/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)pr_comment.c	5.3 (Berkeley) 9/8/85";
#endif not lint

/*-
 *
 *			  Copyright (C) 1976
 *				by the
 *			  Board of Trustees
 *				of the
 *			University of Illinois
 *
 *			 All rights reserved
 *
 *
 * NAME:
 *	pr_comment
 *
 * FUNCTION:
 *	This routine takes care of scanning and printing comments.
 *
 * ALGORITHM:
 *	1) Decide where the comment should be aligned, and if lines should
 *	   be broken.
 *	2) If lines should not be broken and filled, just copy up to end of
 *	   comment.
 *	3) If lines should be filled, then scan thru input_buffer copying
 *	   characters to com_buf.  Remember where the last blank, tab, or
 *	   newline was.  When line is filled, print up to last blank and 
 *	   continue copying.
 *
 * HISTORY:
 *	November 1976	D A Willcox of CAC	Initial coding
 *	12/6/76		D A Willcox of CAC	Modification to handle 
 *						UNIX-style comments
 *
 */

/*
 * this routine processes comments.  It makes an attempt to keep comments
 * from going over the max line length.  If a line is too long, it moves
 * everything from the last blank to the next comment line.  Blanks and
 * tabs from the beginning of the input line are removed 
 */

#include "indent_globs.h";


pr_comment()
{
    int         now_col;	/* column we are in now */
    int         adj_max_col;	/* Adjusted max_col for when we decide to
				 * spill comments over the right margin */
    int         col_1_com;	/* this comment should not be touched */
    char       *last_bl;	/* points to the last blank in the output
				 * buffer */
    char        achar;
    char       *t_ptr;		/* used for moving string */
    int         unix_comment;	/* tri-state variable used to decide if it
				 * is a unix-style comment. 0 means only
				 * blanks since /*, 1 means regular style
				 * comment, 2 means unix style comment */
    int         break_delim = comment_delimiter_on_blankline;
    int		l_just_saw_decl = ps.just_saw_decl;
    /*
     * int         ps.last_nl = 0;	/* true iff the last significant
     * thing weve seen is a newline 
     */
    int         one_liner = 1;	/* true iff this comment is a one-liner */
    adj_max_col = max_col;
    ps.just_saw_decl = 0;
    last_bl = 0;		/* no blanks found so far */
    ps.box_com = col_1_com = false;	/* at first, assume that we are
					 * not in a boxed comment or some
					 * other comment that should not
					 * be touched */
    ++ps.out_coms;		/* keep track of number of comments */
    unix_comment = 1;		/* set flag to let us figure out if there
				 * is a unix-style comment ** DISABLED:
				 * use 0 to reenable this hack! */

    /* Figure where to align and how to treat the comment */

    if (ps.col_1 && !format_col1_comments) {	/* if comment starts in
						 * column 1 it should not
						 * be touched */
	col_1_com = ps.box_com = true;
	ps.com_col = 1;
    } else {
	if (*buf_ptr == '-' || *buf_ptr == '*') {
	    ps.box_com = true;	/* a comment with a '-' or '*' immediately
				 * after the /* is assumed to be a boxed
				 * comment */
	    col_1_com = true;
	    break_delim = 0;
	}
	if ( /* ps.bl_line && */ (s_lab == e_lab) && (s_code == e_code)) {
	    /* klg: check only if this line is blank */
	    /*
	     * If this (*and previous lines are*) blank, dont put comment
	     * way out at left 
	     */
	    ps.com_col = (ps.ind_level - ps.unindent_displace) * ps.ind_size + 1;
	    adj_max_col = block_comment_max_col;
	    if (ps.com_col <= 1)
		ps.com_col = 1 + !format_col1_comments;
	} else {
	    register    target_col;
	    break_delim = 0;
	    if (s_code != e_code)
		target_col = count_spaces(compute_code_target(), s_code);
	    else {
		target_col = 1;
		if (s_lab != e_lab)
		    target_col = count_spaces(compute_label_target(), s_lab);
	    }
	    ps.com_col = ps.decl_on_line || ps.ind_level == 0 ? ps.decl_com_ind : ps.com_ind;
	    if (ps.com_col < target_col)
		ps.com_col = ((target_col + 7) & ~7) + 1;
	    if (ps.com_col + 24 > adj_max_col)
		adj_max_col = ps.com_col + 24;
	}
    }
    if (ps.box_com) {
	buf_ptr[-2] = 0;
	ps.n_comment_delta = 1 - count_spaces(1, in_buffer);
	ps.comment_delta = 0;
	buf_ptr[-2] = '/';
    } else {
	ps.n_comment_delta = 0;
	ps.comment_delta = 0;
	while (*buf_ptr == ' ' || *buf_ptr == '\t')
	    buf_ptr++;
    }
    ps.comment_delta = 0;
    *e_com++ = '/';		/* put '/*' into buffer */
    *e_com++ = '*';
    if (*buf_ptr != ' ' && !ps.box_com)
	*e_com++ = ' ';

    *e_com = '\0';
    now_col = count_spaces(ps.com_col, s_com);	/* figure what column we
						 * would be in if we
						 * printed the comment now */

    /* Start to copy the comment */

    while (1) {			/* this loop will go until the comment is
				 * copied */
	if (*buf_ptr > 040 && *buf_ptr != '*')
	    ps.last_nl = 0;
	switch (*buf_ptr) {	/* this checks for various spcl cases */
	    case 014:		/* check for a form feed */
		if (!ps.box_com) {	/* in a text comment, break the
					 * line here */
		    ps.use_ff = true;
		    /* fix so dump_line uses a form feed */
		    dump_line();
		    last_bl = 0;
		    *e_com++ = ' ';
		    *e_com++ = '*';
		    *e_com++ = ' ';
		    while (*++buf_ptr == ' ' || *buf_ptr == '\t');
		} else {
		    if (++buf_ptr >= buf_end)
			fill_buffer();
		    *e_com++ = 014;
		}
		break;

	    case '\n':
		if (had_eof) {	/* check for unexpected eof */
		    printf("Unterminated comment\n");
		    *e_com = '\0';
		    dump_line();
		    return;
		}
		one_liner = 0;
		if (ps.box_com || ps.last_nl) {	/* if this is a boxed
						 * comment, we dont ignore
						 * the newline */
		    if (s_com == e_com) {
			*e_com++ = ' ';
			*e_com++ = ' ';
		    }
		    *e_com = '\0';
		    if (!ps.box_com && e_com - s_com > 3) {
			if (break_delim == 1 && s_com[0] == '/'
			    && s_com[1] == '*' && s_com[2] == ' ') {
			    char       *t = e_com;
			    break_delim = 2;
			    e_com = s_com + 2;
			    *e_com = 0;
			    if (blanklines_before_blockcomments) prefix_blankline_requested = 1;
			    dump_line();
			    e_com = t;
			    s_com[0] = s_com[1] = s_com[2] = ' ';
			}
			dump_line();
			*e_com++ = ' ';
			*e_com++ = ' ';
		    }
		    dump_line();
		    now_col = ps.com_col;
		} else {
		ps.last_nl = 1;
		if (unix_comment != 1) {	/* we not are in
						 * unix_style comment */
		    if (unix_comment == 0 && s_code == e_code) {
			/*
			 * if it is a UNIX-style comment, ignore the
			 * requirement that previous line be blank for
			 * unindention 
			 */
			ps.com_col = (ps.ind_level - ps.unindent_displace) * ps.ind_size + 1;
			if (ps.com_col <= 1)
			    ps.com_col = 2;
		    }
		    unix_comment = 2;	/* permanently remember that we
					 * are in this type of comment */
		    dump_line();
		    ++line_no;
		    now_col = ps.com_col;
		    *e_com++ = ' ';
		    /*
		     * fix so that the star at the start of the line will
		     * line up 
		     */
		    do		/* flush leading white space */
			if (++buf_ptr >= buf_end)
			    fill_buffer();
		    while (*buf_ptr == ' ' || *buf_ptr == '\t');
		    break;
		}
		if (*(e_com - 1) == ' ' || *(e_com - 1) == '\t')
		    last_bl = e_com - 1;
		/*
		 * if there was a space at the end of the last line,
		 * remember where it was 
		 */
		else {		/* otherwise, insert one */
		    last_bl = e_com;
		    *e_com++ = ' ';
		    ++now_col;
		}
		}
		++line_no;	/* keep track of input line number */
		if (!ps.box_com) {
		    int         nstar = 1;
		    do {	/* flush any blanks and/or tabs at start
				 * of next line */
			if (++buf_ptr >= buf_end)
			    fill_buffer();
			if (*buf_ptr == '*' && --nstar >= 0) {
			    if (++buf_ptr >= buf_end)
				fill_buffer();
			    if (*buf_ptr == '/')
				goto end_of_comment;
			}
		    } while (*buf_ptr == ' ' || *buf_ptr == '\t');
		} else if (++buf_ptr >= buf_end) fill_buffer();
		break;		/* end of case for newline */

	    case '*':		/* must check for possibility of being at
				 * end of comment */
		if (++buf_ptr >= buf_end)	/* get to next char after * */
		    fill_buffer();

		if (unix_comment == 0)	/* set flag to show we are not in
					 * unix-style comment */
		    unix_comment = 1;

		if (*buf_ptr == '/') {	/* it is the end!!! */
	    end_of_comment:
		    if (++buf_ptr >= buf_end)
			fill_buffer();

		    if (*(e_com - 1) != ' ' && !ps.box_com) {	/* insure blank before
								 * end */
			*e_com++ = ' ';
			++now_col;
		    }
		    if (break_delim == 1 && !one_liner && s_com[0] == '/'
			&& s_com[1] == '*' && s_com[2] == ' ') {
			char       *t = e_com;
			break_delim = 2;
			e_com = s_com + 2;
			*e_com = 0;
			    if (blanklines_before_blockcomments) prefix_blankline_requested = 1;
			dump_line();
			e_com = t;
			s_com[0] = s_com[1] = s_com[2] = ' ';
		    }
		    if (break_delim == 2 && e_com > s_com + 3
			 /* now_col > adj_max_col - 2 && !ps.box_com */ ) {
			*e_com = '\0';
			dump_line();
			now_col = ps.com_col;
		    }
		    *e_com++ = '*';
		    *e_com++ = '/';
		    *e_com = '\0';
		    ps.just_saw_decl = l_just_saw_decl;
		    return;
		} else {	/* handle isolated '*' */
		    *e_com++ = '*';
		    ++now_col;
		}
		break;
	    default:		/* we have a random char */
		if (unix_comment == 0 && *buf_ptr != ' ' && *buf_ptr != '\t')
		    unix_comment = 1;	/* we are not in unix-style
					 * comment */

		*e_com = *buf_ptr++;
		if (buf_ptr >= buf_end)
		    fill_buffer();

		if (*e_com == '\t')	/* keep track of column */
		    now_col = ((now_col - 1) & tabmask) + tabsize + 1;
		else if (*e_com == '\b')	/* this is a backspace */
		    --now_col;
		else
		    ++now_col;

		if (*e_com == ' ' || *e_com == '\t')
		    last_bl = e_com;
		/* remember we saw a blank */

		++e_com;
		if (now_col > adj_max_col && !ps.box_com && unix_comment == 1 && e_com[-1] > ' ') {
		    /* the comment is too long, it must be broken up */
		    if (break_delim == 1 && s_com[0] == '/'
			&& s_com[1] == '*' && s_com[2] == ' ') {
			char       *t = e_com;
			break_delim = 2;
			e_com = s_com + 2;
			*e_com = 0;
			    if (blanklines_before_blockcomments) prefix_blankline_requested = 1;
			dump_line();
			e_com = t;
			s_com[0] = s_com[1] = s_com[2] = ' ';
		    }
		    if (last_bl == 0) {	/* we have seen no blanks */
			last_bl = e_com;	/* fake it */
			*e_com++ = ' ';
		    }
		    *e_com = '\0';	/* print what we have */
		    *last_bl = '\0';
		    while (last_bl > s_com && last_bl[-1] < 040)
			*--last_bl = 0;
		    e_com = last_bl;
		    dump_line();

		    *e_com++ = ' ';	/* add blanks for continuation */
		    *e_com++ = ' ';
		    *e_com++ = ' ';

		    t_ptr = last_bl + 1;
		    last_bl = 0;
		    if (t_ptr >= e_com) {
			while (*t_ptr == ' ' || *t_ptr == '\t')
			    t_ptr++;
			while (*t_ptr != '\0') {	/* move unprinted part
							 * of comment down in
							 * buffer */
			    if (*t_ptr == ' ' || *t_ptr == '\t')
				last_bl = e_com;
			    *e_com++ = *t_ptr++;
			}
		    }
		    *e_com = '\0';
		    now_col = count_spaces(ps.com_col, s_com);	/* recompute current
								 * position */
		}
		break;
	}
    }
}
