#!/usr/bin/perl -w

#use lib "";
use MP3::Tag;
use File::Find;
use Time::HiRes qw(usleep);
use Getopt::Std;
use TeleServ;

$prog_name = $0;
$player_name = "/usr/bin/mpg123";
@mp3files = ();

sub getid3 {
    my $filename = shift;
    my $mp3 = MP3::Tag->new($filename);
    my @out_id3 = $mp3->autoinfo();
    return @out_id3;
}

sub formatid3 {
    my @param = @_;
    my @formats = qw(t n p a c y g);
    return if (scalar @param != 8);
    my $format_str = pop @param;
    for(my $i = 0; $i < 7; $i++) {
	$format_str =~ s/\%$formats[$i]/$param[$i]/g;
    }
    return $format_str;
}
    
sub wanted {
    /^.*\.[mM][pP]3\z/s &&
    push(@mp3files, $File::Find::name);
}

# Return string array to scroll on LCD
sub scroll_arr {
    my ($str, $num) = @_;
    my @out_arr;
    return $str if (length($str) <= 16);
    my $len = length($str) - $num;
    for( $i = 0; $i <= $len; $i++ ) {
	$out_arr[$i] = substr($str, $i, $num);
    }
    return @out_arr;
}

sub child_kill {
    my $p = shift;
    $SIG{CLD} = IGNORE;
    kill(KILL, $p) if ($p);
}

sub usage {
    print "Usage: $prog_name -d <device_name> -f <format_string> dir_name\n";
    print "\tRead man page for more detail\n";
    exit 0;
}

getopts("d:f:h",\%opts);

$opts{d} = "/dev/ttyS0" unless($opts{d});
$opts{f} = "%t" unless($opts{f});
usage() unless($opt{h} || $ARGV[0] || -d $ARGV[0]);

File::Find::find({wanted => \&wanted}, $ARGV[0]);

tsOpen($opts{d});
tsSetTerminalMode;

$mp3_ind = 0;

while (1) {
    $name_file = $mp3files[$mp3_ind];
    $print_str="Unsuported" unless ($print_str = formatid3(getid3($name_file), $opts{f}));
    @scroll = scroll_arr($print_str, 16);

    #Run player (fork)
    if( $pid = open(CHILD,"|-") ) {
	#Set $proc_exit when player is stopped
	$proc_exit = 0;
        $SIG{CLD} = sub { $proc_exit = 1; };
	#direction of scroll on LCD
	$scr_course = 1; 
	$scr_ind = 0;
	while (1) {
	    #one position scroll on LCD
	    if( $scr_course ) {
		if ($scr_ind >= scalar(@scroll) - 1) {
		    $scr_course = 0;
		} else {
		    $scr_ind++;
		}
	    } else {
		if ($scr_ind <= 0) {
		    $scr_course = 1;
		} else {
		    $scr_ind--;
		}
	    }
	    tsPrint($scroll[$scr_ind]);
	    usleep 400000;
	    #Next or Previous file playing	    
	    $key = tsKey();
	    if ($proc_exit || ($key eq "u")) {
		$mp3_ind++; 
		$mp3_ind = 0 if( $mp3_ind >= scalar(@mp3files) );
		last;
	    } elsif ($key eq "d") {
		$mp3_ind--; 
		$mp3_ind = scalar(@mp3files) - 1 if( $mp3_ind < 0 );
		last;
	    } elsif ($key eq "r") {
		tsPrint("Stop");
		child_kill $pid;
		while(tsWaitKey() ne "r") {}
		goto EXIT;
	    }
	}
	child_kill $pid;
	EXIT: 
	close CHILD;
    } else {
	exec $player_name, $name_file;
    }
}