package PVE::LDAP;

use strict;
use warnings;

use Net::IP;
use Net::LDAP;
use Net::LDAP::Control::Paged;
use Net::LDAP::Constant qw(LDAP_CONTROL_PAGED);

sub ldap_connect {
    my ($servers, $scheme, $port, $opts) = @_;

    my $start_tls = 0;

    if ($scheme eq 'ldap+starttls') {
        $scheme = 'ldap';
        $start_tls = 1;
    }

    my %ldap_opts = (
        scheme => $scheme,
        port => $port,
        timeout => 10,
    );

    my $hosts = [];
    for my $host (@$servers) {
        if (Net::IP::ip_is_ipv6($host)) {
            push @$hosts, "[$host]";
        } else {
            push @$hosts, $host;
        }
    }

    for my $opt (qw(clientcert clientkey capath cafile sslversion verify)) {
        $ldap_opts{$opt} = $opts->{$opt} if $opts->{$opt};
    }

    my $ldap = Net::LDAP->new($hosts, %ldap_opts) || die "$@\n";

    if ($start_tls) {
        my $res = $ldap->start_tls(%$opts);
        die $res->error . "\n" if $res->code;
    }

    return $ldap;
}

sub ldap_bind {
    my ($ldap, $dn, $pw) = @_;

    my $res;
    if (defined($dn) && defined($pw)) {
        $res = $ldap->bind($dn, password => $pw);
    } else { # anonymous bind
        $res = $ldap->bind();
    }

    my $code = $res->code;
    my $err = $res->error;

    die "ldap bind failed: $err\n" if $code;
}

sub get_user_dn {
    my ($ldap, $name, $attr, $base_dn) = @_;

    # search for dn
    my $result = $ldap->search(
        base => $base_dn // "",
        scope => "sub",
        filter => "$attr=$name",
        attrs => ['dn'],
    );
    die $result->error . "\n" if $result->code;
    return undef if !$result->entries;
    my @entries = $result->entries;
    return $entries[0]->dn;
}

sub auth_user_dn {
    my ($ldap, $dn, $pw, $noerr) = @_;

    if (!$dn) {
        return undef if $noerr;
        die "user dn is empty\n";
    }

    my $res = $ldap->bind($dn, password => $pw);

    my $code = $res->code;
    my $err = $res->error;

    if ($code) {
        return undef if $noerr;
        die "$err\n";
    }

    return 1;
}

sub query_users {
    my ($ldap, $filter, $attributes, $base_dn, $classes) = @_;

    # build filter from given filter and attribute list
    my $tmp = "(|";
    foreach my $att (@$attributes) {
        $tmp .= "($att=*)";
    }
    $tmp .= ")";

    if ($classes) {
        $tmp = "(&$tmp(|";
        for my $class (@$classes) {
            $tmp .= "(objectclass=$class)";
        }
        $tmp .= "))";
    }

    if ($filter) {
        $filter = "($filter)" if $filter !~ m/^\(.*\)$/;
        $filter = "(&${filter}${tmp})";
    } else {
        $filter = $tmp;
    }

    my $page = Net::LDAP::Control::Paged->new(size => 900);

    my @args = (
        base => $base_dn // "",
        scope => "subtree",
        filter => $filter,
        control => [$page],
        attrs => [@$attributes, 'memberOf'],
    );

    my $cookie;
    my $err;
    my $users = [];

    while (1) {

        my $mesg = $ldap->search(@args);

        # stop on error
        if ($mesg->code) {
            $err = "ldap user search error: " . $mesg->error;
            last;
        }

        #foreach my $entry ($mesg->entries) { $entry->dump; }
        foreach my $entry ($mesg->entries) {
            my $user = {
                dn => $entry->dn,
                attributes => {},
                groups => [$entry->get_value('memberOf')],
            };

            foreach my $attr (@$attributes) {
                my $vals = [$entry->get_value($attr)];
                if (scalar(@$vals)) {
                    $user->{attributes}->{$attr} = $vals;
                }
            }

            push @$users, $user;
        }

        # Get cookie from paged control
        my ($resp) = $mesg->control(LDAP_CONTROL_PAGED) or last;
        $cookie = $resp->cookie;

        last if (!defined($cookie) || !length($cookie));

        # Set cookie in paged control
        $page->cookie($cookie);
    }

    if (defined($cookie) && length($cookie)) {
        # We had an abnormal exit, so let the server know we do not want any more
        $page->cookie($cookie);
        $page->size(0);
        $ldap->search(@args);
        $err = "LDAP user query unsuccessful" if !$err;
    }

    die "$err\n" if $err;

    return $users;
}

sub query_groups {
    my ($ldap, $base_dn, $classes, $filter, $group_name_attr) = @_;

    my $tmp = "(|";
    for my $class (@$classes) {
        $tmp .= "(objectclass=$class)";
    }
    $tmp .= ")";

    if ($filter) {
        $filter = "($filter)" if $filter !~ m/^\(.*\)$/;
        $filter = "(&${filter}${tmp})";
    } else {
        $filter = $tmp;
    }

    my $page = Net::LDAP::Control::Paged->new(size => 100);

    my $attrs = ['member', 'uniqueMember'];
    push @$attrs, $group_name_attr if $group_name_attr;
    my @args = (
        base => $base_dn,
        scope => "subtree",
        filter => $filter,
        control => [$page],
        attrs => $attrs,
    );

    my $cookie;
    my $err;
    my $groups = [];

    while (1) {

        my $mesg = $ldap->search(@args);

        # stop on error
        if ($mesg->code) {
            $err = "ldap group search error: " . $mesg->error;
            last;
        }

        foreach my $entry ($mesg->entries) {
            my $group = {
                dn => $entry->dn,
                members => [],
            };
            my $members = [$entry->get_value('member')];
            if (!scalar(@$members)) {
                $members = [$entry->get_value('uniqueMember')];
            }
            $group->{members} = $members;
            if ($group_name_attr && (my $name = $entry->get_value($group_name_attr))) {
                $group->{name} = $name;
            }
            push @$groups, $group;
        }

        # Get cookie from paged control
        my ($resp) = $mesg->control(LDAP_CONTROL_PAGED) or last;
        $cookie = $resp->cookie;

        last if (!defined($cookie) || !length($cookie));

        # Set cookie in paged control
        $page->cookie($cookie);
    }

    if ($cookie) {
        # We had an abnormal exit, so let the server know we do not want any more
        $page->cookie($cookie);
        $page->size(0);
        $ldap->search(@args);
        $err = "LDAP group query unsuccessful" if !$err;
    }

    die "$err\n" if $err;

    return $groups;
}

1;