#!/usr/bin/perl
# Author: Alan J. Pippin
# Description: For the given srcpath, merge all the videos that were taken on the same day into a single mkv file

use File::Copy;
use File::Basename;
use Getopt::Std;
use File::stat;
use Time::localtime;

####################################################################################################
# Configuration parameters - CHANGE THESE TO SUITE YOUR NEEDS
my $compute_host = "pippin.pippins.net"; # I need this since this script is run from a virtual machine 
my $use_compute_host = 1; # Set to 1 to use a remote compute host to run the mkvmerge command. Set to 0 to use the local host to run it.
my $make_mkv = "/naspool/videos/bin/make_mkv"; # Update this to be the path to the make_mkv script
my $minage = "+10"; # Files must be older than X minutes to move
my $owner = "ajp"; # The owner of the files after they are moved
my $group = "pip"; # The group of the files after they are moved
my $mode = "664"; # The mode to set on each file after they are moved
my $video_suffix = "000"; # What number to start with when adding an incrementing suffix to the end of the video clip to avoid name collisons
my $video_title_prefix = "HomeVideos:"; # What text to put on the front of the title for the merged video being created
my $find_cmd = "find \"$srcpathname/\" -cmin $minage -iregex \".*\.mov\" -o -iregex \".*\.3gp\" -o -iregex \".*\.mp4\" -o -iregex \".*\.mts\"";
####################################################################################################

# Command line options
getopts("rh:tvs:");

sub usage {
    print "usage: $0 [-tvrh] -s <srcpath>\n";
    print "   -s <srcpath>          specify the path to search for videos to merge under\n";
    print "   -h <compute host>     specify the remote compute host to submit the mkvmerge job to\n";
    print "   -v                    verbose mode; print extra information about what is being found/merged\n";
    print "   -t                    test mode; print what will happen, but don't do anything\n";
    print "   -r                    remove merged video clips; after a merge, remove the individual video files that were merged\n";
    return 1;
}
my $srcpathname = $opt_s;
if(defined $opt_h) { usage(); exit 1; }

# Sanity checks
if(! -x $make_mkv) { die "-E- Unable to find required script: make_mkv\n"; }
if(! -d $srcpathname) { &usage; print "-E- Can't find srcpath: $srcpathname\n"; exit 1; }
if(defined $opt_h) { $compute_host = $opt_h; }

my %monthname2month = (
		       "Jan" => "01",
		       "Feb" => "02",
		       "Mar" => "03",
		       "Apr" => "04",
		       "May" => "05",
		       "Jun" => "06",
		       "Jul" => "07",
		       "Aug" => "08",
		       "Sep" => "09",
		       "Oct" => "10",
		       "Nov" => "11",
		       "Dec" => "12"
		       );

my %month2monthname = (
		       "01" => "Jan",
		       "02" => "Feb",
		       "03" => "Mar",
		       "04" => "Apr",
		       "05" => "May",
		       "06" => "Jun",
		       "07" => "Jul",
		       "08" => "Aug",
		       "09" => "Sep",
		       "10" => "Oct",
		       "11" => "Nov",
		       "12" => "Dec"
		       );

# Change directories to the srcpath to search for videos to merge
print "-> Finding all videos under '$srcpathname' to merge by day\n";
my %videos;
chdir "$srcpathname";
print "$find_cmd\n" if($opt_v);
foreach $file (sort `$find_cmd`) {

    chomp($file);
    $srcdir = dirname($file);
    $file = basename($file);
    $srcfile = $file;
    $ext = "mkv";
    
    print "Found movie: srcdir: $srcdir srcfile: $srcfile ext: $ext\n" if($opt_v);

    # Throw out files not in the current srcpath
    if((! -f "$srcfile") && (! -f "$srcdir/$srcfile")) { next; }
            
    # Make a note of the month, year, and day this video was taken (from the modification time of the file)
    $date_taken = ctime(stat("$srcdir/$srcfile")->mtime);

    # Get the date taken from the filename
    if($srcfile =~ /^(\d+)-(\d+)-(\d+)/) {
	$year = $1;
	$month = $2;
	$day = sprintf("%02d",$3);
	$monthnum = $month;
	$monthname = lc($month2monthname{$month});
    }
    # Get the date taken from the modification time
    elsif($date_taken =~ /\S+\s+(\S+)\s+(\d+)\s+\S+\s+(\d+)/) {
	$year = $3;
	$month = $1;
	$day = sprintf("%02d",$2);
	$monthnum = $monthname2month{$month};
	$monthname = lc($month2monthname{$month});
    } else {
	print "-E- Unable to parse year and month from this file: $srcdir/$srcfile\n";
	next;
    }

    # We are ready to pick a destination folder to put the merged video in
    $dstdir = $srcdir;
    $dstfile = $dstdir . "/" . $year . "-" . $monthnum . "-" . $day;

    # Check for duplicate filenames at the destination
    $newfile = $dstfile . "." . $video_suffix;
    if(-e "$newfile.$ext") {
	foreach $i ($video_suffix+1 .. '999') {
	    $newfile = $dstfile . "." . $i;
	    if(! -e "$newfile.$ext") { last; }
	}
	$dstfile = $newfile;
    }
    $dstfile = "$newfile.$ext";

    print "   merging \"$srcdir/$srcfile\" into \"$dstfile\"\n";
    push(@{$videos{"$dstfile"}}, "\"$srcdir/$srcfile\"");
}

foreach $video (sort keys %videos) {

    my $videos = join(',', @{$videos{$video}});

    # Only merge the videos if there is more than 1
    my $num_videos = $#{$videos{$video}} + 1;
    if($num_videos <= 1) { next; }
    
    if($video =~ /(\d+)-(\d+)-(\d+)/) {
	$year = $1;
	$month = $2;
	$day = sprintf("%02d",$3);
    }
    
    my $pwd = `pwd`; chomp($pwd);
    my $cmd = "";
    if($use_compute_host) { $cmd .= "ssh $compute_host 'cd \"$pwd\";"; }
    $cmd .= "$make_mkv -t \"$video_title_prefix $year-$month-$day\" -o \"$video\" -i $videos";
    if($use_compute_host) { $cmd .= "'"; }
    if(defined $opt_t) {
	print "\n-> Creating \"$video\"\n";
	print "$cmd\n";
	if(defined $opt_r) { 
	    foreach $video (@{$videos{$video}}) {
		print("rm -f $video\n");
	    }
	}
    } else {
	# Create the merged video
	my $errno = system("$cmd");
	if($errno > 0) { $errno = $errno - 255; }
	if($errno) { die "-E- make_mkv encountered some errors with exit code $errno\n"; }
	# Fix the permissions
	system("chown $owner \"$video\"");
	system("chgrp $group \"$video\"");
	system("chmod $mode \"$video\"");
	# Remove the individual video files
	if(defined $opt_r) { 
	    foreach $video (@{$videos{$video}}) {
		system("rm -f $video");
	    }
	}
    }
}