use Win32;
use Win32::SqlServer;
use Win32::Daemon;
use POE::Component::JobQueue;
use POE::Component::Log4perl;
use POE::Component::Daemon::Win32;
use POE qw( Wheel::Run::Win32 Filter::Line);

sub _start {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];
    chdir $workdir;

    POE::Component::Log4perl->spawn(
        Alias => 'logger',
        Category => 'default',
        ConfigFile => $config
    );        

    POE::Component::Daemon::Win32->spawn (
        Callback => {
            not_ready     => \&service_default_callback,
            start_pending => \&service_start_pending,
            running       => \&service_running,
            pause_pending => \&service_default_callback,
            paused        => \&service_default_callback,
            continue_pending=> \&service_default_callback,
            stop_pending  => \&service_stop_pending,
            stoppped      => \&service_stopped,
            shutdown      => \&service_shutdown
        }
    );
    
    POE::Component::JobQueue->spawn
        ( Alias         => 'queue',         
          WorkerLimit   => $max_jobs,        
          Worker        => \&make_a_worker,
          Active        => { PollInterval => $poll_interval }
        );
}

sub _stop {
    POE::Kernel->call('logger'=>info=>"service stopped");
}

sub service_stop_pending {
    POE::Kernel->post('logger'=>debug=>"call to stop_pending");
    POE::Kernel->yield('next_state');
}

sub service_running{
    POE::Kernel->yield('next_state');
}

#### other callbacks are similar, all yield('next_state')

sub make_a_worker {
        my $meta_postback = shift;
        my $file_name = shift @file_queue; 

        POE::Session->create( 
            inline_states => {
                _start    => \&worker_start,
                _stop     => sub {      },
                worker_child_stdout => \&worker_child_stdout,
                worker_closed_ffmpeg=> \&worker_closed_ffmpeg, 
                worker_closed_asr   => \&worker_closed_asr,
                sig_child           => \&sig_child
            },
            args          => [ $postback, $file_name ]
        );
}

sub worker_start
{
    my ($kernel, $session, $heap, @args ) = @_[KERNEL, SESSION, HEAP, ARG0 .. $#_];
    $heap->{postback} = $args[0]; 
    $heap->{cmdline} = POE::Wheel::Run::Win32->new(
        Program         => $ffmpeg,
        ProgramArgs     => \@ffmpeg_args,
        StdoutEvent     => "worker_child_stdout",
        StderrEvent     => "worker_child_stdout",
        CloseEvent      => "worker_closed_ffmpeg",
        StdioFilter  => POE::Filter::Line->new(),    # Child speaks in lines.
        StderrFilter => POE::Filter::Line->new(),    # Child speaks in lines.
    ); 
    
    $kernel->sig_child($heap->{cmdline}->PID, "sig_child");
    POE::Kernel->post('logger'=>info=>"session ".$session->ID." start ffmpeg ".join(' ',@ffmpeg_args));
}

sub worker_child_stdout  ### processes the output of the ffmpeg and puts the lines to the log, I can see - ffmpeg is running.

sub sig_child
{
    my ( $heap, $sig, $pid, $exit_val ) = @_[ HEAP, ARG0, ARG1, ARG2 ];
    
    my $d = delete $heap->{cmdline} if $exit_val;
 
    POE::Kernel->post('logger'=>debug=>"session ".$heap->{SessionID}." sig_child: sig=$sig, pid=$pid, exit_val=$exit_val");
    print "sig_child: sig=$sig, pid=$pid, exit_val=$exit_val\n";
 
    return 0;
}

my @handlers = qw(
  _start _stop 
);

POE::Session->create( package_states => [ main => \@handlers ] );
POE::Kernel->run();
POE::Kernel->call( 'queue' => 'stop' );
exit 0;

__END__