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

/*	word.c
 *
 *      The routines in this file implement commands that work word or a
 *      paragraph at a time.  There are all sorts of word mode commands.  If I
 *      do any sentence mode commands, they are likely to be put in this file.
 *
 *	Modified by Petri Kutvonen
 */

#include <stdio.h>
#include <stdlib.h>	/* malloc, free */
#include <string.h> /* memcpy */

#include "basic.h"
#include "buffer.h"
#include "estruct.h"
#include "isa.h"
#include "line.h"
#include "mlout.h"
#include "random.h"
#include "region.h"
#include "window.h"

#define ALLOCSZ	32
#define	TAB	0x09		/* a tab character              */

static int justflag = FALSE ;		/* justify, don't fill */

static int inword( void) ;

/* Word wrap on n-spaces. Back-over whatever precedes the point on the current
 * line and stop on the first word-break or the beginning of the line. If we
 * reach the beginning of the line, jump back to the end of the word and start
 * a new line.	Otherwise, break the line at the word-break, eat it, and jump
 * back to the end of the word.
 * Returns TRUE on success, FALSE on errors.
 *
 * @f: default flag.
 * @n: numeric argument.
 */
int wrapword(int f, int n)
{
	int cnt;	/* size of word wrapped to next line */
	int c;		/* charector temporary */

	/* backup from the <NL> 1 char */
	if (!backchar(0, 1))
		return FALSE;

	/* back up until we aren't in a word,
	   make sure there is a break in the line */
	cnt = 0;
	while (((c = lgetc(curwp->w_dotp, curwp->w_doto)) != ' ')
	       && (c != '\t')) {
		cnt++;
		if (!backchar(0, 1))
			return FALSE;
		/* if we make it to the beginning, start a new line */
		if (curwp->w_doto == 0) {
			gotoeol(FALSE, 0);
			return lnewline();
		}
	}

	/* delete the forward white space */
	if (!forwdel(0, 1))
		return FALSE;

	/* put in a end of line */
	if (!lnewline())
		return FALSE;

	/* and past the first word */
	while (cnt-- > 0) {
		if (forwchar(FALSE, 1) == FALSE)
			return FALSE;
	}
	return TRUE;
}

/* Move the cursor backward by "n" words. All of the details of motion are
 * performed by the "backchar" and "forwchar" routines. Error if you try to
 * move beyond the buffers.
 */
int backword( int f, int n) {
	if( n < 0)
		return forwword( f, -n) ;

	if( backchar( FALSE, 1) == FALSE)
		return FALSE ;

	while( n--) {
		while( !inword())
			if( backchar( FALSE, 1) == FALSE)
				return FALSE ;

		do {
			if( backchar( FALSE, 1) == FALSE)
				return FALSE ;
		} while( inword()) ;
	}

	return forwchar( FALSE, 1) ;
}

/* Move the cursor forward by the specified number of words. All of the motion
 * is done by "forwchar". Error if you try and move beyond the buffer's end.
 */
int forwword( int f, int n) {
	if( n < 0)
		return backword( f, -n) ;

	while( n--) {
		while( inword())
			if( forwchar( FALSE, 1) == FALSE)
				return FALSE ;

		do {
			if( forwchar( FALSE, 1) == FALSE)
				return FALSE ;
		} while( !inword()) ;
	}

	return TRUE ;
}

/* Word capitalize, to upper and to lower
*/
static boolean uniflip( boolean toupper_f) {	/* flip unicode case and forward */
	unicode_t	c ;
	int	len ;

	len = lgetchar( &c) ;	/* len => unicode or extended ASCII */
	if( (c <= 255) && ( toupper_f ? islower( c) : isupper( c))) {
		c = flipcase( c) ;
		ldelchar( 1, FALSE) ;
		if( len == 1)
			linsert_byte( 1, c) ;
		else
			linsert( 1, c) ;

		lchange( WFHARD) ;
	} else
		if( forwchar( FALSE, 1) == FALSE)
			return FALSE ;

	return TRUE ;
}

static boolean capcapword( int n, boolean first_f, boolean rest_f) {
	if( curbp->b_mode & MDVIEW)	/* don't allow this command if      */
		return rdonly() ;		/* we are in read only mode     */

	if( n < 0)
		return FALSE ;

	while( n--) {
		while( !inword())
			if( forwchar( FALSE, 1) == FALSE)
				return FALSE ;

		if( !uniflip( first_f))
			return FALSE ;

		while( inword())
			if( !uniflip( rest_f))
				return FALSE ;
	}

	return TRUE ;
}

/* Move the cursor forward by the specified number of words. As you move,
 * convert any characters to upper case. Error if you try and move beyond the
 * end of the buffer. Bound to "M-U".
 */
int upperword( int f, int n) {
	return capcapword( n, TRUE, TRUE) ;
}


/* Move the cursor forward by the specified number of words. As you move
 * convert characters to lower case. Error if you try and move over the end of
 * the buffer. Bound to "M-L".
 */
int lowerword( int f, int n) {
	return capcapword( n, FALSE, FALSE) ;
}

/* Move the cursor forward by the specified number of words. As you move
 * convert the first character of the word to upper case, and subsequent
 * characters to lower case. Error if you try and move past the end of the
 * buffer. Bound to "M-C".
 */
int capword( int f, int n) {
	return capcapword( n, TRUE, FALSE) ;
}

/*
 * Kill forward by "n" words. Remember the location of dot. Move forward by
 * the right number of words. Put dot back where it was and issue the kill
 * command for the right number of characters. With a zero argument, just
 * kill one word and no whitespace. Bound to "M-D".
 */
int delfword(int f, int n)
{
	struct line *dotp;	/* original cursor line */
	int doto;	/*      and row */
	int c;		/* temp char */
	long size;		/* # of chars to delete */

	/* don't allow this command if we are in read only mode */
	if (curbp->b_mode & MDVIEW)
		return rdonly();

	/* ignore the command if there is a negative argument */
	if (n < 0)
		return FALSE;

	/* Clear the kill buffer if last command wasn't a kill */
	if ((lastflag & CFKILL) == 0)
		kdelete();
	thisflag |= CFKILL;	/* this command is a kill */

	/* save the current cursor position */
	dotp = curwp->w_dotp;
	doto = curwp->w_doto;

	/* figure out how many characters to give the axe */
	size = 0;

	/* get us into a word.... */
	while (inword() == FALSE) {
		if (forwchar(FALSE, 1) == FALSE)
			return FALSE;
		++size;
	}

	if (n == 0) {
		/* skip one word, no whitespace! */
		while (inword() == TRUE) {
			if (forwchar(FALSE, 1) == FALSE)
				return FALSE;
			++size;
		}
	} else {
		/* skip n words.... */
		while (n--) {

			/* if we are at EOL; skip to the beginning of the next */
			while (curwp->w_doto == llength(curwp->w_dotp)) {
				if (forwchar(FALSE, 1) == FALSE)
					return FALSE;
				++size;
			}

			/* move forward till we are at the end of the word */
			while (inword() == TRUE) {
				if (forwchar(FALSE, 1) == FALSE)
					return FALSE;
				++size;
			}

			/* if there are more words, skip the interword stuff */
			if (n != 0)
				while (inword() == FALSE) {
					if (forwchar(FALSE, 1) == FALSE)
						return FALSE;
					++size;
				}
		}

		/* skip whitespace and newlines */
		while ((curwp->w_doto == llength(curwp->w_dotp)) ||
		       ((c = lgetc(curwp->w_dotp, curwp->w_doto)) == ' ')
		       || (c == '\t')) {
			if (forwchar(FALSE, 1) == FALSE)
				break;
			++size;
		}
	}

	/* restore the original position and delete the words */
	curwp->w_dotp = dotp;
	curwp->w_doto = doto;
	return ldelete(size, TRUE);
}

/*
 * Kill backwards by "n" words. Move backwards by the desired number of words,
 * counting the characters. When dot is finally moved to its resting place,
 * fire off the kill command. Bound to "M-Rubout" and to "M-Backspace".
 */
int delbword(int f, int n)
{
	long size;

	/* don't allow this command if we are in read only mode */
	if (curbp->b_mode & MDVIEW)
		return rdonly();

	/* ignore the command if there is a nonpositive argument */
	if (n <= 0)
		return FALSE;

	/* Clear the kill buffer if last command wasn't a kill */
	if ((lastflag & CFKILL) == 0)
		kdelete();
	thisflag |= CFKILL;	/* this command is a kill */

	if (backchar(FALSE, 1) == FALSE)
		return FALSE;
	size = 0;
	while (n--) {
		while (inword() == FALSE) {
			if (backchar(FALSE, 1) == FALSE)
				return FALSE;
			++size;
		}
		while (inword() != FALSE) {
			++size;
			if (backchar(FALSE, 1) == FALSE)
				goto bckdel;
		}
	}
	if (forwchar(FALSE, 1) == FALSE)
		return FALSE;
      bckdel:return ldelchar(size, TRUE);
}

/*
 * Return TRUE if the character at dot is a character that is considered to be
 * part of a word. The word character list is hard coded. Should be setable.
 */
static int inword( void) {
	int c;

	if( curwp->w_doto == llength( curwp->w_dotp))
		return FALSE ;

	c = lgetc( curwp->w_dotp, curwp->w_doto) ;
	return isletter( c) || ( c >= '0' && c <= '9') ;
}

#if	WORDPRO
static int parafillnjustify( int f, int n, int justify_f) {
	unicode_t c;		/* current char during scan	*/
	unicode_t *wbuf ;	/* buffer for current word	*/
	int wbufsize ;
	int wordlen;	/* length of current word       */
	int clength;	/* position on line during fill */
	int eopflag;	/* Are we at the End-Of-Paragraph? */
	int firstflag = TRUE ;	/* first word? (needs no space) */
	struct line *eopline;	/* pointer to line just past EOP */
	int	dotflag = 0 ;		/* was the last char a period?  */
	int leftmarg = 0 ;		/* left marginal */

	if (curbp->b_mode & MDVIEW)	/* don't allow this command if      */
		return rdonly();	/* we are in read only mode     */
	if (fillcol == 0) {	/* no fill column set */
		mloutstr( "No fill column set") ;
		return FALSE;
	}

	if( justify_f) {
		leftmarg = getccol( FALSE) ;
		if (leftmarg + 10 > fillcol) {
			mloutstr( "Column too narrow") ;
			return FALSE;
		}

		justflag = justify_f ;
	}

	wbufsize = ALLOCSZ ;
	wbuf = malloc( ALLOCSZ * sizeof *wbuf) ;
	if( NULL == wbuf) {
		justflag = FALSE ;
		return FALSE ;
	}

	/* record the pointer to the line just past the EOP */
	gotoeop(FALSE, 1);
	eopline = lforw(curwp->w_dotp);

	/* and back to the beginning of the paragraph */
	gotobop(FALSE, 1);

	/* initialize various info */
	if( justflag && leftmarg < llength(curwp->w_dotp)) {
		setccol( leftmarg) ;
		lgetchar( &c) ;
		if( c == ' ' || c == '\t')
		/* on a space */
			if( getccol( TRUE) < getccol( FALSE))
			/* first non space before current position */
				firstflag = FALSE ;
	}

	clength = getccol( FALSE) ;
	wordlen = 0;

	/* scan through lines, filling words */
	eopflag = FALSE;
	while (!eopflag) {
		int bytes = 1;

		/* get the next character in the paragraph */
		if (curwp->w_doto == llength(curwp->w_dotp)) {
			c = ' ';
			if (lforw(curwp->w_dotp) == eopline)
				eopflag = TRUE;
		} else
			bytes = lgetchar(&c);

		/* and then delete it */
		ldelete(bytes, FALSE);

		/* if not a separator, just add it in */
		if (c != ' ' && c != '\t') {
			if (wordlen < wbufsize)
				wbuf[wordlen++] = c;
			else {
			/* overflow */
				unicode_t *newptr ;

				newptr = realloc( wbuf, (wbufsize + ALLOCSZ) * sizeof *wbuf) ;
				if( newptr != NULL) {
					wbuf = newptr ;
					wbufsize += ALLOCSZ ;
					wbuf[ wordlen++] = c ;
				} /* else the word is truncated silently */
			}
		} else if (wordlen) {
		/* at a word break with a word waiting */
			if( firstflag)
				firstflag = FALSE ;
			else {
			/* calculate tentative new length with word added */
				if( fillcol > clength + dotflag + 1 + wordlen) {
				/* add word to current line */
					linsert( dotflag + 1, ' ') ;	/* the space */
					clength += dotflag + 1 ;
				} else {
					/* start a new line */
					lnewline();
					linsert( leftmarg, ' ') ;
					clength = leftmarg;
				}
			}

			/* and add the word in in either case */
			for( int i = 0 ; i < wordlen ; i++) {
				c = wbuf[ i] ;
				linsert( 1, c) ;
				++clength;
			}

			dotflag = c == '.' ;	/* was the last char a period?  */
			wordlen = 0;
		}
	}

	/* and add a last newline for the end of our new paragraph */
	if( eopline == curbp->b_linep)	/* at EOF? */
		forwchar( FALSE, 1) ;
	else
		lnewline() ;

	if( justflag) {
		forwword(FALSE, 1);
		setccol( leftmarg) ;
		justflag = FALSE;
	}

	free( wbuf) ;
	return TRUE;
}

/*
 * Fill the current paragraph according to the current
 * fill column
 *
 * f and n - deFault flag and Numeric argument
 */
int fillpara( int f, int n) {
	return parafillnjustify( f, n, FALSE) ;
}

/* Fill the current paragraph according to the current
 * fill column and cursor position
 *
 * int f, n;		deFault flag and Numeric argument
 */
int justpara( int f, int n) {
	return parafillnjustify( f, n, TRUE) ;
}

/*
 * delete n paragraphs starting with the current one
 *
 * int f	default flag
 * int n	# of paras to delete
 */
int killpara(int f, int n)
{
	int status;	/* returned status of functions */

	while (n--) {		/* for each paragraph to delete */

		/* mark out the end and beginning of the para to delete */
		gotoeop(FALSE, 1);

		/* set the mark here */
		curwp->w_markp = curwp->w_dotp;
		curwp->w_marko = curwp->w_doto;

		/* go to the beginning of the paragraph */
		gotobop(FALSE, 1);
		curwp->w_doto = 0;	/* force us to the beginning of line */

		/* and delete it */
		if ((status = killregion(FALSE, 1)) != TRUE)
			return status;

		/* and clean up the 2 extra lines */
		ldelete(2L, TRUE);
	}
	return TRUE;
}


/*
 *	wordcount:	count the # of words in the marked region,
 *			along with average word sizes, # of chars, etc,
 *			and report on them.
 *
 * int f, n;		ignored numeric arguments
 */
int wordcount(int f, int n)
{
	struct line *lp;	/* current line to scan */
	int offset;	/* current char to scan */
	long size;		/* size of region left to count */
	int ch;	/* current character to scan */
	int wordflag;	/* are we in a word now? */
	int lastword;	/* were we just in a word? */
	long nwords;		/* total # of words */
	long nchars;		/* total number of chars */
	int nlines;		/* total number of lines in region */
	int avgch;		/* average number of chars/word */
	int status;		/* status return code */
	struct region region;		/* region to look at */

	/* make sure we have a region to count */
	if ((status = getregion(&region)) != TRUE)
		return status;
	lp = region.r_linep;
	offset = region.r_offset;
	size = region.r_size;

	/* count up things */
	lastword = FALSE;
	nchars = 0L;
	nwords = 0L;
	nlines = 0;
	while (size--) {

		/* get the current character */
		if (offset == llength(lp)) {	/* end of line */
			ch = '\n';
			lp = lforw(lp);
			offset = 0;
			++nlines;
		} else {
			ch = lgetc(lp, offset);
			++offset;
		}

		/* and tabulate it */
		wordflag = isletter( ch) || (ch >= '0' && ch <= '9') ;
		if (wordflag == TRUE && lastword == FALSE)
			++nwords;
		lastword = wordflag;
		++nchars;
	}

	/* and report on the info */
	if (nwords > 0L)
		avgch = (int) ((100L * nchars) / nwords);
	else
		avgch = 0;

	mloutfmt( "Words %D Chars %D Lines %d Avg chars/word %f",
		nwords, nchars, nlines + 1, avgch) ;
	return TRUE;
}

/*
 * go back to the beginning of the current paragraph
 * here we look for a <NL><NL> or <NL><TAB> or <NL><SPACE>
 * combination to delimit the beginning of a paragraph
 *
 * int f, n;		default Flag & Numeric argument
 */
int gotobop(int f, int n)
{
	if (n < 0) /* the other way... */
		return gotoeop(f, -n);

	while (n-- > 0) {  /* for each one asked for */

		/* first scan back until we are in a word */
		while( backchar( FALSE, 1) && !inword()) ;

		curwp->w_doto = 0;	/* and go to the B-O-Line */

		/* and scan back until we hit a <NL><NL> or <NL><TAB>
		   or a <NL><SPACE>                                     */
		while (lback(curwp->w_dotp) != curbp->b_linep)
			if (llength(curwp->w_dotp) != 0 &&
			    ((justflag == TRUE) ||
			     (lgetc(curwp->w_dotp, curwp->w_doto) != TAB &&
			      lgetc(curwp->w_dotp, curwp->w_doto) != ' '))
			    )
				curwp->w_dotp = lback(curwp->w_dotp);
			else
				break;

		/* and then forward until we are in a word */
		while( !inword() && forwchar( FALSE, 1)) ;
	}
	curwp->w_flag |= WFMOVE;	/* force screen update */
	return TRUE;
}

/*
 * Go forward to the end of the current paragraph
 * here we look for a <NL><NL> or <NL><TAB> or <NL><SPACE>
 * combination to delimit the beginning of a paragraph
 *
 * int f, n;		default Flag & Numeric argument
 */
int gotoeop(int f, int n)
{
	if (n < 0)  /* the other way... */
		return gotobop(f, -n);

	while (n-- > 0) {  /* for each one asked for */
		/* first scan forward until we are in a word */
		while( !inword() && forwchar( FALSE, 1)) ;
		curwp->w_doto = 0 ;						/* and go to the B-O-Line */
		if( curwp->w_dotp != curbp->b_linep)	/* of next line if not at EOF */
			curwp->w_dotp = lforw( curwp->w_dotp) ;

		/* and scan forward until we hit a <NL><NL> or <NL><TAB>
		   or a <NL><SPACE>                                     */
		while (curwp->w_dotp != curbp->b_linep) {
			if (llength(curwp->w_dotp) != 0 &&
			    ((justflag == TRUE) ||
			     (lgetc(curwp->w_dotp, curwp->w_doto) != TAB &&
			      lgetc(curwp->w_dotp, curwp->w_doto) != ' '))
			    )
				curwp->w_dotp = lforw(curwp->w_dotp);
			else
				break;
		}

		/* and then backward until we are in a word */
		while( backchar( FALSE, 1) && !inword()) ;

		curwp->w_doto = llength(curwp->w_dotp);	/* and to the EOL */
	}
	curwp->w_flag |= WFMOVE;  /* force screen update */
	return TRUE;
}
#endif

/* end of word.c */