#!/usr/bin/perl -w

use File::Basename;
use Getopt::Long;
use Amazon::SQS::Simple;

my %opts;
GetOptions(
    \%opts, 
    'flush', 
    'timeout=i', 
    'help', 
    'delete', 
    'create', 
    'info', 
    'access-key', 
    'secret-key',
    'list-queues',
    'verbose',
);

my $scr             = basename($0);
my $queue_name      = shift;

my $AWSAccessKeyId  = $opts{'access-key'} || $ENV{AWS_ACCESS_KEY}; 
my $SecretKey       = $opts{'secret-key'} || $ENV{AWS_SECRET_KEY};

usage(0) if ($opts{help});
usage(1) if @ARGV;

sub usage {
    my $status = shift || 0;
    print <<USAGE;
Usage: 
    $scr --list-queues
    $scr [OPTIONS] queue-name

OPTIONS:
    --flush
        remove all visible messages from queue

    --timeout=SECS
        set the queue's default visibility timeout in seconds

    --create
        create a queue with the given name

    --delete
        delete the queue with the given name

    --info
        print info about the queue

    --help
        show this help documentation

    --verbose
        make output of some operations more verbose

    --access-key=KEY
        Your AWS access key (or set AWS_ACCESS_KEY env 
        variable)

    --secret-key=KEY
        Your AWS secret key (or set AWS_SECRET_KEY env
        variable)
USAGE

    exit($status);
}

use strict;

my $sqs = new Amazon::SQS::Simple($AWSAccessKeyId, $SecretKey);
my $q;

if ($opts{'list-queues'}) {
    my $queues = $sqs->ListQueues();
    if ($queues) {
        foreach my $queue (@$queues) {
            (my $name = $queue->Endpoint()) =~ s|.*/||;
            printf ("%s (Endpoint: %s)\n", $name, $queue->Endpoint());
        }
    }
    else {
        print "You don't have any queues (use --create to create one)"
    }
    exit(0);
}

usage(1) unless $queue_name;

if ($opts{create}) {
    $q = q_create($queue_name);
}
else {
    $q = q_find($queue_name);
}

if ($opts{timeout}) {
    q_timeout($q, $opts{timeout});
}

if ($opts{info}) {
    q_info($q);
}

if ($opts{flush}) {
    q_flush($q);
}

if ($opts{delete}) {
    q_delete($q);
}

sub q_find {
    my $name = shift;
    my $queues = $sqs->ListQueues(QueueNamePrefix => $name);
    if ($queues) {
        my @matches = grep { $_->Endpoint() =~ m|/$name$|} @$queues;
        if (@matches > 1) {
            warn "[WARNING] Multiple queues found with name $name\n";
        }
        if (@matches) {
            return $matches[0];
        }
    }
    die "No queue called $name found (try using --list-queues)\n";
}

sub q_create {
    my $name = shift;
    $sqs->CreateQueue($name);
}

sub q_delete {
    my $queue = shift;
    my $href = $queue->Delete();
}

sub q_info {
    my $queue = shift;
    print "Endpoint: $queue\nAttributes:\n";
    my $attrs = $queue->GetAttributes();
    for (keys %$attrs) {
        print "$_ => $attrs->{$_}\n";
    }
}

sub q_flush {
    my $queue = shift;
    while (my $msg = $queue->ReceiveMessage) {
        if ($opts{verbose}) {
            print "Deleting " . $msg->MessageId . "\n";
        }
        $queue->DeleteMessage($msg->ReceiptHandle);
    }
}

sub q_timeout {
    my $queue = shift;
    my $t = shift;

    if (defined $t) { 
        $queue->SetAttribute('VisibilityTimeout', $t);
    }
    else {
        my $href = $queue->GetAttributes();
        return $href->{VisibilityTimeout};
    }
}