#ifndef VUI_H
#define VUI_H

#include <stdarg.h>
#include <stdint.h>

typedef enum {
	KEY_EOF      = 0,
	KEY_BKSP     = 0x08,
	KEY_RET      = 0x0d,
	KEY_ESC      = 0x1b,
	KEY_DEL      = 0x7f,
	KEY_UTF8_MAX = 0x10ffff,

	KEY_LEFT, KEY_RIGHT, KEY_UP, KEY_DOWN,
	KEY_HOME, KEY_END, KEY_PGUP, KEY_PGDN,

	KEY_F1,  KEY_F2,  KEY_F3,  KEY_F4,
	KEY_F5,  KEY_F6,  KEY_F7,  KEY_F8,
	KEY_F9,  KEY_F10, KEY_F11, KEY_F12,

	KEY_SHIFT_BIT = 0x200000,
	KEY_CTRL_BIT  = 0x400000,
	KEY_ALT_BIT   = 0x800000,
	KEY_META_BIT  = 0x1000000,
	KEY_INVALID   = 0x7fffffff,

	KEY_CTRL_MASK = 0xe000000,
	KEY_BASE_MASK = ~KEY_CTRL_MASK,
} VuiKey;

typedef enum {
	FG_BLACK     = 0,
	FG_RED       = 1,
	FG_GREEN     = 2,
	FG_YELLOW    = 3,
	FG_BLUE      = 4,
	FG_MAGENTA   = 5,
	FG_CYAN      = 6,
	FG_WHITE     = 7,

	FG_BBLACK    = FG_BLACK    + 8,
	FG_BRED      = FG_RED      + 8,
	FG_BGREEN    = FG_GREEN    + 8,
	FG_BYELLOW   = FG_YELLOW   + 8,
	FG_BBLUE     = FG_BLUE     + 8,
	FG_BMAGENTA  = FG_MAGENTA  + 8,
	FG_BCYAN     = FG_CYAN     + 8,
	FG_BWHITE    = FG_WHITE    + 8,

	BG_BLACK     = FG_BLACK    << 4,
	BG_RED       = FG_RED      << 4,
	BG_GREEN     = FG_GREEN    << 4,
	BG_YELLOW    = FG_YELLOW   << 4,
	BG_BLUE      = FG_BLUE     << 4,
	BG_MAGENTA   = FG_MAGENTA  << 4,
	BG_CYAN      = FG_CYAN     << 4,
	BG_WHITE     = FG_WHITE    << 4,

	BG_BBLACK    = FG_BBLACK   << 4,
	BG_BRED      = FG_BRED     << 4,
	BG_BGREEN    = FG_BGREEN   << 4,
	BG_BYELLOW   = FG_BYELLOW  << 4,
	BG_BBLUE     = FG_BBLUE    << 4,
	BG_BMAGENTA  = FG_BMAGENTA << 4,
	BG_BCYAN     = FG_BCYAN    << 4,
	BG_BWHITE    = FG_BWHITE   << 4,

	A_BOLD       = 1 << 8,
	A_DIM        = 1 << 9,
	A_ITALIC     = 1 << 10,
	A_UNDERSCORE = 1 << 11,
	A_BLINK      = 1 << 12,
	A_REVERSE    = 1 << 13,
} VuiAttr;

#define ATTR_FG(a) ((a) & 0xf)
#define ATTR_BG(a) (((a)>>4) & 0xf)
#define ATTR_A(a) ((a) & ~0xff)
#define ATTR_DEFAULT (FG_WHITE | BG_BLACK)

typedef uint32_t VuiChar;

typedef struct {
	unsigned width, height;
	VuiChar *chr;
	uint16_t *attr;
} VuiBuffer;

typedef struct {
	unsigned width, height;
	VuiBuffer buf1, buf2;
	VuiBuffer *front, *back;
	void (*redraw_fn)(void *ctx);
	void *redraw_ctx;
	int redraw_all;
	int scroll_x, scroll_y;
	int curs_vis, curs_x, curs_y;
} VuiWindow;

VuiWindow *vui_win(void);

#define LINES (vui_win()->height)
#define COLS  (vui_win()->width)

#define BCHR(b,x,y)  ((b)->chr[(x) + (y) * (b)->width])
#define BATTR(b,x,y) ((b)->attr[(x) + (y) * (b)->width])
#define CHR(x,y)  BCHR(vui_win()->front, x, y)
#define ATTR(x,y) BATTR(vui_win()->front, x, y)

void vui_init(void);
void vui_fini(void);

void vui_blit(void);
void vui_clear(void);
void vui_scroll(int dx, int dy);

void vui_chr(int x, int y, VuiChar c);
void vui_chra(int x, int y, VuiChar c, VuiAttr a);

void vui_puts(int x, int y, const char *s);
void vui_putsa(int x, int y, const char *s, VuiAttr a);
void vui_putsn(int x, int y, const char *s, unsigned n);
void vui_putsna(int x, int y, const char *s, unsigned n, VuiAttr a);

int vui_avprintf(int x, int y, VuiAttr a, const char *fmt, va_list ap);
int vui_aprintf(int x, int y, VuiAttr a, const char *fmt, ...);
int vui_printf(int x, int y, const char *fmt, ...);

void vui_fill(VuiChar c, VuiAttr a);
void vui_fill_rect(VuiChar c, VuiAttr a, int x0, int y0, int width, int height);

void vui_curs_vis(int vis);
void vui_curs_pos(int x, int y);

void vui_redraw_fn(void (*fn)(void *ctx));
void vui_redraw_ctx(void *ctx);

int vui_wait_for_input(int ms);
int vui_has_input(void);
VuiKey vui_key(void);

#endif