##########################################################

# OpenKore - Bus System

# Bus query object

#

# This software is open source, licensed under the GNU General Public

# License, version 2.

# Basically, this means that you're allowed to modify and distribute

# this software. However, if you distribute modified versions, you MUST

# also distribute the source code.

# See http://www.gnu.org/licenses/gpl.html for the full license.

#

# $Revision$

# $Id$

#

#########################################################################

package Bus::Query;

use strict;

use Time::HiRes qw(time);

use Modules 'register';

# Query state constants.

use constant {

WAITING => 1,

DONE => 2,

TIMEOUT => 3

};

# See $BusClient->query() for options allowed for the constructor.

sub new {

my ($class, $args) = @_;

my $self = bless $args, $class;

# Invariant: if $state == WAITING: defined($receivedEvent)

$self->{receivedEvent} = $self->{bus}->onMessageReceived->add($self, \&messageReceived);

$self->{replies} = [];

$self->{state} = WAITING;

$self->{start_time} = time;

$self->{timeout} ||= 5;

return $self;

}

sub DESTROY {

my ($self) = @_;

if ($self->{receivedEvent}) {

$self->{bus}->onMessageReceived->remove($self->{receivedEvent});

}

}

sub getState {

my ($self) = @_;

if ($self->{state} == WAITING) {

if (time - $self->{start_time} > $self->{timeout}) {

# Timeout for query reached.

$self->{bus}->onMessageReceived->remove($self->{receivedEvent});

delete $self->{receivedEvent};

if (@{$self->{replies}} > 0) {

$self->{state} = DONE;

return DONE;

} else {

$self->{state} = TIMEOUT;

return TIMEOUT;

}

} else {

return WAITING;

}

} else {

return $self->{state};

}

}

sub getReply {

my ($self) = @_;

if (@{$self->{replies}}) {

my $message = shift @{$self->{replies}};

return @{$message};

} else {

return undef;

}

}

sub messageReceived {

my ($self, undef, $message) = @_;

if ($self->{state} == WAITING && $message->{args}{SEQ} == $self->{seq} && $message->{args}{IRY}) {

# A reply has been received.

push @{$self->{replies}}, [$message->{messageID}, $message->{args}];

if (!$self->{collectAll}) {

# This query needs only one reply, so stop immediately.

$self->{bus}->onMessageReceived->remove($self->{receivedEvent});

delete $self->{receivedEvent};

$self->{state} = DONE;

}

}

}

1;