package Sysinfo;

use strict;
use POSIX;
use Sys::Hostname;

use Exporter;
our @ISA = ('Exporter');     # Inherit from Exporter
our @EXPORT_OK = qw(cpuinfo meminfo osinfo processid diskinfo diskspaces);

use LogUtils;

our $log = LogUtils->getLogger(__PACKAGE__);


# Return PIDs of named commands owned by the current user
# Only one pid is returned per command name

sub processid (@) {

    my @procs = `ps -u $< -o pid,comm 2>/dev/null`;
    if ( $? != 0 ) {
        $log->info("Failed running: ps -u $< -o pid,comm");
        $log->warning("Failed listing processes");
        return {};
    }
    shift @procs; # throw away header line

    # make hash of comm => pid
    my %all;
    /\s*(\d+)\s+(.+)/ and $all{$2} = $1 for @procs;

    my %pids;
    foreach my $name ( @_ ) {
        $pids{$name} = $all{$name} if $all{$name};
    }
    return \%pids;
}


sub cpuinfo {

    my $info = {};

    my $nsockets; # total number of physical cpu sockets
    my $ncores;   # total number of cpu cores
    my $nthreads; # total number of hardware execution threads

    if (-f "/proc/cpuinfo") {
        # Linux variant

        my %sockets; # cpu socket IDs
        my %cores;   # cpu core IDs

        open (CPUINFO, "</proc/cpuinfo")
            or $log->warning("Failed opening /proc/cpuinfo: $!");
        while ( my $line = <CPUINFO> ) {
            if ($line=~/^model name\s*:\s+(.*)$/) {
                $info->{cpumodel} = $1;
            } elsif ($line=~/^vendor_id\s+:\s+(.*)$/) {
                $info->{cpuvendor} = $1;
            } elsif ($line=~/^cpu MHz\s+:\s+(.*)$/) {
                $info->{cpufreq} = int $1;
            } elsif ($line=~/^stepping\s+:\s+(.*)$/) {
                $info->{cpustepping} = int $1;
            } elsif ($line=~/^processor\s*:\s+(\d+)$/) {
                ++$nthreads;
            } elsif ($line=~/^physical id\s*:\s+(\d+)$/) {
                ++$sockets{$1};
            } elsif ($line=~/^core id\s*:\s+(\d+)$/) {
                ++$cores{$1};
            }
        }
        close CPUINFO;

        if ($info->{cpumodel} =~ m/^(.*?)\s+@\s+([.\d]+)GHz$/) {
            $info->{cpumodel} = $1;
            $info->{cpufreq} = int($2*1000);
        } elsif ($info->{cpumodel} =~ m/\s+([.\d]+)GHz$/) { 
            $info->{cpufreq} = int($1*1000);
        } elsif ($info->{cpumodel} =~ m/\s+([.\d]+)MHz$/) { 
            $info->{cpufreq} = int($1);
        }

        # count total cpu cores and sockets
        $ncores = scalar keys %cores;
        $nsockets = scalar keys %sockets;

        if ($nthreads) {
            # if /proc/cpuinfo does not provide socket and core IDs,
            # assume every thread represents a separate cpu
            $ncores = $nthreads unless $ncores;
            $nsockets = $nthreads unless $nsockets;
        }

    } elsif (-x "/usr/sbin/system_profiler") {
        # OS X

        my @lines = `/usr/sbin/system_profiler SPHardwareDataType`;
        $log->warning("Failed running system_profiler: $!") if $?;
        for my $line ( @lines ) {
            if ($line =~ /Processor Name:\s*(.*)/) {
                $info->{cpumodel} = $1;
            } elsif ($line =~ /Processor Speed:\s*([.\d]+) (\w+)/) {
                if ($2 eq "MHz") {
                    $info->{cpufreq} = int $1;
                } elsif ($2 eq "GHz") {
                    $info->{cpufreq} = int 1000*$1;
                }
            } elsif ($line =~ /Number Of Processors:\s*(.+)/) {
                $nsockets = $1;
            } elsif ($line =~ /Total Number Of Cores:\s*(.+)/) {
                $ncores = $1;
                $nthreads = $1; # Assume 1 execution thread per core (Ouch!)
            }
        }

    } elsif (-x "/usr/bin/kstat" ) {
        # Solaris

        my %chips;
        eval {
            require Sun::Solaris::Kstat;
            my $ks = Sun::Solaris::Kstat->new();
            my $cpuinfo = $ks->{cpu_info};
            $log->error("kstat: key not found: cpu_info") unless defined $cpuinfo;
            for my $id (keys %$cpuinfo) {
               my $info = $cpuinfo->{$id}{"cpu_info$id"};
               $log->error("kstat: key not found: cpu_info$id") unless defined $info;
               $chips{$info->{chip_id}}++;
               $nthreads++;
            }
            my $info = $cpuinfo->{0}{"cpu_info0"};
            $log->error("kstat: key not found: cpu_info0") unless defined $info;
            # $info->{cpumodel} = $info->{cpu_type}; # like sparcv9
            $info->{cpumodel} = $info->{implementation}; # like UltraSPARC-III+
            $info->{cpufreq} = int $info->{clock_MHz};
        };
        if ($@) {
            $log->error("Failed running module Sun::Solaris::Kstat: $@");
        }
        $nsockets = $ncores = scalar keys %chips;

    } else {
        $log->warning("Unsupported operating system");
    }

    $info->{cputhreadcount} = $nthreads if $nthreads;
    $info->{cpucorecount} = $ncores if $ncores;
    $info->{cpusocketcount} = $nsockets if $nsockets;

    return $info;

}

sub meminfo {
    my ($memtotal, $swaptotal);
    if (-f "/proc/cpuinfo") {
        # Linux variant
        open (MEMINFO, "</proc/meminfo")
            or $log->warning("Failed opening /proc/meminfo: $!");
        while ( my $line = <MEMINFO> ) {
            if ($line =~ /^MemTotal:\s+(.*) kB$/) {
                $memtotal = int ($1/1024);
            } elsif ($line =~ /^SwapTotal:\s+(.*) kB$/) {
                $swaptotal = int ($1/1024);
            }
        }
    }
    my $info = {};
    $info->{pmem} = $memtotal if $memtotal;
    $info->{vmem} = $memtotal + $swaptotal if $memtotal and $swaptotal;
    return $info;
}


sub osinfo {
    my $info = {};
    my ($sysname, $nodename, $release, $version, $machine) = POSIX::uname();
    $info->{machine} = $machine;
    $info->{sysname} = $sysname;
    $info->{release} = $release;

    if ($sysname =~ /linux/i) {
        my ($msg, $id, $descr, $version);
        if (-x '/usr/bin/lsb_release' or -x '/bin/lsb_release') {
            if (open RELEASE, "lsb_release -a 2>&1 |") {
                while (<RELEASE>) {
					$msg = $1 if m/^(No.*)/;
                    $id = lc $1 if m/^Distributor ID:\s+(.*)/;
                    $descr = $1 if m/^Description:\s+(.*)/;
                    $version = $1 if m/^Release:\s+([.\d]+)/;
                }
            }
            close RELEASE;
        } elsif (open RELEASE, '< /etc/lsb-release') {
            while (<RELEASE>) {
                $id = lc $1 if m/^DISTRIB_ID=(.*)/;
                $descr = $1 if m/^DISTRIB_DESCRIPTION=(.*)/;
                $version = $1 if m/^DISTRIB_RELEASE=([.\d]+)/;
            }
            close RELEASE;
        } elsif (open RELEASE, '< /etc/redhat-release') {
            ($descr, $version) = ($1,$2) if <RELEASE> =~ m/(.*) release ([.\d]+)/;
            close RELEASE;
        } elsif (open RELEASE, '< /etc/debian_version') {
            $version = $1 if <RELEASE> =~ m/^([.\d]+)$/;
            $id = 'debian';
            close RELEASE;
        } elsif (open RELEASE, '< /etc/SuSE-release') {
            while (<RELEASE>) {
                $version = $1 if m/^VERSION\s*=\s*([.\d]+)/;
            }
            $id = 'suse';
            close RELEASE;
        } elsif (open RELEASE, '< /etc/gentoo-release') {
            $version = $1 if <RELEASE> =~ m/.* version ([.\d]+)/;
            $id = 'gentoo';
            close RELEASE;
        }
        # Try to stay within the predefined values for OSName_t from GLUE2 spec (GFD.147).
        if ($descr) {
            $id = 'centos' if $descr =~ m/^CentOS/i;
            $id = 'fedoracore' if $descr =~ m/^Fedora/i;
            $id = 'scientificlinux' if $descr =~ m/^Scientific Linux/i;
            $id = 'scientificlinuxcern' if $descr =~ m/^Scientific Linux CERN/i;
            $id = 'redhatenterpriseas' if $descr =~ m/^Red Hat Enterprise/i and not $id;
        }
        $info->{osname} = $id if $id;
        $info->{osversion} = $version if $version;

    } elsif ($sysname eq 'Darwin') {
        my $version = `sw_vers -productVersion`;
        chomp $version;
        if ($version =~ m/10\.[\d.]+/) {
            my $name;
            $info->{osname} = 'panther' if $version =~ m/^10\.3/;
            $info->{osname} = 'tiger' if $version =~ m/^10\.4/;
            $info->{osname} = 'leopard' if $version =~ m/^10\.5/;
            $info->{osname} = 'snowleopard' if $version =~ m/^10\.6/;
            $info->{osversion} = $version;
        }

    } elsif ($sysname eq 'SunOS') {
        $release =~ s/^5\.//; # SunOS 5.10 == solaris 10
        $info->{osname} = 'solaris';
        $info->{osversion} = $release;
    }
    return $info;
}

#
# Returns disk space (total and free) in MB on a filesystem
#
sub diskinfo ($) {
    my $path = shift;
    my ($diskfree, $disktotal, $mountpoint);

    if ( -d "$path") {
        # check if on afs
        if ($path =~ m#/afs/#) {
            my @dfstring =`fs listquota $path 2>/dev/null`;
            if ($? != 0) {
                $log->warning("Failed running: fs listquota $path");
            } elsif ($dfstring[-1] =~ /\s+(\d+)\s+(\d+)\s+\d+%\s+\d+%/) {
                $disktotal = int $1/1024;
                $diskfree  = int(($1 - $2)/1024);
                $mountpoint = '/afs';
            } else {
                $log->warning("Failed interpreting output of: fs listquota $path");
            }
        # "ordinary" disk
        } else {
            my @dfstring =`df -k $path 2>/dev/null`;
            if ($? != 0) {
                $log->warning("Failed running: df -k $path");

            # The first column may be printed on a separate line.
            # The relevant numbers are always on the last line.
            } elsif ($dfstring[-1] =~ /\s+(\d+)\s+\d+\s+(\d+)\s+\d+%\s+(\/\S*)$/) {
    	        $disktotal = int $1/1024;
    	        $diskfree  = int $2/1024;
                $mountpoint = $3;
            } else {
                $log->warning("Failed interpreting output of: df -k $path");
            }
        }
    } else {
        $log->warning("No such directory: $path");
    }

    return undef if not defined $disktotal;
    return {megstotal => $disktotal, megsfree => $diskfree, mountpoint => $mountpoint};
}


# Given a list of paths, it finds the set of mount points of the filesystems
# containing the paths. It then returns a hash with these keys:
#     ndisks: number of distinct nount points
#     freesum: sum of free space on all mount points
#     freemin: minimum free space of any mount point
#     freemax: maximum free space of any mount point
#     totalsum: sum of total space on all mountpoints
#     totalmin: minimum total space of any mount point
#     totalmax: maximum total space of any mount point
#     errors: the number of non-existing paths
sub diskspaces {
    my ($freesum, $freemin, $freemax);
    my ($totalsum, $totalmin, $totalmax);
    my $errors = 0;
    my %mounts;
    for my $path (@_) {
        my $di = diskinfo($path);
        if ($di) {
            my ($total, $free, $mount) = ($di->{megstotal},$di->{megsfree},$di->{mountpoint});
            $mounts{$mount}{free} = $free;
            $mounts{$mount}{total} = $total;
        } else {
            ++$errors;
        }
    }
    for my $stats (values %mounts) {
        if (defined $freesum) {
            $freesum += $stats->{free};
            $freemin = $stats->{free} if $freemin > $stats->{free};
            $freemax = $stats->{free} if $freemax < $stats->{free};
            $totalsum += $stats->{total};
            $totalmin = $stats->{total} if $totalmin > $stats->{total};
            $totalmax = $stats->{total} if $totalmax < $stats->{total};
        } else {
            $freesum = $freemin = $freemax = $stats->{free};
            $totalsum = $totalmin = $totalmax = $stats->{total};
        }
    }
    return ( ndisks => scalar keys %mounts,
             freesum => $freesum || 0,
             freemin => $freemin || 0,
             freemax => $freemax || 0,
             totalsum => $totalsum || 0,
             totalmin => $totalmin || 0,
             totalmax => $totalmax || 0,
             errors => $errors );
}


1;