/** DGui project file.

Copyright: Trogu Antonio Davide 2011-2013

License: $(HTTP boost.org/LICENSE_1_0.txt, Boost License 1.0).

Authors: Trogu Antonio Davide
*/
module dgui.core.controls.ownerdrawcontrol;

public import dgui.core.controls.subclassedcontrol;
public import dgui.core.events.eventargs;

enum OwnerDrawMode: ubyte
{
	normal = 0,
	fixed = 1,
	variable = 2,
}

enum DrawItemState: uint
{
	default_  = ODS_DEFAULT,
	checked  = ODS_CHECKED,
	disabled = ODS_DISABLED,
	focused  = ODS_FOCUS,
	grayed   = ODS_GRAYED,
	selected = ODS_SELECTED,
}

class MeasureItemEventArgs: EventArgs
{
	private int _width;
	private int _height;
	private int _index;
	private Canvas _canvas;

	public this(Canvas c, int width, int height, int index)
	{
		this._canvas = c;
		this._width = width;
		this._height = height;
		this._index = index;
	}

	@property public Canvas canvas()
	{
		return this._canvas;
	}

	@property public int width()
	{
		return this._width;
	}

	@property public void width(int w)
	{
		this._width = w;
	}

	@property public int height()
	{
		return this._height;
	}

	@property public void height(int h)
	{
		this._height = h;
	}

	@property public int index()
	{
		return this._index;
	}
}

class DrawItemEventArgs: EventArgs
{
	private DrawItemState _state;
	private Color _foreColor;
	private Color _backColor;
	private Canvas _canvas;
	private Rect _itemRect;
	private int _index;

	public this(Canvas c, DrawItemState state, Rect itemRect, Color foreColor, Color backColor, int index)
	{
		this._canvas = c;
		this._state = state;
		this._itemRect = itemRect;
		this._foreColor = foreColor;
		this._backColor = backColor;
		this._index = index;
	}

	@property public Canvas canvas()
	{
		return this._canvas;
	}

	@property public DrawItemState itemState()
	{
		return this._state;
	}

	@property public Rect itemRect()
	{
		return this._itemRect;
	}

	@property public Color foreColor()
	{
		return this._foreColor;
	}

	@property public Color backColor()
	{
		return this._backColor;
	}

	public void drawBackground()
	{
		scope SolidBrush brush = new SolidBrush(this._backColor);
		this._canvas.fillRectangle(brush, this._itemRect);
	}

	public void drawFocusRect()
	{
		if(this._state & DrawItemState.focused)
		{
			DrawFocusRect(this._canvas.handle, &this._itemRect.rect);
		}
	}

	@property public int index()
	{
		return this._index;
	}
}

abstract class OwnerDrawControl: SubclassedControl
{
	public Event!(Control, MeasureItemEventArgs) measureItem;
	public Event!(Control, DrawItemEventArgs) drawItem;

	protected OwnerDrawMode _drawMode = OwnerDrawMode.normal;

	@property public OwnerDrawMode drawMode()
	{
		return this._drawMode;
	}

	@property public void drawMode(OwnerDrawMode dm)
	{
		this._drawMode = dm;
	}

	protected void onMeasureItem(MeasureItemEventArgs e)
	{
		this.measureItem(this, e);
	}

	protected void onDrawItem(DrawItemEventArgs e)
	{
		this.drawItem(this, e);
	}

	protected override void onReflectedMessage(ref Message m)
	{
		switch(m.msg)
		{
			case WM_MEASUREITEM:
			{
				MEASUREITEMSTRUCT* pMeasureItem = cast(MEASUREITEMSTRUCT*)m.lParam;
				HDC hdc = GetDC(this._handle);
				SetBkColor(hdc, this.backColor.colorref);
				SetTextColor(hdc, this.foreColor.colorref);

				scope Canvas c = Canvas.fromHDC(hdc);
				scope MeasureItemEventArgs e = new MeasureItemEventArgs(c, pMeasureItem.itemWidth, pMeasureItem.itemHeight,
																		   pMeasureItem.itemID);

				this.onMeasureItem(e);

				if(e.width)
				{
					pMeasureItem.itemWidth = e.width;
				}

				if(e.height)
				{
					pMeasureItem.itemHeight = e.height;
				}

				ReleaseDC(this._handle, null);
			}
			break;

			case WM_DRAWITEM:
			{
				DRAWITEMSTRUCT* pDrawItem = cast(DRAWITEMSTRUCT*)m.lParam;
				Rect r = Rect.fromRECT(&pDrawItem.rcItem);

				Color fc, bc;

				if(pDrawItem.itemState & ODS_SELECTED)
				{
					fc = SystemColors.colorHighlightText;
					bc = SystemColors.colorHighlight;
				}
				else
				{
					fc = this.foreColor;
					bc = this.backColor;
				}

				scope Canvas c = Canvas.fromHDC(pDrawItem.hDC);
				scope DrawItemEventArgs e = new DrawItemEventArgs(c, cast(DrawItemState)pDrawItem.itemState,
																  r, fc, bc, pDrawItem.itemID);

				this.onDrawItem(e);
			}
			break;

			default:
				break;
		}

		super.onReflectedMessage(m);
	}
}