#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;
use Carp;
use Parse::CSV;
use SNMP;
use SNMP::Effective;


#---------------------------------------------------------

my $csv_file = shift || die "Please specify a CSV file with SNMP host info!";

my @reqired_fields = qw(HOSTIP COMMUNITY SNMPVER SNMPPORT);
my @hosts = read_hosts_csv($csv_file, @reqired_fields);


# This object encapsulates the desired queries to run.
my $query = SNMP::Effective->new(
    max_sessions   => 50,
    #master_timeout => $TIMEOUT_SECONDS,
);

my @results;
foreach my $host (@hosts) {

    my @varbinds = qw(
           ifDescr ifInOctets ifOutOctets ifAlias ifType
           ifName ifInErrors ifOutErrors ifSpeed
           ifAdminStatus ifOperStatus
    );

    my $callback = sub {
        my $host_obj  = shift; # SNMP::Effective::Host object
        my $error     = shift; # Error message.
        if ($error) {
            warn $error;
            return;
        }
        push @results, [ $host_obj->address(), $host_obj->data() ];
    };

    $query->add(
        dest_host => $host->{HOSTIP},
        callback  => $callback,
        walk      => [ @varbinds ],
        arg       => {
            Community  => $host->{COMMUNITY},
            Version    => $host->{SNMPVER},
            RemotePort => $host->{SNMPPORT},
        },
    );

}

# Run all the added queries with up to X
# asynchronous operations in-flight at any time.
foreach my $iter (1..1) {
    sleep 30 unless $iter == 1;
    $query->execute();
    print Dumper \@results;
}


exit;
#---------------------------------------------------------

# Read in the CSV file.
sub read_hosts_csv {
    my $file = shift;
    my @required_fields = @_;

    # Parse entries from a CSV file into hashes hash
    my $csv_parser = Parse::CSV->new(
        file   => $file,
        fields => 'auto',  # Use the first line as column headers,
                           # which become the hash keys.
    );

    my @node_cfg; # Return a reference to this
    my $line_num = 0;
    while ( my $line = $csv_parser->fetch() ) {
        $line_num++;
        my $error_flag = 0;
        foreach my $field (@required_fields) {
            if ( ! exists $line->{$field} ) {
                $error_flag = 1;
                carp "Missing field [$field] on line [$line_num] in CSV file [$file]";
            }
        }
        croak "Terminating due to errors on line [$line_num] in CSV file [$file]"
            if $error_flag;

        push @node_cfg, $line;
    }

    if ( $csv_parser->errstr() ) {
        croak "Fatal error parsing [$file]: " . $csv_parser->errstr();
    }

    return @node_cfg;
}


1;
__END__