#ifndef UI_H
#define UI_H

// these defines and structures are for internal use only
// (ui_t is passed around by users of the system, but should not be altered)
#define MAX_UI_COUNT 16
#define MAX_UI_ITEMS 256

typedef struct
{
	char name[32];
	int flags;
	char *draw_picname;
	char *draw_string;
	int draw_x, draw_y;
	int click_x, click_y, click_x2, click_y2;
	void(*leftkey)(void *nativedata1, void *nativedata2, float data1, float data2);
	void(*rightkey)(void *nativedata1, void *nativedata2, float data1, float data2);
	void(*enterkey)(void *nativedata1, void *nativedata2, float data1, float data2);
	void(*mouseclick)(void *nativedata1, void *nativedata2, float data1, float data2, float xfrac, float yfrac);
	void *nativedata1, *nativedata2;
	float data1, data2;
}
ui_item_t;

typedef struct
{
	int item_count;
	int pad;
	ui_item_t items[MAX_UI_ITEMS];
}
ui_t;

// engine use:
// initializes the ui system
void ui_init(void);
// updates the mouse position, given an absolute loation (some input systems use this)
void ui_mouseupdate(float x, float y);
// updates the mouse position, by an offset from the previous location (some input systems use this)
void ui_mouseupdaterelative(float x, float y);
// left key update
void ui_leftkeyupdate(int pressed);
// right key update
void ui_rightkeyupdate(int pressed);
// up key update
void ui_upkeyupdate(int pressed);
// down key update
void ui_downkeyupdate(int pressed);
// mouse button update (note: 0 = left, 1 = right, 2 = middle, 3+ not supported yet)
void ui_mousebuttonupdate(int button, int pressed);
// perform input updates and check for clicks on items (note: calls callbacks)
void ui_update(void);
// draw all items of all panels
void ui_draw(void);

// intentionally public functions:
// creates a panel
ui_t *ui_create(void);
// frees a panel
void ui_free(ui_t *ui);
// empties a panel, removing all the items
void ui_clear(ui_t *ui);
// sets an item in a panel (adds or replaces the item)
void ui_item
(
	ui_t *ui, char *basename, int number,
	float x, float y, char *picname, char *string,
	float left, float top, float width, float height,
	void(*leftkey)(void *nativedata1, void *nativedata2, float data1, float data2),
	void(*rightkey)(void *nativedata1, void *nativedata2, float data1, float data2),
	void(*enterkey)(void *nativedata1, void *nativedata2, float data1, float data2),
	void(*mouseclick)(void *nativedata1, void *nativedata2, float data1, float data2, float xfrac, float yfrac),
	void *nativedata1, void *nativedata2, float data1, float data2
);
// removes an item from a panel
void ui_item_remove(ui_t *ui, char *basename, int number);
// checks if a panel is enabled
int ui_uiactive(ui_t *ui);
// enables/disables a panel on the screen
void ui_activate(ui_t *ui, int yes);

#endif