#!/usr/bin/perl
use POSIX qw(mkfifo);
use Fcntl;
use IO::Handle;
use strict;

$|=1;
print "############\n";
my %prog;
my $infile=$ARGV[0];
my $outfile=$ARGV[1];

# get some stats
my $frametotal,$fwide,$fhigh;
open(IN,"ffprobe -show_streams '$infile' 2>/dev/null |") ||
die "$infile: $!";
while(<IN>) {
    chomp;
    $frametotal=$1 if(/^nb_frames=(\d+)/);
    $fwide=$1 if(/^width=(\d+)/);
    $fhigh=$1 if(/^height=(\d+)/);
    last if(/^\[\/STREAM\]/);
}   
close(IN);

my @acmd;
@acmd=("-acodec","libfaac","-ac","2","-ab","160k");

my @vcmd=qw/-c:v libx264 -vprofile main -preset slow -tune film -level 3.1 -crf 28 -threads 0/;
if($fwide > 1280 || $fhigh > 720) {
    @vcmd=(@vcmd,"-vf","scale=min(1280\\,iw):-1");
}

pipe(IN, OUT); # We read from IN, ffmpeg writes to OUT.
OUT->autoflush(1); # Autoflush on, close-on-exec off
my $val=fcntl(OUT,F_GETFD,0) || die "Error: fcntl GET: $!";
$val &= ~FD_CLOEXEC;
fcntl(OUT,F_SETFD,$val) || die "Error: fcntl SET: $!";
my $fd=fileno OUT;

my @cmd=("ffmpeg","-progress","pipe:$fd","-v","panic",
        "-i",$infile, @acmd,@vcmd,@metadata,$outfile);

my $pid=fork(); # Fork the kid
unless($pid) {
    die "Can't fork! $!" unless defined $pid;
    close(IN);
    exec @cmd or die "Can't exec! $!";
}
# parent.
close(OUT);

while(<IN>) {
    chomp;
    my ($a,$b)=split /=/;
    $prog{$a}=$b;

    if($a eq "progress") {
        my $pcent=$prog{"frame"}/$frametotal*100;
        my $hcent=int($pcent/2);
        my $bar="[".("#" x $hcent).(" " x (50-$hcent))." ] ";
        $bar .=sprintf("%.2f",$pcent)."% fps=".$prog{"fps"};
        print "\r$bar";
    }
}
print "\nWaiting for finish...\n";
waitpid($pid,0);