/* $Id$ */

/** @file window.h regroups declarations for all windowing system, as well as a few helper functions */

#ifndef WINDOW_H
#define WINDOW_H

#include "macros.h"
#include "string.h"
#include "order.h"
#include "rail.h"
#include "road.h"
#include "airport.h"
#include "vehicle.h"

struct WindowEvent;

typedef void WindowProc(Window *w, WindowEvent *e);

/* 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 ResizeFlag {
	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
};

enum {
	WIDGET_LIST_END = -1, ///< indicate the end of widgets' list for vararg functions
};

struct Widget {
	byte type;                        ///< Widget type, see WindowWidgetTypes
	byte display_flags;               ///< Resize direction, alignment, etc. during resizing, see ResizeFlags
	byte color;                       ///< Widget colour, see docs/ottd-colourtext-palette.png
	int16 left, right, top, bottom;   ///< The position offsets inside the window
	uint16 data;                      ///< The String/Image or special code (list-matrixes) of a widget
	StringID tooltips;                ///< Tooltips that are shown when rightclicking on a widget
};

enum FrameFlags {
	FR_NONE         = 0x00,
	FR_TRANSPARENT  = 0x01,  ///< Makes the background transparent if set
	FR_BORDERONLY   = 0x10,  ///< Draw border only, no background
	FR_LOWERED      = 0x20,  ///< If set the frame is lowered and the background color brighter (ie. buttons when pressed)
	FR_DARKENED     = 0x40,  ///< If set the background is darker, allows for lowered frames with normal background color when used with FR_LOWERED (ie. dropdown boxes)
};

DECLARE_ENUM_AS_BIT_SET(FrameFlags);

void DrawFrameRect(int left, int top, int right, int bottom, int color, FrameFlags flags);

enum WindowEventCodes {
	WE_CREATE,
	WE_DESTROY,
	WE_PAINT,
	WE_KEYPRESS,
	WE_CLICK,
	WE_RCLICK,
	WE_MOUSEOVER,
	WE_MOUSELOOP,
	WE_MOUSEWHEEL,
	WE_TICK,
	WE_4,
	WE_TIMEOUT,
	WE_PLACE_OBJ,
	WE_ABORT_PLACE_OBJ,
	WE_ON_EDIT_TEXT,
	WE_ON_EDIT_TEXT_CANCEL,
	WE_POPUPMENU_SELECT,
	WE_POPUPMENU_OVER,
	WE_DRAGDROP,
	WE_PLACE_DRAG,
	WE_PLACE_MOUSEUP,
	WE_PLACE_PRESIZE,
	WE_DROPDOWN_SELECT,
	WE_RESIZE,
	WE_MESSAGE,
	WE_SCROLL,
	WE_INVALIDATE_DATA,
};

struct WindowEvent {
	byte event;
	union {
		struct{
			Point pt;
			int widget;
		} click;

		struct {
			Point pt;
			TileIndex tile;
			TileIndex starttile;
			byte select_method;
			byte select_proc;
		} place;

		struct {
			Point pt;
			int widget;
		} dragdrop;

		struct {
			Point size;
			Point diff;
		} sizing;

		struct {
			char *str;
		} edittext;

		struct {
			Point pt;
		} popupmenu;

		struct {
			int button;
			int index;
		} dropdown;

		struct {
			Point pt;
			int widget;
		} mouseover;

		struct {
			bool cont;      ///< continue the search? (default true)
			uint16 key;     ///< 16-bit Unicode value of the key
			uint16 keycode; ///< untranslated key (including shift-state)
		} keypress;

		struct {
			int msg;      ///< message to be sent
			int wparam;   ///< additional message-specific information
			int lparam;   ///< additional message-specific information
		} message;

		struct {
			Point delta;   ///< delta position against position of last call
		} scroll;

		struct {
			int wheel;     ///< how much was 'wheel'd'
		} wheel;
	} we;
};

struct WindowDesc {
	int16 left, top, width, height;
	WindowClass cls;
	WindowClass parent_cls;
	uint32 flags;
	const Widget *widgets;
	WindowProc *proc;
};

enum WindowDefaultFlag {
	WDF_STD_TOOLTIPS    =   1, ///< use standard routine when displaying tooltips
	WDF_DEF_WIDGET      =   2, ///< default widget control for some widgets in the on click event
	WDF_STD_BTN         =   4, ///< default handling for close and drag widgets (widget no 0 and 1)

	WDF_UNCLICK_BUTTONS =  16, ///< Unclick buttons when the window event times out */
	WDF_STICKY_BUTTON   =  32, ///< Set window to sticky mode; they are not closed unless closed with 'X' (widget 2)
	WDF_RESIZABLE       =  64, ///< A window can be resized
	WDF_MODAL           = 128, ///< The window is a modal child of some other window, meaning the parent is 'inactive'
};

/* can be used as x or y coordinates to cause a specific placement */
enum WindowDefaultPosition {
	WDP_AUTO      = -1, ///< Find a place automatically
	WDP_CENTER    = -2, ///< Center the window (left/right or top/bottom)
	WDP_ALIGN_TBR = -3, ///< Align the right side of the window with the right side of the main toolbar
	WDP_ALIGN_TBL = -4, ///< Align the left side of the window with the left side of the main toolbar
};

struct Textbuf {
	char *buf;                  ///< buffer in which text is saved
	uint16 maxlength, maxwidth; ///< the maximum size of the buffer. Maxwidth specifies screensize in pixels, maxlength is in bytes
	uint16 length, width;       ///< the current size of the string. Width specifies screensize in pixels, length is in bytes
	bool caret;                 ///< is the caret ("_") visible or not
	uint16 caretpos;            ///< the current position of the caret in the buffer, in bytes
	uint16 caretxoffs;          ///< the current position of the caret in pixels
};

#define WP(ptr,str) (*(str*)(ptr)->custom)
/* You cannot 100% reliably calculate the biggest custom struct as
 * the number of pointers in it and alignment will have a huge impact.
 * 96 is the largest window-size for 64-bit machines currently */
#define WINDOW_CUSTOM_SIZE 96

struct Scrollbar {
	uint16 count, cap, pos;
};

struct ResizeInfo {
	uint width; ///< Minimum width and height
	uint height;
	uint step_width; ///< In how big steps the width and height go
	uint step_height;
};

struct WindowMessage {
	int msg;
	int wparam;
	int lparam;
};

struct Window {
	uint16 flags4;
	WindowClass window_class;
	WindowNumber window_number;

	int left, top;
	int width, height;

	Scrollbar hscroll, vscroll, vscroll2;
	ResizeInfo resize;

	byte caption_color;

	WindowProc *wndproc;
	ViewPort *viewport;
	const Widget *original_widget;
	Widget *widget;
	uint widget_count;
	uint32 desc_flags;

	WindowMessage message;
	Window *parent;
	byte custom[WINDOW_CUSTOM_SIZE];
};

struct querystr_d {
	StringID caption;
	Textbuf text;
	const char *orig;
	CharSetFilter afilter;
	bool handled;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(querystr_d));

struct chatquerystr_d : public querystr_d {
	int dest;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(chatquerystr_d));

struct menu_d {
	byte item_count;      ///< follow_vehicle
	byte sel_index;       ///< scrollpos_x
	byte main_button;     ///< scrollpos_y
	byte action_id;
	StringID string_id;   ///< unk30
	uint16 checked_items; ///< unk32
	byte disabled_items;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(menu_d));

struct def_d {
	int16 data_1, data_2, data_3;
	int16 data_4, data_5;
	bool close;
	byte byte_1;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(def_d));

struct void_d {
	void *data;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(void_d));

struct tree_d {
	uint16 base;
	uint16 count;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(tree_d));

struct tooltips_d {
	StringID string_id;
	byte paramcount;
	uint32 params[5];
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(tooltips_d));

struct buildvehicle_d {
	VehicleType vehicle_type;
	union {
		RailTypeByte railtype;
		AirportFTAClass::Flags flags;
		RoadTypes roadtypes;
	} filter;
	byte sel_index;  ///< deprecated value, used for 'unified' ship and road
	bool descending_sort_order;
	byte sort_criteria;
	bool regenerate_list;
	EngineID sel_engine;
	EngineID rename_engine;
	EngineList eng_list;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(buildvehicle_d));

struct replaceveh_d {
	byte sel_index[2];
	EngineID sel_engine[2];
	uint16 count[2];
	bool wagon_btnstate; ///< true means engine is selected
	EngineList list[2];
	bool update_left;
	bool update_right;
	bool init_lists;
	GroupID sel_group;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(replaceveh_d));

struct depot_d {
	VehicleID sel;
	VehicleType type;
	bool generate_list;
	uint16 engine_list_length;
	uint16 wagon_list_length;
	uint16 engine_count;
	uint16 wagon_count;
	Vehicle **vehicle_list;
	Vehicle **wagon_list;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(depot_d));

struct order_d {
	int sel;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(order_d));

struct traindetails_d {
	byte tab;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(traindetails_d));

struct smallmap_d {
	int32 scroll_x;
	int32 scroll_y;
	int32 subscroll;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(smallmap_d));

struct facesel_d {
	uint32 face;
	byte gender;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(facesel_d));

struct refit_d {
	int sel;
	struct RefitOption *cargo;
	struct RefitList *list;
	uint length;
	VehicleOrderID order;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(refit_d));

struct vp_d {
	VehicleID follow_vehicle;
	int32 scrollpos_x;
	int32 scrollpos_y;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(vp_d));

/* vp2_d is the same as vp_d, except for the data_# values.. */
struct vp2_d {
	VehicleID follow_vehicle;
	int32 scrollpos_x;
	int32 scrollpos_y;
	byte data_1;
	byte data_2;
	byte data_3;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(vp2_d));

struct news_d {
	uint16 follow_vehicle;
	int32 scrollpos_x;
	int32 scrollpos_y;
	NewsItem *ni;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(news_d));

struct highscore_d {
	uint32 background_img;
	int8 rank;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(highscore_d));

struct scroller_d {
	int height;
	uint16 counter;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(scroller_d));

enum SortListFlags {
	VL_NONE    = 0x00,  ///< no sort
	VL_DESC    = 0x01,  ///< sort descending or ascending
	VL_RESORT  = 0x02,  ///< instruct the code to resort the list in the next loop
	VL_REBUILD = 0x04,  ///< create sort-listing to use for qsort and friends
	VL_END     = 0x08
};

DECLARE_ENUM_AS_BIT_SET(SortListFlags);

struct Listing {
	bool order;    ///< Ascending/descending
	byte criteria; ///< Sorting criteria
};

struct list_d {
	uint16 list_length;  ///< length of the list being sorted
	byte sort_type;      ///< what criteria to sort on
	SortListFlags flags; ///< used to control sorting/resorting/etc.
	uint16 resort_timer; ///< resort list after a given amount of ticks if set
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(list_d));

struct message_d {
	int msg;
	int wparam;
	int lparam;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(message_d));

struct dropdown_d {
	uint32 disabled_state;
	uint32 hidden_state;
	WindowClass parent_wnd_class;
	WindowNumber parent_wnd_num;
	byte parent_button;
	byte num_items;
	byte selected_index;
	const StringID *items;
	byte click_delay;
	bool drag_mode;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(dropdown_d));

struct vehiclelist_d {
	const Vehicle** sort_list;  // List of vehicles (sorted)
	Listing *_sorting;          // pointer to the appropiate subcategory of _sorting
	uint16 length_of_sort_list; // Keeps track of how many vehicle pointers sort list got space for
	VehicleType vehicle_type;   // The vehicle type that is sorted
	list_d l;                   // General list struct
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(vehiclelist_d));

struct grouplist_d {
	const Group **sort_list;
	list_d l;                   // General list struct
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(grouplist_d));

struct groupveh_d : vehiclelist_d {
	GroupID group_sel;
	VehicleID vehicle_sel;

	grouplist_d gl;
};
assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(groupveh_d));

/****************** THESE ARE NOT WIDGET TYPES!!!!! *******************/
enum WindowWidgetBehaviours {
	WWB_PUSHBUTTON  = 1 << 5,

	WWB_MASK        = 0xE0,
};


enum WindowWidgetTypes {
	WWT_EMPTY,

	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,
	WWT_SCROLLBAR,
	WWT_FRAME,      ///< frame
	WWT_CAPTION,

	WWT_HSCROLLBAR,
	WWT_STICKYBOX,
	WWT_SCROLL2BAR, ///< 2nd vertical scrollbar
	WWT_RESIZEBOX,
	WWT_CLOSEBOX,
	WWT_LAST,       ///< Last Item. use WIDGETS_END to fill up padding!!

	WWT_MASK = 0x1F,

	WWT_PUSHBTN     = WWT_PANEL   | WWB_PUSHBUTTON,
	WWT_PUSHTXTBTN  = WWT_TEXTBTN | WWB_PUSHBUTTON,
	WWT_PUSHIMGBTN  = WWT_IMGBTN  | WWB_PUSHBUTTON,
};

#define WIDGETS_END WWT_LAST,   RESIZE_NONE,     0,     0,     0,     0,     0, 0, STR_NULL

enum WindowFlags {
	WF_TIMEOUT_SHL       = 0,
	WF_TIMEOUT_MASK      = 7,
	WF_DRAGGING          = 1 <<  3,
	WF_SCROLL_UP         = 1 <<  4,
	WF_SCROLL_DOWN       = 1 <<  5,
	WF_SCROLL_MIDDLE     = 1 <<  6,
	WF_HSCROLL           = 1 <<  7,
	WF_SIZING            = 1 <<  8,
	WF_STICKY            = 1 <<  9,

	WF_DISABLE_VP_SCROLL = 1 << 10,

	WF_WHITE_BORDER_ONE  = 1 << 11,
	WF_WHITE_BORDER_MASK = 1 << 12 | WF_WHITE_BORDER_ONE,
	WF_SCROLL2           = 1 << 13,
};

/* window.cpp */
void CallWindowEventNP(Window *w, int event);
void CallWindowTickEvent();
void SetWindowDirty(const Window *w);
void SendWindowMessage(WindowClass wnd_class, WindowNumber wnd_num, int msg, int wparam, int lparam);
void SendWindowMessageClass(WindowClass wnd_class, int msg, int wparam, int lparam);

Window *FindWindowById(WindowClass cls, WindowNumber number);
void DeleteWindow(Window *w);
void DeletePlayerWindows(PlayerID pi);
void ChangeWindowOwner(PlayerID old_player, PlayerID new_player);
Window *BringWindowToFrontById(WindowClass cls, WindowNumber number);
Window *FindWindowFromPt(int x, int y);

bool IsWindowOfPrototype(const Window *w, const Widget *widget);
void AssignWidgetToWindow(Window *w, const Widget *widget);
Window *AllocateWindow(
							int x,
							int y,
							int width,
							int height,
							WindowProc *proc,
							WindowClass cls,
							const Widget *widget);

Window *AllocateWindowDesc(const WindowDesc *desc);
Window *AllocateWindowDescFront(const WindowDesc *desc, int window_number);

void DrawWindowViewport(const Window *w);
void ResizeWindow(Window *w, int x, int y);

/**
 * Sets the enabled/disabled status of a widget.
 * By default, widgets are enabled.
 * On certain conditions, they have to be disabled.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 * @param disab_stat : status to use ie: disabled = true, enabled = false
 */
static inline void SetWindowWidgetDisabledState(Window *w, byte widget_index, bool disab_stat)
{
	assert(widget_index < w->widget_count);
	SB(w->widget[widget_index].display_flags, WIDG_DISABLED, 1, !!disab_stat);
}

/**
 * Sets a widget to disabled.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void DisableWindowWidget(Window *w, byte widget_index)
{
	SetWindowWidgetDisabledState(w, widget_index, true);
}

/**
 * Sets a widget to Enabled.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void EnableWindowWidget(Window *w, byte widget_index)
{
	SetWindowWidgetDisabledState(w, widget_index, false);
}

/**
 * Gets the enabled/disabled status of a widget.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 * @return status of the widget ie: disabled = true, enabled = false
 */
static inline bool IsWindowWidgetDisabled(const Window *w, byte widget_index)
{
	assert(widget_index < w->widget_count);
	return HASBIT(w->widget[widget_index].display_flags, WIDG_DISABLED);
}

/**
 * Sets the hidden/shown status of a widget.
 * By default, widgets are visible.
 * On certain conditions, they have to be hidden.
 * @param w Window on which the widget is located
 * @param widget_index index of this widget in the window
 * @param hidden_stat status to use ie. hidden = true, visible = false
 */
static inline void SetWindowWidgetHiddenState(Window *w, byte widget_index, bool hidden_stat)
{
	assert(widget_index < w->widget_count);
	SB(w->widget[widget_index].display_flags, WIDG_HIDDEN, 1, !!hidden_stat);
}

/**
 * Sets a widget hidden.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void HideWindowWidget(Window *w, byte widget_index)
{
	SetWindowWidgetHiddenState(w, widget_index, true);
}

/**
 * Sets a widget visible.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void ShowWindowWidget(Window *w, byte widget_index)
{
	SetWindowWidgetHiddenState(w, widget_index, false);
}

/**
 * Gets the visibility of a widget.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 * @return status of the widget ie: hidden = true, visible = false
 */
static inline bool IsWindowWidgetHidden(const Window *w, byte widget_index)
{
	assert(widget_index < w->widget_count);
	return HASBIT(w->widget[widget_index].display_flags, WIDG_HIDDEN);
}

/**
 * Sets the lowered/raised status of a widget.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 * @param lowered_stat : status to use ie: lowered = true, raised = false
 */
static inline void SetWindowWidgetLoweredState(Window *w, byte widget_index, bool lowered_stat)
{
	assert(widget_index < w->widget_count);
	SB(w->widget[widget_index].display_flags, WIDG_LOWERED, 1, !!lowered_stat);
}

/**
 * Invert the lowered/raised  status of a widget.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void ToggleWidgetLoweredState(Window *w, byte widget_index)
{
	assert(widget_index < w->widget_count);
	TOGGLEBIT(w->widget[widget_index].display_flags, WIDG_LOWERED);
}

/**
 * Marks a widget as lowered.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void LowerWindowWidget(Window *w, byte widget_index)
{
	SetWindowWidgetLoweredState(w, widget_index, true);
}

/**
 * Marks a widget as raised.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 */
static inline void RaiseWindowWidget(Window *w, byte widget_index)
{
	SetWindowWidgetLoweredState(w, widget_index, false);
}

/**
 * Gets the lowered state of a widget.
 * @param w : Window on which the widget is located
 * @param widget_index : index of this widget in the window
 * @return status of the widget ie: lowered = true, raised= false
 */
static inline bool IsWindowWidgetLowered(const Window *w, byte widget_index)
{
	assert(widget_index < w->widget_count);
	return HASBIT(w->widget[widget_index].display_flags, WIDG_LOWERED);
}

void InitWindowSystem();
void UnInitWindowSystem();
void ResetWindowSystem();
int GetMenuItemIndex(const Window *w, int x, int y);
void InputLoop();
void InvalidateWidget(const Window *w, byte widget_index);
void InvalidateThisWindowData(Window *w);
void InvalidateWindowData(WindowClass cls, WindowNumber number);
void RaiseWindowButtons(Window *w);
void RelocateAllWindows(int neww, int newh);
int PositionMainToolbar(Window *w);
void CDECL SetWindowWidgetsDisabledState(Window *w, bool disab_stat, int widgets, ...);
void CDECL SetWindowWidgetsHiddenState(Window *w, bool hidden_stat, int widgets, ...);
void CDECL SetWindowWidgetsLoweredState(Window *w, bool lowered_stat, int widgets, ...);

/* misc_gui.cpp */
void GuiShowTooltipsWithArgs(StringID str, uint paramcount, const uint params[]);
static inline void GuiShowTooltips(StringID str)
{
	GuiShowTooltipsWithArgs(str, 0, NULL);
}

/* widget.cpp */
int GetWidgetFromPos(const Window *w, int x, int y);
void DrawWindowWidgets(const Window *w);
void ShowDropDownMenu(Window *w, const StringID *strings, int selected, int button, uint32 disabled_mask, uint32 hidden_mask);

void HandleButtonClick(Window *w, byte widget);

Window *GetCallbackWnd();
void DeleteNonVitalWindows();
void DeleteAllNonVitalWindows();
void HideVitalWindows();
void ShowVitalWindows();
Window **FindWindowZPosition(const Window *w);

/* window.cpp */
extern Window *_z_windows[];
extern Window **_last_z_window;
#define FOR_ALL_WINDOWS(wz) for (wz = _z_windows; wz != _last_z_window; wz++)

VARDEF Point _cursorpos_drag_start;

VARDEF int _scrollbar_start_pos;
VARDEF int _scrollbar_size;
VARDEF byte _scroller_click_timeout;

VARDEF bool _scrolling_scrollbar;
VARDEF bool _scrolling_viewport;
VARDEF bool _popup_menu_active;

VARDEF byte _special_mouse_mode;
enum SpecialMouseMode {
	WSM_NONE     = 0,
	WSM_DRAGDROP = 1,
	WSM_SIZING   = 2,
	WSM_PRESIZE  = 3,
};

void ScrollbarClickHandler(Window *w, const Widget *wi, int x, int y);

/** Evenly distribute some widgets when resizing horizontally (often a button row)
 *  The widgets are presumed to be in a line and numberef from left to right (without gaps)
 * @param w widow to modify
 * @param left The leftmost widget to resize
 * @param right The rightmost widget to resize. Since right side of it is used, remember to set it to RESIZE_RIGHT
 */
void ResizeButtons(Window *w, byte left, byte right);

#endif /* WINDOW_H */