#!/usr/bin/perl

# Copyright (c) 2014- The University of Notre Dame.
# This software is distributed under the GNU General Public License.
# See the file COPYING for details.
#
# This program runs BWA using Work Queue.  It accepts the query and reference
# sequence as arguments on the command line.

use Error qw(:try);
use Error::Simple;
use Getopt::Long qw(:config no_ignore_case);

use work_queue;

my $num_reads = 200000;

my $usage = "
wq_bwa.pl [options] <ref> <query>

	-reads <int>   Sets the number of reads per split to use for running the query (default:$num_reads).

Work Queue Options:
	-port <int>		Sets the port for work_queue to listen on (default: arbitrary).

	-fa <int>       Sets the work_queue fast abort option with the given multiplier (default: off).

	-N <project>    Sets the project name to <project> (default: none).

	-stats <file>   Prints WQ statistics to <file> (default:off).

	-d <level>      Sets the debug flag for Work Queue. For all debugging output, try 'all' (default: off).

	-help           Print this usage string.
";

#---Process options on the command line
my %OPT;
try{
	GetOptions("port=i" => \$OPT{port},
			   "fa=i" => \$OPT{fast_abort},
			   "N=s" => \$OPT{project},
			   "stats=s" => \$OPT{stats},
			   "d=s" => \$OPT{debug},
			   "help|?" => sub {print $usage; exit(0)}
	);
} catch Error::Simple with{
	my $E = shift;
	print STDERR $E->{-text};
	die "\nParsing command line options failed!\n" if();
};

if ($#ARGV < 1) {
	print $usage;
	exit 1;
}

main();

#------------------------------- FUNCTION DEFINITIONS-------------------------------------
sub setup_workqueue {
	if(defined($OPT{"debug"})){
		work_queue::cctools_debug_flags_set($OPT{"debug"});
		print localtime()." Work Queue debug flags set.\n";
	}

	my $port = 0;
	if(defined($OPT{"port"})) {
		$port = $OPT{"port"};
	}
	my $wq = work_queue::work_queue_create($port);
	if(defined($wq)) {
		$port = work_queue_port($wq);
		print localtime()." Work Queue listening on port $port.\n";
	} else {
		print STDERR "Failed to create Work Queue on port $port.\n";
		exit(0);
	}

	if(defined($OPT{"fast_abort"})) {
		my $multiplier = $OPT{"fast_abort"};
		my $fa = work_queue::work_queue_activate_fast_abort($wq,$multiplier);
		print localtime()." Work Queue fast abort set to $multiplier.\n";
	}

	if(defined($OPT{"project"})) {
		work_queue::work_queue_specify_name($wq, $OPT{"project"});
		print localtime()." Work Queue project name set to $OPT{\"project\"}.\n";
	}

	if(defined($OPT{"stats"})) {
		work_queue::work_queue_specify_log($wq, $OPT{"stats"});
		print localtime()." Work Queue stats file set to $OPT{\"stats\"}.\n";
	}

	return $wq;
}

sub split_query {
	my($query_file) = @_;

	my $read_count = 0;
	open(infile, $query_file);

	my $num_outputs = 0;
	open(outfile,">$query_file.$num_outputs");

	my $line_count=0;

	while (my $line = <infile>) {
		chomp $line;

		#a new sequence begins with '@'
		if ($line =~ /^[@]/ and $line_count % 4 ==0){
			if ($read_count == $num_reads){
				close(outfile);
				$num_outputs++;
				$read_count = 0;
				open(outfile, ">$query_file.$num_outputs");
			} else {
				$read_count++;
			}
		}

		print outfile $line;
		print outfile "\n";

		$line_count++;
	}

	close(infile);

	print localtime(). " Number of splits of $query_file is $num_outputs.\n";
	return $num_outputs-1;
}

sub partition_tasks {
	my($wq, $ref_file, $query_file) = @_;

	my $num_splits = split_query($query_file);

	for(my $i = 0; $i < $num_splits; $i++) {
		my $task_query_file = $query_file. ".$i";
		my $task_outfile = $task_query_file. ".sam";
		my $task_command = "./bwa mem $ref_file $task_query_file > $task_outfile";
		my $task = work_queue_task_create($task_command);

		work_queue_task_specify_file($task, "bwa", "bwa", $WORK_QUEUE_INPUT, $WORK_QUEUE_CACHE);

		#add the ref file indexes using two for loops
		foreach my $ending ('', '.amb', '.ann', '.bwt', '.pac', '.sa') {
			my $task_ref_file = $ref_file . $ending ;
			work_queue_task_specify_file($task, $task_ref_file, $task_ref_file, $WORK_QUEUE_INPUT, $WORK_QUEUE_CACHE);
		}

		work_queue_task_specify_file($task, $task_query_file, $task_query_file, $WORK_QUEUE_INPUT, $WORK_QUEUE_NOCACHE);
		work_queue_task_specify_file($task, $task_outfile, $task_outfile, $WORK_QUEUE_OUTPUT, $WORK_QUEUE_NOCACHE);

		my $taskid = work_queue_submit($wq, $task);
		print localtime(). " Submitted task (id# $task->{taskid}): $task->{command_line}\n";
	}

	return $num_splits;
}

sub retrieve_tasks {
	my ($wq, $num_tasks) = @_;

	my $retrieved_tasks = 0;

	print localtime(). " Waiting for $num_tasks tasks to complete...\n";
	while ($retrieved_tasks < $num_tasks) {
		my $t = work_queue_wait($wq, 5);

		if(defined($t)) {
			print localtime(). " Task (id# $t->{taskid}) complete: $t->{command_line} (return code $t->{return_status})\n";
			if($t->{return_status} != 0) {
				print localtime(). " Task (id# $t->{taskid}) failed\n";
			}

			my $task_output = $t->{output};
			open (task_outfile, '>>task_outputs.txt');
			print task_outfile "$task_output\n";
			print task_outfile "=====================================\n\n";
			close (task_outfile);

			work_queue_task_delete($t);
			$retrieved_tasks++;
			print localtime(). " Retrieved $retrieved_tasks tasks.\n";
		}
	}
}

sub merge_tasks {
	my($query_file, $num_splits) = @_;

	open(sam_outfile,">$query_file.sam");
	open(seq_outfile,">$query_file.seq");

	for(my $i = 0; $i < $num_splits; $i++) {
		my $task_outfile = $query_file. ".$i" . ".sam";
		open(outfh,$task_outfile);
		while(my $line = <outfh>)  {
			$line =~ s/^\s+//;
			$first_char = substr($line, 0, 1);
			if($first_char == '@') {
				print sam_outfile $line;
			} else {
				print seq_outfile $line;
			}
		}
		close(outfh);
	}

	close(seq_outfile);

	#open(seq_outfile, "$query_file.seq");
	#while(my $line = <seq_outfile>) {
	#	print sam_outfile $line;
	#}
	close(sam_outfile);
}

sub delete_workqueue {
	my($wq) = @_;
	work_queue_delete($wq);
}

sub main {
	my $ref_file=$ARGV[0];
	my $query_file=$ARGV[1];

	my $wq = setup_workqueue();

	my $num_tasks = partition_tasks($wq, $ref_file, $query_file);
	retrieve_tasks($wq, $num_tasks);
	merge_tasks($query_file, $num_tasks);

	delete_workqueue($wq);

	exit 0;
}
