#!usr/local/bin/perl

# Perl program that replaces paragraph tags for paragraphs that contain
# textlines with changebars
# Paragraphs that contain changed lines have the tag replaced with
# <old-tag>_New
#
# Copyright Jesper Storm Bache, 1998 (jesper@bache.com)
# For license to use see "HelpWare" clause on:
# www.bache.com/sgml.html
#
# Version 0.8
#
# ======= Subroutines ========

# This procedure reads all the lines that are associated with
# a footnote or a paragraph or a table cell
sub readPara {
	undef @a;
	$a[0]="not used";
	$lineno=0;
	if ($_[0]) {
		$theType="Para";
	}
	else {
		$theType="FNote";
	}
	$a[++$lineno]=" <$theType";
	while (<>) {
		chomp;
		$a[++$lineno]=$_;
		last if /^\s+\> \# end of $theType\s*$/;
	}
}

# This function scans the lines associated with a paragraph/Footnote
# and returns true if one or more lines have a changebar
# otherwise the function returns false
sub paraHasChangeBar {
	$i=1;
	while ($i<=$lineno-3) {
		# If you use font overrides you might want to delete
		# the following two lines. I.e. the <Font check and the <FTag check
		next if (!($a[$i++]=~/^\s+\<Font/));
		next if (!($a[$i++]=~/^\s+\<FTag \`/));
		next if (!($a[$i++]=~/^\s+\<FChangeBar Yes\>/));
		return 1;
	}
	return 0;
}

# ======= Main loop ========
# The outher loop runs through the MIF until a textflow is
# encountered. When a text flow is found the inner loop is activated
# The inner loop reads the paragraphs from the text flow, and
# checks if any line in the paragraph has a changebar.
# If a changebar is found the paragrapg tag is changed to
# <paragraphname>_New

while (<>) {
	# Copy until start of textflow
	while (!/^\<TextFlow/ && !/^\<Tbls/) {
		print $_;
		last if /\# End of MIFFile\s*$/;
		$_=<STDIN>;
	}
	last if /\# End of MIFFile\s*$/;
	
	print $_;		# This is equal to the <TextFlow / <Tbls line

	$_=<STDIN>;	# Get tag of text flow
	print $_;

	# Don't parse the HTML textflows
	next if /^ \<TFTag \`HTML\'\>/;

	# Deal with the contents of the textflow
	while (<>) {
		# If the textflow ended exit the inner loop
		if (/\> # end of TextFlow\s*$/ || /\> # end of Tbls\s*$/) {
			print $_;
			last;
		}

		# skip to the next para/footnote
		$isPara = /^\s+\<Para/;
		if (!($isPara)) {
			$isFootNote = /^\s+\<FNote/;
		}
		else {
			$isFootNote = false;
		}
		if ($isPara || $isFootNote) {
			# read the contents of the paragraph / footnote
			readPara($isPara);
			$ChangeTag = paraHasChangeBar;
			
			# write the contents back out, and change the paragraph tag
			# if a changebar was found
			for ($i=1; $i<=$lineno ; $i++) {
				if ($ChangeTag && ($a[$i]=~/  \<PgfTag \`(\w+)\'\>/)) {
					print "  <PgfTag \`$1_New\'>\n";
				}
				else {
					print "$a[$i]\n";
				}
			}
		}
		else {
			print $_;
		}
	}
}