/************************************************************************ 
 * This file is part of PDCurses. PDCurses is public domain software;	*
 * you may use it for any purpose. This software is provided AS IS with	*
 * NO WARRANTY whatsoever.						*
 *									*
 * If you use PDCurses in an application, an acknowledgement would be	*
 * appreciated, but is not mandatory. If you make corrections or	*
 * enhancements to PDCurses, please forward them to the current		*
 * maintainer for the benefit of other users.				*
 *									*
 * See the file maintain.er for details of the current maintainer.	*
 ************************************************************************/

#include <curspriv.h>

RCSID("$Id: getch.c,v 1.68 2007/06/21 06:54:50 wmcbrine Exp $")

/*man-start**************************************************************

  Name:								getch

  Synopsis:
	int getch(void);
	int wgetch(WINDOW *win);
	int mvgetch(int y, int x);
	int mvwgetch(WINDOW *win, int y, int x);
	int ungetch(int ch);
	int flushinp(void);

	int get_wch(wint_t *wch);
	int wget_wch(WINDOW *win, wint_t *wch);
	int mvget_wch(int y, int x, wint_t *wch);
	int mvwget_wch(WINDOW *win, int y, int x, wint_t *wch);
	int unget_wch(const wchar_t wch);

	unsigned long PDC_get_key_modifiers(void);
	int PDC_save_key_modifiers(bool flag);
	int PDC_return_key_modifiers(bool flag);

  Description:
	With the getch(), wgetch(), mvgetch(), and mvwgetch() functions, 
	a character is read from the terminal associated with the window. 
	In nodelay mode, if there is no input waiting, the value ERR is 
	returned. In delay mode, the program will hang until the system 
	passes text through to the program. Depending on the setting of 
	cbreak(), this will be after one character or after the first 
	newline.  Unless noecho() has been set, the character will also 
	be echoed into the designated window.

	If keypad() is TRUE, and a function key is pressed, the token for
	that function key will be returned instead of the raw characters.
	Possible function keys are defined in <curses.h> with integers
	beginning with 0401, whose names begin with KEY_.

	If nodelay(win, TRUE) has been called on the window and no input
	is waiting, the value ERR is returned.

	The ungetch() function places ch back onto the input queue to be
	returned by the next call to wgetch().

	The flushinp() routine throws away any type-ahead that has been
	typed by the user and has not yet been read by the program.

	PDC_get_key_modifiers() returns the keyboard modifiers (shift, 
	control, alt, numlock) effective at the time of the last getch() 
	call, if PDC_save_key_modifiers(TRUE) has been called before the 
	getch(). Use the macros PDC_KEY_MODIFIER_* to determine which 
	modifier(s) were set. PDC_return_key_modifiers() tells getch() 
	to return modifier keys pressed alone as keystrokes (KEY_ALT_L, 
	etc.). These may not work on all platforms.

	NOTE: getch() and ungetch() are implemented as macros, to avoid 
	conflict with many DOS compiler's runtime libraries.

  Return Value:
	These functions return ERR or the value of the character, meta 
	character or function key token.

  Portability				     X/Open    BSD    SYS V
	getch					Y	Y	Y
	wgetch					Y	Y	Y
	mvgetch					Y	Y	Y
	mvwgetch				Y	Y	Y
	ungetch					Y	Y	Y
	flushinp				Y	Y	Y
	get_wch					Y
	wget_wch				Y
	mvget_wch				Y
	mvwget_wch				Y
	unget_wch				Y
	PDC_get_key_modifiers			-	-	-

**man-end****************************************************************/

#define _INBUFSIZ	512	/* size of terminal input buffer */
#define NUNGETCH	256	/* max # chars to ungetch() */

static int c_pindex = 0;	/* putter index */
static int c_gindex = 1;	/* getter index */
static int c_ungind = 0;	/* ungetch() push index */
static int c_ungch[NUNGETCH];	/* array of ungotten chars */

static int _mouse_key(WINDOW *win)
{
	int i, key = KEY_MOUSE;
	unsigned long mbe = SP->_trap_mbe;

	/* Filter unwanted mouse events */

	for (i = 0; i < 3; i++)
	{
		if (pdc_mouse_status.changes & (1 << i))
		{
			int shf = i * 5;
			short button = pdc_mouse_status.button[i] &
				BUTTON_ACTION_MASK;

			if (	(!(mbe & (BUTTON1_PRESSED << shf)) &&
				(button == BUTTON_PRESSED))

				|| (!(mbe & (BUTTON1_CLICKED << shf)) &&
				(button == BUTTON_CLICKED))

				|| (!(mbe & (BUTTON1_DOUBLE_CLICKED << shf)) &&
				(button == BUTTON_DOUBLE_CLICKED))

				|| (!(mbe & (BUTTON1_MOVED << shf)) &&
				(button == BUTTON_MOVED))

				|| (!(mbe & (BUTTON1_RELEASED << shf)) &&
				(button == BUTTON_RELEASED))
			)
				pdc_mouse_status.changes ^= (1 << i);
		}
	}

	if (pdc_mouse_status.changes & PDC_MOUSE_MOVED)
	{
		if (!(mbe & (BUTTON1_MOVED|BUTTON2_MOVED|BUTTON3_MOVED)))
			pdc_mouse_status.changes ^= PDC_MOUSE_MOVED;
	}

	if (pdc_mouse_status.changes &
		(PDC_MOUSE_WHEEL_UP|PDC_MOUSE_WHEEL_DOWN))
	{
		if (!(mbe & MOUSE_WHEEL_SCROLL))
			pdc_mouse_status.changes &=
				~(PDC_MOUSE_WHEEL_UP|PDC_MOUSE_WHEEL_DOWN);
	}

	if (!pdc_mouse_status.changes)
		return -1;

	/* Check for click in slk area */

	i = PDC_mouse_in_slk(pdc_mouse_status.y, pdc_mouse_status.x);

	if (i)
	{
		if (pdc_mouse_status.button[0] &
		    (BUTTON_PRESSED|BUTTON_CLICKED))
			key = KEY_F(i);
		else
			key = -1;
	}

	return key;
}

int wgetch(WINDOW *win)
{
	static int buffer[_INBUFSIZ];	/* character buffer */
	int key, waitcount;

	PDC_LOG(("wgetch() - called\n"));

	if (!win)
		return ERR;

	waitcount = 0;

	 /* set the number of 1/20th second napms() calls */

	if (SP->delaytenths)
		waitcount = 2 * SP->delaytenths;
	else
		if (win->_delayms)
		{
			/* Can't really do millisecond intervals, so 
			   delay in 1/20ths of a second (50ms) */

			waitcount = win->_delayms / 50;
			if (!waitcount)
				waitcount = 1;
		}

	/* refresh window when wgetch is called if there have been 
	   changes to it and it is not a pad */

	if (!(win->_flags & _PAD) && ((!win->_leaveit && (win->_curx !=
	    SP->curscol || win->_cury != SP->cursrow)) || is_wintouched(win)))
		wrefresh(win);

	/* if ungotten char exists, remove and return it */

	if (c_ungind)
		return c_ungch[--c_ungind];

	/* if normal and data in buffer */

	if ((!SP->raw_inp && !SP->cbreak) && (c_gindex < c_pindex))
		return buffer[c_gindex++];

	/* prepare to buffer data */

	c_pindex = 0;
	c_gindex = 0;

	/* to get here, no keys are buffered. go and get one. */

	for (;;)			/* loop for any buffering */
	{
		/* is there a keystroke ready? */

		if (!PDC_check_key())
		{
			/* if not, handle timeout() and halfdelay() */

			if (SP->delaytenths || win->_delayms)
			{
				if (!waitcount)
					return ERR;

				waitcount--;
			}
			else
				if (win->_nodelay)
					return ERR;

			napms(50);	/* sleep for 1/20th second */
			continue;	/* then check again */
		}

		/* if there is, fetch it */

		key = PDC_get_key();

		if (SP->key_code)
		{
			/* filter special keys if not in keypad mode */

			if (!win->_use_keypad)
				key = -1;

			/* filter mouse events; translate mouse clicks 
			   in the slk area to function keys */

			else if (key == KEY_MOUSE)
				key = _mouse_key(win);
		}

		/* unwanted key? loop back */

		if (key == -1)
			continue;

		/* translate CR */

		if (key == '\r' && SP->autocr && !SP->raw_inp)
			key = '\n';

		/* if echo is enabled */

		if (SP->echo && !SP->key_code)
		{
			waddch(win, key);
			wrefresh(win);
		}

		/* if no buffering */

		if (SP->raw_inp || SP->cbreak)
			return key;

		/* if no overflow, put data in buffer */

		if (key == '\b')
		{
			if (c_pindex > c_gindex)
				c_pindex--;
		}
		else
			if (c_pindex < _INBUFSIZ - 2)
				buffer[c_pindex++] = key;

		/* if we got a line */

		if (key == '\n' || key == '\r')
			return buffer[c_gindex++];
	}
}

int mvgetch(int y, int x)
{
	PDC_LOG(("mvgetch() - called\n"));

	if (move(y, x) == ERR)
		return ERR;

	return wgetch(stdscr);
}

int mvwgetch(WINDOW *win, int y, int x)
{
	PDC_LOG(("mvwgetch() - called\n"));

	if (wmove(win, y, x) == ERR)
		return ERR;

	return wgetch(win);
}

int PDC_ungetch(int ch)
{
	PDC_LOG(("ungetch() - called\n"));

	if (c_ungind >= NUNGETCH)	/* pushback stack full */
		return ERR;

	c_ungch[c_ungind++] = ch;

	return OK;
}

int flushinp(void)
{
	PDC_LOG(("flushinp() - called\n"));

	PDC_flushinp();

	c_gindex = 1;			/* set indices to kill buffer */
	c_pindex = 0;
	c_ungind = 0;			/* clear c_ungch array */

	return OK;
}

unsigned long PDC_get_key_modifiers(void)
{
	PDC_LOG(("PDC_get_key_modifiers() - called\n"));

	return pdc_key_modifiers;
}

int PDC_save_key_modifiers(bool flag)
{
	PDC_LOG(("PDC_save_key_modifiers() - called\n"));

	SP->save_key_modifiers = flag;
	return OK;
}

int PDC_return_key_modifiers(bool flag)
{
	PDC_LOG(("PDC_return_key_modifiers() - called\n"));

	SP->return_key_modifiers = flag;
	return PDC_modifiers_set();
}

#ifdef PDC_WIDE
int wget_wch(WINDOW *win, wint_t *wch)
{
	int key;

	PDC_LOG(("wget_wch() - called\n"));

	if (!wch)
		return ERR;

	key = wgetch(win);

	if (key == ERR)
		return ERR;

	*wch = key;

	return SP->key_code ? KEY_CODE_YES : OK;
}

int get_wch(wint_t *wch)
{
	PDC_LOG(("get_wch() - called\n"));

	return wget_wch(stdscr, wch);
}

int mvget_wch(int y, int x, wint_t *wch)
{
	PDC_LOG(("mvget_wch() - called\n"));

	if (move(y, x) == ERR)
		return ERR;

	return wget_wch(stdscr, wch);
}

int mvwget_wch(WINDOW *win, int y, int x, wint_t *wch)
{
	PDC_LOG(("mvwget_wch() - called\n"));

	if (wmove(win, y, x) == ERR)
		return ERR;

	return wget_wch(win, wch);
}

int unget_wch(const wchar_t wch)
{
	return PDC_ungetch(wch);
}
#endif