File Coverage

blib/lib/Device/Gsm.pm

Criterion	Covered	Total	%
statement	24	507	4.7
branch	0	200	0.0
condition	0	99	0.0
subroutine	8	35	22.8
pod	19	24	79.1
total	51	865	5.9

# Device::Gsm - a Perl class to interface GSM devices as AT modems
# Copyright (C) 2002-2016 Cosimo Streppone, [e-mail]
# Copyright (C) 2006-2015 Grzegorz Wozniak, [e-mail]
# Copyright (C) 2016 Joel Maslak, [e-mail]

# This program is free software; you can redistribute it and/or modify
# it only under the terms of Perl itself.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# Perl licensing terms for more details.

package Device::Gsm;

$Device::Gsm::VERSION = '1.61';

use strict;
use Device::Modem 1.47;
use Device::Gsm::Sms;
use Device::Gsm::Pdu;
use Device::Gsm::Charset;
use Device::Gsm::Sms::Token;
use Time::HiRes qw(sleep);
use constant USSD_DCS => 15;

@Device::Gsm::ISA = ('Device::Modem');

%Device::Gsm::USSD_RESPONSE_CODES = (
    0 =>
        'No further user action required (network initiated USSD-Notify, or no further information needed after mobile Initiated operation)',
    1 =>
        'Further user action required (network initiated USSD-Request, or  further information needed after mobile initiated operation)',
    2 =>
        'USSD terminated by network. the reason for the termination is indicated  by the index stored in %Device::Gsm::USSD_TERMINATION_CODES',
    3 => 'Other local client has responded',
    4 => 'Operation not supported',
    5 => 'Network time out'
);
%Device::Gsm::USSD_TERMINATION_CODES = (
    0  => 'NO_CAUSE',
    1  => 'CC_BUSY',
    2  => 'PARAMETER_ERROR',
    3  => 'INVALID_NUMBER',
    4  => 'OUTGOING_CALL_BARRED',
    5  => 'TOO_MANY_CALLS_ON_HOLD',
    6  => 'NORMAL',
    10 => 'DROPPED',
    12 => 'NETWORK',
    13 => 'INVALID_CALL_ID',
    14 => 'NORMAL_CLEARING',
    16 => 'TOO_MANY_ACTIVE_CALLS',
    17 => 'UNASSIGNED_NUMBER',
    18 => 'NO_ROUTE_TO_DEST',
    19 => 'RESOURCE_UNAVAILABLE',
    20 => 'CALL_BARRED',
    21 => 'USER_BUSY',
    22 => 'NO_ANSWER',
    23 => 'CALL_REJECTED',
    24 => 'NUMBER_CHANGED',
    25 => 'DEST_OUT_OF_ORDER',
    26 => 'SIGNALING_ERROR',
    27 => 'NETWORK_ERROR',
    28 => 'NETWORK_BUSY',
    29 => 'NOT_SUBSCRIBED',
    31 => 'SERVICE_UNAVAILABLE',
    32 => 'SERVICE_NOT_SUPPORTED',
    33 => 'PREPAY_LIMIT_REACHED',
    35 => 'INCOMPATIBLE_DEST',
    43 => 'ACCESS_DENIED',
    45 => 'FEATURE_NOT_AVAILABLE',
    46 => 'WRONG_CALL_STATE',
    47 => 'SIGNALING_TIMEOUT',
    48 => 'MAX_MPTY_PARTICIPANTS_EXCEEDED',
    49 => 'SYSTEM_FAILURE',
    50 => 'DATA_MISSING',
    51 => 'BASIC_SERVICE_NOT_PROVISIONED',
    52 => 'ILLEGAL_SS_OPERATION',
    53 => 'SS_INCOMPATIBILITY',
    54 => 'SS_NOT_AVAILABLE',
    55 => 'SS_SUBSCRIPTION_VIOLATION',
    56 => 'INCORRECT_PASSWORD',
    57 => 'TOO_MANY_PASSWORD_ATTEMPTS',
    58 => 'PASSWORD_REGISTRATION_FAILURE',
    59 => 'ILLEGAL_EQUIPMENT',
    60 => 'UNKNOWN_SUBSCRIBER',
    61 => 'ILLEGAL_SUBSCRIBER',
    62 => 'ABSENT_SUBSCRIBER',
    63 => 'USSD_BUSY',
    65 => 'CANNOT_TRANSFER_MPTY_CALL',
    66 => 'BUSY_WITH_UNANSWERED_CALL',
    68 => 'UNANSWERED_CALL_PENDING',
    69 => 'USSD_CANCELED',
    70 => 'PRE_EMPTION',
    71 => 'OPERATION_NOT_ALLOWED',
    72 => 'NO_FREE_BEARER_AVAILABLE',
    73 => 'NBR_SN_EXCEEDED',
    74 => 'NBR_USER_EXCEEDED',
    75 => 'NOT_ALLOWED_BY_CC',
    76 => 'MODIFIED_TO_SS_BY_CC',
    77 => 'MODIFIED_TO_CALL_BY_CC',
    78 => 'CALL_MODIFIED_BY_CC',
    90 => 'FDN_FAILURE'
);

# Connection defaults to 19200 baud. This seems to be the optimal
# rate for serial links to new gsm phones.
$Device::Gsm::BAUDRATE = 19200;

# Time to wait after network register command (secs)
$Device::Gsm::REGISTER_DELAY = 2;

# Connect on serial port to gsm device
# see parameters on Device::Modem::connect()
sub connect {
    my $me = shift;
    my %aOpt;
    %aOpt = @_ if (@_);

    #
    # If you have problems with bad characters being trasmitted across serial link,
    # try different baud rates, as below...
    #
    # .---------------------------------.
    # | Model (phone/modem) |  Baudrate |
    # |---------------------+-----------|
    # | Falcom Swing (A2D)  |      9600 |
    # | Siemens C35/C45     |     19200 |
    # | Nokia phones        |     19200 |
    # | Nokia Communicator  |      9600 |
    # | Digicom             |      9600 |
    # `---------------------------------'
    #
    # GSM class defaults to 19200 baud
    #
    $aOpt{'baudrate'} ||= $Device::Gsm::BAUDRATE;

    $me->{_test_cache} = {}; # We clear the list of commands supported,
                             # in case the user disconnects one phone
                             # and connects a different kind of phone

    $me->SUPER::connect(%aOpt);
}

sub disconnect {
    my $me = shift;
    $me->{_test_cache} = {}; # Not strictly needed, but this is safety code
    $me->SUPER::disconnect();
    sleep 0.05;
}

#
# Get/set phone date and time
#
sub datetime {
    my $self     = shift;
    my $ok       = undef;    # ok/err flag
    my $datetime = undef;    # datetime string
    my @time     = ();       # array in "localtime" format

    # Test support for clock function
    if ($self->test_command('+CCLK')) {

        if (@_) {

            # If called with "$self->datetime(time())" format
            if (@_ == 1) {

                # $_[0] must be result of `time()' func
                @time = localtime($_[0]);
            }
            else {

                # If called with "$self->datetime(localtime())" format
                # @_ here is the result of `localtime()' func
                @time = @_;
            }

            $datetime = sprintf(
                '%02d/%02d/%02d,%02d:%02d:%02d',
                $time[5] - 100,    # year
                1 + $time[4],      # month
                $time[3],          # day
                @time[ 2, 1, 0 ],  # hr,min,secs
            );

            # Set time of phone
            $self->atsend(qq{AT+CCLK="$datetime"} . Device::Modem::CR);
            $ok = $self->parse_answer($Device::Modem::STD_RESPONSE);

            $self->log->write(
                'info',
                "write datetime ($datetime) to phone => ("
                    . ($ok ? 'OK' : 'FAILED') . ")"
            );

        }
        else {

            $self->atsend('AT+CCLK?' . Device::Modem::CR);
            ($ok, $datetime)
                = $self->parse_answer($Device::Modem::STD_RESPONSE);

            #warn('datetime='.$datetime);
            if (   $ok
                && $datetime
                =~ m|\+CCLK:\s*"?(\d\d)/(\d\d)/(\d\d)\,(\d\d):(\d\d):(\d\d)"?|
                )
            {
                $datetime = "$1/$2/$3 $4:$5:$6";
                $self->log->write(
                    'info',
                    "read datetime from phone ($datetime)"
                );
            }
            else {
                $self->log->write(
                    'warn',
                    "datetime format ($datetime) not recognized"
                );
                $datetime = undef;
            }

        }

    }

    return $datetime;

}

#
# Delete a message from sim card
#
sub delete_sms {
    my $self      = shift;
    my $msg_index = shift;
    my $storage   = shift;
    my $ok;

    if (!defined $msg_index || $msg_index eq '') {
        $self->log->write(
            'warn',
            'undefined message number. cannot delete sms message'
        );
        return 0;
    }

    # Set default SMS storage if supported
    $self->storage($storage);

    $self->atsend(qq{AT+CMGD=$msg_index} . Device::Modem::CR);

    my $ans = $self->parse_answer($Device::Modem::STD_RESPONSE);
    if (index($ans, 'OK') > -1 || $ans =~ /\+CMGD/) {
        $ok = 1;
    }

    $self->log->write(
        'info',
        "deleting sms n.$msg_index from storage "
            . ($storage || "default")
            . " (result: `$ans') => "
            . ($ok ? 'ok' : '*FAILED*')
    );

    return $ok;
}

#
# Call forwarding
#
sub forward {
    my ($self, $reason, $mode, $number) = @_;

    $reason = lc $reason || 'unconditional';
    $mode   = lc $mode   || 'register';
    $number ||= '';

    my %reasons = (
        'unconditional' => 0,
        'busy'          => 1,
        'no reply'      => 2,
        'unreachable'   => 3
    );

    my %modes = (
        'disable'  => 0,
        'enable'   => 1,
        'query'    => 2,
        'register' => 3,
        'erase'    => 4
    );

    my $reasoncode = $reasons{$reason};
    my $modecode   = $modes{$mode};

    $self->log->write(
        'info',
        qq{setting $reason call forwarding to [$number]}
    );
    $self->atsend(
        qq{AT+CCFC=$reasoncode,$modecode,"$number"} . Device::Modem::CR);

    return $self->parse_answer($Device::Modem::STD_RESPONSE, 15000);
}

#
# Hangup and terminate active call(s)
# this overrides the `Device::Modem::hangup()' method
#
sub hangup {
    my $self = shift;
    $self->log->write('info', 'hanging up...');
    $self->attention();
    $self->atsend('AT+CHUP' . Device::Modem::CR);
    $self->flag('OFFHOOK', 0);
    $self->answer(undef, 5000);
}

#
# Who is the manufacturer of this device?
#
sub manufacturer {
    my $self = shift;
    my ($ok, $man);

    # We can't test for command support, because some phones, mainly Motorola
    # will spit out an error, instead of telling if CGMI is supported.
    $self->atsend('AT+CGMI' . Device::Modem::CR);
    ($ok, $man) = $self->parse_answer($Device::Modem::STD_RESPONSE);

    if ($ok ne 'OK') {
        $self->log->write(
            'warn',
            'manufacturer command ended with error [' . $ok . $man . ']'
        );
        return undef;
    }

    # Again, seems that Motorola phones will re-echo
    # the CGMI command header, instead of giving us the
    # manufacturer info we want. Thanks to Niolay Shaplov
    # for reporting (RT #31540)
    if ($man =~ /\+CGMI:\ \"(.*)\"/s) {
        $man = $1;
    }

    $self->log->write(
        'info',
        'manufacturer of this device appears to be [' . $man . ']'
    );

    return $man || $ok;
}

#
# Set text or pdu mode for gsm devices. If no parameter passed, returns current mode
#
sub mode {
    my $self = shift;

    if (@_) {
        my $mode = lc $_[0];
        if ($mode eq 'text') {
            $mode = 1;
        }
        else {
            $mode = 0;
        }
        $self->{'_mode'} = $mode ? 'text' : 'pdu';
        $self->log->write(
            'info',
            'setting mode to [' . $self->{'_mode'} . ']'
        );
        $self->atsend(qq{AT+CMGF=$mode} . Device::Modem::CR);

        return $self->parse_answer($Device::Modem::STD_RESPONSE);
    }

    return ($self->{'_mode'} || '');

}

#
# What is the model of this device?
#
sub model {
    my $self = shift;
    my ($code, $model);

    # Test if manufacturer code command is supported
    if ($self->test_command('+CGMM')) {

        $self->atsend('AT+CGMM' . Device::Modem::CR);
        ($code, $model) = $self->parse_answer($Device::Modem::STD_RESPONSE);

        $self->log->write(
            'info',
            'model of this device is [' . ($model || '') . ']'
        );

    }

    return $model || $code;
}

#
# Get handphone serial number (IMEI number)
#
sub imei {
    my $self = shift;
    my ($code, $imei);

    # Test if manufacturer code command is supported
    if ($self->test_command('+CGSN')) {

        $self->atsend('AT+CGSN' . Device::Modem::CR);
        ($code, $imei) = $self->parse_answer($Device::Modem::STD_RESPONSE);

        $self->log->write('info', 'IMEI code is [' . $imei . ']');

    }
    return $imei || $code;
}

# Alias for `imei()' is `serial_number()'
*serial_number = *imei;

#
# Get mobile phone signal quality (expressed in dBm)
#
sub signal_quality {
    my $self = shift;

    # Error code, dBm (signal power), bit error rate
    my ($code, @dBm, $dBm, $ber);

    # Test if signal quality command is implemented
    if ($self->test_command('+CSQ')) {

        $self->atsend('AT+CSQ' . Device::Modem::CR);
        ($code, @dBm)
            = $self->parse_answer($Device::Modem::STD_RESPONSE, 15000);

        # Vodafone data cards send out response to commands with
        # many empty lines in between, so +CSQ response is not the very
        # first line of answer.
        for (@dBm) {
            if (/\+CSQ:/) {
                $dBm = $_;
                last;
            }
        }

        # Some gsm software send CSQ command result as "+CSQ: xx,yy"
        if ($dBm =~ /\+CSQ:\s*(\d+),(\d+)/) {

            ($dBm, $ber) = ($1, $2);

            # Further process dBm number to obtain real dB power
            if ($dBm > 30) {
                $dBm = -51;
            }
            else {
                $dBm = -113 + ($dBm << 1);
            }

            $self->log->write(
                'info',
                'signal dBm power is ['
                    . $dBm
                    . '], bit error rate ['
                    . $ber . ']'
            );

            # Other versions put out "+CSQ: xx" only...
        }
        elsif ($dBm =~ /\+CSQ:\s*(\d+)/) {

            $dBm = $1;

            $self->log->write('info', 'signal is [' . $dBm . '] "bars"');

        }
        else {

            $self->log->write('warn', 'cannot obtain signal dBm power');

        }

    }
    else {

        $self->log->write('warn', 'signal quality command not supported!');

    }

    return $dBm;

}

#
# Get the GSM software version on this device
#
sub software_version {
    my $self = shift;
    my ($code, $ver);

    # Test if manufacturer code command is supported
    if ($self->test_command('+CGMR')) {

        $self->atsend('AT+CGMR' . Device::Modem::CR);
        ($code, $ver) = $self->parse_answer($Device::Modem::STD_RESPONSE);

        $self->log->write('info', 'GSM version is [' . $ver . ']');

    }

    return $ver || $code;
}

#
# Test support for a specific command
#
sub test_command {
    my ($self, $command) = @_;

    if (!exists($self->{_test_cache})) { $self->{_test_cache} = {} }
    if (exists($self->{_test_cache}{$command})) {
        return $self->{_test_cache}{$command};
    }

    # Support old code adding a `+' if not specified
    # TODO to be removed in 1.30 ?
    if ($command =~ /^[a-zA-Z]/) {
        $command = '+' . $command;
    }

    # Standard test procedure for every command
    $self->log->write(
        'info',
        'testing support for command [' . $command . ']'
    );
    $self->atsend("AT$command=?" . Device::Modem::CR);

    # If answer is ok, command is supported
    my $ok = ($self->answer($Device::Modem::STD_RESPONSE) || '') =~ /OK/o;
    $self->log->write(
        'info',
        'command [' . $command . '] is ' . ($ok ? '' : 'not ') . 'supported'
    );

    $self->{_test_cache}{$command} = $ok;
    return $ok;
}

#
# Read all messages on SIM card (XXX must be registered on network)
#
sub messages {
    my ($self, $storage) = @_;
    my @messages;

    # By default (old behaviour) messages are read from sim card
    $storage ||= 'SM';

    $self->log->write('info', 'Reading messages on '
            . ($storage eq 'SM' ? 'Sim card' : 'phone memory'));

    # Register on network (give your PIN number for this!)
    #return undef unless $self->register();
    $self->register();

    #
    # Read messages (TODO need to check if device supports CMGL with `stat'=4)
    #
    if ($self->mode() eq 'text') {
        warn 'Read messages in text mode is not implemented yet.';

        #@messages = $self->_read_messages_text();
    }
    else {

        # Set default storage if supported
        $self->storage($storage);

        push @messages, $self->_read_messages_pdu();
    }

    return @messages;
}

sub storage {
    my $self = shift;
    my $ok   = 0;

    # Set default SMS storage if supported by phone
    if (@_ && (my $storage = uc $_[0])) {
        return unless $self->test_command('+CPMS');
        $self->atsend(qq{AT+CPMS="$storage"} . Device::Modem::CR);

        # Read and discard the answer
        $self->answer($Device::Modem::STD_RESPONSE, 5000);
        $self->{_storage} = $storage;
    }

    return $self->{_storage};
}

#
# Register to GSM service provider network
#
sub register {
    my $me  = shift;
    my $lOk = 0;

    # Check for connection
    if (!$me->{'CONNECTED'}) {
        $me->log->write('info', 'Not yet connected. Doing it now...');
        if (!$me->connect()) {
            $me->log->write('warning', 'No connection!');
            return $lOk;
        }
    }

    # On some phones, registration doesn't work, so you can skip it entirely
    # by passing 'assume_registered => 1' to the new() constructor
    if (exists $me->{'assume_registered'} && $me->{'assume_registered'}) {
        return $me->{'REGISTERED'} = 1;
    }

    # Send PIN status query
    $me->log->write('info', 'PIN status query');
    $me->atsend('AT+CPIN?' . Device::Modem::CR);

    # Get answer
    my $cReply = $me->answer($Device::Modem::STD_RESPONSE, 10000);

    if (!defined $cReply || $cReply eq "") {
        $me->log->write('warn',
            'Could not get a reply for the AT+CPIN command');
        return;
    }

    if ($cReply =~ /(READY|SIM PIN2)/) {

        # Iridium satellite phones rest saying "SIM PIN2" when they are registered...

        $me->log->write(
            'info',
            'Already registered on network. Ready to send.'
        );
        $lOk = 1;

    }
    elsif ($cReply =~ /SIM PIN/) {

        # Pin request, sending PIN code
        $me->log->write('info', 'PIN requested: sending...');
        $me->atsend(qq[AT+CPIN="$$me{'pin'}"] . Device::Modem::CR);

        # Get reply
        $cReply = $me->answer($Device::Modem::STD_RESPONSE, 10000);

        # Test reply
        if ($cReply !~ /ERROR/) {
            $me->log->write('info', 'PIN accepted. Ready to send.');
            $lOk = 1;
        }
        else {
            $me->log->write('warning', 'PIN rejected');
            $lOk = 0;
        }

    }

    # Store status in object and return
    $me->{'REGISTERED'} = $lOk;

    return $lOk;
}

# send_sms( %options )
#
#   recipient => '[phone]'
#   class     => 'flash' | 'normal'
#   validity  => [ default = 24 hours ]
#   content   => 'text-only for now'
#   mode      => 'text' | 'pdu'        (default = 'pdu')
#
sub send_sms {

    my ($me, %opt) = @_;

    my $lOk = 0;
    my $mr;
    return unless $opt{'recipient'} and $opt{'content'};

    # Check if registered to network
    if (!$me->{'REGISTERED'}) {
        $me->log->write('info', 'Not yet registered, doing now...');
        $me->register();

        # Wait some time to allow SIM registering to network
        $me->wait($Device::Gsm::REGISTER_DELAY << 10);
    }

    # Again check if now registered
    if (!$me->{'REGISTERED'}) {

        $me->log->write('warning', 'ERROR in registering to network');
        return $lOk;

    }

    # Ok, registered. Select mode to send SMS
    $opt{'mode'} ||= 'PDU';
    if (uc $opt{'mode'} ne 'TEXT') {

        ($lOk, $mr) = $me->_send_sms_pdu(%opt);

    }
    else {

        ($lOk, $mr) = $me->_send_sms_text(%opt);
    }

    # Return result of sending
    return wantarray ? ($lOk, $mr) : $lOk;
}

# send_csms( %options )
#
#   recipient => '[phone]'
#   class     => 'flash' | 'normal'
#   validity  => [ default = 24 hours ]
#   content   => 'text-only above 160 chars'
#
sub send_csms {

    my ($me, %opt) = @_;

    my $lOk = 0;
    my @mrs;
    return unless $opt{'recipient'} and $opt{'content'};

    # Check if registered to network
    if (!$me->{'REGISTERED'}) {
        $me->log->write('info', 'Not yet registered, doing now...');
        $me->register();

        # Wait some time to allow SIM registering to network
        $me->wait($Device::Gsm::REGISTER_DELAY << 10);
    }

    # Again check if now registered
    if (!$me->{'REGISTERED'}) {

        $me->log->write('warning', 'ERROR in registering to network');
        return 0;

    }

    # Ok, registered. Select mode to send SMS
    $opt{'mode'} ||= 'PDU';

    if (uc $opt{'mode'} eq 'TEXT') {
        $me->log->write('warning', 'CSMS only in PDU mode, switching');
        until (uc($me->{'_mode'}) ne 'PDU') {
            $me->mode('pdu') or sleep 0.05;
        }
    }
    my @text_parts;

    #ensure we have to send CSMS
    if (Device::Gsm::Charset::gsm0338_length($opt{'content'}) <= 160) {
        my @send_return = $me->_send_sms_pdu(%opt);
        if ($send_return[0]) {
            $lOk++;
            push(@mrs, $send_return[1]);
        }
        else {
            $lOk  = 0;
            $#mrs = -1;
        }
    }
    else {
        my $udh        = new Sms::Token("UDH");
        my $ref_num    = sprintf("%02X", (int(rand(255))));
        my @text_parts = Device::Gsm::Charset::gsm0338_split($opt{'content'});
        my $parts      = scalar(@text_parts);
        $parts = sprintf("%02X", $parts);
        my $padding
            = Sms::Token::UDH::calculate_padding(Sms::Token::UDH::IEI_T_8_L);
        my $part_count = 1;
        foreach my $text_part (@text_parts) {
            my $part = sprintf("%02X", $part_count);
            my ($len_hex, $encoded_text)
                = Device::Gsm::Pdu::encode_text7_udh($text_part, $padding);
            $part_count++;
            $opt{'content'} = $text_part;
            $opt{'pdu_msg'}
                = sprintf("%02X",
                hex($len_hex) + Sms::Token::UDH::IEI_T_8_L + 2)
                . $udh->encode(
                Sms::Token::UDH::IEI_T_8 => $ref_num . $parts . $part)
                . $encoded_text;
            my @send_return = $me->send_sms_pdu_long(%opt);
            if ($send_return[0]) {
                $lOk++;
                push(@mrs, $send_return[1]);

            }
            else {
                $lOk  = 0;
                $#mrs = -1;
                last;
            }
            sleep 0.05;
        }
    }

    # Return result of sending
    return wantarray ? ($lOk, @mrs) : $lOk;
}

#
#
# read messages in pdu mode
#
#
sub _read_messages_pdu {
    my $self = shift;

    $self->mode('pdu');

    $self->atsend(q{AT+CMGL=4} . Device::Modem::CR);
    my ($messages) = $self->answer($Device::Modem::STD_RESPONSE, 5000);

    # Catch the case that the msgs are returned with gaps between them
    while (my $more = $self->answer($Device::Modem::STD_RESPONSE, 200)) {

        #-- $self->answer will chomp trailing newline, add it back
        $messages .= "\n";
        $messages .= $more;
    }

    # Ok, messages read, now convert from PDU and store in object
    $self->log->write('debug', 'Messages=' . $messages);

    my @data = split /[\r\n]+/m, $messages;

    # Check for errors on SMS reading
    my $code;
    if (($code = pop @data) =~ /ERROR/) {
        $self->log->write(
            'error',
            'cannot read SMS messages on SIM: [' . $code . ']'
        );
        return ();
    }

    my @message = ();
    my $current;

    # Current sms storage memory (ME or SM)
    my $storage = $self->storage();

    #
    # Parse received data (result of +CMGL command)
    #
    while (@data) {

        $self->log->write('debug', 'data[] = ', $data[0]);
        my $header = shift @data;
        my $pdu    = shift @data;

        # Instance new message object
        my $msg = new Device::Gsm::Sms(
            header => $header,
            pdu    => $pdu,

            # XXX mode   => $self->mode(),
            storage => $storage,
            parent  => $self       # Ref to parent Device::Gsm class
        );

        # Check if message has been instanced correctly
        if (ref $msg) {
            push @message, $msg;
        }
        else {
            $self->log->write(
                'info',
                "could not instance message $header $pdu!"
            );
        }

    }

    $self->log->write(
        'info',
        'found ' . (scalar @message) . ' messages on SIM. Reading.'
    );

    return @message;

}

#
# _send_sms_text( %options ) : sends message in text mode
#
sub _send_sms_text {
    my ($me, %opt) = @_;

    my $num  = $opt{'recipient'};
    my $text = $opt{'content'};

    return 0 unless $num and $text;

    my $lOk = 0;
    my $mr;
    my $cReply;

    # Select text format for messages
    $me->mode('text');
    $me->log->write('info', 'Selected text format for message sending');

    # Send sms in text mode
    $me->atsend(qq[AT+CMGS="$num"] . Device::Modem::CR);

    # Wait a bit before sending the text. Some GSM software needs it.
    $me->wait($Device::Modem::WAITCMD);

    # Complete message sending
    $text = Device::Gsm::Charset::iso8859_to_gsm0338($text);
    $me->atsend($text . Device::Modem::CTRL_Z);

    # Get reply and check for errors
    $cReply = $me->answer('+CMGS', 2000);
    if ($cReply =~ /OK$/i) {
        $cReply =~ /\+CMGS:\s*(\d+)/i;
        $me->log->write('info', "Sent SMS (text mode) to $num!");
        $lOk = 1;
        $mr  = $1;
    }
    else {
        $me->log->write('warning', "ERROR in sending SMS");
    }

    return wantarray ? ($lOk, $mr) : $lOk;
}

#
# _send_sms_pdu( %options )  : sends message in PDU mode
#
sub _send_sms_pdu {
    my ($me, %opt, $is_gsm0338) = @_;

    # Get options
    my $num  = $opt{'recipient'};
    my $text = $opt{'content'};

    return 0 unless $num and $text;

    $me->atsend(q[ATE1] . Device::Modem::CR);
    $me->answer($Device::Modem::STD_RESPONSE);

    # Select class of sms (normal or *flash sms*)
    my $class = $opt{'class'} || 'normal';
    $class = $class eq 'normal' ? '00' : 'F0';

    #Validity period value
    #0 to 143	(TP-VP + 1) * 5 minutes (i.e. 5 minutes intervals up to 12 hours)
    #144 to 167	12 hours + ((TP-VP - 143) * 30 minutes)
    #168 to 196	(TP-VP - 166) * 1 day
    #197 to 255	(TP-VP - 192) * 1 week
    #default 24h
    my $vp = 'A7';
    if (defined $opt{'validity_period'}) {
        $vp = sprintf("%02X", $opt{'validity_period'});
    }

    # Status report requested?
    my $status_report = 0;
    if (exists $opt{'status_report'} && $opt{'status_report'}) {
        $status_report = 1;
    }

    my $lOk = 0;
    my $mr  = undef;
    my $cReply;

    # Send sms in PDU mode

    #
    # Example of sms send in PDU mode
    #
    #AT+CMGS=22
    #> 0011000A8123988277190000AA0AE8329BFD4697D9EC37
    #+CMGS: 111
    #
    #OK

    # Encode DA
    my $enc_da = Device::Gsm::Pdu::encode_address($num);
    $me->log->write('info', 'encoded dest. address is [' . $enc_da . ']');

    # Encode text
    $is_gsm0338 or $text = Device::Gsm::Charset::iso8859_to_gsm0338($text);
    my $enc_msg = Device::Gsm::Pdu::encode_text7($text);
    $me->log->write(
        'info',
        'encoded 7bit text (w/length) is [' . $enc_msg . ']'
    );

    # Build PDU data
    my $pdu = uc join(
        '',
        '00',
        ($status_report ? '31' : '11'),
        '00',
        $enc_da,
        '00',
        $class,
        $vp,
        $enc_msg
    );

    $me->log->write('info', 'due to send PDU [' . $pdu . ']');

    # Sending main SMS command ( with length )
    my $len = ((length $pdu) >> 1) - 1;

    #$me->log->write('info', 'AT+CMGS='.$len.' string sent');

    # Select PDU format for messages
    $me->atsend(q[AT+CMGF=0] . Device::Modem::CR);
    $me->answer($Device::Modem::STD_RESPONSE);
    $me->log->write('info', 'Selected PDU format for msg sending');

    # Send SMS length
    $me->atsend(qq[AT+CMGS=$len] . Device::Modem::CR);
    $me->answer($Device::Modem::STD_RESPONSE);

    # Sending SMS content encoded as PDU
    $me->log->write('info', 'PDU sent [' . $pdu . ' + CTRLZ]');
    $me->atsend($pdu . Device::Modem::CTRL_Z);

    # Get reply and check for errors
    $cReply = $me->answer($Device::Modem::STD_RESPONSE, 30000);
    $me->log->write('debug', "SMS reply: $cReply\r\n");

    if ($cReply =~ /OK$/i) {
        $cReply =~ /\+CMGS:\s*(\d+)/i;
        $me->log->write('info', "Sent SMS (pdu mode) to $num!");
        $lOk = 1;
        $mr  = $1;

    }
    else {
        $cReply =~ /(\+CMGS:.*)/;
        $me->log->write('warning', "ERROR in sending SMS: $1");
    }

    return wantarray ? ($lOk, $mr) : $lOk;
}

sub send_sms_pdu_long {
    my ($me, %opt) = @_;

    # Get options
    my $num     = $opt{'recipient'};
    my $text    = $opt{'content'};
    my $pdu_msg = $opt{'pdu_msg'};

    return 0 unless $num and $text and $pdu_msg;

    $me->atsend(q[ATE1] . Device::Modem::CR);
    $me->answer($Device::Modem::STD_RESPONSE);

    # Select class of sms (normal or *flash sms*)
    my $class = $opt{'class'} || 'normal';
    $class = $class eq 'normal' ? '00' : 'F0';

    #Validity period value
    #0 to 143	(TP-VP + 1) * 5 minutes (i.e. 5 minutes intervals up to 12 hours)
    #144 to 167	12 hours + ((TP-VP - 143) * 30 minutes)
    #168 to 196	(TP-VP - 166) * 1 day
    #197 to 255	(TP-VP - 192) * 1 week
    #default 24h
    my $vp = 'A7';
    if (defined $opt{'validity_period'}) {
        $vp = sprintf("%02X", $opt{'validity_period'});
    }

    # Status report requested?
    my $status_report = 0;
    if (exists $opt{'status_report'} && $opt{'status_report'}) {
        $status_report = 1;
    }

    my $lOk = 0;
    my $mr  = undef;
    my $cReply;

    # Send sms in PDU mode

    #
    # Example of sms send in PDU mode
    #
    #AT+CMGS=22
    #> 0011000A8123988277190000AA0AE8329BFD4697D9EC37
    #+CMGS: 111
    #
    #OK

    # Encode DA
    my $enc_da = Device::Gsm::Pdu::encode_address($num);
    $me->log->write('info', 'encoded dest. address is [' . $enc_da . ']');

    # Encode text
    #$text = Device::Gsm::Charset::iso8859_to_gsm0338($text);
    #my $enc_msg = Device::Gsm::Pdu::encode_text7($text);
    $me->log->write(
        'info',
        'encoded 7bit text (w/length) is [' . $pdu_msg . ']'
    );

    # Build PDU data
    my $pdu = uc join(
        '',

        #we use default SMSC address(don supply one)
        '00',

        #as you can see when UDH is present we set 6 bit of of first octet, you can recognize CSM that way, I prefer regex :) (se UD.pm)
        ($status_report ? '71' : '51'),

        #message reference, my G24 returns own MR after successful sending, setting this value did nothing in that case, but other modems may behave differently
        '00',
        $enc_da,

        #protocol identifier (0x00 use default)
        '00',

        # data coding scheme (flash sms or normal, coding etc. more about
	# http://en.wikipedia.org/wiki/Data_Coding_Scheme)
        $class,
        $vp,
        $pdu_msg
    );

    $me->log->write('info', 'due to send PDU [' . $pdu . ']');

    # Sending main SMS command ( with length )
    my $len = ((length $pdu) >> 1) - 1;

    #$me->log->write('info', 'AT+CMGS='.$len.' string sent');

    # Select PDU format for messages
    $me->atsend(q[AT+CMGF=0] . Device::Modem::CR);
    $me->answer($Device::Modem::STD_RESPONSE);
    $me->log->write('info', 'Selected PDU format for msg sending');

    # Send SMS length
    $me->atsend(qq[AT+CMGS=$len] . Device::Modem::CR);
    $me->answer($Device::Modem::STD_RESPONSE);

    # Sending SMS content encoded as PDU
    $me->log->write('info', 'PDU sent [' . $pdu . ' + CTRLZ]');
    $me->atsend($pdu . Device::Modem::CTRL_Z);

    # Get reply and check for errors
    $cReply = $me->answer($Device::Modem::STD_RESPONSE, 30000);
    $me->log->write('debug', "SMS reply: $cReply\r\n");

    if ($cReply =~ /OK$/i) {
        $cReply =~ /\+CMGS:\s*(\d+)/i;
        $me->log->write('info', "Sent SMS (pdu mode) to $num!");
        $lOk = 1;
        $mr  = $1;
    }
    else {
        $cReply =~ /(\+CMGS:.*)/;
        $me->log->write('warning', "ERROR in sending SMS: $1");
    }

    return wantarray ? ($lOk, $mr) : $lOk;
}

#
# Set or request service center number
#
sub service_center {

    my $self = shift;
    my $nCenter;
    my $lOk = 1;
    my $code;

    # If additional parameter is supplied, store new message center number
    if (@_) {
        $nCenter = shift();

        # Remove all non numbers or `+' sign
        $nCenter =~ s/[^0-9+]//g;

        # Send AT command
        $self->atsend(qq[AT+CSCA="$nCenter"] . Device::Modem::CR);

        # Check for modem answer
        $lOk = ($self->answer($Device::Modem::STD_RESPONSE) =~ /OK/);

        if ($lOk) {
            $self->log->write(
                'info',
                'service center number [' . $nCenter . '] stored'
            );
        }
        else {
            $self->log->write(
                'warning',
                'unexpected response for "service_center" command'
            );
        }

    }
    else {

        $self->log->write('info', 'requesting service center number');
        $self->atsend('AT+CSCA?' . Device::Modem::CR);

        # Get answer and check for errors
        ($code, $nCenter) = $self->parse_answer($Device::Modem::STD_RESPONSE);

        if ($code =~ /ERROR/) {
            $self->log->write(
                'warning',
                'error status for "service_center" command'
            );
            $lOk = 0;
        }
        else {

            # $nCenter =~ tr/\r\nA-Z//s;
            $self->log->write(
                'info',
                'service center number is [' . $nCenter . ']'
            );

            # Return service center number
            $lOk = $nCenter;
        }

    }

    # Status flag or service center number
    return $lOk;

}

sub network {
    my $self = $_[0];
    my $network;

    #if( ! $self->test_command('COPS') )
    #{
    #    print 'NO COMMAND';
    #    return undef;
    #}

    $self->atsend('AT+COPS?' . Device::Modem::CR);

    # Parse COPS answer, the 3rd string is the network name
    my $ans = $self->answer();
    if ($ans =~ /"([^"]*)"/) {
        $network = $1;
        $self->log->write('info', 'Received network name [' . $network . ']');
    }
    else {
        $self->log->write('info', 'Received no network name');
    }

    # Try to decode the network name
    require Device::Gsm::Networks;
    my $netname = Device::Gsm::Networks::name($network);
    if (!defined $netname || $netname eq 'unknown') {
        $netname = undef;
    }
    return wantarray
        ? ($netname, $network)
        : $netname;

}

#
#returns simcard MSISDN
#
sub selfnum {
    my $self = shift;
    my @selfnum;
    my $selfnum;
    if ($self->test_command('CNUM')) {
        $self->atsend('AT+CNUM' . Device::Modem::CR);
        my $ans = $self->answer($Device::Modem::STD_RESPONSE);
        my @answer = split /[\r\n]+/m, $ans;
        foreach (@answer) {
            if ($_ =~ /^\+CNUM: /) {
                my @temp = split /,/, $';
                $temp[1] =~ s/"//g;
                if ($temp[1] =~ /\d{9,}/) {
                    !$selfnum and $selfnum = $temp[1];
                    push(@selfnum, $temp[1]);
                }
            }
        }
        if ($selfnum) {
            $self->log->write('info', 'Received number [' . "@selfnum" . ']');
            return wantarray
                ? @selfnum
                : $selfnum;
        }
        else {
            $self->log->write('info', 'Received no numbers');
            return "";
        }

    }

    #
    #On my motorola G24 for messages with alphanumeric sender sender() returns malformed characters
    #on globetrotter option 505 everything is all right. I wrote this at beggining of playng with you module,
    #and almost forgot about it. I'll investigate this bug in future.
    #
}

sub get_literal_header {
    my ($self, $index) = @_;
    my $header = '';

    #set text mode
    $self->atsend('AT+CMGF=1' . Device::Modem::CR);
    sleep 0.05;
    if ($self->answer($Device::Modem::STD_RESPONSE) =~ /OK/) {
        $self->log->write('warning', 'Text mode set');
    }
    else {
        $self->log->write('warning', 'Text mode not set');
        $self->log->write('warning', 'Trying restore PDU mode');
        $self->atsend('AT+CMGF=0' . Device::Modem::CR);
        sleep 0.05;
        $self->answer($Device::Modem::STD_RESPONSE) =~ /OK/
            and $self->log->write('warning', 'PDU mode restored');
        return;
    }
    $self->atsend('AT+MMGR=' . $index . Device::Modem::CR);
    my $ans = $self->answer();
    if ($ans =~ /\+MMGR:/) {
        my @temp = split(/,/, $');
        $header = $temp[1];
        $header =~ s/\"|\'//g;
    }
    $self->atsend('AT+CMGF=0' . Device::Modem::CR);
    sleep 0.05;
    $self->answer($Device::Modem::STD_RESPONSE) =~ /OK/
        and $self->log->write('warning', 'PDU mode Set')
        or return;
    return $header;
}

sub send_ussd {
    my ($self, $message) = @_;
    my $answer  = '';
    my $encoded = Device::Gsm::Pdu::encode_text7_ussd($message);
    if ($self->test_command("CUSD")) {
        my $at_command
            = 'AT+CUSD=1,"' . $encoded . '",' . USSD_DCS . Device::Modem::CR;
        $self->atsend($at_command);
        my $expect     = qr/ERROR|OK|\+CUSD:/;
        my $cReadChars = $Device::Modem::READCHARS;
        $Device::Modem::READCHARS = 300;
        my $response = '';
        $response = $self->answer($expect, 1000);

        # Catch the case that the msgs are returned with gaps between them
        $response =~ m/OK/
            and $response .= "\n" . $self->answer($expect, 15000);
        $Device::Modem::READCHARS = $cReadChars;
        if ($response =~ m/OK/) {
            $self->log->write('warning',
                      'send_ussd command: "'
                    . $message
                    . '" OK, AT: '
                    . $at_command . " "
                    . 'response: '
                    . $response);
            if ($response =~ m/\+CUSD:\s*(\d+)\s*,/) {
                my $response_code = $1;
                $self->log->write('warning',
                    "Have a ussd_response code: $response_code=>"
                        . $Device::Gsm::USSD_RESPONSE_CODES{$1});
                $response = $';
                if ($response_code < 2) {
                    if ($response =~ m/\s*\"?([0-9A-F]+)\"?\s*,\s*(\d*)\s*/) {
                        my $ussd_response = $1;
                        my $ussd_dcs = length($2) ? $2 : USSD_DCS;
                        $self->log->write('warning',
                            "Have a ussd_response message: $ussd_response, dcs: $ussd_dcs"
                        );
                        ($ussd_dcs == 15 or $ussd_dcs == 0)
                            and $answer
                            = Device::Gsm::Pdu::decode_text7_ussd(
                            $ussd_response)
                            and $ussd_dcs = -1;
                        $ussd_dcs == 72
                            and $answer
                            = Device::Gsm::Pdu::decode_text_UCS2(
                            $ussd_response)
                            and $ussd_dcs = -1;
                        $ussd_dcs == 68
                            and $answer
                            = Device::Gsm::Pdu::decode_text8($ussd_response)
                            and $ussd_dcs = -1;
                        $ussd_dcs != -1
                            and $self->log->write('warning',
                            "Cant decode ussd_response message with dcs: $ussd_dcs"
                            );

                    }

                }
                elsif ($response_code == 2) {
                    $response =~ m/\s*(\d+)\s*/
                        and $self->log->write('warning',
                        "Have a ussd_termintion code: $1=>"
                            . $Device::Gsm::USSD_TERMINATION_CODES{$1});
                }
            }
        }
        else {
            $self->log->write('warning',
                      'Error send_ussd command: '
                    . $at_command
                    . ", returned: "
                    . $response);
            return '';

        }
    }
    else {
        $self->log->write('warning',
            'Error send_ussd AT+CUSD command not supported');
        return '';
    }
    return $answer;
}
1;

__END__