Personal Command Line Everything (review)

Having just found this intriguing little program, I tried it and discovered that a couple lines had lost their angle brackets (due to HTML fubar somewhere along the line), there was an odd issue with pipelinks (because of two regexen applied sequentially), and saw the opportunity to add ANSI color codes to visually differentiate the output (on supporting terminals, such as gnome-terminal). The variables for the link underline and colors (change to suit your taste!) are at the top of the file.

Here is the updated code. I will leave it as an exercise for the reader to get a diff. Credit goes to lenz for writing the original.

#!/usr/bin/env perl
use strict;

my $node_now;
my $command_line  = 'pcle' or $ARGV[1];
my $system_editor = 'vim'; #change this to suit your needs
my $color_system = '33;1';  # yellow, bold
my $color_header = '34;1';  # blue, bold
my $color_link = '4';  # underline
my @node_info;
my @visited_nodes;
my $pcle_ver = '0.3';

my $help = << "__HELP__";
\x1b[${color_system}m
This is Personal Command-Line Everything version $pcle_ver
created by lenz, updated by raincomplex

Commands are as follows:
 - 'help' prints this message
 - 'quit' or 'bye' exits PCLE
 - 'latest' shows latest nodes ('latest 3' shows latest 3 nodes)
 - 'history' shows node history ('history 3' shows latest 3 entries)
 - 'new' creates a node
 - 'edit' edits a node
 - enter node number (like '3' or '#3') or name to reach it.
 - enter '-1', '-2' to navigate backwards 
\x1b[0m
__HELP__

print $help;
print loadNode( $command_line );

for(;;) {
	print "> ";
	$command_line = lc <>;
	
	exit if $command_line =~ /^quit|bye/i;
    
    if ($command_line =~ /^(edit|new) (.+?)$/i) {
    	createNode( $2 );
    	$command_line = $2;	
    };

	if ($command_line =~ /^latest\s*(\d*)$/i) {
		latestNodes( $1 || 99999 );
    	$command_line = '';	
	}
	
	if ($command_line =~ /^history\s*(\d*)$/i) {
		showHistory( $1 || 99999 );
    	$command_line = '';	
	}
	
	
	
	if ($command_line =~ /^help$/i) {
		print $help;
    	$command_line = '';	
	}
	
	if ($command_line =~ /^#*\s*(\d+)/i) {
		$command_line = $node_info[$1];
	}
	
	if ($command_line =~ /^-(\d+)/i) {
		$command_line = $visited_nodes[-$1 - 1];
	}
	
		
	print loadNode( $command_line );
}




sub loadNode() {
	my ($nodeName) = @_;
	chomp $nodeName;
	
	return if length($nodeName) == 0;
		
	my $nodePath = lc $nodeName . ".node";
	my $n = "\x1b[${color_header}mNode '$nodeName' - ";
	my $dt;
		
	if ( -f $nodePath ) {
		undef @node_info;
		open F, $nodePath or die "$! $nodePath";
		$n .= localtime( (stat( $nodePath ))[9] ) . "\n";
		$n .= ('-' x (-8 + length $n)) . "\x1b[0m\n";
		
		while (<F>) {
			$n .= $_;
		}
		close F;
		
		# replace and number bracketed stuff
		$n =~ s/\[([^\[\]]+?)(\|[^\[\]]+?)?\]/doSubst($1, $2)/gime;
		
		push @visited_nodes, $nodeName;
	} else {
		$n = "\x1b[${color_system}mThe node '$nodeName' does not exist\nType 'new $nodeName' to create it.\x1b[0m\n";
	}
	return $n . "\n";
}

sub doSubst() {
	my ($n, $t) = @_;
	if (!$t) { $t = $n; }  # regular links: display text = link text
	else { $t = substr $t, 1; }  # remove pipes from display text
	push @node_info, $n;
	return "\x1b[${color_link}m$t\x1b[0m[" . $#node_info . "]";
}
	


sub createNode() {
	my ($nodeName) = @_;
	chomp $nodeName;
	my $nodePath = lc $nodeName . ".node";
	
	system( "$system_editor $nodePath" );

}

sub latestNodes() {
	my ($howMany) = @_;
	
	my @files = glob( '*.node' );
	my %dtupd;
	my $n = 0;
	
	foreach my $f (@files) {
		my $tm = (stat( $f ))[9] ;
		$dtupd{ $tm . ':' . $n++ } = $1 if $f =~ /(.+)\.node/i;
	}	

	$n = 0;
	foreach my $f (reverse sort keys %dtupd ) {
		last if ($n++ >= $howMany);
		my ($d) = split /:/, $f;
		print localtime( $d ) . "  - " . $dtupd{$f} . "\n";
	}
}

sub showHistory() {
	my ($howMany) = @_;
	my @cmd = reverse @visited_nodes;
	my $i = 0;
	
	foreach my $n (@cmd[0..$howMany]) {
		last if length($n) == 0;
		print "-$i: $n\n";
		$i++;
	}
}