/* execute.c -- implements execute.h */
#include "execute.h"

#include <stdlib.h>
#include <unistd.h>

#include "estruct.h"
#include "bind.h"
#include "random.h"
#include "display.h"
#include "file.h"
#include "mlout.h"
#include "search.h"
#include "terminal.h"
#include "window.h"

int gasave = 256 ;		/* global ASAVE size            */
int gacount = 256 ;		/* count until next ASAVE       */


/* insert a # into the text here...we are in CMODE */
static int inspound( int n) {
/* if we are at the beginning of the line, no go */
	if( n == 1 && curwp->w_doto != 0) {
		int i ;

	/* scan to see if all space before this is white space */
		for( i = curwp->w_doto - 1 ; i >= 0 ; i -= 1) {
			int ch ;	/* last character before input */

			ch = lgetc( curwp->w_dotp, i) ;
			if( ch != ' ' && ch != '\t')
				break ;
		}

	/* delete back first */
		if( i < 0)
			while( getccol( FALSE) >= 1)
				backdel( FALSE, 1) ;
	}

/* and insert the required pound */
	return linsert( n, '#') ;
}

/*
 * insert a brace into the text here...we are in CMODE
 *
 * int n;	repeat count
 * int c;	brace to insert (if not }, just normal insertion).
 */
static int insbrace( int n, int c) {
	int ch ;			/* last character before input */
	int oc ;			/* caractere oppose a c */
	int i, count ;
	int target ;		/* column brace should go after */
	struct line *oldlp ;
	int oldoff ;

/* if not called with {, acts as insertion */
	if( c == '}')
		oc = '{' ;
	else
		return linsert( n, c) ;

/* scan to see if all preceding spaces are white spaces, if not, insert */
	for( i = curwp->w_doto - 1 ; i >= 0 ; --i) {
		ch = lgetc( curwp->w_dotp, i) ;
		if( ch != ' ' && ch != '\t')
			return linsert( n, c) ;
	}

	oldlp = curwp->w_dotp ;
	oldoff = curwp->w_doto ;

	count = 1 ;
	do {
		if( boundry( curwp->w_dotp, curwp->w_doto, REVERSE)) {
		/* at beginning of buffer, no match to be found */
			curwp->w_dotp = oldlp ;
			curwp->w_doto = oldoff ;
			return linsert( n, c) ;
		}
		
		backchar( FALSE, 1) ;

		/* if not eol */
		if( curwp->w_doto != llength( curwp->w_dotp)) {
			ch = lgetc( curwp->w_dotp, curwp->w_doto) ;
			if( ch == c)
				++count ;
			else if( ch == oc)
				--count ;
		}
	} while( count > 0) ;

	curwp->w_doto = 0 ;	/* debut de ligne */
	/* aller au debut de la ligne apres la tabulation */
	while( (ch = lgetc( curwp->w_dotp, curwp->w_doto)) == ' '
	       || ch == '\t')
		forwchar( FALSE, 1) ;

	/* delete back first */
	target = getccol( FALSE) ;	/* c'est l'indent que l'on doit avoir */
	curwp->w_dotp = oldlp ;
	curwp->w_doto = oldoff ;

	while( target != getccol( FALSE)) {
		if( target < getccol( FALSE))	/* on doit detruire des caracteres */
			while( getccol( FALSE) > target)
				backdel( FALSE, 1) ;
		else {		/* on doit en inserer */
			while( target - getccol( FALSE) >= tabwidth)
				insert_tab( FALSE, 1) ;

			linsert( target - getccol( FALSE), ' ') ;
		}
	}

	/* and insert the required brace(s) */
	return linsert( n, c) ;
}

#if CFENCE
/*
 * Close fences are matched against their partners, and if
 * on screen the cursor briefly lights there
 *
 * char ch;			fence type to match against
 */
static void fmatch( int ch) {
	struct line *oldlp ;	/* original line pointer */
	int oldoff ;			/* and offset */
	struct line *toplp ;	/* top line in current window */
	int count ;				/* current fence level count */
	int opench ;			/* open fence */

	/* $tpause <= 0 disable fmatch */
	if( term.t_pause <= 0)
		return ;

	/* first get the display update out there */
	update( FALSE) ;

	/* save the original cursor position */
	oldlp = curwp->w_dotp ;
	oldoff = curwp->w_doto ;

	/* setup proper open fence for passed close fence */
	if( ch == ')')
		opench = '(' ;
	else if( ch == '}')
		opench = '{' ;
	else
		opench = '[' ;

	/* find the top line and set up for scan */
	toplp = curwp->w_linep->l_bp ;
	backchar( FALSE, 1) ;	/* . was after the }, move back */

	/* scan back until we find it, or reach past the top of the window */
	count = 1 ;
	do {
		/* At beginning of window or buffer, no match to be found */
		if( curwp->w_dotp == toplp
		||	boundry( curwp->w_dotp, curwp->w_doto, REVERSE))
			break ;

		backchar( FALSE, 1) ;

		/* if not eol */
		if( curwp->w_doto != llength(curwp->w_dotp)) {
			int c ;					/* current character in scan */

			c = lgetc( curwp->w_dotp, curwp->w_doto) ;
			if( c == ch)
				++count ;
			else if( c == opench)
				--count ;
		}
	} while( count > 0) ;

	/* if count is zero, we have a match, display the sucker */
	if( count == 0) {
		int i ;

		/* there is a real machine dependant timing problem here we have
		   yet to solve......... */
		for( i = 0 ; i < term.t_pause ; i++) {
			update( FALSE) ;
			usleep( 10000L) ;
		}
	}

	/* restore the current position */
	curwp->w_dotp = oldlp ;
	curwp->w_doto = oldoff ;
}
#endif


/*
 * This is the general command execution routine. It handles the fake binding
 * of all the keys to "self-insert". It also clears out the "thisflag" word,
 * and arranges to move it to the "lastflag", so that the next command can
 * look at it. Return the status of command.
 */
int execute(int c, int f, int n)
{
	int status;
	fn_t execfunc;

/* if the keystroke is a bound function...do it */
	execfunc = getbind(c);
	if (execfunc != NULL) {
		thisflag = 0;
		status = (*execfunc) (f, n);
		lastflag = thisflag;
		return status;
	}

/* keystroke not bound => self insert, check if buffer is read only */
	if (curbp->b_mode & MDVIEW)
		return rdonly() ;

	/*
	 * If a space was typed, fill column is defined, the argument is non-
	 * negative, wrap mode is enabled, and we are now past fill column,
	 * and we are not read-only, perform word wrap.
	 */
	if (c == ' ' && (curwp->w_bufp->b_mode & MDWRAP) && fillcol > 0 &&
	    n >= 0 && getccol(FALSE) > fillcol &&
	    (curwp->w_bufp->b_mode & MDVIEW) == FALSE)
		execute(META | SPEC | 'W', FALSE, 1);

#if	PKCODE
	if ((c >= 0x20 && c <= 0x7E)	/* Self inserting.      */
#if	IBMPC
	    || (c >= 0x80 && c <= 0xFE)) {
#else
#if	VMS || BSD || USG	/* 8BIT P.K. */
	    || (c >= 0xA0 && c <= 0x10FFFF)) {
#else
	    ) {
#endif
#endif
#else
	if ((c >= 0x20 && c <= 0xFF)) {	/* Self inserting.      */
#endif
		if (n <= 0) {	/* Fenceposts.          */
			lastflag = 0;
			return n < 0 ? FALSE : TRUE;
		}
		thisflag = 0;	/* For the future.      */

		/* if we are in overwrite mode, not at eol,
		   and next char is not a tab or we are at a tab stop,
		   delete a char forword                        */
		if (curwp->w_bufp->b_mode & MDOVER &&
		    curwp->w_doto < curwp->w_dotp->l_used &&
		    (lgetc(curwp->w_dotp, curwp->w_doto) != '\t' ||
		     ((curwp->w_doto) % tabwidth) == (tabwidth - 1)))
			ldelchar(1, FALSE);

		/* do the appropriate insertion */
		switch( c) {
		case '}':
		case ']':
		case ')':
		case '#':
			if( (curbp->b_mode & MDCMOD) != 0) {
				if( c == '#')
					status = inspound( n) ;
				else {
					status = insbrace( n, c) ;
#if	CFENCE
					if( status == TRUE)
						fmatch( c) ;	/* check for CMODE fence matching */
#endif
				}

				break ;
			}
		default:
			status = linsert( n, c) ;
		}

		/* check auto-save mode */
		if (curbp->b_mode & MDASAVE)
			if (--gacount == 0) {
				/* and save the file if needed */
				upscreen(FALSE, 0);
				filesave(FALSE, 0);
				gacount = gasave;
			}

		lastflag = thisflag;
		return status;
	}

	lastflag = 0 ;		/* Fake last flags. */
	mloutfmt( "%B(Key not bound)") ;	/* Complain */
	return FALSE ;
}


/* end of execute.c */