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

# Changes:
#   2006-08-04 added arrow if displayed string is too long
#   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;

$oldpos = -2;
$oldstatus = 23;
$oldtitle = "Blubb";

while (1) {
	($status, $time, $bitrate, $channels, $pos, $len, $title) = GetInfo ();
	if ($status == 2) { # stopped
		$title = "";
	}
	if ($len > 0) {
		$pos = int ((51 / $len) * $pos);
	} else {
		$pos = -1;
	}
	if ($oldtitle ne $title) {
		LCDInit (1);
		LCDInit (2);
		LCDChars (1);
		LCDCmd (0x01, 1);
		LCDCmd (0x01, 2);
		LCDCmd (0x80 + 2, 1);
		if ($status != 2) {
			if ($len > 0) {
				while (length ($time) < 6) {
					$time = " $time";
				}
				LCDSend ($time, 1);
			} else {
				LCDSend ("  N/A ");
			}
			LCDSend (sprintf (" %3dk", $bitrate), 1);
			if ($channels == 1) {
				LCDSend (" MO ", 1);
			} else {
				LCDSend (" ST ", 1);
			}
			$message = $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);
			LCDCmd (0xC0, 1);
			LCDSend (LCDLine (27, 1), 1);
			LCDCmd (0x80, 2);
			LCDSend (LCDLine (27, 1), 2);
			LCDCmd (0xC0, 2);
			LCDSend (LCDLine (27, 0), 2);
			if (length ($message) > 0) {
				LCDCmd (0xC0 + 25, 2);
				LCDChr (0x20, 2);
				LCDChr (0x7E, 2);
			}
		}
		$oldstatus = 23;
		$oldtitle = $title;
		$oldpos = -2;
	}
	if ($status != $oldstatus) {
		LCDCmd (0x80, 1);
		LCDChr ($status, 1);
		$oldstatus = $status;
	}
	if ($pos != $oldpos) {
		$newpos = $pos;
		LCDCmd (0x80 + 17, 1);
		if ($pos >= 0) {
			for ($num = 0; $num < 10; $num++) {
				if ($newpos >= 5) {
					LCDChr (255, 1);
					$newpos -= 5;
				} elsif ($newpos == 0) {
					LCDChr (32, 1);
				} else {
					LCDChr ($newpos + 2, 1);
					$newpos = 0;
				}
			}
		} else {
			LCDSend ("          ");
		}
		$oldpos = $pos;
	}

	sleep (1);
}

# initialize the LCD
sub LCDInit {
	my($ctrl, $val);
	($ctrl) = @_;
	print (SERIAL chr (0x80 + 25)); # contrast
	$val = 0;
	if($ctrl == 2) {
		$val = 0x40;
	}
	print (SERIAL chr (0x03 | $val));
	Time::HiRes::usleep (10*1000);
	print (SERIAL chr (0x03 | $val));
	Time::HiRes::usleep (15*1000);
	print (SERIAL chr (0x03 | $val));
	print (SERIAL chr (0x02 | $val));
	LCDCmd (0x2A, $ctrl);
	LCDCmd (0x01, $ctrl);
	Time::HiRes::usleep (15*1000);
	LCDCmd (0x02, $ctrl);
	Time::HiRes::usleep (15*1000);
	LCDCmd (0x06, $ctrl);
	LCDCmd (0x0C, $ctrl);
}

# initialize custom characters
sub LCDChars {
	my ($ctrl);
	($ctrl) = @_;
	LCDCmd (0x40, $ctrl);
	
	LCDChr (0x10, $ctrl); # 0 = play
	LCDChr (0x18, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x18, $ctrl);
	LCDChr (0x10, $ctrl);
	LCDChr (0x00, $ctrl);
	
	LCDChr (0x00, $ctrl); # 1 = pause
	LCDChr (0x1B, $ctrl);
	LCDChr (0x1B, $ctrl);
	LCDChr (0x1B, $ctrl);
	LCDChr (0x1B, $ctrl);
	LCDChr (0x1B, $ctrl);
	LCDChr (0x00, $ctrl);
	LCDChr (0x00, $ctrl);
	
	LCDChr (0x00, $ctrl); # 2 = stop
	LCDChr (0x1F, $ctrl);
	LCDChr (0x1F, $ctrl);
	LCDChr (0x1F, $ctrl);
	LCDChr (0x1F, $ctrl);
	LCDChr (0x1F, $ctrl);
	LCDChr (0x00, $ctrl);
	LCDChr (0x00, $ctrl);

	LCDChr (0x10, $ctrl); # 3 = progress block 1px
	LCDChr (0x10, $ctrl);
	LCDChr (0x10, $ctrl);
	LCDChr (0x10, $ctrl);
	LCDChr (0x10, $ctrl);
	LCDChr (0x10, $ctrl);
	LCDChr (0x10, $ctrl);
	LCDChr (0x10, $ctrl);

	LCDChr (0x18, $ctrl); # 4 = progress block 2px
	LCDChr (0x18, $ctrl);
	LCDChr (0x18, $ctrl);
	LCDChr (0x18, $ctrl);
	LCDChr (0x18, $ctrl);
	LCDChr (0x18, $ctrl);
	LCDChr (0x18, $ctrl);
	LCDChr (0x18, $ctrl);

	LCDChr (0x1C, $ctrl); # 5 = progress block 3px
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1C, $ctrl);
	LCDChr (0x1C, $ctrl);

	LCDChr (0x1E, $ctrl); # 6 = progress block 4px
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1E, $ctrl);
	LCDChr (0x1E, $ctrl);

	LCDCmd (0x80, $ctrl);
}

# send a line to the LCD
sub LCDSend {
	my ($line, $ctrl, $len, $num, $char);
	($line, $ctrl) = @_;
	$len = length($line);
	for ($num = 0; $num < $len; $num++) {
		$char = ord (substr ($line, $num, 1));
		LCDChr ($char, $ctrl);
	}
}

# send a command to the LCD
sub LCDCmd {
	my ($cmd, $ctrl, $cmd1, $cmd2);
	($cmd, $ctrl) = @_;
	$cmd1 = $cmd / 16;
	$cmd2 = $cmd % 16;
	if ($ctrl == 2) {
		$cmd1 += 0x40;
		$cmd2 += 0x40;
	}
	print (SERIAL chr($cmd1), chr($cmd2));
}

# send a character to the LCD
sub LCDChr {
	my ($char, $ctrl, $cmd1, $cmd2);
	($char, $ctrl) = @_;
	$cmd1 = $char / 16 + 0x10;
	$cmd2 = $char % 16 + 0x10;
	if ($ctrl == 2) {
		$cmd1 += 0x40;
		$cmd2 += 0x40;
	}
	print (SERIAL chr($cmd1), chr($cmd2));
}

# return the first <= 27 chars of $message, splitting at spaces if possible
sub LCDLine { 
	my($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);
}