#!/usr/bin/perl -w
use FileHandle;
use Time::HiRes;

# Changes:
#   2006-08-04 added arrow if displayed string is too long
#   2006-08-11 fork; changed this version for 2x20 VFD
#   2006-08-11 improved line breaks and stream name removal

system ("stty -F /dev/ttyS0 9600 -ocrnl -onlcr -onlret");
open (SERIAL, ">/dev/ttyS0") || die ("Could not open serial port: $!\n");
autoflush SERIAL 1;

$oldstatus = 23;
$oldtitle = "Blubb";


while (1) {
	($status, $time, $bitrate, $channels, $pos, $len, $title) = GetInfo ();
	if ($status == 2) { # display nothing if stopped
		$title = "";
	}
	if (($oldtitle ne $title) or ($oldstatus ne $status)) {
		print (SERIAL chr(0x1F)); # reset
		Time::HiRes::usleep (5*1000);
		print (SERIAL chr(0x1B), chr(0x00), chr(0x86), chr(0x39), chr(0xEE), chr(0x62), chr(0x00)); # custom char #0 - "play"
		print (SERIAL chr(0x1B), chr(0x01), chr(0x06), chr(0xF7), chr(0xBD), chr(0xEC), chr(0x00)); # custom char #1- "pause"
		print (SERIAL chr(0x1B), chr(0x02), chr(0x07), chr(0xFF), chr(0xFF), chr(0xFC), chr(0x00)); # custom char #2 - "stop"
		print (SERIAL chr(0x14)); # cursor off
		print (SERIAL chr(0x11)); # no scrolling
		print (SERIAL chr(0x04), chr(0x40)); # brightness 40%
		$message = chr($status) . " " . $title;
		$message = strip ($message);
		if ($len < 0) { # remove stream name
			$closing = rindex ($message, ")");
			$opening = rindex ($message, "(", $closing - 1);
			if (($opening > -1) and ($closing > -1)) {
				$closing_new = $closing;
				while (1) {
					$closing_new = rindex ($message, ")", $closing_new - 1);
					if ($closing_new > $opening) {
						$opening_new = rindex ($message, "(", $opening - 1);
						if ($opening_new > -1) {
							$opening = $opening_new;
						} else {
							last;
						}
					} else {
						last;
					}
				}
				substr ($message, $opening, $closing - $opening + 1) = "";
			}
		}
		$message = strip ($message);
		print (SERIAL chr(0x10), chr(0x00)); # line 1
		$line = Line (20, 1);
		print (SERIAL $line);
		print (SERIAL chr(0x10), chr(0x14)); # line 2
		$line = Line (20, 0);
		print (SERIAL $line);
		if (length ($message) > 0) { # right arrow if text is too long
			print (SERIAL chr(0x10), chr(0x26), chr(0x20), chr(0xFA));
		}
			
		$oldstatus = $status;
		$oldtitle = $title;
	}

	sleep (1);
}

# return the first <= 20 chars of $message, splitting at spaces only if $space == 1
sub Line {
	my ($end, $line, $len, $space);
	($len, $space) = @_;
	if(length($message) <= $len) {
		$line = $message;
		$message = "";
	} else {
		$end = rindex($message, " ", $len);
		if (($end > -1) and ($space != 0)) {
			$line = substr($message, 0, $end);
			$message = substr($message, $end + 1);
		} else {
			$line = substr($message, 0, $len);
			$message = substr($message, $len);
		}
	}
	return $line;
}

# return currently playing title from XMMS info file
sub GetInfo {
	my (@info, $line, $title, $status, $pos, $len, $time, $channels, $bitrate);
	open (DATA, "/tmp/xmms-info") || return (2, "0:00", 128, 2, 0, -1, "Could not open /tmp/xmms-info: $!");
	@info = <DATA>;
	close (DATA);
	$title = "";
	$pos = 0;
	$len = -1;
	$time = "0:00";
	$channels = 2;
	$bitrate = 128;
	foreach $line (@info) {
		chomp ($line);
		if ($line =~ /^Title: /) {
			$title = substr ($line, 7);
			$title =~ s/^Title: //;
		} elsif ($line =~ /^Status: /) {
			if ($line =~ /Playing/) {
				$status = 0;
			} elsif ($line =~ /Paused/) {
				$status = 1;
			} elsif ($line =~ /Stopped/) {
				$status = 2;
			}
		} elsif ($line =~ /^uSecPosition: /) {
			$pos = substr ($line, 14);
		} elsif ($line =~ /^uSecTime: /) {
			$len = substr ($line, 10);
		} elsif ($line =~ /^Time: /) {
			$time = substr ($line, 6);
		} elsif ($line =~ /^Current bitrate: /) {
			$bitrate = substr ($line, 17) / 1000;
		} elsif ($line =~ /^Channels: /) {
			$channels = substr ($line, 10);
		}
	}
	return ($status, $time, $bitrate, $channels, $pos, $len, $title);
}

# remove trailing \n and leading and trailing spaces
sub strip {
	my ($text) = @_;
	chomp ($text);
	while ($text =~ s/^ //) { }
	while ($text =~ s/ $//) { }
	return ($text);
}