#!/usr/bin/perl
use strict;
use warnings;
use Mail::Header;

# borrowed from mutt:
# http://www.mutt.org/doc/manual/manual-6.html#quote_regexp
my $quote_regex = qr/([ \t]*[|>:}#])/;
my $header = new Mail::Header;

my @raw_lines = <>;
$header->header(\@raw_lines);
my $tagged_message = '';
$tagged_message .= $header->as_string();

foreach my $raw_line (@raw_lines) {
	chomp $raw_line;
	my $tagged_line = '';
	if( my @quote_chars = ($raw_line =~ m/$quote_regex/g) ) {
		$raw_line =~ s#$quote_regex##g;	# we can strip out the quote chars now
		my $quote_depth = scalar(@quote_chars);
		$tagged_line = "<quote depth=\"$quote_depth\">$raw_line</quote>\n";
	}
	else {
		$tagged_line = "<unquoted>$raw_line</unquoted>\n";
	}
	$tagged_message .= $tagged_line;
}

print $tagged_message;