#!/usr/bin/perl
# `jf' utility
# join files - works with `sf' to facilitate global search / replace, etc.

use strict;

my $sep = $ENV{JF_SEP} || '#File:';
#my $sep = '!)@(#*$&%^';

use IO::File;

my $dest = shift;
if (!defined $dest) {
    die "usage: jf all.txt [file1.txt ...]\nsee:   sf\n";
}

my @src = @ARGV;

if ( -e $dest &&
	(! -f _ || -s _ &&
		index(IO::File->new($dest)->
			getline(), "$sep ") != 0
	)
   ) {
die "would clobber: $dest\n";
}

my $destfh = new IO::File(">$dest")
    or die "cannot open $dest";

while (my $src = shift @src) {
    chomp $src;
    if (-T $src) {
	print "processing textfile $src\n";
	# we only want to munge text files, not binary
	my $srcfh = new IO::File($src)
	    or die "cannot open $src";
	print $destfh $sep, ' ', $src, "\n";
	while (my $line = <$srcfh>) {
	    if (index ($line, $sep) == 0) {
		substr $line, length($sep), 0, '-'; #insert a - after it to distinguish from a separator, which has a space
	    }
	    unless (substr($line, length($line)-1) eq "\n") {
		# oh no, doesn't end in a newline
		print "Oh no, doesn't end in a newline!\n";
		$line.="\n";
	    }
	    print $destfh $line;
	}
    } elsif (-d $src and $src !~ /CVS$/) {
	print "reading directory $src\n";
	opendir DIR, $src;
	push @src,  map {"$src/$_"} grep {not ($_ eq '.' or $_ eq '..')} readdir DIR;
    } else {
	print "ignoring $src\n";
    }
}

close $destfh;