System.Windows.Markup;
    using System.Windows.Media;

    /// <summary>
    /// Markupextension for LinearGradientBrush
    /// Usage: Background={helix:LinearGradientBrush Black,White}
    /// </summary>
    public class LinearGradientBrushExtension : MarkupExtension
    {

        private readonly LinearGradientBrush brush;

        /// <summary>
        /// Initializes a new instance of the <see cref="LinearGradientBrushExtension"/> class.
        /// </summary>
        /// <param name="startColor">The start color.</param>
        /// <param name="endColor">The end color.</param>
        /// <param name="angle">The angle.</param>
        public LinearGradientBrushExtension(Color startColor, Color endColor, double angle)
        {
            brush=new LinearGradientBrush(startColor,endColor,angle);
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="LinearGradientBrushExtension"/> class.
        /// </summary>
        /// <param name="startColor">The start color.</param>
        /// <param name="endColor">The end color.</param>
        public LinearGradientBrushExtension(Color startColor, Color endColor)
            : this(startColor, endColor, 90)
        {
        }

        /// <summary>
        /// Returns the linear gradient brush.
        /// </summary>
        /// <param name="serviceProvider">Object that can provide services for the markup extension.</param>
        /// <returns>
        /// The brush to set on the property where the extension is applied.
        /// </returns>
        public override object ProvideValue(System.IServiceProvider serviceProvider)
        {
            return brush;
        }
    }
}