#!/usr/local/cpanel/3rdparty/bin/perl

# cpanel - scripts/dovecot_maintenance             Copyright 2022 cPanel, L.L.C.
#                                                           All rights reserved.
# copyright@cpanel.net                                         http://cpanel.net
# This code is subject to the cPanel license. Unauthorized copying is prohibited

package scripts::dovecot_maintenance;

=pod

=head1 NAME

dovecot_maintenance - Run nightly maintenance for dovecot which includes
                      purging deleted messages from mdbox.

=head1 SYNOPSIS

/usr/local/cpanel/scripts/dovecot_maintenance [options]

    Options:
      --help       This help message
      --background Run in the background

=head1 DESCRIPTION

All deleted email will be purged from mdbox users
who have logged in since this script was last run.

This program will also purge all expired APNs
registrations

=cut

use strict;
use Cpanel::IONice             ();
use Cpanel::PwCache            ();
use Cpanel::PwCache::Build     ();
use Cpanel::Config::LoadCpConf ();
use Cpanel::Config::LoadConfig ();
use Cpanel::ConfigFiles        ();
use Cpanel::Dovecot            ();
use Cpanel::Dovecot::Utils     ();
use Cpanel::AdvConfig          ();
use Cpanel::Locale             ();

use Cpanel::AcctUtils::DomainOwner::Tiny ();
use Cpanel::AcctUtils::Lookup            ();
use Cpanel::FileUtils::Open              ();
use Cpanel::Email::Exists                ();

use Cpanel::FileUtils::Dir ();

use Cpanel::SQLite::Compat ();

use DBD::SQLite         ();
use Cpanel::DBI::SQLite ();

use Cpanel::APNS::Mail::DB ();

use File::Path   ();
use Getopt::Long ();
use Pod::Usage   ();
use Umask::Local ();
use Try::Tiny;

our $DAYS_TO_KEEP_APNS_REGISTRATIONS = 7;

my $background = 0;
my $help       = 0;

unless ( caller() ) {
    Getopt::Long::GetOptions( 'background' => \$background, 'help' => \$help );
    Pod::Usage::pod2usage( -verbose => 2 ) if $help;

    if ($background) {
        require Cpanel::Daemonizer::Tiny;
        my $pid = Cpanel::Daemonizer::Tiny::run_as_daemon(
            sub {
                ####
                # The next two calls are unchecked because it cannot be captured when running as a daemon
                Cpanel::FileUtils::Open::sysopen_with_real_perms( \*STDERR, $Cpanel::ConfigFiles::CPANEL_ROOT . '/logs/error_log', 'O_WRONLY|O_APPEND|O_CREAT', 0600 );
                open( STDOUT, '>&', \*STDERR ) || warn "Failed to redirect STDOUT to STDERR";

                exit( __PACKAGE__->script() );
            }
        );
    }
    else {
        exit( __PACKAGE__->script() );
    }
}

our $DEFAULT_IO_NICE = 7;

sub script {
    my ($class) = @_;

    my $self = bless {}, $class;

    $self->_init();

    local $| = 1;
    my $exit_status = 0;

    # Order matters since for mdbox expunge will only mark it for purge
    foreach my $op (qw(_purge_deleted_messages _purge_expired_xaps_registrations)) {
        try {
            $self->$op();
        }
        catch {
            warn $_;
            $exit_status = 1;
        };
    }

    return $exit_status;
}

sub _init {
    my ($self) = @_;

    $self->{'mailbox_formats'} = scalar Cpanel::Config::LoadConfig::loadConfig( "/etc/mailbox_formats", undef, ": " );
    $self->{'dovecot_conf'}    = Cpanel::AdvConfig::load_app_conf('dovecot');

    Cpanel::AcctUtils::DomainOwner::Tiny::build_domain_cache();
    Cpanel::PwCache::Build::init_passwdless_pwcache();

    return;
}

sub _ionice {
    my ($self) = @_;
    return if $self->{'did_ionice'};
    $self->{'did_ionice'} = 1;
    my $cpconf_ref = Cpanel::Config::LoadCpConf::loadcpconf();
    if ( Cpanel::IONice::ionice( 'best-effort', exists $cpconf_ref->{'ionice_dovecot_maintenance'} ? $cpconf_ref->{'ionice_dovecot_maintenance'} : $$DEFAULT_IO_NICE ) ) {
        print "[dovecot_maintenance] Setting I/O priority to reduce system load: " . Cpanel::IONice::get_ionice() . "\n";
    }
    return 1;
}

sub _purge_deleted_messages {
    my ($self) = @_;

    return if !-d $Cpanel::Dovecot::LASTLOGIN_DIR;    # may not be created yet

    my $nodes_ar = Cpanel::FileUtils::Dir::get_directory_nodes($Cpanel::Dovecot::LASTLOGIN_DIR);
    my $locale   = $self->_locale();
    foreach my $username (@$nodes_ar) {
        if ( index( $username, q{__cpanel__service__auth__} ) == -1 && $self->_has_mdbox($username) ) {
            $self->_ionice();
            print $locale->maketext( "Purging deleted messages for “[_1]” …", $username );
            Cpanel::Dovecot::Utils::purge($username);
            print $locale->maketext("Done") . "\n";
        }

        if ( -d "$Cpanel::Dovecot::LASTLOGIN_DIR/$username" ) {

            # Handle user/sent logins
            try {
                File::Path::rmtree("$Cpanel::Dovecot::LASTLOGIN_DIR/$username");
            }
            catch {
                local $@ = $_;
                warn;
            };
        }
        else {
            # Handle normal logins
            unlink("$Cpanel::Dovecot::LASTLOGIN_DIR/$username");
        }
    }

    return 1;

}

sub _locale {
    my ($self) = @_;
    return ( $self->{'locale'} ||= Cpanel::Locale->get_handle() );
}

sub _has_mdbox {
    my ( $self, $username ) = @_;

    my $system_user;

    # get_system_user generates an exception when the user or the
    # domain does not exist. UserNotFound/DomainDoesNotExist.
    #
    # anything else is a fail
    try {
        $system_user = Cpanel::AcctUtils::Lookup::get_system_user($username);
    }
    catch {
        local $@ = $_;
        die if !try { $_->isa('Cpanel::Exception::UserNotFound') || $_->isa('Cpanel::Exception::DomainDoesNotExist') };
    };

    return 0 if !$system_user;

    # The email account may have a different setting than the main account, so
    # we check here.
    if ( $username =~ tr{@}{} ) {
        my ( $user, $domain ) = split /@/, $username;
        my $homedir = Cpanel::PwCache::gethomedir($system_user);

        # cannot have mdbox if there is no dir
        if ( !-d "$homedir/mail/$domain/$user/storage" ) {
            if ( !$! ) {
                warn "“$homedir/mail/$domain/$user/storage” exists but isn’t a directory??";
            }
            elsif ( !$!{'ENOENT'} ) {
                warn "stat($homedir/mail/$domain/$user/storage) as EUID $>: $!";
            }

            return 0;
        }

        my $size = ( stat("$homedir/mail/$domain/$user/mailbox_format.cpanel") )[7];
        if ( !$size ) {
            require Cpanel::AcctUtils::Lookup::MailUser;

            # no mailbox_format.cpanel file? fallback to the logic
            # we use to lookup a user
            my $response;
            try {
                $response = Cpanel::AcctUtils::Lookup::MailUser::lookup_mail_user( $username, q{} );
            }
            catch {
                local $@ = $_;
                warn;
            };
            if ( $response && $response->{'user_info'}{'mailbox'}{'format'} eq 'mdbox' ) {
                return 1;
            }
            return 0;
        }
        return $size == length 'mdbox' ? 1 : 0;
    }

    return $self->{'mailbox_formats'}->{$system_user} eq 'mdbox' ? 1 : 0;
}

sub _find_valid_users_from_query {
    my ( $self, $query ) = @_;

    my ( @valid, %invalid );

  EXPIRED_ENTRY:
    while ( my $entry = $query->fetchrow_hashref() ) {
        local $@;
        if (
            !try {
                my $system_user = Cpanel::AcctUtils::Lookup::get_system_user( $entry->{'username'} );
                local $Cpanel::homedir = Cpanel::PwCache::gethomedir($system_user);
                Cpanel::Email::Exists::pop_exists( split( q{@}, $entry->{'username'} ) );
            }
        ) {
            print "$entry->{'username'} does not exist. Removing stale entries.\n";
            $invalid{ $entry->{'username'} } = 1;
            next EXPIRED_ENTRY;
        }

        push @valid, $entry;
    }
    return ( \@valid, \%invalid );
}

sub _purge_expired_xaps_registrations {
    my ($self) = @_;

    return Cpanel::APNS::Mail::DB->new()->purge_registrations_older_than($DAYS_TO_KEEP_APNS_REGISTRATIONS);
}

1;