#!/usr/bin/perl -p

s{^((> )*)}{};
$level = length($1) >> 1;

if (s{^On .*, (.*) wrote:}{}) {
	$who[$level+1] = $1;
	print $level+1, " -> $1\n" if $ENV{DEBUG};
	$_ = "";
} else {
	if ($level && $level != $last_level) {
		print "@ $level\n" if $ENV{DEBUG};
		if ($_ =~ /^\s*$/) {
			print "\n";
			$_ = "";
		}
		print "$who[$level] said:\n";
	}
	if ($level && $_) {
		$_ = "> $_";
	}
}

$last_level = $level;