using System.ComponentModel;
using System.Drawing;
using System.Windows;
using System.Windows.Forms;
using System.Windows.Media;

namespace CustomControls
{
    [DesignTimeVisible(false)]
    public class OwnerDrawItem : System.Windows.Controls.Control
    {
        public bool IsSelectedChanged
        {
            get { return false; }
            set { SetValue(IsSelectedChangedProperty, value); }
        }
        public readonly static DependencyProperty IsSelectedChangedProperty = DependencyProperty.Register(
            "IsSelectedChanged", typeof(bool), typeof(OwnerDrawItem), new UIPropertyMetadata(false, (o, e) => (o as OwnerDrawItem).InvalidateVisual()));

        public new bool IsEnabledChanged
        {
            get { return false; }
            set { SetValue(IsEnabledChangedProperty, value); }
        }
        public readonly static DependencyProperty IsEnabledChangedProperty = DependencyProperty.Register(
            "IsEnabledChanged", typeof(bool), typeof(OwnerDrawItem), new UIPropertyMetadata(false, (o, e) => (o as OwnerDrawItem).InvalidateVisual()));

        public bool IsMouseOverChanged
        {
            get { return false; }
            set { SetValue(IsMouseOverChangedProperty, value); }
        }
        public readonly static DependencyProperty IsMouseOverChangedProperty = DependencyProperty.Register(
            "IsMouseOverChanged", typeof(bool), typeof(OwnerDrawItem), new UIPropertyMetadata(false, (o, e) => (o as OwnerDrawItem).InvalidateVisual()));

        // this is used to invalidate item when its value changes (case: combobox drawing its value in the cbx part)
        public object Value
        {
            get { return GetValue(ValueProperty); }
            set { SetValue(ValueProperty, value); }
        }
        public readonly static DependencyProperty ValueProperty = DependencyProperty.Register(
            "Value", typeof(object), typeof(OwnerDrawItem), new UIPropertyMetadata(null, (o, e) => (o as OwnerDrawItem).InvalidateVisual()));

        protected void OnDrawItem(DrawingContext drawingContext, int index, bool isSelected, bool isEnabled, bool isMouseOver, bool comboboxEdit, DrawItemEventHandler drawItem) 
        {
            if (ActualWidth == 0 || ActualHeight == 0)
                return;

            var state = DrawItemState.Default;
            if (isSelected)
                state |= DrawItemState.Selected;
            if (!isEnabled)
                state |= DrawItemState.Disabled;
            if (isMouseOver)
                state |= DrawItemState.HotLight;
            if (comboboxEdit)
                state |= DrawItemState.ComboBoxEdit;

            var scale = Helper.GetDpiScale(this);
            using (var bmp = new Bitmap((int)(ActualWidth * scale), (int)(ActualHeight * scale)))
            {
                using (var g = Graphics.FromImage(bmp))
                using (var font = Helper.GetFont(this))
                {
                    var args = new DrawItemEventArgs(g, font, new Rectangle(0, 0, bmp.Width, bmp.Height), index, state);
                    drawItem.Invoke(this, args);
                }

                var imageSource = Helper.GetImage(bmp);
                if (FlowDirection == FlowDirection.RightToLeft)
                    drawingContext.PushTransform(new MatrixTransform(-1, 0, 0, 1, ActualWidth, 0));
                drawingContext.DrawImage(imageSource, new Rect(0, 0, ActualWidth, ActualHeight));
            }
        }
    }
}