#!/usr/bin/perl

# Requirements:
#   - Need to set up location of mencoder
#   - Need to set up location of ffmpeg
#
# OS Support:
#   - Tested on windows XP SP2
#   - Tested on Mac OS X r10.4
#
# Input: AVI file
# Output: FLV file (in user's Videos directory)
# options:
#    -rotate [90,180,270]  // rotate original AVI, in degrees
#    -lint                 // print command lines, but don't execute

# GLOBALS
$opt_rotate = undef;
$opt_lint = undef;
$opt_o = undef;
$HEIGHT = 360;
$WIDTH = 480;
if ($^O eq "MSWin32") {
    $MENCODER = "c:\\Documents and Settings\\jshrall\\My Documents\\bin\\MPlayer\\mencoder.exe";
    $FFMPEG = "c:\\Documents and Settings\\jshrall\\My Documents\\bin\\ffmpeg\\bin\\ffmpeg.exe";
    $RM = "del";
    $CP = "copy";
}
elsif ($^O eq "darwin") {
    $MENCODER = "/usr/local/bin/mencoder";
    $FFMPEG = "/opt/local/bin/ffmpeg";
    $RM = "rm";
    $CP = "cp";
}
else {
    die "Sorry, I do not understand your OS: $^O.  Goodbye\n";
}

# PROGRAM
@args = &parse_args;

if (scalar @args == 0 || !-e $args[0]) {
    warn "\nERROR: Input file missing.\n";
    &help();
}

# Make file names
$input_file = $args[0];

if ($input_file !~ /\.avi$/i) {
    warn "Unsupported input file type.  Please use AVI files only\n";
    &help();
}

# tmp file is used as a temporary output file - we don't want to
# mess with the original and risk corruption!
($tmp_file = $input_file) =~ s/\.avi$/_tmp.avi/i;

if (!defined($opt_o)) {
    # Construct the output file name
    if ($^O eq "MSWin32") {
        ($output_file = $input_file) =~ s|.*\\(.*)\.avi$|$1|i;
        # Dump the file to the user's videos directory
        $output_file = $ENV{USERPROFILE} . "\\My Documents\\My Videos\\$output_file.flv";
    }
    elsif ($^O eq "darwin") {
        ($output_file = $input_file) =~ s|.*/(.*)\.avi$|$1|i;
        # Dump the file to the user's videos directory
        $output_file = $ENV{HOME} . "\\Videos\\$output_file.flv";
    }
}
else {
    $output_file = $opt_o;
}

# rotate AVI if needed
if (defined($opt_rotate)) {
    &syscall(qq!"$MENCODER" -vf rotate=$opt_rotate -o "$tmp_file" -oac copy -ovc lavc "$input_file"!);
}
else {
    &syscall(qq!$CP "$input_file" "$tmp_file"!);
}

&syscall(qq!"$FFMPEG" -i "$tmp_file" -y -b 700k -r 20 -f flv -vcodec flv -ab 56k -ar 22050 -s ${WIDTH}x$HEIGHT "$output_file"!);
&syscall(qq!$RM "$tmp_file"!);

sub parse_args {
    my (@args, $tmp);
    for ($i=0; $i<=$#ARGV; $i++) {
        if ($ARGV[$i] eq "-o") {
            $opt_o = $ARGV[++$i]
        }
        elsif ($ARGV[$i] eq "-rotate") {
            $opt_rotate = $ARGV[++$i] / 90;
            if ($opt_rotate == 1 || $opt_rotate == 3) {
                $tmp = $HEIGHT;
                $HEIGHT = $WIDTH;
                $WIDTH = $tmp;
            }
        }
        elsif ($ARGV[$i] =~ /^(-lint)$/) {
            $opt_lint = 1;
        }
        elsif ($ARGV[$i] =~ /^(-h|-help)$/) {
            &help();
        }
        else {
            push(@args, $ARGV[$i]);
        }
    }
    return @args;
}

sub help {
    print <<HELP;

 movie2blog 

 Translates an AVI into an FLV, ready for embedding into your web site.
 By default, the output file is dumped into the user's video directory.

 movie2blog [-rotate 90] input.AVI [-o output.flv]

 Options:
    -rotate [90,180,270]  // rotate original AVI, in degrees
    -lint                 // print command lines, but don't execute
    -o output.AVI         // define the destination file

Example Usage:

 movie2blog -rotate 90 input.AVI

HELP
    exit(0);
}

sub syscall {
    if ($opt_lint) {
        print "$_[0]\n";
    }
    else {
        system($_[0]);
    }
}