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+/* $Id$ */
+
+/** @file widget_type.h Definitions about widgets. */
+
+#ifndef WIDGET_TYPE_H
+#define WIDGET_TYPE_H
+
+#include "core/bitmath_func.hpp"
+#include "strings_type.h"
+#include "gfx_type.h"
+
+/* How the resize system works:
+    First, you need to add a WWT_RESIZEBOX to the widgets, and you need
+     to add the flag WDF_RESIZABLE to the window. Now the window is ready
+     to resize itself.
+    As you may have noticed, all widgets have a RESIZE_XXX in their line.
+     This lines controls how the widgets behave on resize. RESIZE_NONE means
+     it doesn't do anything. Any other option let's one of the borders
+     move with the changed width/height. So if a widget has
+     RESIZE_RIGHT, and the window is made 5 pixels wider by the user,
+     the right of the window will also be made 5 pixels wider.
+    Now, what if you want to clamp a widget to the bottom? Give it the flag
+     RESIZE_TB. This is RESIZE_TOP + RESIZE_BOTTOM. Now if the window gets
+     5 pixels bigger, both the top and bottom gets 5 bigger, so the whole
+     widgets moves downwards without resizing, and appears to be clamped
+     to the bottom. Nice aint it?
+   You should know one more thing about this system. Most windows can't
+    handle an increase of 1 pixel. So there is a step function, which
+    let the windowsize only be changed by X pixels. You configure this
+    after making the window, like this:
+      w->resize.step_height = 10;
+    Now the window will only change in height in steps of 10.
+   You can also give a minimum width and height. The default value is
+    the default height/width of the window itself. You can change this
+    AFTER window - creation, with:
+     w->resize.width or w->resize.height.
+   That was all.. good luck, and enjoy :) -- TrueLight */
+
+enum DisplayFlags {
+	RESIZE_NONE   = 0,  ///< no resize required
+
+	RESIZE_LEFT   = 1,  ///< left resize flag
+	RESIZE_RIGHT  = 2,  ///< rigth resize flag
+	RESIZE_TOP    = 4,  ///< top resize flag
+	RESIZE_BOTTOM = 8,  ///< bottom resize flag
+
+	RESIZE_LR     = RESIZE_LEFT  | RESIZE_RIGHT,   ///<  combination of left and right resize flags
+	RESIZE_RB     = RESIZE_RIGHT | RESIZE_BOTTOM,  ///<  combination of right and bottom resize flags
+	RESIZE_TB     = RESIZE_TOP   | RESIZE_BOTTOM,  ///<  combination of top and bottom resize flags
+	RESIZE_LRB    = RESIZE_LEFT  | RESIZE_RIGHT  | RESIZE_BOTTOM, ///< combination of left, right and bottom resize flags
+	RESIZE_LRTB   = RESIZE_LEFT  | RESIZE_RIGHT  | RESIZE_TOP | RESIZE_BOTTOM,  ///<  combination of all resize flags
+	RESIZE_RTB    = RESIZE_RIGHT | RESIZE_TOP    | RESIZE_BOTTOM, ///<  combination of right, top and bottom resize flag
+
+	/* The following flags are used by the system to specify what is disabled, hidden, or clicked
+	 * They are used in the same place as the above RESIZE_x flags, Widget visual_flags.
+	 * These states are used in exceptions. If nothing is specified, they will indicate
+	 * Enabled, visible or unclicked widgets*/
+	WIDG_DISABLED = 4,  ///< widget is greyed out, not available
+	WIDG_HIDDEN   = 5,  ///< widget is made invisible
+	WIDG_LOWERED  = 6,  ///< widget is paint lowered, a pressed button in fact
+};
+DECLARE_ENUM_AS_BIT_SET(DisplayFlags);
+
+enum {
+	WIDGET_LIST_END = -1, ///< indicate the end of widgets' list for vararg functions
+};
+
+/**
+ * Window widget types
+ */
+enum WidgetType {
+	WWT_EMPTY,      ///< Empty widget, place holder to reserve space in widget array
+
+	WWT_PANEL,      ///< Simple depressed panel
+	WWT_INSET,      ///< Pressed (inset) panel, most commonly used as combo box _text_ area
+	WWT_IMGBTN,     ///< Button with image
+	WWT_IMGBTN_2,   ///< Button with diff image when clicked
+
+	WWT_TEXTBTN,    ///< Button with text
+	WWT_TEXTBTN_2,  ///< Button with diff text when clicked
+	WWT_LABEL,      ///< Centered label
+	WWT_TEXT,       ///< Pure simple text
+	WWT_MATRIX,     ///< List of items underneath each other
+	WWT_SCROLLBAR,  ///< Vertical scrollbar
+	WWT_FRAME,      ///< Frame
+	WWT_CAPTION,    ///< Window caption (window title between closebox and stickybox)
+
+	WWT_HSCROLLBAR, ///< Horizontal scrollbar
+	WWT_STICKYBOX,  ///< Sticky box (normally at top-right of a window)
+	WWT_SCROLL2BAR, ///< 2nd vertical scrollbar
+	WWT_RESIZEBOX,  ///< Resize box (normally at bottom-right of a window)
+	WWT_CLOSEBOX,   ///< Close box (at top-left of a window)
+	WWT_DROPDOWN,   ///< Raised drop down list (regular)
+	WWT_DROPDOWNIN, ///< Inset drop down list (used on game options only)
+	WWT_EDITBOX,    ///< a textbox for typing
+	WWT_LAST,       ///< Last Item. use WIDGETS_END to fill up padding!!
+
+	WWT_MASK = 0x1F,
+
+	WWB_PUSHBUTTON  = 1 << 5,
+	WWB_MASK        = 0xE0,
+
+	WWT_PUSHBTN     = WWT_PANEL   | WWB_PUSHBUTTON,
+	WWT_PUSHTXTBTN  = WWT_TEXTBTN | WWB_PUSHBUTTON,
+	WWT_PUSHIMGBTN  = WWT_IMGBTN  | WWB_PUSHBUTTON,
+};
+
+/** Marker for the "end of widgets" in a Window(Desc) widget table. */
+#define WIDGETS_END WWT_LAST, RESIZE_NONE, INVALID_COLOUR, 0, 0, 0, 0, 0, STR_NULL
+
+/**
+ * Window widget data structure
+ */
+struct Widget {
+	WidgetType type;                  ///< Widget type
+	DisplayFlags display_flags;       ///< Resize direction, alignment, etc. during resizing
+	Colours colour;                   ///< Widget colour, see docs/ottd-colourtext-palette.png
+	int16 left;                       ///< The left edge of the widget
+	int16 right;                      ///< The right edge of the widget
+	int16 top;                        ///< The top edge of the widget
+	int16 bottom;                     ///< The bottom edge of the widget
+	uint16 data;                      ///< The String/Image or special code (list-matrixes) of a widget
+	StringID tooltips;                ///< Tooltips that are shown when rightclicking on a widget
+};
+
+#endif /* WIDGET_TYPE_H */