package GLPI::Agent::Tools::Linux;

use strict;
use warnings;
use parent 'Exporter';

# Constant for ethtool system call
use constant SIOCETHTOOL   =>     0x8946 ; # See linux/sockios.h
use constant ETHTOOL_GSET  => 0x00000001 ; # See linux/ethtool.h
use constant SPEED_UNKNOWN =>      65535 ; # See linux/ethtool.h, to be read as -1

use English qw(-no_match_vars);
use File::Basename qw(basename dirname);
use Memoize;
use Socket qw(PF_INET SOCK_DGRAM);

use GLPI::Agent::Tools;
use GLPI::Agent::Tools::Unix;
use GLPI::Agent::Tools::Network;

our @EXPORT = qw(
    getDevicesFromUdev
    getDevicesFromHal
    getDevicesFromProc
    getCPUsFromProc
    getInfoFromSmartctl
    getInterfacesFromIfconfig
    getInterfacesFromIp
    getInterfacesInfosFromIoctl
);

memoize('getDevicesFromUdev');

sub getDevicesFromUdev {
    my (%params) = @_;

    my @devices;

    # We need to support dump params to permit full testing when root params is set
    my $root = $params{root} || "";

    foreach my $file (Glob("$root/dev/.udev/db/*")) {
        if ($params{dump} && has_file($file)) {
            my $base = basename($file);
            my $content = getAllLines(file => $file);
            $params{dump}->{dev}->{'.udev'}->{db}->{$base} = $content;
        }
        my $device = getFirstMatch(
            file    => $file,
            pattern => qr/^N:(\S+)/
        );
        next unless $device;
        next unless $device =~ /([hsv]d[a-z]+|sr\d+)$/;
        my $parsed = _parseUdevEntry(
                logger => $params{logger},
                file   => $file,
                device => $device
        );
        push @devices, $parsed if $parsed;
    }

    foreach my $device (@devices) {
        next if $device->{TYPE} && $device->{TYPE} eq 'cd';
        $device->{DISKSIZE} = getDeviceCapacity(
            device => '/dev/' . $device->{NAME},
            %params
        );
    }

    return @devices;
}

sub _parseUdevEntry {
    my (%params) = @_;

    my $handle = getFileHandle(%params);
    return unless $handle;

    my ($result, $serial);
    while (my $line = <$handle>) {
        if ($line =~ /^S:.*-scsi-(\d+):(\d+):(\d+):(\d+)/) {
            $result->{SCSI_COID} = $1;
            $result->{SCSI_CHID} = $2;
            $result->{SCSI_UNID} = $3;
            $result->{SCSI_LUN} = $4;
        } elsif ($line =~ /^E:ID_VENDOR=(.*)/) {
            $result->{MANUFACTURER} = $1;
        } elsif ($line =~ /^E:ID_MODEL=(.*)/) {
            $result->{MODEL} = $1;
        } elsif ($line =~ /^E:ID_REVISION=(.*)/) {
            $result->{FIRMWARE} = $1;
        } elsif ($line =~ /^E:ID_SERIAL=(.*)/) {
            $serial = $1;
        } elsif ($line =~ /^E:ID_SERIAL_SHORT=(.*)/) {
            $result->{SERIALNUMBER} = $1;
        } elsif ($line =~ /^E:ID_TYPE=(.*)/) {
            $result->{TYPE} = $1;
        } elsif ($line =~ /^E:ID_BUS=(.*)/) {
            $result->{DESCRIPTION} = $1;
        }
    }
    close $handle;

    if (!$result->{SERIALNUMBER}) {
        $result->{SERIALNUMBER} = $serial;
    }

    $result->{NAME} = $params{device};

    return $result;
}

sub getCPUsFromProc {
    my (%params) = (
        file => '/proc/cpuinfo',
        @_
    );

    my $handle = getFileHandle(%params);

    my (@cpus, $cpu);

    while (my $line = <$handle>) {
        if ($line =~ /^([^:]+\S) \s* : \s (.+)/x) {
            $cpu->{lc($1)} = trimWhitespace($2);
        } elsif ($line =~ /^$/) {
            # an empty line marks the end of a cpu section
            # push to the list, but only if it is a valid cpu
            push @cpus, $cpu if $cpu && _isValidCPU($cpu);
            undef $cpu;
        }
    }
    close $handle;

    # push remaining cpu to the list, if it is valid cpu
    push @cpus, $cpu if $cpu && _isValidCPU($cpu);

    return @cpus;
}

sub _isValidCPU {
    my ($cpu) = @_;

    return exists $cpu->{processor} || exists $cpu->{cpu};
}


sub getDevicesFromHal {
    my (%params) = (
        command => '/usr/bin/lshal',
        @_
    );

    # We need to support dump params to permit full testing when root params is set
    if ($params{root}) {
        $params{file} = "$params{root}/lshal";
    } elsif ($params{dump}) {
        $params{dump}->{lshal} = getAllLines(%params);
    }

    my $handle = getFileHandle(%params);

    my (@devices, $device);

    while (my $line = <$handle>) {
        chomp $line;
        if ($line =~ m{^udi = '/org/freedesktop/Hal/devices/(storage|legacy_floppy|block)}) {
            $device = {};
            next;
        }

        next unless defined $device;

        if ($line =~ /^$/) {
            push(@devices, $device);
            undef $device;
        } elsif ($line =~ /^\s+ storage.serial \s = \s '([^']+)'/x) {
            $device->{SERIALNUMBER} = $1;
        } elsif ($line =~ /^\s+ storage.firmware_version \s = \s '([^']+)'/x) {
            $device->{FIRMWARE} = $1;
        } elsif ($line =~ /^\s+ block.device \s = \s '([^']+)'/x) {
            my $value = $1;
            ($device->{NAME}) = $value =~ m{/dev/(\S+)};
        } elsif ($line =~ /^\s+ info.vendor \s = \s '([^']+)'/x) {
            $device->{MANUFACTURER} = $1;
        } elsif ($line =~ /^\s+ storage.model \s = \s '([^']+)'/x) {
            $device->{MODEL} = $1;
        } elsif ($line =~ /^\s+ storage.drive_type \s = \s '([^']+)'/x) {
            $device->{TYPE} = $1;
        } elsif ($line =~ /^\s+ storage.size \s = \s (\S+)/x) {
            my $value = $1;
            $device->{DISKSIZE} = int($value/(1024*1024) + 0.5);
        }
    }
    close $handle;

    return @devices;
}

sub getDevicesFromProc {
    my (%params) = @_;

    # We need to support dump params to permit full testing when root params is set
    my $dump   = $params{dump};
    my $root   = $params{root} || "";
    my $logger = $params{logger};

    # compute list of devices
    my @names;

    foreach my $file (Glob("$root/sys/block/*")) {
        if ($dump && has_folder($file)) {
            my $basename = basename($file);
            $dump->{sys}->{block}->{$basename} = {};
        }
        next unless $file =~ /([shv]d[a-z]+|fd\d)$/;
        push @names, $1;
    }

    # add any block device identified as device by the kernel like SSD disks or
    # removable disks (SD cards and others)
    foreach my $file (Glob("$root/sys/block/*/device")) {
        if ($dump && has_folder($file)) {
            my $dirname = basename(dirname($file));
            $dump->{sys}->{block}->{$dirname}->{device} = {};
        }
        next unless $file =~ m|([^/]*)/device$|;
        push @names, $1;
    }

    foreach my $file (Glob("$root/sys/class/scsi_generic/*")) {
        # block devices should have been handled in the previous step
        next if has_folder("$file/device/block/");

        my $basename = basename($file);
        if ($dump && has_folder("$file/device/type")) {
            my $base = $dump->{sys}->{class}->{scsi_generic}->{$basename} = {};
            if (has_file("$file/device/type")) {
                my $content = getAllLines(file => "$file/device/type");
                $base->{device}->{type} = $content;
            }
        }

        my $type = getFirstLine(
            file   => "$file/device/type",
            logger => $logger
        );

        # if not disk
        next if (!defined($type) || $type != 0);

        push @names, $basename;
    }

    # filter duplicates
    my %seen;
    @names = grep { !$seen{$_}++ } @names;

    # filter multipath
    @names = _filterMultipath(names => \@names) if canRun('multipath');

    my $udisksctl = canRun('udisksctl');
    $dump->{udisksctl} = 1 if ($dump && $udisksctl);
    $udisksctl = 1 if $root && has_file("$root/udisksctl");

    # extract information
    my @devices;
    foreach my $name (@names) {
        my $device = {
            NAME         => $name,
            MANUFACTURER => _getValueFromSysProc($logger, $name, 'vendor', $root, $dump),
            MODEL        => _getValueFromSysProc($logger, $name, 'model', $root, $dump),
            FIRMWARE     => _getValueFromSysProc($logger, $name, 'rev', $root, $dump)
                || _getValueFromSysProc($logger, $name, 'firmware_rev', $root, $dump),
            SERIALNUMBER => _getValueFromSysProc($logger, $name, 'serial', $root, $dump)
                || _getValueFromSysProc($logger, $name, 'vpd_pg80', $root, $dump),
            TYPE         =>
                _getValueFromSysProc($logger, $name, 'removable', $root, $dump) ?
                    'removable' : 'disk'
        };

        # WWN
        my $wwn = _getValueFromSysProc($logger, $name, 'wwid', $root, $dump);
        $device->{WWN} = $wwn if $wwn && $wwn =~ s/^naa\./wwn-/;

        # Support PCI or other bus case as description
        foreach my $subsystem ("device/subsystem","device/device/subsystem") {
            my $link = _readLinkFromSysFs("/sys/block/$name/$subsystem", $root, $dump);
            next unless ($link && $link =~ m|^/sys/bus/(\w+)$|);
            $device->{DESCRIPTION} = uc($1);
            last;
        }

        # Support disk size from /sys/block
        my $size_by_sectors = _getValueFromSysProc($logger, $name, 'size', $root, $dump);
        if ($size_by_sectors) {
            $device->{DISKSIZE} = int($size_by_sectors * 512 / 1_000_000);
        }

        # Check removable capacity as HintAuto via udiskctl while available
        if ($udisksctl && $device->{TYPE} eq 'disk') {
            my %match = (
                pattern => qr/^\s+HintAuto:\s+(true|false)$/,
                logger  => $logger
            );
            if ($root) {
                $match{file} = "$root/udisksctl-$name";
            } else {
                $match{command} = "udisksctl info -b /dev/$name";
            }
            $dump->{"udisksctl-$name"} = getAllLines(%match) if ($dump);
            my $hintauto = getFirstMatch(%match);
            $device->{TYPE} = 'removable'
                if ( $hintauto && $hintauto eq 'true' );
        }

        push @devices, $device;
    }

    return @devices;
}

sub _getValueFromSysProc {
    my ($logger, $device, $key, $root, $dump) = @_;

    ## no critic (ExplicitReturnUndef)

    my $file = first { has_file($root.$_) }
        "/sys/block/$device/$key",
        "/sys/block/$device/device/$key",
        "/proc/ide/$device/$key",
        "/sys/class/scsi_generic/$device/device/$key";

    return undef unless $file;

    # We need to support dump params to permit full testing when root params is set
    if ($dump) {
        foreach my $sub (split('/',dirname($file))) {
            next unless $sub;
            $dump->{$sub} = {} unless $dump->{$sub};
            $dump = $dump->{$sub};
        }
        $dump->{basename($file)} = getAllLines(file => $file);
    }

    my $value = getFirstLine(file => $root.$file, logger => $logger);

    return undef unless defined $value;
    $value = $1 if $value =~ /([[:print:]]*[[:alnum:]]+)/;

    return trimWhitespace($value);
}

sub _filterMultipath {
    my (%params) = (
        command => 'multipath -l',
        @_
    );

    my %hnames = map {$_ => 1} @{$params{names}};

    # parse multipath
    my (@groups, @group);
    foreach my $line (getAllLines(%params)) {
        if ($line =~ /^\w+ \(\w+\) dm-\d+ \w+/) {
            push @groups, [@group] if scalar @group;
            @group = ();
        } elsif ($line =~ / (sd[a-z]+) /) {
            push @group, $1;
        }
    }
    push @groups, [@group] if scalar @group;

    # filter
    foreach my $group (@groups) {
        # delete all but first element from each group
        for (my $i = 1; $i < scalar @$group; $i++) {
            delete $hnames{ @$group[$i] } ;
        }
    }

    return keys %hnames;
}

sub _readLinkFromSysFs {
    my ($path, $root, $dump) = @_;

    ## no critic (ExplicitReturnUndef)

    my @path = split('/', $path);

    return undef unless (!shift(@path) && shift(@path) eq 'sys');

    my @sys = ();

    # We need to support dump params to permit full testing when root params is set
    if ($dump) {
        foreach my $sub (split('/',dirname($path))) {
            next unless $sub;
            $dump->{$sub} = {} unless $dump->{$sub};
            $dump = $dump->{$sub};
        }
        $dump->{basename($path)} = [ link => ReadLink($path) ];
    }

    while (@path) {
        push @sys, shift(@path);
        my $link = ReadLink($root.'/sys/'.join('/', @sys));
        next unless $link;
        pop @sys;
        foreach my $sub (split('/',$link)) {
            if ($sub eq '..') {
                pop @sys;
            } else {
                push @sys, $sub;
            }
        }
    }

    return '/sys/'.join('/', @sys);
}

sub getInfoFromSmartctl {
    my (%params) = @_;

    # We need to support dump params to permit full testing when root params is set
    $params{file} = "$params{root}/smartctl-".basename($params{device})
        if $params{root};

    my @lines = getAllLines(
        %params,
        command => $params{device} ?
            "smartctl -i $params{device} " . ($params{extra} // "") : undef,
    );

    # We need to support dump params to permit full testing when root params is set
    $params{dump}->{"smartctl-".basename($params{device})} = @lines ? join("\n", @lines)."\n" : ""
        if $params{dump};

    return unless @lines;

    my $info = {
        TYPE        => 'disk',
        DESCRIPTION => 'SATA',
    };

    my $attrs = {
        DESCRIPTION => {
            src => ['transport protocol']
        },
        DISKSIZE => {
            src  => ['user capacity'],
            func => \&getCanonicalSize,
        },
        FIRMWARE => {
            src => ['revision', 'firmware version']
        },
        INTERFACE => {
            src => ['transport protocol', 'sata version is']
        },
        MANUFACTURER => {
            src  => ['vendor', 'model family', 'add. product id', 'device model', 'product'],
            func => \&getCanonicalManufacturer,
        },
        MODEL => {
            src => ['product', 'device model', 'model family']
        },
        SERIALNUMBER => {
            src => ['serial number']
        },
        TYPE => {
            src => ['device type']
        },
        WWN => {
            src  => ['lu wwn device id'],
            # remove whitespaces
            func => sub { my $str = shift; $str =~ s/\s+//g; $str; },
        }
    };

    my $regexp = {
        __default          => qr/^(\w+)/,
        __smartctl         => qr/^([^:]+?)\s*:\s*(.+)\s*$/,
        'user capacity'    => qr/([\d\.\,\s]+(?:\w+)?)/,
        'device model'     => qr/([\w\s\-]+)/,
        'firmware version' => qr/(\S+)/,
        'lu wwn device id' => qr/((?:0x)?[[:xdigit:]\h]+)/,
    };

    my %smartctl;

    for my $line (@lines) {
        next unless $line =~ $regexp->{__smartctl};
        $smartctl{lc $1} = $2;
    }

    while (my ($attr, $val) = each %$attrs) {
        for my $s (@{$val->{src}}) {
            next unless defined $smartctl{$s};

            my ($data) = ($smartctl{$s} =~ ($regexp->{$s} // $regexp->{__default}));

            $info->{$attr} = exists $val->{func} ? &{$val->{func}}($data) : $data;

            last;
        }
    }

    return $info;
}

sub getInterfacesFromIfconfig {
    my (%params) = (
        command => '/sbin/ifconfig -a',
        @_
    );
    my $handle = getFileHandle(%params);
    return unless $handle;

    my @interfaces;
    my $interface;

    my %types = (
        Ethernet => 'ethernet',
    );

    while (my $line = <$handle>) {
        if ($line =~ /^$/) {
            # end of interface section
            push @interfaces, $interface if $interface;
            next;
        }

        if ($line =~ /^([\w\d.]+)/) {
            # new interface

            $interface = {
                STATUS      => 'Down',
                DESCRIPTION => $1
            }

        }
        if ($line =~ /
            inet \s ($ip_address_pattern) \s+
            netmask \s ($ip_address_pattern) \s+
            broadcast \s $ip_address_pattern
        /x) {
            $interface->{IPADDRESS} = $1;
            $interface->{IPMASK} = $2;
        }

        if ($line =~ /
            ether \s ($mac_address_pattern)
            .+
            \( Ethernet \)
        /x) {
            $interface->{MACADDR} = $1;
            $interface->{TYPE} = 'ethernet';
        }

        if ($line =~ /inet6 \s (\S+)/x) {
            $interface->{IPADDRESS6} = $1;
        }

        if ($line =~ /inet addr:($ip_address_pattern)/i) {
            $interface->{IPADDRESS} = $1;
        }

        if ($line =~ /Mask:($ip_address_pattern)/) {
            $interface->{IPMASK} = $1;
        }

        if ($line =~ /inet6 addr: (\S+)/i) {
            $interface->{IPADDRESS6} = $1;
        }

        if ($line =~ /hwadd?r\s+($mac_address_pattern)/i) {
            $interface->{MACADDR} = $1;
        }

        if ($line =~ /^\s+UP\s/) {
            $interface->{STATUS} = 'Up';
        }

        if ($line =~ /flags=.*[<,]UP[>,]/) {
            $interface->{STATUS} = 'Up';
        }

        if ($line =~ /Link encap:(\S+)/) {
            $interface->{TYPE} = $types{$1};
        }

    }
    close $handle;

    return @interfaces;
}

sub getInterfacesInfosFromIoctl {
    my (%params) = (
        interface => 'eth0',
        @_
    );

    return unless $params{interface};

    # We don't support this feature on remote inventory
    return if $GLPI::Agent::Tools::remote;

    my $logger = $params{logger};

    socket(my $socket, PF_INET, SOCK_DGRAM, 0)
        or return ;

    # Pack command in ethtool_cmd struct
    my $cmd = pack("L3SC6L2SC2L3", ETHTOOL_GSET);

    # Pack request for ioctl
    my $request = pack("a16p", $params{interface}, $cmd);

    my $retval = ioctl($socket, SIOCETHTOOL, $request) || -1;
    return if ($retval < 0);

    # Unpack returned datas
    my @datas = unpack("L3SC6L2SC2L3", $cmd);

    # Actually only speed value is requested and extracted
    my $datas = {
        SPEED => $datas[3]|$datas[12]<<16
    };

    # Forget speed value if got unknown speed special value
    if ($datas->{SPEED} == SPEED_UNKNOWN) {
        delete $datas->{SPEED};
        $logger->debug2("Unknown speed found on $params{interface}")
            if $logger;
    }

    return $datas;
}

sub getInterfacesFromIp {
    my (%params) = (
        command => '/sbin/ip addr show',
        @_
    );

    my $handle = getFileHandle(%params);
    return unless $handle;

    my (@interfaces, @addresses, $interface);

    while (my $line = <$handle>) {
        if ($line =~ /^\d+:\s+(\S+): <([^>]+)>/) {

            if (@addresses) {
                push @interfaces, @addresses;
                undef @addresses;
            } elsif ($interface) {
                push @interfaces, $interface;
            }

            my ($name, $flags) = ($1, $2);
            my $status =
                (any { $_ eq 'UP' } split(/,/, $flags)) ? 'Up' : 'Down';

            $interface = {
                DESCRIPTION => $name,
                STATUS      => $status
            };
        } elsif ($line =~ /link\/\S+ ($any_mac_address_pattern)?/) {
            $interface->{MACADDR} = $1;
        } elsif ($line =~ /inet6 (\S+)\/(\d{1,2})/) {
            my $address = $1;
            my $mask    = getNetworkMaskIPv6($2);
            my $subnet  = getSubnetAddressIPv6($address, $mask);

            push @addresses, {
                IPADDRESS6  => $address,
                IPMASK6     => $mask,
                IPSUBNET6   => $subnet,
                STATUS      => $interface->{STATUS},
                DESCRIPTION => $interface->{DESCRIPTION},
                MACADDR     => $interface->{MACADDR}
            };
        } elsif ($line =~ /
            inet \s
            ($ip_address_pattern)(?:\/(\d{1,3}))? \s
            .* \s
            (\S+)$
            /x) {
            my $address = $1;
            my $mask    = getNetworkMask($2);
            my $subnet  = getSubnetAddress($address, $mask);
            my $name    = $3;

            # the name associated with the address differs from the current
            # interface if the address is actually attached to an alias
            push @addresses, {
                IPADDRESS   => $address,
                IPMASK      => $mask,
                IPSUBNET    => $subnet,
                STATUS      => $interface->{STATUS},
                DESCRIPTION => $name,
                MACADDR     => $interface->{MACADDR}
            };
        }
    }
    close $handle;

    if (@addresses) {
        push @interfaces, @addresses;
        undef @addresses;
    } elsif ($interface) {
        push @interfaces, $interface;
    }

    return @interfaces;
}

1;
__END__

=head1 NAME

GLPI::Agent::Tools::Linux - Linux generic functions

=head1 DESCRIPTION

This module provides some generic functions for Linux.

=head1 FUNCTIONS

=head2 getDevicesFromUdev(%params)

Returns a list of devices, by parsing /dev/.udev directory.
This directory is not exported anymore with recent udev.

Availables parameters:

=over

=item logger a logger object

=back

=head2 getDevicesFromHal(%params)

Returns a list of devices, by parsing lshal output.

Availables parameters:

=over

=item logger a logger object

=item command the exact command to use (default: /usr/sbin/lshal)

=item file the file to use, as an alternative to the command

=back

=head2 getDevicesFromProc(%params)

Returns a list of devices, by parsing /proc filesystem.

Availables parameters:

=over

=item logger a logger object

=back

=head2 getCPUsFromProc(%params)

Returns a list of cpus, by parsing /proc/cpuinfo file

Availables parameters:

=over

=item logger a logger object

=item file the file to use (default: /proc/cpuinfo)

=back

=head2 getInfoFromSmartctl(%params)

Returns some information about a device, using smartctl.

Availables parameters:

=over

=item logger a logger object

=item device the device to use

=item file the file to use

=back

=head2 getInterfacesFromIfconfig(%params)

Returns the list of interfaces, by parsing ifconfig command output.

Availables parameters:

=over

=item logger a logger object

=item command the command to use (default: /sbin/ifconfig -a)

=item file the file to use

=back

=head2 getInterfacesInfosFromIoctl(%params)

Returns interface datas, by parsing results from ethtool system call request.

Availables parameters:

=over

=item logger a logger object

=item interface the interface name to use (default: eth0)

=back

=head2 getInterfacesFromIp(%params)

Returns the list of interfaces, by parsing ip command output.

Availables parameters:

=over

=item logger a logger object

=item command the command to use (default: /sbin/ip addr show)

=item file the file to use

=back
