# --
# Copyright (C) 2001-2021 OTRS AG, https://otrs.com/
# Copyright (C) 2021 Znuny GmbH, https://znuny.org/
# --
# This software comes with ABSOLUTELY NO WARRANTY. For details, see
# the enclosed file COPYING for license information (GPL). If you
# did not receive this file, see https://www.gnu.org/licenses/gpl-3.0.txt.
# --

package Kernel::System::Stats;

use strict;
use warnings;

use MIME::Base64;

use POSIX qw(ceil);

use Kernel::Language              qw(Translatable);
use Kernel::System::VariableCheck qw(:all);
use Kernel::Output::HTML::Statistics::View;

our @ObjectDependencies = (
    'Kernel::Config',
    'Kernel::Language',
    'Kernel::Output::HTML::Statistics::View',
    'Kernel::System::Cache',
    'Kernel::System::DateTime',
    'Kernel::System::Group',
    'Kernel::System::Log',
    'Kernel::System::Main',
    'Kernel::System::Storable',
    'Kernel::System::User',
    'Kernel::System::XML',
);

=head1 NAME

Kernel::System::Stats - stats lib

=head1 DESCRIPTION

All stats functions.

=head2 Explanation for the time zone parameter

The time zone parameter is available, if the statistic is a dynamic statistic. The selected periods in the frontend are time zone neutral and for the
search parameters, the selection will be converted to the OTRS time zone, because the times
are stored within this time zone in the database.

This means e.g. if an absolute period of time from 2015-08-01 00:00:00 to 2015-09-10 23:59:59 and a time zone with an offset of +6 hours has been selected,
the period will be converted from the +6 time zone to the OTRS time zone for the search parameter,
so that the right time will be used for searching the database. Given that the OTRS time zone is set to UTC, this
would result in a period of 2015-07-31 18:00:00 to 2015-09-10 17:59:59 UTC.

For a relative time period, e. g. the last 10 full days, and a time zone with an offset of +10 hours, a DateTime object with the +10 time zone will be created
for the current time. For the period end date, this date will be taken and extended to the end of the day. Then, 10 full days will be subtracted from this.
This is the start of the period, which will be extended to 00:00:00. Start and end date will be converted to the time zone of OTRS to search the database.

Example for relative time period 'last 10 full days' with selected time zone offset +10 hours, current date/time within this time zone 2015-09-10 16:00:00, OTRS time zone is UTC:
End date: 2015-09-10 16:00:00 -> extended to 2015-09-10 23:59:59 -> 2015-09-10 13:59:59 OTRS time zone (UTC)
Start date: 2015-09-10 16:00:00 - 10 days -> 2015-08-31 16:00:00 -> extended to 00:00:00: 2015-09-01 00:00:00 -> 2015-08-31 14:00:00 OTRS time zone (UTC)

=head1 PUBLIC INTERFACE

=head2 new()

Don't use the constructor directly, use the ObjectManager instead:

    my $StatsObject = $Kernel::OM->Get('Kernel::System::Stats');

=cut

sub new {
    my ( $Type, %Param ) = @_;

    # allocate new hash for object
    my $Self = {};
    bless( $Self, $Type );

    # temporary directory
    $Self->{StatsTempDir} = $Kernel::OM->Get('Kernel::Config')->Get('Home') . '/var/stats/';

    return $Self;
}

=head2 StatsAdd()

add new empty stats

    my $StatID = $StatsObject->StatsAdd(
        UserID => $UserID,
    );

=cut

sub StatsAdd {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "Need $Needed.",
            );
            return;
        }
    }

    # get needed objects
    my $XMLObject      = $Kernel::OM->Get('Kernel::System::XML');
    my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');

    # get new StatID
    my $StatID = 1;
    my @Keys   = $XMLObject->XMLHashSearch(
        Type => 'Stats',
    );
    if (@Keys) {
        my @SortKeys = sort { $a <=> $b } @Keys;
        $StatID = $SortKeys[-1] + 1;
    }

    # requesting current time stamp
    my $TimeStamp = $DateTimeObject->ToString();

    # meta tags
    my $StatNumber = $StatID + $Kernel::OM->Get('Kernel::Config')->Get('Stats::StatsStartNumber');

    my %MetaData = (
        Created => [
            { Content => $TimeStamp },
        ],
        CreatedBy => [
            { Content => $Param{UserID} },
        ],
        Changed => [
            { Content => $TimeStamp },
        ],
        ChangedBy => [
            { Content => $Param{UserID} },
        ],
        Valid => [
            { Content => 1 },
        ],
        StatNumber => [
            { Content => $StatNumber },
        ],
    );

    # start new stats record
    my @XMLHash = (
        { otrs_stats => [ \%MetaData ] },
    );
    my $Success = $XMLObject->XMLHashAdd(
        Type    => 'Stats',
        Key     => $StatID,
        XMLHash => \@XMLHash,
    );
    if ( !$Success ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Can not add a new Stat!',
        );
        return;
    }

    $Kernel::OM->Get('Kernel::System::Cache')->CleanUp(
        Type => 'Stats',
    );

    return $StatID;
}

=head2 StatsGet()

get a hash ref of the stats you need

    my $HashRef = $StatsObject->StatsGet(
        StatID             => '123',
        NoObjectAttributes => 1,       # optional
    );

=cut

sub StatsGet {
    my ( $Self, %Param ) = @_;

    # check necessary data
    if ( !$Param{StatID} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need StatID!'
        );
    }

    $Param{NoObjectAttributes} = $Param{NoObjectAttributes} ? 1 : 0;

    # get cache object
    my $CacheObject = $Kernel::OM->Get('Kernel::System::Cache');

    my $CacheKey = "StatsGet::StatID::$Param{StatID}::NoObjectAttributes::$Param{NoObjectAttributes}";

    my $Cache = $CacheObject->Get(
        Type => 'Stats',
        Key  => $CacheKey,

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );
    return $Cache if ref $Cache eq 'HASH';

    # get hash from storage
    my @XMLHash = $Kernel::OM->Get('Kernel::System::XML')->XMLHashGet(
        Type => 'Stats',
        Key  => $Param{StatID},
    );

    if ( !$XMLHash[0] ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Can't get StatsID $Param{StatID}!",
        );
        return;
    }

    my %Stat;
    my $StatsXML = $XMLHash[0]->{otrs_stats}->[1];

    # process all strings
    $Stat{StatID} = $Param{StatID};
    for my $Key (
        qw(Title Object File Description SumRow SumCol StatNumber
        Cache StatType Valid ObjectModule CreatedBy ChangedBy Created Changed
        ShowAsDashboardWidget
        )
        )
    {
        if ( defined $StatsXML->{$Key}->[1]->{Content} ) {
            $Stat{$Key} = $StatsXML->{$Key}->[1]->{Content};
        }
    }

    # time zone
    if ( defined $StatsXML->{TimeZone}->[1]->{Content} ) {

        # Check if stored time zone is valid. It can happen stored time zone is still an old-style offset. Otherwise,
        #   fall back to the system time zone. Please see bug#13373 for more information.
        if ( Kernel::System::DateTime->IsTimeZoneValid( TimeZone => $StatsXML->{TimeZone}->[1]->{Content} ) ) {
            $Stat{TimeZone} = $StatsXML->{TimeZone}->[1]->{Content};
        }
        else {
            $Stat{TimeZone} = Kernel::System::DateTime->OTRSTimeZoneGet();
        }
    }

    # process all arrays
    KEY:
    for my $Key (qw(Permission Format GraphSize)) {
        next KEY if !$StatsXML->{$Key}->[1]->{Content};

        $Stat{$Key} = ();
        for my $Index ( 1 .. $#{ $StatsXML->{$Key} } ) {
            push @{ $Stat{$Key} }, $StatsXML->{$Key}->[$Index]->{Content};
        }
    }

    if ( $Stat{ObjectModule} ) {
        $Stat{ObjectBehaviours} = $Self->GetObjectBehaviours(
            ObjectModule => $Stat{ObjectModule},
        );
    }

    # get the configuration elements of the dynamic stats
    # %Allowed is used to avoid double selection in different forms
    my %Allowed;
    my %TimeAllowed;
    my $TimeElement = $Kernel::OM->Get('Kernel::Config')->Get('Stats::TimeElement') || 'Time';

    return \%Stat if !$Stat{Object};

    $Stat{ObjectName} = $Self->GetObjectName(
        ObjectModule => $Stat{ObjectModule},
    );

    if ( $Param{NoObjectAttributes} ) {

        $CacheObject->Set(
            Type  => 'Stats',
            Key   => $CacheKey,
            Value => \%Stat,
            TTL   => 24 * 60 * 60,

            # Don't store complex structure in memory as it will be modified later.
            CacheInMemory => 0,
        );

        return \%Stat;
    }

    KEY:
    for my $Key (qw(UseAsXvalue UseAsValueSeries UseAsRestriction)) {

        # @StatAttributesSimplified give you arrays without undef array elements
        my @StatAttributesSimplified;

        # get the attributes of the object
        my @ObjectAttributes = $Self->GetStatsObjectAttributes(
            ObjectModule => $Stat{ObjectModule},
            Use          => $Key,
        );

        next KEY if !@ObjectAttributes;

        ATTRIBUTE:
        for my $Attribute (@ObjectAttributes) {
            my $Element = $Attribute->{Element};
            if ( $Attribute->{Block} eq 'Time' ) {
                if ( $Key eq 'UseAsValueSeries' ) {
                    if ( $Allowed{$Element} && $Allowed{$Element} == 1 ) {
                        $Allowed{$Element}     = 0;
                        $TimeAllowed{$Element} = 1;
                    }
                    else {
                        $Allowed{$Element} = 1;
                    }
                }
                elsif ( $Key eq 'UseAsRestriction' ) {
                    if ( $TimeAllowed{$Element} && $TimeAllowed{$Element} == 1 ) {
                        $Allowed{$Element} = 1;
                    }
                    else {
                        $Allowed{$Element} = 0;
                    }
                }
            }
            next ATTRIBUTE if $Allowed{$Element};

            if ( $StatsXML->{$Key} ) {
                my @StatAttributes = @{ $StatsXML->{$Key} };
                if ( !$StatAttributes[0] ) {
                    shift @StatAttributes;
                }

                REF:
                for my $Ref (@StatAttributes) {
                    if ( !defined $Attribute->{Translation} ) {
                        $Attribute->{Translation} = 1;
                    }

                    next REF
                        if !(
                        $Element
                        && $Ref->{Element}
                        && $Element eq $Ref->{Element}
                        );

                    # if selected elements exit, add the information to the StatAttributes
                    $Attribute->{Selected} = 1;
                    if ( $Ref->{Fixed} ) {
                        $Attribute->{Fixed} = 1;
                    }

                    for my $Index ( 1 .. $#{ $Ref->{SelectedValues} } ) {
                        push @{ $Attribute->{SelectedValues} }, $Ref->{SelectedValues}->[$Index]->{Content};
                    }

                    if ( $Attribute->{Block} eq 'Time' ) {

                        # settings for working with time elements
                        for my $TimeKey (
                            qw(TimeStop TimeStart TimeRelativeUnit
                            TimeRelativeCount TimeRelativeUpcomingCount TimeScaleCount
                            )
                            )
                        {
                            if ( defined $Ref->{$TimeKey} && ( !$Attribute->{$TimeKey} || $Ref->{Fixed} ) ) {
                                $Attribute->{$TimeKey} = $Ref->{$TimeKey};
                            }
                        }

                        # set a default value for the time relative upcoming count field
                        $Attribute->{TimeRelativeUpcomingCount} //= 0;
                    }

                    $Allowed{$Element} = 1;
                }
            }

            push @StatAttributesSimplified, $Attribute;

        }

        $Stat{$Key} = \@StatAttributesSimplified;
    }

    $CacheObject->Set(
        Type  => 'Stats',
        Key   => $CacheKey,
        Value => \%Stat,
        TTL   => 24 * 60 * 60,

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );

    return \%Stat;
}

=head2 StatsUpdate()

update a stat

    $StatsObject->StatsUpdate(
        StatID => '123',
        Hash   => \%Hash,
        UserID => $UserID,
    );

=cut

sub StatsUpdate {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "Need $Needed.",
            );
            return;
        }
    }

    # declaration of the hash
    my %StatXML;

    # check necessary data
    if ( !$Param{StatID} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need StatID!'
        );
    }

    # requesting stats reference
    my $StatOld = $Self->StatsGet( StatID => $Param{StatID} );
    if ( !$StatOld ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  =>
                "Can't get stats, perhaps you have an invalid stats id! (StatsID => $Param{StatID})"
        );
        return;
    }

    # declare variable
    my $StatNew = $Param{Hash};

    # a delete function can be the better solution
    for my $Key (qw(UseAsXvalue UseAsValueSeries UseAsRestriction)) {
        for my $Data ( @{ $StatOld->{$Key} } ) {
            if ( !$Data->{Selected} ) {
                $Data = undef;
            }
        }
    }

    # adopt changes
    for my $Key ( sort keys %{$StatNew} ) {
        $StatOld->{$Key} = $StatNew->{$Key};
    }

    KEY:
    for my $Key ( sort keys %{$StatOld} ) {

        # Don't store the behaviour data
        next KEY if $Key eq 'ObjectBehaviours';

        if ( $Key eq 'UseAsXvalue' || $Key eq 'UseAsValueSeries' || $Key eq 'UseAsRestriction' ) {
            my $Index = 0;
            REF:
            for my $Ref ( @{ $StatOld->{$Key} } ) {
                next REF if !$Ref;

                $Index++;
                $StatXML{$Key}->[$Index]->{Element} = $Ref->{Element};
                $StatXML{$Key}->[$Index]->{Fixed}   = $Ref->{Fixed};
                my $SubIndex = 0;
                for my $Value ( @{ $Ref->{SelectedValues} } ) {
                    $SubIndex++;
                    $StatXML{$Key}->[$Index]->{SelectedValues}->[$SubIndex]->{Content} = $Value;
                }

                # stetting for working with time elements
                for my $TimeKey (
                    qw(TimeStop TimeStart TimeRelativeUnit TimeRelativeCount TimeRelativeUpcomingCount TimeScaleCount)
                    )
                {
                    if ( defined $Ref->{$TimeKey} ) {
                        $StatXML{$Key}->[$Index]->{$TimeKey} = $Ref->{$TimeKey};
                    }
                }
            }
        }
        elsif ( ref $StatOld->{$Key} eq 'ARRAY' ) {
            for my $Index ( 0 .. $#{ $StatOld->{$Key} } ) {
                $StatXML{$Key}->[$Index]->{Content} = $StatOld->{$Key}->[$Index];
            }
        }
        else {
            if ( defined $StatOld->{$Key} ) {
                $StatXML{$Key}->[1]->{Content} = $StatOld->{$Key};
            }
        }
    }

    # get datetime object
    my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');

    # meta tags
    $StatXML{Changed}->[1]->{Content}   = $DateTimeObject->ToString();
    $StatXML{ChangedBy}->[1]->{Content} = $Param{UserID};

    # get xml object
    my $XMLObject = $Kernel::OM->Get('Kernel::System::XML');

    # please don't change the functionality of XMLHashDelete and XMLHashAdd
    # into the new function XMLHashUpdate, there is an incompatibility.
    # Perhaps there are intricacies because of the 'Array[0] = undef' definition

    # delete the old record
    my $Success = $XMLObject->XMLHashDelete(
        Type => 'Stats',
        Key  => $Param{StatID},
    );
    if ( !$Success ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Can't delete XMLHash!"
        );
        return;
    }

    # delete cache
    $Self->_DeleteCache( StatID => $Param{StatID} );

    my @Array = (
        {
            otrs_stats => [ \%StatXML ],
        },
    );

    # add the revised record
    $Success = $XMLObject->XMLHashAdd(
        Type    => 'Stats',
        Key     => $Param{StatID},
        XMLHash => \@Array
    );
    if ( !$Success ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Can't add XMLHash!"
        );
        return;
    }

    $Kernel::OM->Get('Kernel::System::Cache')->CleanUp(
        Type => 'Stats',
    );

    return 1;
}

=head2 StatsDelete()

delete a stats

    $StatsObject->StatsDelete( StatID => '123' );

=cut

sub StatsDelete {
    my ( $Self, %Param ) = @_;

    # check necessary data
    if ( !$Param{StatID} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need StatID!'
        );
    }

    # delete the record
    my $Success = $Kernel::OM->Get('Kernel::System::XML')->XMLHashDelete(
        Type => 'Stats',
        Key  => $Param{StatID},
    );

    # error handling
    if ( !$Success ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Can't delete XMLHash!",
        );
        return;
    }

    # delete cache
    $Self->_DeleteCache( StatID => $Param{StatID} );

    # get main object
    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');

    # get list of installed stats files
    my @StatsFileList = $MainObject->DirectoryRead(
        Directory => $Self->{StatsTempDir},
        Filter    => '*.xml.installed',
    );

    # delete the .installed file in temp dir
    FILE:
    for my $File ( sort @StatsFileList ) {

        # read file content
        my $StatsIDRef = $MainObject->FileRead(
            Location => $File,
        );

        next FILE if !$StatsIDRef;
        next FILE if ref $StatsIDRef ne 'SCALAR';
        next FILE if !${$StatsIDRef};

        next FILE if ${$StatsIDRef} ne $Param{StatID};

        # delete .installed file
        $MainObject->FileDelete(
            Location => $File,
        );
    }

    # add log message
    $Kernel::OM->Get('Kernel::System::Log')->Log(
        Priority => 'notice',
        Message  => "Delete stats (StatsID = $Param{StatID})",
    );

    $Kernel::OM->Get('Kernel::System::Cache')->CleanUp(
        Type => 'Stats',
    );

    return 1;
}

=head2 StatsListGet()

fetches all statistics that the current user may see

    my $StatsRef = $StatsObject->StatsListGet(
        AccessRw => 1,          # Optional, indicates that user may see all statistics
        UserID   => $UserID,
    );

    Returns

    {
        6 => {
            Title => "Title of stat",
            # ...
        }
    }

=cut

sub StatsListGet {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "Need $Needed.",
            );
            return;
        }
    }

    my @SearchResult;

    # get cache object
    my $CacheObject = $Kernel::OM->Get('Kernel::System::Cache');

    # Only cache the XML search as we need to filter based on user permissions later
    my $CacheKey = 'StatsListGet::XMLSearch';
    my $Cache    = $CacheObject->Get(
        Type => 'Stats',
        Key  => $CacheKey,

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );

    # Do we have a cache available?
    if ( ref $Cache eq 'ARRAY' ) {
        @SearchResult = @{$Cache};
    }
    else {

        # get xml object
        my $XMLObject = $Kernel::OM->Get('Kernel::System::XML');

        # No cache. Is there stats data yet?
        if ( !( @SearchResult = $XMLObject->XMLHashSearch( Type => 'Stats' ) ) ) {

            # Import sample stats
            $Self->_AutomaticSampleImport(
                UserID => $Param{UserID},
            );

            # Load stats again
            return if !( @SearchResult = $XMLObject->XMLHashSearch( Type => 'Stats' ) );
        }
        $CacheObject->Set(
            Type  => 'Stats',
            Key   => $CacheKey,
            Value => \@SearchResult,
            TTL   => 24 * 60 * 60,

            # Don't store complex structure in memory as it will be modified later.
            CacheInMemory => 0,
        );

    }

    # get user groups
    my %GroupList = $Kernel::OM->Get('Kernel::System::Group')->PermissionUserGet(
        UserID => $Param{UserID},
        Type   => 'ro',
    );

    my %Result;

    for my $StatID (@SearchResult) {

        my $Stat = $Self->StatsGet(
            StatID             => $StatID,
            NoObjectAttributes => 1,
        );

        my $UserPermission = 0;
        if ( $Param{AccessRw} || $Param{UserID} == 1 ) {

            $UserPermission = 1;
        }
        elsif ( $Stat->{Valid} ) {

            GROUPID:
            for my $GroupID ( @{ $Stat->{Permission} } ) {

                next GROUPID if !$GroupID;
                next GROUPID if !$GroupList{$GroupID};

                $UserPermission = 1;

                last GROUPID;
            }
        }

        if ( $UserPermission == 1 ) {
            $Result{$StatID} = $Stat;
        }
    }

    return \%Result;
}

=head2 GetStatsList()

lists all stats id's

    my $ArrayRef = $StatsObject->GetStatsList(
        AccessRw  => 1,                             # optional, indicates that user may see all statistics
        OrderBy   => 'ID' || 'Title' || 'Object',   # optional
        Direction => 'ASC' || 'DESC',               # optional
        UserID    => $UserID,
    );

=cut

sub GetStatsList {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "Need $Needed.",
            );
            return;
        }
    }

    $Param{OrderBy}   ||= 'ID';
    $Param{Direction} ||= 'ASC';

    my %ResultHash = %{ $Self->StatsListGet(%Param) || {} };

    my @SortArray;

    if ( $Param{OrderBy} eq 'ID' ) {
        @SortArray = sort { $a <=> $b } keys %ResultHash;
    }
    else {
        @SortArray = sort { $ResultHash{$a}->{ $Param{OrderBy} } cmp $ResultHash{$b}->{ $Param{OrderBy} } }
            keys %ResultHash;
    }
    if ( $Param{Direction} eq 'DESC' ) {
        @SortArray = reverse @SortArray;
    }

    return \@SortArray;
}

=head2 SumBuild()

build sum in x or/and y axis

    $StatArray = $StatsObject->SumBuild(
        Array  => \@Result,
        SumRow => 1,
        SumCol => 0,
    );

=cut

sub SumBuild {
    my ( $Self, %Param ) = @_;

    my @Data = @{ $Param{Array} };

    # add sum y
    if ( $Param{SumCol} ) {

        push @{ $Data[1] }, Translatable('Sum');

        for my $Index1 ( 2 .. $#Data ) {

            my $Sum = 0;
            INDEX2:
            for my $Index2 ( 1 .. $#{ $Data[$Index1] } ) {

                next INDEX2 if !$Data[$Index1][$Index2];

                # extract the value
                my $Value = $Data[$Index1][$Index2];

                # clean the string
                $Value =~ s{ \A \s+ }{}xms;
                $Value =~ s{ \s+ \z }{}xms;
                $Value =~ s{ , }{.}xms;

                # add value to summary
                if ( $Value =~ m{^-?\d+(\.\d+)?$} ) {
                    $Sum += $Value;
                }
            }

            push @{ $Data[$Index1] }, $Sum;
        }
    }

    # add sum x
    if ( $Param{SumRow} ) {

        my @SumRow = ();
        $SumRow[0] = 'Sum';

        for my $Index1 ( 2 .. $#Data ) {

            INDEX2:
            for my $Index2 ( 1 .. $#{ $Data[$Index1] } ) {

                # make sure we have a value to add
                if ( !defined $Data[$Index1][$Index2] ) {
                    $Data[$Index1][$Index2] = 0;
                }

                # extract the value
                my $Value = $Data[$Index1][$Index2];

                # clean the string
                $Value =~ s{ \A \s+ }{}xms;
                $Value =~ s{ \s+ \z }{}xms;
                $Value =~ s{ , }{.}xms;

                # add value to summary
                if ( $Value =~ m{^-?\d+(\.\d+)?$} ) {
                    $SumRow[$Index2] += $Value;
                }
            }
        }

        push @Data, \@SumRow;
    }
    return @Data;
}

=head2 GetStatsObjectAttributes()

Get all attributes from the object in dependence of the use

    my %ObjectAttributes = $StatsObject->GetStatsObjectAttributes(
        ObjectModule => 'Ticket',
        Use          => 'UseAsXvalue' || 'UseAsValueSeries' || 'UseAsRestriction',
    );

=cut

sub GetStatsObjectAttributes {
    my ( $Self, %Param ) = @_;

    # check needed params
    for my $Needed (qw(ObjectModule Use)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!"
            );
            return;
        }
    }

    # load module
    my $ObjectModule = $Param{ObjectModule};
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);
    my $StatObject = $ObjectModule->new( %{$Self} );
    return if !$StatObject;
    return if !$StatObject->can('GetObjectAttributes');

    # load attributes
    my @ObjectAttributesRaw = $StatObject->GetObjectAttributes();

    # build the objectattribute array
    my @ObjectAttributes;
    for my $HashRef (@ObjectAttributesRaw) {
        if ( $HashRef->{ $Param{Use} } ) {
            delete $HashRef->{UseAsXvalue};
            delete $HashRef->{UseAsValueSeries};
            delete $HashRef->{UseAsRestriction};

            push @ObjectAttributes, $HashRef;
        }
    }

    return @ObjectAttributes;
}

=head2 GetStaticFiles()

Get all static files

    my $FileHash = $StatsObject->GetStaticFiles(
        OnlyUnusedFiles => 1 || 0,  # optional default 0
        UserID          => $UserID,
    );

=cut

sub GetStaticFiles {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "Need $Needed.",
            );
            return;
        }
    }

    my $Directory = $Kernel::OM->Get('Kernel::Config')->Get('Home');
    if ( $Directory !~ m{^.*\/$}x ) {
        $Directory .= '/';
    }
    $Directory .= 'Kernel/System/Stats/Static/';

    if ( !opendir( DIR, $Directory ) ) {    ## no critic
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Can not open Directory: $Directory",
        );
        return ();
    }

    my %StaticFiles;
    if ( $Param{OnlyUnusedFiles} ) {

        # get all Stats from the db
        my $Result = $Self->GetStatsList(
            UserID => $Param{UserID},
        );

        if ( defined $Result ) {
            for my $StatID ( @{$Result} ) {
                my $Data = $Self->StatsGet(
                    StatID             => $StatID,
                    UserID             => $Param{UserID},
                    NoObjectAttributes => 1,
                );

                # check witch one are static statistics
                if ( $Data->{File} && $Data->{StatType} eq 'static' ) {
                    $StaticFiles{ $Data->{File} } = 1;
                }
            }
        }
    }

    # read files
    my %Filelist;

    DIRECTORY:
    while ( defined( my $Filename = readdir DIR ) ) {
        next DIRECTORY if $Filename eq '.';
        next DIRECTORY if $Filename eq '..';
        if ( $Filename =~ m{^(.*)\.pm$}x ) {
            if ( !defined $StaticFiles{$1} ) {
                $Filelist{$1} = $1;
            }
        }
    }
    closedir(DIR);

    return \%Filelist;
}

=head2 GetDynamicFiles()

Get all static objects

    my $FileHash = $StatsObject->GetDynamicFiles();

=cut

sub GetDynamicFiles {
    my $Self = shift;

    # get config object
    my $ConfigObject = $Kernel::OM->Get('Kernel::Config');

    my %Filelist = %{ $ConfigObject->Get('Stats::DynamicObjectRegistration') };
    OBJECT:
    for my $Object ( sort keys %Filelist ) {
        if ( !$Filelist{$Object} ) {
            delete $Filelist{$Object};
            next OBJECT;
        }
        $Filelist{$Object} = $Self->GetObjectName(
            ObjectModule => $Filelist{$Object}->{Module},
        );
    }
    return if !%Filelist;

    return \%Filelist;
}

=head2 GetObjectName()

Get the name of a dynamic object

    my $ObjectName = $StatsObject->GetObjectName(
        ObjectModule => 'Kernel::System::Stats::Dynamic::TicketList',
    );

=cut

sub GetObjectName {
    my ( $Self, %Param ) = @_;
    my $Module = $Param{ObjectModule};

    # check if it is cached
    return $Self->{'Cache::ObjectName'}->{$Module} if $Self->{'Cache::ObjectName'}->{$Module};

    # load module, return if module does not exist
    # (this is important when stats are uninstalled, see also bug# 4269)
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($Module);

    # get name
    my $StatObject = $Module->new( %{$Self} );
    return if !$StatObject;
    return if !$StatObject->can('GetObjectName');

    my $Name = $StatObject->GetObjectName();

    # cache the result
    $Self->{'Cache::ObjectName'}->{$Module} = $Name;

    return $Name;
}

=head2 GetObjectBehaviours()

get behaviours that a statistic supports

    my $Behaviours = $StatsObject->GetObjectBehaviours(
        ObjectModule => 'Kernel::System::Stats::Dynamic::TicketList',
    );

    returns

    {
        ProvidesDashboardWidget => 1,
        # ...
    }

=cut

sub GetObjectBehaviours {
    my ( $Self, %Param ) = @_;
    my $Module = $Param{ObjectModule};

    # check if it is cached
    if ( $Self->{'Cache::ObjectBehaviours'}->{$Module} ) {
        return $Self->{'Cache::ObjectBehaviours'}->{$Module};
    }

    # load module, return if module does not exist
    # (this is important when stats are uninstalled, see also bug# 4269)
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($Module);

    my $StatObject = $Module->new( %{$Self} );
    return if !$StatObject;
    return if !$StatObject->can('GetObjectBehaviours');

    my %ObjectBehaviours = $StatObject->GetObjectBehaviours();

    # cache the result
    $Self->{'Cache::ObjectBehaviours'}->{$Module} = \%ObjectBehaviours;

    return \%ObjectBehaviours;
}

=head2 ObjectFileCheck()

AT THE MOMENT NOT USED

check readable object file

    my $ObjectFileCheck = $StatsObject->ObjectFileCheck(
        Type => 'static',
        Name => 'NewTickets',
    );

=cut

sub ObjectFileCheck {
    my ( $Self, %Param ) = @_;

    my $Directory = $Kernel::OM->Get('Kernel::Config')->Get('Home');
    if ( $Directory !~ m{^.*\/$}x ) {
        $Directory .= '/';
    }
    if ( $Param{Type} eq 'static' ) {
        $Directory .= 'Kernel/System/Stats/Static/' . $Param{Name} . '.pm';
    }
    elsif ( $Param{Type} eq 'dynamic' ) {
        $Directory .= 'Kernel/System/Stats/Dynamic/' . $Param{Name} . '.pm';
    }

    return 1 if -r $Directory;
    return;
}

=head2 ObjectModuleCheck()

Check the object module.

    my $ObjectModuleCheck = $StatsObject->ObjectModuleCheck(
        StatType                     => 'static',
        ObjectModule                 => 'Kernel::System::Stats::Static::StateAction',
        CheckAlreadyUsedStaticObject => 1,                                             # optional
    );

Returns true on success and false on error.

=cut

sub ObjectModuleCheck {
    my ( $Self, %Param ) = @_;

    return if !$Param{StatType} || !$Param{ObjectModule};
    return if $Param{StatType} ne 'static' && $Param{StatType} ne 'dynamic';

    my $CheckFileLocation = 'Kernel::System::Stats::' . ucfirst $Param{StatType};
    my $CheckPackageName  = '[A-Z_a-z][0-9A-Z_a-z]*';
    return if $Param{ObjectModule} !~ m{ \A $CheckFileLocation (?: ::$CheckPackageName)+ \z }xms;

    my $ObjectName = [ split( m{::}, $Param{ObjectModule} ) ]->[-1];
    return if !$ObjectName;

    my @RequiredObjectFunctions;

    if ( $Param{StatType} eq 'static' ) {

        @RequiredObjectFunctions = (
            'Param',
            'Run',
        );

        my $StaticFiles = $Self->GetStaticFiles(
            OnlyUnusedFiles => $Param{CheckAlreadyUsedStaticObject},
            UserID          => 1,
        );

        if ( $ObjectName && !$StaticFiles->{$ObjectName} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Static object $ObjectName doesn't exist or static object already in use!",
            );
            return;
        }
    }
    else {

        @RequiredObjectFunctions = (
            'GetObjectName',
            'GetObjectAttributes',
        );

        # Check if the given Object exists in the statistic object registartion.
        my $DynamicFiles = $Self->GetDynamicFiles();

        if ( !$DynamicFiles->{$ObjectName} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Object $ObjectName doesn't exist!"
            );
            return;
        }
    }

    my $ObjectModule = $Param{ObjectModule};
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);

    my $StatObject = $ObjectModule->new( %{$Self} );
    return if !$StatObject;

    # Check for the required object functions.
    for my $RequiredObjectFunction (@RequiredObjectFunctions) {
        return if !$StatObject->can($RequiredObjectFunction);
    }

    # Special check for some fucntions in the dynamic statistic object.
    if ( $Param{StatType} eq 'dynamic' ) {
        return if !$StatObject->can('GetStatTable') && !$StatObject->can('GetStatElement');
    }

    return 1;
}

=head2 Export()

get content from stats for export

    my $ExportFile = $StatsObject->Export(
        StatID           => '123',
        ExportStatNumber => 1 || 0,     # optional, only useful move statistics from the test system to the productive system
    );

=cut

sub Export {
    my ( $Self, %Param ) = @_;

    if ( !$Param{StatID} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Export: Need StatID!'
        );
        return;
    }

    # get xml object
    my $XMLObject = $Kernel::OM->Get('Kernel::System::XML');

    my @XMLHash = $XMLObject->XMLHashGet(
        Type => 'Stats',
        Key  => $Param{StatID},
    );
    my $StatsXML = $XMLHash[0]->{otrs_stats}->[1];

    my %File;
    $File{Filename} = $Self->StringAndTimestamp2Filename(
        String => $StatsXML->{Title}->[1]->{Content},
    );
    $File{Filename} .= '.xml';

    # Delete not needed and useful keys from the stats xml.
    for my $Key (qw(Changed ChangedBy Created CreatedBy StatID)) {
        delete $StatsXML->{$Key};
    }
    if ( !$Param{ExportStatNumber} ) {
        delete $StatsXML->{StatNumber};
    }

    # wrapper to change ids in used spelling
    # wrap permissions
    PERMISSION:
    for my $ID ( @{ $StatsXML->{Permission} } ) {
        next PERMISSION if !$ID;
        my $Name = $Kernel::OM->Get('Kernel::System::Group')->GroupLookup( GroupID => $ID->{Content} );
        next PERMISSION if !$Name;
        $ID->{Content} = $Name;
    }

    # wrap object dependend ids
    if ( $StatsXML->{Object}->[1]->{Content} ) {

        # load module
        my $ObjectModule = $StatsXML->{ObjectModule}->[1]->{Content};
        return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);
        my $StatObject = $ObjectModule->new( %{$Self} );
        return if !$StatObject;

        if ( $StatObject->can('ExportWrapper') ) {
            $StatsXML = $StatObject->ExportWrapper(
                %{$StatsXML},
            );
        }
    }

    # convert hash to string
    $File{Content} = $XMLObject->XMLHash2XML(
        {
            otrs_stats => [
                undef,
                $StatsXML,
            ],
        },
    );

    return \%File;
}

=head2 Import()

import a stats from xml file

    my $StatID = $StatsObject->Import(
        UserID  => $UserID,
        Content => $UploadStuff{Content},
    );

=cut

sub Import {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID Content)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "Need $Needed.",
            );
            return;
        }
    }

    # get xml object
    my $XMLObject = $Kernel::OM->Get('Kernel::System::XML');

    my @XMLHash = $XMLObject->XMLParse2XMLHash( String => $Param{Content} );

    if ( !$XMLHash[0] ) {
        shift @XMLHash;
    }
    my $StatsXML = $XMLHash[0]->{otrs_stats}->[1];

    # Get new StatID
    my @Keys = $XMLObject->XMLHashSearch(
        Type => 'Stats',
    );

    # check if the required elements are available
    for my $Element (qw( Description Format Object ObjectModule Permission StatType SumCol SumRow Title Valid)) {
        if ( !defined $StatsXML->{$Element}->[1]->{Content} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Can't import Stat, because the required element $Element is not available!"
            );
            return;
        }
    }

    my $ObjectModuleCheck = $Self->ObjectModuleCheck(
        StatType                     => $StatsXML->{StatType}->[1]->{Content},
        ObjectModule                 => $StatsXML->{ObjectModule}->[1]->{Content},
        CheckAlreadyUsedStaticObject => 1,
    );

    return if !$ObjectModuleCheck;

    my $ObjectModule = $StatsXML->{ObjectModule}->[1]->{Content};
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);

    my $StatObject = $ObjectModule->new( %{$Self} );
    return if !$StatObject;

    my $ObjectName = [ split( m{::}, $StatsXML->{ObjectModule}->[1]->{Content} ) ]->[-1];
    if ( $StatsXML->{StatType}->[1]->{Content} eq 'static' ) {
        $StatsXML->{File}->[1]->{Content} = $ObjectName;
    }
    else {
        $StatsXML->{Object}->[1]->{Content} = $ObjectName;
    }

    my $ConfigObject = $Kernel::OM->Get('Kernel::Config');

    # if-clause if a stat-xml includes a StatNumber
    my $StatID = 1;
    if ( $StatsXML->{StatNumber} ) {
        my $XMLStatsID = $StatsXML->{StatNumber}->[1]->{Content} - $ConfigObject->Get('Stats::StatsStartNumber');
        for my $Key (@Keys) {
            if ( $Key eq $XMLStatsID ) {
                $Kernel::OM->Get('Kernel::System::Log')->Log(
                    Priority => 'error',
                    Message  => "Can't import StatNumber $Key, because this StatNumber is already used!"
                );
                return;
            }
        }
        $StatID = $XMLStatsID;
    }

    # if no stats number available use this function
    else {
        my @SortKeys = sort { $a <=> $b } @Keys;
        if (@SortKeys) {
            $StatID = $SortKeys[-1] + 1;
        }
    }

    # requesting current time stamp
    my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');

    # meta tags
    $StatsXML->{Created}->[1]->{Content}    = $DateTimeObject->ToString();
    $StatsXML->{CreatedBy}->[1]->{Content}  = $Param{UserID};
    $StatsXML->{Changed}->[1]->{Content}    = $DateTimeObject->ToString();
    $StatsXML->{ChangedBy}->[1]->{Content}  = $Param{UserID};
    $StatsXML->{StatNumber}->[1]->{Content} = $StatID + $ConfigObject->Get('Stats::StatsStartNumber');

    # wrapper to change used spelling in ids
    # wrap permissions
    my %Groups = $Kernel::OM->Get('Kernel::System::Group')->GroupList( Valid => 1 );

    NAME:
    for my $Name ( @{ $StatsXML->{Permission} } ) {
        next NAME if !$Name;

        my $Flag = 1;
        ID:
        for my $ID ( sort keys %Groups ) {
            if ( $Groups{$ID} eq $Name->{Content} ) {
                $Name->{Content} = $ID;
                $Flag = 0;
                last ID;
            }
        }
        if ($Flag) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Can't find the permission (group) $Name->{Content}!"
            );
            $Name = undef;
        }
    }

    # wrap object dependend ids
    if ( $StatObject->can('ImportWrapper') ) {
        $StatsXML = $StatObject->ImportWrapper( %{$StatsXML} );
    }

    return if !$XMLObject->XMLHashAdd(
        Type    => 'Stats',
        Key     => $StatID,
        XMLHash => [
            {
                otrs_stats => [
                    undef,
                    $StatsXML,
                ],
            },
        ],
    );

    $Kernel::OM->Get('Kernel::System::Cache')->CleanUp(
        Type => 'Stats',
    );

    return $StatID;
}

=head2 GetParams()

    get all edit params from stats for view

    my $Params = $StatsObject->GetParams( StatID => '123' );

=cut

sub GetParams {
    my ( $Self, %Param ) = @_;

    if ( !$Param{StatID} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need StatID!'
        );
        return;
    }

    my $Stat = $Self->StatsGet( StatID => $Param{StatID} );

    # static
    # don't remove this if clause, because is required for otrs.GenerateStats.pl
    my @Params;
    if ( $Stat->{StatType} eq 'static' ) {

        # load static modul
        my $ObjectModule = $Stat->{ObjectModule};
        return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);
        my $StatObject = $ObjectModule->new( %{$Self} );
        return if !$StatObject;
        return if !$StatObject->can('Param');

        # get params
        @Params = $StatObject->Param();
    }

    return \@Params;
}

=head2 StatsRun()

run a statistic.

    my $StatArray = $StatsObject->StatsRun(
        StatID     => '123',
        GetParam   => \%GetParam,
        Preview    => 1,            # optional, return fake data for preview (only for dynamic stats)
        UserID     => $UserID,
    );

=cut

sub StatsRun {
    my ( $Self, %Param ) = @_;

    # check needed params
    for my $Needed (qw(StatID GetParam UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    my $Stat     = $Self->StatsGet( StatID => $Param{StatID} );
    my %GetParam = %{ $Param{GetParam} };
    my @Result;

    # Perform calculations on the slave DB, if configured.
    local $Kernel::System::DB::UseSlaveDB = 1;

    # get data if it is a static stats
    if ( $Stat->{StatType} eq 'static' ) {

        return if $Param{Preview};    # not supported for static stats

        @Result = $Self->_GenerateStaticStats(
            ObjectModule => $Stat->{ObjectModule},
            GetParam     => $Param{GetParam},
            Title        => $Stat->{Title},
            StatID       => $Stat->{StatID},
            Cache        => $Stat->{Cache},
            UserID       => $Param{UserID},
        );
    }

    # get data if it is a dynaymic stats
    elsif ( $Stat->{StatType} eq 'dynamic' ) {
        @Result = $Self->_GenerateDynamicStats(
            ObjectModule     => $Stat->{ObjectModule},
            Object           => $Stat->{Object},
            UseAsXvalue      => $GetParam{UseAsXvalue},
            UseAsValueSeries => $GetParam{UseAsValueSeries} || [],
            UseAsRestriction => $GetParam{UseAsRestriction} || [],
            Title            => $Stat->{Title},
            StatID           => $Stat->{StatID},
            TimeZone         => $GetParam{TimeZone},
            Cache            => $Stat->{Cache},
            Preview          => $Param{Preview},
            UserID           => $Param{UserID},
        );
    }

    # Build sum in row or col.
    if ( @Result && ( $Stat->{SumRow} || $Stat->{SumCol} ) && $Stat->{Format} !~ m{^GD::Graph\.*}x ) {
        @Result = $Self->SumBuild(
            Array  => \@Result,
            SumRow => $Stat->{SumRow},
            SumCol => $Stat->{SumCol},
        );
    }

    # Exchange axis if selected.
    if ( $GetParam{ExchangeAxis} ) {
        my @NewStatArray;
        my $Title = $Result[0]->[0];

        shift(@Result);
        for my $Key1 ( 0 .. $#Result ) {
            for my $Key2 ( 0 .. $#{ $Result[0] } ) {
                $NewStatArray[$Key2]->[$Key1] = $Result[$Key1]->[$Key2];
            }
        }
        $NewStatArray[0]->[0] = '';
        unshift( @NewStatArray, [$Title] );
        @Result = @NewStatArray;
    }

    # Translate the column and row description.
    $Self->_ColumnAndRowTranslation(
        StatArrayRef => \@Result,
        StatRef      => $Stat,
        ExchangeAxis => $GetParam{ExchangeAxis},
    );

    return \@Result;
}

=head2 StatsResultCacheCompute()

computes stats results and adds them to the cache.
This can be used to precompute stats data e. g. for dashboard widgets in a cron job.

    my $StatArray = $StatsObject->StatsResultCacheCompute(
        StatID       => '123',
        UserID       => $UserID,            # target UserID
        UserGetParam => \%UserGetParam,     # user settings of non-fixed fields
    );

=cut

sub StatsResultCacheCompute {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(StatID UserGetParam UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    my $Stat = $Self->StatsGet(
        StatID => $Param{StatID},
    );

    my $StatsViewObject = $Kernel::OM->Get('Kernel::Output::HTML::Statistics::View');

    my $StatConfigurationValid = $StatsViewObject->StatsConfigurationValidate(
        Stat   => $Stat,
        Errors => {},
        UserID => $Param{UserID},
    );
    if ( !$StatConfigurationValid ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "This statistic contains configuration errors, skipping.",
        );
        return;
    }

    my %GetParam = eval {
        $StatsViewObject->StatsParamsGet(
            Stat         => $Stat,
            UserGetParam => $Param{UserGetParam},
        );
    };

    if ( $@ || !%GetParam ) {
        my $Errors = ref $@ ? join( "\n", @{$@} ) : $@;
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "The dashboard widget configuration for this user contains errors, skipping: $Errors"
        );
        return;
    }

    # get main object
    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');

    my $DumpString = $MainObject->Dump( \%GetParam );

    my $MD5Sum = $MainObject->MD5sum(
        String => \$DumpString,
    );

    my $CacheKey = "StatsRunCached::$Param{UserID}::$Param{StatID}::$MD5Sum";

    my $Result = $Self->StatsRun(
        StatID   => $Param{StatID},
        GetParam => \%GetParam,
        UserID   => $Param{UserID},
    );

    # Only set/update the cache after computing it, otherwise no cache data
    #   would be available in between.
    return $Kernel::OM->Get('Kernel::System::Cache')->Set(
        Type  => 'StatsRun',
        Key   => $CacheKey,
        Value => $Result,
        TTL   => 24 * 60 * 60,    # cache it for a day, will be overwritten by next function call

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );
}

=head2 StatsResultCacheGet()

gets cached statistic results. Will never run the statistic.
This can be used to fetch cached stats data e. g. for stats widgets in the dashboard.

    my $StatArray = $StatsObject->StatsResultCacheGet(
        StatID       => '123',
        UserID       => $UserID,        # target UserID
        UserGetParam => \%GetParam,
    );

=cut

sub StatsResultCacheGet {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(StatID UserGetParam UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    my $Stat = $Self->StatsGet(
        StatID => $Param{StatID},
    );

    my $StatsViewObject = $Kernel::OM->Get('Kernel::Output::HTML::Statistics::View');

    my $StatConfigurationValid = $StatsViewObject->StatsConfigurationValidate(
        Stat   => $Stat,
        Errors => {},
        UserID => $Param{UserID},
    );
    if ( !$StatConfigurationValid ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "This statistic contains configuration errors, skipping.",
        );
        return;
    }

    my %GetParam = eval {
        $StatsViewObject->StatsParamsGet(
            Stat         => $Stat,
            UserGetParam => $Param{UserGetParam},
            UserID       => $Param{UserID},
        );
    };

    if ( $@ || !%GetParam ) {
        my $Errors = ref $@ ? join( "\n", @{$@} ) : $@;
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "The dashboard widget configuration for this user contains errors, skipping: $Errors"
        );
        return;
    }

    # get main object
    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');

    my $DumpString = $MainObject->Dump( \%GetParam );

    my $MD5Sum = $MainObject->MD5sum(
        String => \$DumpString,
    );

    my $CacheKey = "StatsRunCached::$Param{UserID}::$Param{StatID}::$MD5Sum";

    return $Kernel::OM->Get('Kernel::System::Cache')->Get(
        Type => 'StatsRun',
        Key  => $CacheKey,

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );
}

=head2 StringAndTimestamp2Filename()

builds a filename with a string and a timestamp.
(space will be replaced with _ and - e.g. Title-of-File_2006-12-31_11-59)

    my $Filename = $StatsObject->StringAndTimestamp2Filename(
        String   => 'Title',
        TimeZone => 'Europe/Berlin',    # optional
    );

=cut

sub StringAndTimestamp2Filename {
    my ( $Self, %Param ) = @_;

    if ( !$Param{String} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need String!'
        );
        return;
    }

    my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');
    if ( defined $Param{TimeZone} ) {
        $DateTimeObject->ToTimeZone( TimeZone => $Param{TimeZone} );
    }

    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');
    $Param{String} = $MainObject->FilenameCleanUp(
        Filename => $Param{String},
        Type     => 'Attachment',
    );

    my $Filename = $Param{String} . '_';
    $Filename .= $DateTimeObject->Format( Format => '%Y-%m-%d_%H-%M' );

    if ( defined $Param{TimeZone} ) {
        my $TimeZone = $MainObject->FilenameCleanUp(
            Filename => $Param{TimeZone},
            Type     => 'Attachment',
        );
        $Filename .= '_TimeZone_' . $TimeZone;
    }

    return $Filename;
}

=head2 StatNumber2StatID()

insert the stat number get the stat id

    my $StatID = $StatsObject->StatNumber2StatID(
        StatNumber => 11212,
    );

=cut

sub StatNumber2StatID {
    my ( $Self, %Param ) = @_;

    if ( !$Param{StatNumber} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need StatNumber!',
        );
        return;
    }

    my @Key = $Kernel::OM->Get('Kernel::System::XML')->XMLHashSearch(
        Type => 'Stats',
        What => [ { "[%]{'otrs_stats'}[%]{'StatNumber'}[%]{'Content'}" => $Param{StatNumber} } ],
    );
    if ( @Key && $#Key < 1 ) {
        return $Key[0];
    }

    $Kernel::OM->Get('Kernel::System::Log')->Log(
        Priority => 'error',
        Message  => 'StatNumber invalid!',
    );
    return;
}

=head2 StatsInstall()

installs stats

    my $Result = $StatsObject->StatsInstall(
        FilePrefix => 'FAQ',    # (optional)
        UserID     => $UserID,
    );

=cut

sub StatsInstall {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    # prepare prefix
    $Param{FilePrefix} = $Param{FilePrefix} ? $Param{FilePrefix} . '-' : '';

    # start AutomaticSampleImport if no stats are installed
    $Self->GetStatsList(
        UserID => $Param{UserID},
    );

    # get main object
    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');

    # get list of stats files
    my @StatsFileList = $MainObject->DirectoryRead(
        Directory => $Self->{StatsTempDir},
        Filter    => $Param{FilePrefix} . '*.xml',
    );

    # import the stats
    my $InstalledPostfix = '.installed';
    FILE:
    for my $File ( sort @StatsFileList ) {

        next FILE if !-f $File;
        next FILE if -e $File . $InstalledPostfix;

        # read file content
        my $XMLContentRef = $MainObject->FileRead(
            Location => $File,
        );

        # import stat
        my $StatID = $Self->Import(
            Content => ${$XMLContentRef},
            UserID  => $Param{UserID},
        );

        next FILE if !$StatID;

        # write installed file with stat id
        $MainObject->FileWrite(
            Content  => \$StatID,
            Location => $File . $InstalledPostfix,
        );
    }

    return 1;
}

=head2 StatsUninstall()

uninstalls stats

    my $Result = $StatsObject->StatsUninstall(
        FilePrefix => 'FAQ',    # (optional)
        UserID     => $UserID,
    );

=cut

sub StatsUninstall {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    # prepare prefix
    $Param{FilePrefix} = $Param{FilePrefix} ? $Param{FilePrefix} . '-' : '';

    # get main object
    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');

    # get list of installed stats files
    my @StatsFileList = $MainObject->DirectoryRead(
        Directory => $Self->{StatsTempDir},
        Filter    => $Param{FilePrefix} . '*.xml.installed',
    );

    my @UninstalledObjectNames;

    # delete the stats
    for my $File ( sort @StatsFileList ) {

        # read file content
        my $StatsIDRef = $MainObject->FileRead(
            Location => $File,
        );

        my $Stat = $Self->StatsGet(
            StatID             => ${$StatsIDRef},
            NoObjectAttributes => 1,
        );

        # Add object name from the deleted statistic to the uninstalled object names.
        if ( $Stat->{ObjectModule} ) {
            my $ObjectName = [ split( m{::}, $Stat->{ObjectModule} ) ]->[-1];
            push @UninstalledObjectNames, $ObjectName;
        }

        # delete stats
        $Self->StatsDelete(
            StatID => ${$StatsIDRef},
            UserID => $Param{UserID},
        );
    }

    # Cleanup for all uninstalled object names.
    if (@UninstalledObjectNames) {
        $Self->StatsCleanUp(
            ObjectNames => \@UninstalledObjectNames,
            UserID      => $Param{UserID},
        );
    }

    return 1;
}

=head2 StatsCleanUp()

removed stats with not existing backend file

    my $Result = $StatsObject->StatsCleanUp(
        UserID          => 1,

        ObjectNames     => [ 'Ticket', 'TicketList' ],
        # or
        CheckAllObjects => 1,
    );

=cut

sub StatsCleanUp {
    my ( $Self, %Param ) = @_;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    if ( !$Param{CheckAllObjects} && !IsArrayRefWithData( $Param{ObjectNames} ) ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Need ObjectNames or the CheckAllObjects parameter!",
        );
        return;
    }

    # get a list of all stats
    my $ListRef = $Self->GetStatsList(
        UserID => $Param{UserID},
    );

    return if !$ListRef;
    return if ref $ListRef ne 'ARRAY';

    # get main object
    my $MainObject = $Kernel::OM->Get('Kernel::System::Main');

    my %LookupObjectNames;
    if ( !$Param{CheckAllObjects} ) {
        %LookupObjectNames = map { $_ => 1 } @{ $Param{ObjectNames} };
    }

    STATSID:
    for my $StatsID ( @{$ListRef} ) {

        # get stats
        my $HashRef = $Self->StatsGet(
            StatID             => $StatsID,
            NoObjectAttributes => 1,
        );

        # Cleanup only files given in ObjectNames.
        if ( !$Param{CheckAllObjects} ) {

            my $ObjectName = [ split( m{::}, $HashRef->{ObjectModule} ) ]->[-1];

            next STATSID if !$LookupObjectNames{$ObjectName};
        }

        if (
            IsHashRefWithData($HashRef)
            && $HashRef->{ObjectModule}
            && $MainObject->Require( $HashRef->{ObjectModule} )
            )
        {
            next STATSID;
        }

        # delete stats
        $Self->StatsDelete(
            StatID => $StatsID,
            UserID => $Param{UserID},
        );
    }

    return 1;
}

=begin Internal:

Private functions used by this package (not part of the documented public API).

=end Internal:

=head2 _GenerateStaticStats()

    take the stat configuration and get the stat table

    my @StatArray = $StatsObject->_GenerateStaticStats(
        ObjectModule => $Stat->{ObjectModule},
        GetParam     => $Param{GetParam},
        Title        => $Stat->{Title},
        StatID       => $Stat->{StatID},
        Cache        => $Stat->{Cache},
        UserID       => $UserID,
    );

=cut

sub _GenerateStaticStats {
    my ( $Self, %Param ) = @_;

    # check needed params
    NEED:
    for my $Need (qw(ObjectModule GetParam Title StatID UserID)) {
        next NEED if $Param{$Need};
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Need $Need!"
        );
        return;
    }

    # load static module
    my $ObjectModule = $Param{ObjectModule};
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);
    my $StatObject = $ObjectModule->new( %{$Self} );
    return if !$StatObject;
    return if !$StatObject->can('Run');

    my @Result;
    my %GetParam = %{ $Param{GetParam} };

    # use result cache if configured
    if ( $Param{Cache} ) {
        my $Filename = $Self->_CreateStaticResultCacheFilename(
            GetParam => \%GetParam,
            StatID   => $Param{StatID},
        );

        @Result = $Self->_GetResultCache( Filename => $Filename );
        if (@Result) {
            return @Result;
        }
    }

    # get user object
    my $UserObject = $Kernel::OM->Get('Kernel::System::User');

    my %User = $UserObject->GetUserData(
        UserID => $Param{UserID},
    );

    # run stats function
    @Result = $StatObject->Run(
        %GetParam,

        # these two lines are requirements of me, perhaps this
        # information is needed for former static stats
        Format => $Param{Format}->[0],
        Module => $Param{ObjectModule},
    );

    $Result[0]->[0] = $Param{Title} . ' ' . $Result[0]->[0];

    # write cache if configured
    if ( $Param{Cache} ) {
        $Self->_WriteResultCache(
            GetParam => \%GetParam,
            StatID   => $Param{StatID},
            Data     => \@Result,
        );
    }

    return @Result;
}

=head2 _GenerateDynamicStats()

    take the stat configuration and get the stat table

    my @StatArray = $StatsObject->_GenerateDynamicStats(
        ObjectModule     => 'Kernel::System::Stats::Dynamic::Ticket',
        Object           => 'Ticket',
        UseAsXvalue      => \UseAsXvalueElements,
        UseAsValueSeries => \UseAsValueSeriesElements,
        UseAsRestriction => \UseAsRestrictionElements,
        Title            => 'TicketStat',
        StatID           => 123,
        TimeZone         => 'Europe/Berlin',    # optional,
        Cache            => 1,                  # optional,
        Preview          => 1,                  # optional, generate fake data
        UserID           => $UserID,
    );

=cut

# search for a better way to cache stats (see lines before StatID and Cache)

sub _GenerateDynamicStats {
    my ( $Self, %Param ) = @_;

    my @HeaderLine;
    my $TitleTimeStart = '';
    my $TitleTimeStop  = '';

    my $Preview = $Param{Preview};
    my $UserID  = $Param{UserID};

    NEED:
    for my $Need (qw(ObjectModule UseAsXvalue UseAsValueSeries Title Object StatID UserID)) {
        next NEED if $Param{$Need};
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Need $Need!"
        );
        return;
    }

    # include the needed dynamic object
    my $ObjectModule = $Param{ObjectModule};
    return if !$Kernel::OM->Get('Kernel::System::Main')->Require($ObjectModule);
    my $StatObject = $ObjectModule->new( %{$Self} );
    return if !$StatObject;
    return if !$StatObject->can('GetStatTable') && !$StatObject->can('GetStatElement');

    # get time object
    # my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');

    # get the selected values
    # perhaps i can split the StatGet function to make this needless
    # Problem, i need the block information
    my %NewParam;

    $NewParam{Title}        = $Param{Title};
    $NewParam{Object}       = $Param{Object};
    $NewParam{ObjectModule} = $Param{ObjectModule};

    if ( $Param{TimeZone} ) {
        $NewParam{TimeZone} = $Param{TimeZone};
    }

    # search for a better way to cache stats (StatID and Cache)
    $NewParam{StatID} = $Param{StatID};
    $NewParam{Cache}  = $Param{Cache};
    for my $Use (qw(UseAsRestriction UseAsXvalue UseAsValueSeries)) {
        my @Array = @{ $Param{$Use} };
        ELEMENT:
        for my $Element (@Array) {
            next ELEMENT if !$Element->{Selected};

            # Clone the element as we are going to modify it - avoid modifying the original data
            $Element = ${ $Kernel::OM->Get('Kernel::System::Storable')->Clone( Data => \$Element ) };

            delete $Element->{Selected};
            delete $Element->{Fixed};
            if ( $Element->{Block} eq 'Time' ) {
                delete $Element->{TimePeriodFormat};
                if ( $Element->{TimeRelativeUnit} ) {

                    my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');

                    # add the selected timezone to the current timestamp
                    # to get the real start timestamp for the selected timezone
                    if ( $Param{TimeZone} ) {
                        $DateTimeObject->ToTimeZone(
                            TimeZone => $Param{TimeZone},
                        );
                    }

                    my $DateTimeValues = $DateTimeObject->Get();
                    my ( $s, $m, $h, $D, $M, $Y ) = (
                        $DateTimeValues->{Second},
                        $DateTimeValues->{Minute},
                        $DateTimeValues->{Hour},
                        $DateTimeValues->{Day},
                        $DateTimeValues->{Month},
                        $DateTimeValues->{Year},
                    );

                    # -1 because the current time will be included
                    my $CountUpcoming = $Element->{TimeRelativeUpcomingCount} - 1;

                    # add the upcoming count to the count past for the calculation
                    my $CountPast = $Element->{TimeRelativeCount} + $CountUpcoming;

                    if ( $Element->{TimeRelativeUnit} eq 'Year' ) {
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, $CountUpcoming, 0, 0 );
                        $Element->{TimeStop} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, 12, 31, 23, 59, 59 );
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, -$CountPast, 0, 0 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, 1, 1, 0, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'HalfYear' ) {

                        # $CountUpcoming was reduced by 1 before, this has to be reverted for half-year
                        $CountUpcoming++;

                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD(
                            $Y, $M, $D, 0, ( $M > 6 ? 1 : 0 ) * 6 - $M + ( 6 * $CountUpcoming ),
                            0
                        );
                        $Element->{TimeStop} = sprintf(
                            "%04d-%02d-%02d %02d:%02d:%02d",
                            $Y, $M, $Self->_DaysInMonth( $Y, $M ),
                            23, 59, 59
                        );

                        # $CountPast was reduced by 1 before, this has to be reverted for half-year
                        #     Examples:
                        #     Half-year set to 1, $CountPast will be 0 then - 0 * 6 = 0 (means this half-year)
                        #     Half-year set to 2, $CountPast will be 1 then - 1 * 6 = 6 (means last half-year)
                        #     With the fix, example 1 will mean last half-year and example 2 will mean
                        #     last two half-years
                        $CountPast++;
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, -$CountPast * 6 + 1, 0 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, 1, 0, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Quarter' ) {

                        # $CountUpcoming was reduced by 1 before, this has to be reverted for quarter
                        $CountUpcoming++;

                        my $LastQuarter = ceil( $M / 3 ) - 1;
                        ( $Y, $M, $D )
                            = $Self->_AddDeltaYMD( $Y, $M, $D, 0, $LastQuarter * 3 - $M + ( 3 * $CountUpcoming ), 0 );
                        $Element->{TimeStop} = sprintf(
                            "%04d-%02d-%02d %02d:%02d:%02d",
                            $Y, $M, $Self->_DaysInMonth( $Y, $M ),
                            23, 59, 59
                        );

                        # $CountPast was reduced by 1 before, this has to be reverted for quarter
                        #     Examples:
                        #     Quarter set to 1, $CountPast will be 0 then - 0 * 3 = 0 (means this quarter)
                        #     Quarter set to 2, $CountPast will be 1 then - 1 * 3 = 3 (means last quarter)
                        #     With the fix, example 1 will mean last quarter and example 2 will mean
                        #     last two quarters
                        $CountPast++;
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, -$CountPast * 3 + 1, 0 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, 1, 0, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Month' ) {
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, $CountUpcoming, 0 );
                        $Element->{TimeStop} = sprintf(
                            "%04d-%02d-%02d %02d:%02d:%02d",
                            $Y, $M, $Self->_DaysInMonth( $Y, $M ),
                            23, 59, 59
                        );
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, -$CountPast, 0 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, 1, 0, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Week' ) {

                        # $CountUpcoming was reduced by 1 before, this has to be reverted for week
                        $CountUpcoming++;

                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, 0, ( $CountUpcoming * 7 ) - 1 );
                        $Element->{TimeStop} = sprintf(
                            "%04d-%02d-%02d %02d:%02d:%02d",
                            $Y, $M, $D, 23, 59, 59
                        );

                        # $CountPast was reduced by 1 before, this has to be reverted for Week
                        #     Examples:
                        #     Week set to 1, $CountPast will be 0 then - 0 * 7 = 0 (means today)
                        #     Week set to 2, $CountPast will be 1 then - 1 * 7 = 7 (means last week)
                        #     With the fix, example 1 will mean last week and example 2 will mean
                        #     last two weeks
                        $CountPast++;
                        ( $Y, $M, $D ) = $Self->_AddDeltaDays( $Y, $M, $D, -$CountPast * 7 + 1 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, 0, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Day' ) {
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, 0, $CountUpcoming );
                        $Element->{TimeStop} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, 23, 59, 59 );
                        ( $Y, $M, $D ) = $Self->_AddDeltaYMD( $Y, $M, $D, 0, 0, -$CountPast );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, 0, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Hour' ) {
                        ( $Y, $M, $D, $h, $m, $s )
                            = $Self->_AddDeltaDHMS( $Y, $M, $D, $h, $m, $s, 0, $CountUpcoming, 0, 0 );
                        $Element->{TimeStop} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, $h, 59, 59 );
                        ( $Y, $M, $D, $h, $m, $s )
                            = $Self->_AddDeltaDHMS( $Y, $M, $D, $h, $m, $s, 0, -$CountPast, 0, 0 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, $h, 0, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Minute' ) {
                        ( $Y, $M, $D, $h, $m, $s )
                            = $Self->_AddDeltaDHMS( $Y, $M, $D, $h, $m, $s, 0, 0, $CountUpcoming, 0 );
                        $Element->{TimeStop} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, $h, $m, 59 );
                        ( $Y, $M, $D, $h, $m, $s )
                            = $Self->_AddDeltaDHMS( $Y, $M, $D, $h, $m, $s, 0, 0, -$CountPast, 0 );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, $h, $m, 0 );
                    }
                    elsif ( $Element->{TimeRelativeUnit} eq 'Second' ) {
                        ( $Y, $M, $D, $h, $m, $s )
                            = $Self->_AddDeltaDHMS( $Y, $M, $D, $h, $m, $s, 0, 0, 0, $CountUpcoming );
                        $Element->{TimeStop} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, $h, $m, $s );
                        ( $Y, $M, $D, $h, $m, $s )
                            = $Self->_AddDeltaDHMS( $Y, $M, $D, $h, $m, $s, 0, 0, 0, -$CountPast );
                        $Element->{TimeStart} = sprintf( "%04d-%02d-%02d %02d:%02d:%02d", $Y, $M, $D, $h, $m, $s );
                    }
                    delete $Element->{TimeRelativeUnit};
                    delete $Element->{TimeRelativeCount};
                    delete $Element->{TimeRelativeUpcomingCount};
                }

                $TitleTimeStart = $Element->{TimeStart};
                $TitleTimeStop  = $Element->{TimeStop};
            }

            # Select All function needed from otrs.GenerateStats.pl and fixed values of the frontend
            elsif ( !$Element->{SelectedValues}[0] ) {
                my @Values = keys( %{ $Element->{Values} } );
                $Element->{SelectedValues} = \@Values;
            }

            push @{ $NewParam{$Use} }, $Element;
        }
    }

    %Param = %NewParam;

    # get all restrictions for the search
    my %RestrictionAttribute;
    for my $RestrictionPart ( @{ $Param{UseAsRestriction} } ) {
        my $Element = $RestrictionPart->{Element};
        if ( $RestrictionPart->{Block} eq 'InputField' ) {
            $RestrictionAttribute{$Element} = $RestrictionPart->{SelectedValues}[0];
        }
        elsif ( $RestrictionPart->{Block} eq 'SelectField' ) {
            $RestrictionAttribute{$Element} = $RestrictionPart->{SelectedValues}[0];
        }
        elsif ( $RestrictionPart->{Block} eq 'Time' ) {

            # convert start and stop time to OTRS time zone
            $RestrictionAttribute{ $RestrictionPart->{Values}{TimeStart} } = $Self->_ToOTRSTimeZone(
                String   => $RestrictionPart->{TimeStart},
                TimeZone => $Param{TimeZone},
            );

            $RestrictionAttribute{ $RestrictionPart->{Values}{TimeStop} } = $Self->_ToOTRSTimeZone(
                String   => $RestrictionPart->{TimeStop},
                TimeZone => $Param{TimeZone},
            );
        }
        else {
            $RestrictionAttribute{$Element} = $RestrictionPart->{SelectedValues};
        }
    }

    # get needed objects
    my $LanguageObject = $Kernel::OM->Get('Kernel::Language');
    my $UserObject     = $Kernel::OM->Get('Kernel::System::User');

    my %User = $UserObject->GetUserData(
        UserID => $UserID,
    );

    # get the selected Xvalue
    my $Xvalue = {};
    my (
        $VSYear,     $VSMonth,     $VSDay,     $VSHour,     $VSMinute,     $VSSecond,
        $VSStopYear, $VSStopMonth, $VSStopDay, $VSStopHour, $VSStopMinute, $VSStopSecond
    );
    my $TimeAbsolutStopUnixTime = 0;
    my $Count                   = 0;
    my $MonthArrayRef           = _MonthArray();

    my $Element = $Param{UseAsXvalue}[0];
    if ( $Element->{Block} eq 'Time' ) {
        my (
            $Year,   $Month,   $Day,   $Hour,   $Minute,   $Second,
            $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond
        );
        if ( $Element->{TimeStart} =~ m{^(\d\d\d\d)-(\d\d)-(\d\d)\s(\d\d):(\d\d):(\d\d)$}ix ) {
            $Year   = $VSYear   = $1;
            $Month  = $VSMonth  = int $2;
            $Day    = $VSDay    = int $3;
            $Hour   = $VSHour   = int $4;
            $Minute = $VSMinute = int $5;
            $Second = $VSSecond = int $6;
        }

        my $DateTimeObject = $Kernel::OM->Create(
            'Kernel::System::DateTime',
            ObjectParams => {
                String => $Element->{TimeStop},
            }
        );
        $TimeAbsolutStopUnixTime = $DateTimeObject->ToEpoch();

        my $TimeStart = 0;
        my $TimeStop  = 0;

        $Count = $Element->{TimeScaleCount} ? $Element->{TimeScaleCount} : 1;

        # in these constellation $Count > 1 is not useful!!
        if (
            $Param{UseAsValueSeries}
            && $Param{UseAsValueSeries}[0]{Block}
            && $Param{UseAsValueSeries}[0]{Block} eq 'Time'
            && $Element->{SelectedValues}[0] eq 'Day'
            )
        {
            $Count = 1;
        }

        if ( $Element->{SelectedValues}[0] eq 'Minute' ) {
            $Second = 0;
        }
        elsif ( $Element->{SelectedValues}[0] eq 'Hour' ) {
            $Second = 0;
            $Minute = 0;
        }
        elsif ( $Element->{SelectedValues}[0] eq 'Day' ) {
            $Second = 0;
            $Minute = 0;
            $Hour   = 0;
        }
        elsif ( $Element->{SelectedValues}[0] eq 'Week' ) {
            $Second = 0;
            $Minute = 0;
            $Hour   = 0;
            ( $Year, $Month, $Day ) = $Self->_MondayOfWeek( $Year, $Month, $Day );
        }
        elsif ( $Element->{SelectedValues}[0] eq 'Month' ) {
            $Second = 0;
            $Minute = 0;
            $Hour   = 0;
            $Day    = 1;
        }
        elsif ( $Element->{SelectedValues}[0] eq 'Quarter' ) {
            $Second = 0;
            $Minute = 0;
            $Hour   = 0;
            $Day    = 1;

            # calculate the start month for the quarter
            my $QuarterNum = ceil( $Month / 3 );
            $Month = ( $QuarterNum * 3 ) - 2;
        }
        elsif ( $Element->{SelectedValues}[0] eq 'HalfYear' ) {
            $Second = 0;
            $Minute = 0;
            $Hour   = 0;
            $Day    = 1;

            # calculate the start month for the half-year
            my $HalfYearNum = ceil( $Month / 6 );
            $Month = ( $HalfYearNum * 6 ) - 5;
        }
        elsif ( $Element->{SelectedValues}[0] eq 'Year' ) {
            $Second = 0;
            $Minute = 0;
            $Hour   = 0;
            $Day    = 1;
            $Month  = 1;
        }

        # FIXME Timeheader zusammenbauen
        # my $DateTimeObject = $Kernel::OM->Create('Kernel::System::Datetime');
        while (
            !$TimeStop
            || (
                $DateTimeObject->Set( String => $TimeStop )
                && $DateTimeObject->ToEpoch()
                < $TimeAbsolutStopUnixTime
            )
            )
        {
            $TimeStart = sprintf(
                "%04d-%02d-%02d %02d:%02d:%02d",
                $Year, $Month, $Day, $Hour, $Minute, $Second
            );
            if ( $Element->{SelectedValues}[0] eq 'Second' ) {
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $Year, $Month, $Day, $Hour, $Minute, $Second, 0, 0, 0,
                    $Count - 1
                );
                push(
                    @HeaderLine,
                    sprintf(
                        "%02d:%02d:%02d-%02d:%02d:%02d",
                        $Hour, $Minute, $Second, $ToHour, $ToMinute, $ToSecond
                    )
                );
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Minute' ) {
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $Year, $Month, $Day, $Hour, $Minute, $Second, 0, 0, $Count,
                    -1
                );
                push(
                    @HeaderLine,
                    sprintf(
                        "%02d:%02d:%02d-%02d:%02d:%02d",
                        $Hour, $Minute, $Second, $ToHour, $ToMinute, $ToSecond
                    )
                );
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Hour' ) {
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $Year, $Month, $Day, $Hour, $Minute, $Second, 0, $Count, 0,
                    -1
                );
                push(
                    @HeaderLine,
                    sprintf(
                        "%02d:%02d:%02d-%02d:%02d:%02d",
                        $Hour, $Minute, $Second, $ToHour, $ToMinute, $ToSecond
                    )
                );
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Day' ) {
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $Year, $Month, $Day, $Hour, $Minute, $Second, $Count, 0, 0,
                    -1
                );
                my $Dow = $Self->_DayOfWeek( $Year, $Month, $Day );
                $Dow = $LanguageObject->Translate( $Self->_DayOfWeekAbbreviation($Dow) );
                if ( $ToDay eq $Day ) {
                    push @HeaderLine, "$Dow $Day";
                }
                else {
                    push(
                        @HeaderLine,
                        sprintf(
                            "%02d.%02d.%04d - %02d.%02d.%04d",
                            $Day, $Month, $Year, $ToDay, $ToMonth, $ToYear
                        )
                    );
                }
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Week' ) {
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $Year, $Month, $Day, 0, 0, $Count * 7 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $Hour, $Minute, $Second, 0, 0, 0,
                    -1
                );
                my %WeekNum;
                ( $WeekNum{Week}, $WeekNum{Year} ) = $Self->_WeekOfYear( $Year, $Month, $Day );
                my $TranslateWeek = $LanguageObject->Translate('week');
                push(
                    @HeaderLine,
                    sprintf( "$TranslateWeek %02d-%04d - ", $WeekNum{Week}, $WeekNum{Year} ) .
                        sprintf(
                        "%02d.%02d.%04d - %02d.%02d.%04d",
                        $Day, $Month, $Year, $ToDay, $ToMonth, $ToYear
                        )
                );
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Month' ) {
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $Year, $Month, $Day, 0, $Count, 0 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $Hour, $Minute, $Second, 0, 0, 0,
                    -1
                );
                if ( $ToMonth eq $Month ) {
                    my $TranslateMonth = $LanguageObject->Translate( $MonthArrayRef->[$Month] );
                    push @HeaderLine, "$TranslateMonth $Month";
                }
                else {
                    push(
                        @HeaderLine,
                        sprintf(
                            "%02d.%02d.%04d - %02d.%02d.%04d",
                            $Day, $Month, $Year, $ToDay, $ToMonth, $ToYear
                        )
                    );
                }
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Quarter' ) {
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $Year, $Month, $Day, 0, $Count * 3, 0 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $Hour, $Minute, $Second, 0, 0, 0,
                    -1
                );

                if ( ( $ToMonth - $Month ) == 2 ) {
                    my $QuarterNum       = ceil( $Month / 3 );
                    my $TranslateQuarter = $LanguageObject->Translate('quarter');
                    push(
                        @HeaderLine,
                        sprintf( "$TranslateQuarter $QuarterNum-%04d", $Year )
                    );
                }
                else {
                    push(
                        @HeaderLine,
                        sprintf(
                            "%02d.%02d.%04d - %02d.%02d.%04d",
                            $Day, $Month, $Year, $ToDay, $ToMonth, $ToYear
                        )
                    );
                }
            }
            elsif ( $Element->{SelectedValues}[0] eq 'HalfYear' ) {
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $Year, $Month, $Day, 0, $Count * 6, 0 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $Hour, $Minute, $Second, 0, 0, 0,
                    -1
                );

                if ( ( $ToMonth - $Month ) == 5 ) {
                    my $HalfYearNum       = ceil( $Month / 6 );
                    my $TranslateHalfYear = $LanguageObject->Translate('half-year');
                    push(
                        @HeaderLine,
                        sprintf( "$TranslateHalfYear $HalfYearNum-%04d", $Year )
                    );
                }
                else {
                    push(
                        @HeaderLine,
                        sprintf(
                            "%02d.%02d.%04d - %02d.%02d.%04d",
                            $Day, $Month, $Year, $ToDay, $ToMonth, $ToYear
                        )
                    );
                }
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Year' ) {
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $Year, $Month, $Day, $Count, 0, 0 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $Hour, $Minute, $Second, 0, 0, 0,
                    -1
                );
                if ( $ToYear eq $Year ) {
                    push @HeaderLine, $Year;
                }
                else {
                    push(
                        @HeaderLine,
                        sprintf(
                            "%02d.%02d.%04d - %02d.%02d.%04d",
                            $Day, $Month, $Year, $ToDay, $ToMonth, $ToYear
                        )
                    );
                }
            }
            ( $Year, $Month, $Day, $Hour, $Minute, $Second ) = $Self->_AddDeltaDHMS(
                $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0, 0, 0,
                1
            );
            $TimeStop = sprintf(
                "%04d-%02d-%02d %02d:%02d:%02d",
                $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond
            );

            push(
                @{ $Xvalue->{SelectedValues} },
                {
                    # convert to OTRS time zone for correct database search parameter

                    TimeStart => $Self->_ToOTRSTimeZone(
                        String   => $TimeStart,
                        TimeZone => $Param{TimeZone},
                    ),

                    TimeStop => $Self->_ToOTRSTimeZone(
                        String   => $TimeStop,
                        TimeZone => $Param{TimeZone},
                    ),
                }
            );
        }

        $Xvalue->{Block}  = 'Time';
        $Xvalue->{Values} = $Element->{Values};
    }

    # if Block equal MultiSelectField, Selectfield
    else {
        $Xvalue = $Element;

        # build the headerline

        for my $Valuename ( @{ $Xvalue->{SelectedValues} } ) {

            # Do not translate the values, please see bug#12384 for more information.
            push @HeaderLine, $Xvalue->{Values}{$Valuename};
        }

        # Prevent randomization of x-axis in preview, sort it alphabetically see bug#12714.
        if ($Preview) {
            @HeaderLine = sort { lc($a) cmp lc($b) } @HeaderLine;
        }
    }

    # get the value series
    my %ValueSeries;
    my @ArraySelected;
    my $ColumnName = '';
    my $HeaderLineStart;

    # give me all possible elements for Value Series
    REF1:
    for my $Ref1 ( @{ $Param{UseAsValueSeries} } ) {

        # all elements which are shown with multiselectfields
        if ( $Ref1->{Block} ne 'Time' ) {
            my %SelectedValues;
            for my $Ref2 ( @{ $Ref1->{SelectedValues} } ) {

                # Do not translate the values, please see bug#12384 for more information.
                $SelectedValues{$Ref2} = $Ref1->{Values}{$Ref2};
            }
            push(
                @ArraySelected,
                {
                    Values  => \%SelectedValues,
                    Element => $Ref1->{Element},
                    Name    => $Ref1->{Name},
                    Block   => $Ref1->{Block},
                }
            );
            next REF1;
        }

        # timescale elements need a special handling, so we save the start value and reset the HeaderLine
        $HeaderLineStart = $HeaderLine[0];
        @HeaderLine      = ();

        # these all makes only sense, if the count of xaxis is 1
        if ( $Ref1->{SelectedValues}[0] eq 'Year' ) {

            if ( $Element->{SelectedValues}[0] eq 'Month' ) {

                if ( $Count == 1 ) {
                    for my $Month ( 1 .. 12 ) {
                        push @HeaderLine, "$MonthArrayRef->[$Month] $Month";
                    }
                }
                else {
                    for ( my $Month = 1; $Month < 12; $Month += $Count ) {
                        push(
                            @HeaderLine,
                            "$MonthArrayRef->[$Month] - $MonthArrayRef->[$Month + $Count - 1]"
                        );
                    }
                }
                $VSSecond = 0;
                $VSMinute = 0;
                $VSHour   = 0;
                $VSDay    = 1;
                $VSMonth  = 1;
            }
            elsif ( $Element->{SelectedValues}[0] eq 'Quarter' ) {

                my $TranslateQuarter = $LanguageObject->Translate('quarter');
                for my $Quarter ( 1 .. 4 ) {
                    push @HeaderLine, "$TranslateQuarter $Quarter";
                }
                $VSSecond = 0;
                $VSMinute = 0;
                $VSHour   = 0;
                $VSDay    = 1;
                $VSMonth  = 1;

                # remove the year from the HeaderLineStart value to have the same values as the new generated HeaderLine
                $HeaderLineStart =~ s{ -\d\d\d\d }{}xms;
            }
            elsif ( $Element->{SelectedValues}[0] eq 'HalfYear' ) {

                my $TranslateHalfYear = $LanguageObject->Translate('half-year');
                for my $HalfYear ( 1 .. 2 ) {
                    push @HeaderLine, "$TranslateHalfYear $HalfYear";
                }
                $VSSecond = 0;
                $VSMinute = 0;
                $VSHour   = 0;
                $VSDay    = 1;
                $VSMonth  = 1;

                # remove the year from the HeaderLineStart value to have the same values as the new generated HeaderLine
                $HeaderLineStart =~ s{ -\d\d\d\d }{}xms;
            }

            $ColumnName = 'Year';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Month' ) {

            for my $Count ( 1 .. 31 ) {
                push @HeaderLine, $Count;
            }

            $VSSecond   = 0;
            $VSMinute   = 0;
            $VSHour     = 0;
            $VSDay      = 1;
            $ColumnName = 'Month';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Week' ) {

            for my $Count ( 1 .. 7 ) {
                push @HeaderLine, $Self->_DayOfWeekToText($Count);
            }

            $VSSecond   = 0;
            $VSMinute   = 0;
            $VSHour     = 0;
            $ColumnName = 'Week';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Day' ) {
            for ( my $Hour = 0; $Hour < 24; $Hour += $Count ) {
                push @HeaderLine, sprintf( "%02d:00:00-%02d:59:59", $Hour, $Hour + $Count - 1 );
            }
            $VSSecond   = 0;
            $VSMinute   = 0;
            $VSHour     = 0;
            $ColumnName = 'Day';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Hour' ) {
            for ( my $Minute = 0; $Minute < 60; $Minute += $Count ) {
                my $Time = 'min ' . $Minute . ' - ' . ( $Minute + $Count );
                push @HeaderLine, $Time;
            }
            $VSSecond   = 0;
            $VSMinute   = 0;
            $ColumnName = 'Hour';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Minute' ) {
            if ( $Count == 1 ) {
                for my $Index ( 0 .. 59 ) {
                    my $Time = 'sec ' . $Index;
                    push @HeaderLine, $Time;
                }
            }
            else {
                for ( my $Second = 0; $Second < 60; $Second += $Count ) {
                    my $Time = 'sec ' . $Second . '-' . ( $Second + $Count );
                    push @HeaderLine, $Time;
                }
            }
            $VSSecond   = 0;
            $ColumnName = 'Minute';
        }

        my $TimeStart     = 0;
        my $TimeStop      = 0;
        my $MonthArrayRef = _MonthArray();

        $Count = 1;

        # Generate the time value series
        my ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond );

        my $DateTimeObject = $Kernel::OM->Create('Kernel::System::DateTime');
        if ( $Ref1->{SelectedValues}[0] eq 'Year' ) {
            while (
                !$TimeStop || (
                    $DateTimeObject->Set( String => $TimeStop )
                    && $DateTimeObject->ToEpoch()
                    < $TimeAbsolutStopUnixTime
                )
                )
            {
                $TimeStart = sprintf( "%04d-01-01 00:00:00", $VSYear );
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $VSYear, $VSMonth, $VSDay, $Count, 0, 0 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $VSHour, $VSMinute, $VSSecond, 0,
                    0, 0, -1
                );
                $TimeStop = sprintf( "%04d-12-31 23:59:59", $ToYear );

                $ValueSeries{$VSYear} = {
                    $Ref1->{Values}{TimeStop}  => $TimeStop,
                    $Ref1->{Values}{TimeStart} => $TimeStart
                };

                ( $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0,
                    0, 0, 1
                );
            }
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Month' ) {
            while (
                !$TimeStop || (
                    $DateTimeObject->Set( String => $TimeStop )
                    && $DateTimeObject->ToEpoch()
                    < $TimeAbsolutStopUnixTime
                )
                )
            {
                $TimeStart = sprintf( "%04d-%02d-01 00:00:00", $VSYear, $VSMonth );
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaYMD( $VSYear, $VSMonth, $VSDay, 0, $Count, 0 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $VSHour, $VSMinute, $VSSecond, 0,
                    0, 0, -1
                );
                $TimeStop = sprintf( "%04d-%02d-%02d 23:59:59", $ToYear, $ToMonth, $ToDay );

                my $TranslateMonth = $LanguageObject->Translate( $MonthArrayRef->[$VSMonth] );

                $ValueSeries{
                    $VSYear . '-'
                        . sprintf( "%02d", $VSMonth ) . ' '
                        . $TranslateMonth
                    } = {
                    $Ref1->{Values}{TimeStop}  => $TimeStop,
                    $Ref1->{Values}{TimeStart} => $TimeStart
                    };

                ( $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0,
                    0, 0, 1
                );
            }

            # remove the value for this selected value
            $HeaderLineStart = '';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Week' ) {
            while (
                !$TimeStop || (
                    $DateTimeObject->Set( String => $TimeStop )
                    && $DateTimeObject->ToEpoch()
                    < $TimeAbsolutStopUnixTime
                )
                )
            {
                my @Monday = $Self->_MondayOfWeek( $VSYear, $VSMonth, $VSDay );

                $TimeStart = sprintf( "%04d-%02d-%02d 00:00:00", @Monday );
                ( $ToYear, $ToMonth, $ToDay ) = $Self->_AddDeltaDays( @Monday, $Count * 7 );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $VSHour, $VSMinute, $VSSecond, 0,
                    0, 0, -1
                );
                $TimeStop = sprintf( "%04d-%02d-%02d 23:59:59", $ToYear, $ToMonth, $ToDay );

                $ValueSeries{
                    sprintf( "%04d-%02d-%02d", @Monday ) . ' - '
                        . sprintf( "%04d-%02d-%02d", $ToYear, $ToMonth, $ToDay )
                    } = {
                    $Ref1->{Values}{TimeStop}  => $TimeStop,
                    $Ref1->{Values}{TimeStart} => $TimeStart
                    };

                ( $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0,
                    0, 0, 1
                );
            }

            # remove the value for this selected value
            $HeaderLineStart = '';
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Day' ) {
            while (
                !$TimeStop || (
                    $DateTimeObject->Set( String => $TimeStop )
                    && $DateTimeObject->ToEpoch()
                    < $TimeAbsolutStopUnixTime
                )
                )
            {
                $TimeStart = sprintf( "%04d-%02d-%02d 00:00:00", $VSYear, $VSMonth, $VSDay );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond,
                    $Count,  0,        0,      -1
                );
                $TimeStop = sprintf( "%04d-%02d-%02d 23:59:59", $ToYear, $ToMonth, $ToDay );

                $ValueSeries{ sprintf( "%04d-%02d-%02d", $VSYear, $VSMonth, $VSDay ) } = {
                    $Ref1->{Values}{TimeStop}  => $TimeStop,
                    $Ref1->{Values}{TimeStart} => $TimeStart
                };

                ( $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0,
                    0, 0, 1
                );
            }
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Hour' ) {
            while (
                !$TimeStop || (
                    $DateTimeObject->Set( String => $TimeStop )
                    && $DateTimeObject->ToEpoch()
                    < $TimeAbsolutStopUnixTime
                )
                )
            {
                $TimeStart = sprintf( "%04d-%02d-%02d %02d:00:00", $VSYear, $VSMonth, $VSDay, $VSHour );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond, 0,
                    $Count,  0,        -1
                );
                $TimeStop = sprintf( "%04d-%02d-%02d %02d:59:59", $ToYear, $ToMonth, $ToDay, $ToHour );
                $ValueSeries{
                    sprintf(
                        "%04d-%02d-%02d %02d:00:00 - %02d:59:59",
                        $VSYear, $VSMonth, $VSDay, $VSHour, $ToHour
                    )
                    } = {
                    $Ref1->{Values}{TimeStop}  => $TimeStop,
                    $Ref1->{Values}{TimeStart} => $TimeStart
                    };
                ( $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0,
                    0, 0, 1
                );
            }
        }
        elsif ( $Ref1->{SelectedValues}[0] eq 'Minute' ) {
            while (
                !$TimeStop || (
                    $DateTimeObject->Set( String => $TimeStop )
                    && $DateTimeObject->ToEpoch()
                    < $TimeAbsolutStopUnixTime
                )
                )
            {
                $TimeStart = sprintf(
                    "%04d-%02d-%02d %02d:%02d:00",
                    $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute
                );
                ( $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond ) = $Self->_AddDeltaDHMS(
                    $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond, 0,
                    0,       $Count,   -1
                );
                $TimeStop = sprintf(
                    "%04d-%02d-%02d %02d:%02d:59",
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute
                );
                $ValueSeries{
                    sprintf(
                        "%04d-%02d-%02d %02d:%02d:00 - %02d:%02d:59",
                        $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $ToHour, $ToMinute
                    )
                    } = {
                    $Ref1->{Values}{TimeStop}  => $TimeStop,
                    $Ref1->{Values}{TimeStart} => $TimeStart
                    };
                ( $VSYear, $VSMonth, $VSDay, $VSHour, $VSMinute, $VSSecond ) = $Self->_AddDeltaDHMS(
                    $ToYear, $ToMonth, $ToDay, $ToHour, $ToMinute, $ToSecond, 0,
                    0, 0, 1
                );
            }
        }
    }

    # merge the array if two elements for the valueseries are avialable
    if ( $ArraySelected[0] ) {
        KEY:
        for my $Key ( sort keys %{ $ArraySelected[0]{Values} } ) {
            my $Value0;
            if ( $ArraySelected[0]{Block} eq 'SelectField' ) {
                $Value0 = $Key;
            }
            elsif ( $ArraySelected[0]{Block} eq 'MultiSelectField' ) {
                $Value0 = [$Key];
            }

            if ( !$ArraySelected[1] ) {
                $ValueSeries{ $ArraySelected[0]{Values}{$Key} } = { $ArraySelected[0]{Element} => $Value0 };
                next KEY;
            }

            for my $SubKey ( sort keys %{ $ArraySelected[1]{Values} } ) {
                my $Value1;
                if ( $ArraySelected[1]{Block} eq 'SelectField' ) {
                    $Value1 = $SubKey;
                }
                elsif ( $ArraySelected[1]{Block} eq 'MultiSelectField' ) {
                    $Value1 = [$SubKey];
                }
                $ValueSeries{
                    $ArraySelected[0]{Values}{$Key} . ' - '
                        . $ArraySelected[1]{Values}{$SubKey}
                    } = {
                    $ArraySelected[0]{Element} => $Value0,
                    $ArraySelected[1]{Element} => $Value1
                    };
            }
        }
    }

    # Use this if no valueseries available
    if ( !%ValueSeries ) {
        $ValueSeries{ $Param{Object} . 's' } = undef;
    }

    # get the first column name in the headerline
    if ($ColumnName) {
        unshift @HeaderLine, $LanguageObject->Translate($ColumnName);
    }
    elsif ( $ArraySelected[1] ) {
        unshift(
            @HeaderLine,
            $LanguageObject->Translate( $ArraySelected[0]{Name} ) . ' - '
                . $LanguageObject->Translate( $ArraySelected[1]{Name} )
        );
    }
    elsif ( $ArraySelected[0] ) {
        unshift( @HeaderLine, $LanguageObject->Translate( $ArraySelected[0]{Name} ) || '' );
    }
    else {

        # in cases where there is no value set, then the headers get wrong unless a empty element
        #    is added in the header, bug 9796
        #
        #   e.g. from:
        #    Raw    | Misc | PostMaster |    |
        #    Ticket | 10   | 20         | 30 |
        #
        #    to:
        #           | Raw | Misc | PostMaster |
        #    Ticket | 10  | 20   | 30         |
        unshift( @HeaderLine, '' );
    }

    # push the first array elements in the StatsArray
    my $Title = $Param{Title};
    if ( $TitleTimeStart && $TitleTimeStop ) {
        $Title .= " $TitleTimeStart-$TitleTimeStop";
    }

    # Extend the title, e.g. to add a fixed time period from the stats object.
    if ( $StatObject->can('GetExtendedTitle') ) {
        my $ExtendedTitle = $StatObject->GetExtendedTitle(
            XValue       => $Xvalue,
            Restrictions => \%RestrictionAttribute,
        );
        if ($ExtendedTitle) {
            $Title .= ' ' . $ExtendedTitle;
        }
    }

    # create the cache string
    my $CacheString = $Self->_GetCacheString(%Param);

    # take the cache value if configured and available
    if ( $Param{Cache} && !$Preview ) {
        my @StatArray = $Self->_GetResultCache(
            Filename => 'Stats' . $Param{StatID} . '-' . $CacheString . '.cache',
        );

        if (@StatArray) {
            return @StatArray;
        }
    }

    # create the table structure
    my %TableStructure;
    for my $Row ( sort keys %ValueSeries ) {
        my @Cells;
        CELL:
        for my $Cell ( @{ $Xvalue->{SelectedValues} } ) {    # get each cell
            $ValueSeries{$Row} ||= {};
            my %Attributes = ( %{ $ValueSeries{$Row} }, %RestrictionAttribute );

            # the following is necessary if as x-axis and as value-series time is selected
            if ( $Xvalue->{Block} eq 'Time' ) {
                my $TimeStart = $Xvalue->{Values}{TimeStart};
                my $TimeStop  = $Xvalue->{Values}{TimeStop};
                if ( $ValueSeries{$Row}{$TimeStop} && $ValueSeries{$Row}{$TimeStart} ) {

                    my $CellStartTime = $Self->_TimeStamp2DateTime( TimeStamp => $Cell->{TimeStart} );
                    my $CellStopTime  = $Self->_TimeStamp2DateTime( TimeStamp => $Cell->{TimeStop} );
                    my $ValueSeriesStartTime
                        = $Self->_TimeStamp2DateTime( TimeStamp => $ValueSeries{$Row}{$TimeStart} );
                    my $ValueSeriesStopTime = $Self->_TimeStamp2DateTime( TimeStamp => $ValueSeries{$Row}{$TimeStop} );

                    if ( $CellStopTime > $ValueSeriesStopTime || $CellStartTime < $ValueSeriesStartTime ) {
                        next CELL;
                    }

                }
                $Attributes{$TimeStop}  = $Cell->{TimeStop};
                $Attributes{$TimeStart} = $Cell->{TimeStart};
            }
            elsif ( $Xvalue->{Block} eq 'SelectField' ) {
                $Attributes{ $Xvalue->{Element} } = $Cell;
            }
            else {
                $Attributes{ $Xvalue->{Element} } = [$Cell];
            }
            push @Cells, \%Attributes;
        }
        $TableStructure{$Row} = \@Cells;
    }

    my @DataArray;

    # Dynamic List Statistic
    if ( $StatObject->can('GetStatTable') ) {

        if ($Preview) {
            return if !$StatObject->can('GetStatTablePreview');

            @DataArray = $StatObject->GetStatTablePreview(
                ValueSeries    => $Param{UseAsValueSeries},    #\%ValueSeries,
                XValue         => $Xvalue,
                Restrictions   => \%RestrictionAttribute,
                TableStructure => \%TableStructure,
                TimeZone       => $Param{TimeZone},
            );
        }
        else {
            # get the whole stats table
            @DataArray = $StatObject->GetStatTable(
                ValueSeries    => $Param{UseAsValueSeries},    #\%ValueSeries,
                XValue         => $Xvalue,
                Restrictions   => \%RestrictionAttribute,
                TableStructure => \%TableStructure,
                TimeZone       => $Param{TimeZone},
            );
        }
    }

    # Dynamic Matrix Statistic
    else {

        if ($Preview) {
            return if !$StatObject->can('GetStatElementPreview');
        }

        for my $Row ( sort keys %TableStructure ) {
            my @ResultRow = ($Row);
            for my $Cell ( @{ $TableStructure{$Row} } ) {
                if ($Preview) {
                    push @ResultRow, $StatObject->GetStatElementPreview( %{$Cell} );
                }
                else {
                    push @ResultRow, $StatObject->GetStatElement( %{$Cell} ) || 0;
                }
            }
            push @DataArray, \@ResultRow;
        }

        my $RowCounter = 0;

        # fill up empty array elements, e.g month as value series (February has 28 day and Januar 31)
        for my $Row (@DataArray) {

            $RowCounter++;

            if ( $RowCounter == 1 && $HeaderLineStart ) {

                # determine the skipping counter
                my $SkippingCounter = 0;

                INDEX:
                for my $Index ( 1 .. $#HeaderLine ) {

                    if ( $HeaderLine[$Index] eq $HeaderLineStart ) {
                        last INDEX;
                    }

                    $SkippingCounter++;
                }

                for my $Index ( 1 .. $SkippingCounter ) {
                    splice @{$Row}, $Index, 0, '';
                }
            }

            for my $Index ( 1 .. $#HeaderLine ) {
                if ( !defined $Row->[$Index] ) {
                    $Row->[$Index] = '';
                }
            }
        }
    }

    # REMARK: it could be also useful to use the indiviual sort if difined
    # so you don't need this function
    if ( $StatObject->can('GetHeaderLine') ) {
        my $HeaderRef = $StatObject->GetHeaderLine(
            XValue       => $Xvalue,
            Restrictions => \%RestrictionAttribute,
        );

        if ($HeaderRef) {
            @HeaderLine = @{$HeaderRef};
        }
    }

    my @StatArray = ( [$Title], \@HeaderLine, @DataArray );

    if ( !$Param{Cache} || $Preview ) {
        return @StatArray;
    }

    # check if we should cache this result
    if ( !$TitleTimeStart || !$TitleTimeStop ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'notice',
            Message  => "Can't cache: StatID $Param{StatID} has no time period, so you can't cache the stat!",
        );
        return @StatArray;
    }

    # convert to OTRS time zone to get the correct time for the check
    my $CheckTimeStop = $Self->_ToOTRSTimeZone(
        String   => $TitleTimeStop,
        TimeZone => $Param{TimeZone},
    );

    my $DateTimeObject      = $Kernel::OM->Create('Kernel::System::DateTime');
    my $CheckTimeStopObject = $Self->_TimeStamp2DateTime(
        TimeStamp => $CheckTimeStop,
    );

    if ( $CheckTimeStopObject > $DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'notice',
            Message  => "Can't cache StatID $Param{StatID}: The selected end time is in the future!",
        );
        return @StatArray;
    }

    # write the stats cache
    $Self->_SetResultCache(
        Filename => 'Stats' . $Param{StatID} . '-' . $CacheString . '.cache',
        Result   => \@StatArray,
    );
    return @StatArray;
}

=head2 _ColumnAndRowTranslation()

Translate the column and row name if needed.

    $StatsObject->_ColumnAndRowTranslation(
        StatArrayRef => $StatArrayRef,
        StatRef      => $StatRef,
        ExchangeAxis => 1 | 0,
    );

=cut

sub _ColumnAndRowTranslation {
    my ( $Self, %Param ) = @_;

    # check if need params are available
    for my $NeededParam (qw(StatArrayRef StatRef)) {
        if ( !$Param{$NeededParam} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => "error",
                Message  => "_ColumnAndRowTranslation: Need $NeededParam!"
            );
        }
    }

    # Cut the statistic array in the three pieces, to handle the diffrent values for the translation.
    my $TitleArrayRef = shift @{ $Param{StatArrayRef} };
    my $HeadArrayRef  = shift @{ $Param{StatArrayRef} };
    my $StatArrayRef  = $Param{StatArrayRef};

    my $LanguageObject = $Kernel::OM->Get('Kernel::Language');

    # Find out, if the column or row names should be translated.
    my %Translation;
    my %Sort;

    for my $Use (qw( UseAsXvalue UseAsValueSeries )) {
        if (
            $Param{StatRef}->{StatType} eq 'dynamic'
            && $Param{StatRef}->{$Use}
            && ref( $Param{StatRef}->{$Use} ) eq 'ARRAY'
            )
        {

            my @Array = @{ $Param{StatRef}->{$Use} };

            ELEMENT:
            for my $Element (@Array) {
                next ELEMENT if !$Element->{Selected};

                if ( $Element->{Translation} && $Element->{Block} eq 'Time' ) {
                    $Translation{$Use} = 'Time';
                }
                elsif ( $Element->{Translation} ) {
                    $Translation{$Use} = 'Common';
                }
                else {
                    $Translation{$Use} = '';
                }

                if ( $Element->{Translation} && $Element->{Block} ne 'Time' && !$Element->{SortIndividual} ) {
                    $Sort{$Use} = 1;
                }

                last ELEMENT;
            }
        }
    }

    # Check if the axis are changed.
    if ( $Param{ExchangeAxis} ) {
        my $UseAsXvalueOld = $Translation{UseAsXvalue};
        $Translation{UseAsXvalue}      = $Translation{UseAsValueSeries};
        $Translation{UseAsValueSeries} = $UseAsXvalueOld;

        my $SortUseAsXvalueOld = $Sort{UseAsXvalue};
        $Sort{UseAsXvalue}      = $Sort{UseAsValueSeries};
        $Sort{UseAsValueSeries} = $SortUseAsXvalueOld;
    }

    # Translate the headline array, if all values must be translated and
    #   otherwise translate only the first value of the header.
    if ( $Translation{UseAsXvalue} && $Translation{UseAsXvalue} ne 'Time' ) {
        for my $Word ( @{$HeadArrayRef} ) {
            $Word = $LanguageObject->Translate($Word);
        }
    }
    else {
        $HeadArrayRef->[0] = $LanguageObject->Translate( $HeadArrayRef->[0] );
    }

    # Sort the headline array after translation.
    if ( $Sort{UseAsXvalue} ) {
        my @HeadOld = @{$HeadArrayRef};

        # Because the first value is no sortable column name
        shift @HeadOld;

        # Special handling if the sumfunction is used.
        my $SumColRef;
        if ( $Param{StatRef}->{SumCol} ) {
            $SumColRef = pop @HeadOld;
        }

        my @SortedHead = sort { $a cmp $b } @HeadOld;

        # Special handling if the sumfunction is used.
        if ( $Param{StatRef}->{SumCol} ) {
            push @SortedHead, $SumColRef;
            push @HeadOld,    $SumColRef;
        }

        # Add the row names to the new StatArray.
        my @StatArrayNew;
        for my $Row ( @{$StatArrayRef} ) {
            push @StatArrayNew, [ $Row->[0] ];
        }

        for my $ColumnName (@SortedHead) {
            my $Counter = 0;
            COLUMNNAMEOLD:
            for my $ColumnNameOld (@HeadOld) {
                $Counter++;
                next COLUMNNAMEOLD if $ColumnNameOld ne $ColumnName;

                for my $RowLine ( 0 .. $#StatArrayNew ) {
                    push @{ $StatArrayNew[$RowLine] }, $StatArrayRef->[$RowLine]->[$Counter];
                }
                last COLUMNNAMEOLD;
            }
        }

        # Bring the data back to the diffrent references.
        unshift @SortedHead, $HeadArrayRef->[0];
        @{$HeadArrayRef} = @SortedHead;
        @{$StatArrayRef} = @StatArrayNew;
    }

    # Translate the row description.
    if ( $Translation{UseAsValueSeries} && $Translation{UseAsValueSeries} ne 'Time' ) {
        for my $Word ( @{$StatArrayRef} ) {
            $Word->[0] = $LanguageObject->Translate( $Word->[0] );
        }
    }

    # Sort the row description.
    if ( $Sort{UseAsValueSeries} ) {

        # Special handling if the sumfunction is used.
        my $SumRowArrayRef;
        if ( $Param{StatRef}->{SumRow} ) {
            $SumRowArrayRef = pop @{$StatArrayRef};
        }

        my $DisableDefaultResultSort = grep { $_->{DisableDefaultResultSort} && $_->{DisableDefaultResultSort} == 1 }
            @{ $Param{StatRef}->{UseAsXvalue} };

        if ( !$DisableDefaultResultSort ) {
            @{$StatArrayRef} = sort { $a->[0] cmp $b->[0] } @{$StatArrayRef};
        }

        # Special handling if the sumfunction is used.
        if ( $Param{StatRef}->{SumRow} ) {
            push @{$StatArrayRef}, $SumRowArrayRef;
        }
    }

    unshift( @{$StatArrayRef}, $TitleArrayRef, $HeadArrayRef );

    return 1;
}

sub _WriteResultCache {
    my ( $Self, %Param ) = @_;

    my %GetParam = %{ $Param{GetParam} };

    if ( $GetParam{Year} && $GetParam{Month} ) {
        my $DateTimeObject    = $Kernel::OM->Create('Kernel::System::DateTime');
        my $DateTimeNowValues = $DateTimeObject->Get();

        my $DateTimeObjectParams = $Kernel::OM->Create(
            'Kernel::System::DateTime',
            ObjectParams => {
                Year   => $GetParam{Year},
                Month  => $GetParam{Month},
                Day    => $GetParam{Day},
                Hour   => $DateTimeNowValues->{Hour},
                Minute => $DateTimeNowValues->{Minute},
                Second => $DateTimeNowValues->{Second},
            }
        );

        # if get params in future do not cache
        return if ( !$DateTimeObject->Compare( DateTimeObject => $DateTimeObjectParams ) );
    }

    # write cache file
    my $Filename = $Self->_CreateStaticResultCacheFilename(
        GetParam => $Param{GetParam},
        StatID   => $Param{StatID},
    );

    $Self->_SetResultCache(
        Filename => $Filename,
        Result   => $Param{Data},
    );

    return 1;
}

=head2 _CreateStaticResultCacheFilename()

create a filename out of the GetParam information and the stat id

    my $Filename = $StatsObject->_CreateStaticResultCacheFilename(
        GetParam => {
            Year  => 2008,
            Month => 3,
            Day   => 5
        },
        StatID   => $Param{StatID},
    );

=cut

sub _CreateStaticResultCacheFilename {
    my ( $Self, %Param ) = @_;

    # check needed params
    for my $NeededParam (qw( StatID GetParam )) {
        if ( !$Param{$NeededParam} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $NeededParam!"
            );
            return;
        }
    }

    my $GetParamRef = $Param{GetParam};

    # format month and day params
    for my $TimeKey (qw(Month Day)) {
        if ( $GetParamRef->{$TimeKey} ) {
            $GetParamRef->{$TimeKey} = sprintf( "%02d", $GetParamRef->{$TimeKey} );
        }
    }

    my $Key = '';
    if ( $GetParamRef->{Year} ) {
        $Key .= $GetParamRef->{Year};
    }
    if ( $GetParamRef->{Month} ) {
        $Key .= "-$GetParamRef->{Month}";
    }
    if ( $GetParamRef->{Day} ) {
        $Key .= "-$GetParamRef->{Day}";
    }

    my $MD5Key = $Kernel::OM->Get('Kernel::System::Main')->FilenameCleanUp(
        Filename => $Key,
        Type     => 'md5',
    );

    return
        'Stats'
        . $Param{StatID} . '-'
        . $Kernel::OM->Get('Kernel::Language')->{UserLanguage} . '-'
        . $MD5Key
        . '.cache';
}

=head2 _SetResultCache()

cache the stats result with a given cache key (Filename).

    $StatsObject->_SetResultCache(
        Filename => 'Stats' . $Param{StatID} . '-' . $MD5Key . '.cache',
        Result   => $Param{Data},
    );

=cut

sub _SetResultCache {
    my ( $Self, %Param ) = @_;

    # check needed params
    for my $Needed (qw(Filename Result)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    $Kernel::OM->Get('Kernel::System::Cache')->Set(
        Type  => 'StatsRun',
        Key   => $Param{Filename},
        Value => $Param{Result},
        TTL   => 24 * 60 * 60,

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );

    return 1;
}

=head2 _GetResultCache()

get stats result from cache, if any

    my @Result = $StatsObject->_GetResultCache(
        Filename => 'Stats' . $Param{StatID} . '-' . $MD5Key . '.cache',
    );

=cut

sub _GetResultCache {
    my ( $Self, %Param ) = @_;

    # check needed params
    if ( !$Param{Filename} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => '_GetResultCache: Need Filename!',
        );
        return;
    }

    my $Cache = $Kernel::OM->Get('Kernel::System::Cache')->Get(
        Type => 'StatsRun',
        Key  => $Param{Filename},

        # Don't store complex structure in memory as it will be modified later.
        CacheInMemory => 0,
    );

    if ( ref $Cache ) {
        return @{$Cache};
    }

    return;
}

=head2 _DeleteCache()

clean up stats result cache.

=cut

sub _DeleteCache {
    my ( $Self, %Param ) = @_;

    return $Kernel::OM->Get('Kernel::System::Cache')->CleanUp(
        Type => 'Stats',
    );
}

sub _MonthArray {
    my @MonthArray = (
        '', 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec',
    );

    return \@MonthArray;
}

sub _AutomaticSampleImport {
    my ( $Self, %Param ) = @_;

    # Prevent deep recursions.
    local $Self->{InAutomaticSampleImport} = $Self->{InAutomaticSampleImport};
    return if $Self->{InAutomaticSampleImport}++;

    for my $Needed (qw(UserID)) {
        if ( !$Param{$Needed} ) {
            $Kernel::OM->Get('Kernel::System::Log')->Log(
                Priority => 'error',
                Message  => "Need $Needed!",
            );
            return;
        }
    }

    my $Language  = $Kernel::OM->Get('Kernel::Config')->Get('DefaultLanguage');
    my $Directory = $Self->{StatsTempDir};

    if ( !opendir( DIRE, $Directory ) ) {    ## no critic
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Can not open Directory: $Directory",
        );
        return;
    }

    # check if stats in the default language available, if not use en
    my $Flag = 0;
    while ( defined( my $Filename = readdir DIRE ) ) {
        if ( $Filename =~ m{^.*\.$Language\.xml$}x ) {
            $Flag = 1;
        }
    }

    rewinddir(DIRE);
    if ( !$Flag ) {
        $Language = 'en';
    }

    while ( defined( my $Filename = readdir DIRE ) ) {
        if ( $Filename =~ m{^.*\.$Language\.xml$}x ) {

            my $Filehandle;
            if ( !open $Filehandle, '<', $Directory . $Filename ) {    ## no critic
                $Kernel::OM->Get('Kernel::System::Log')->Log(
                    Priority => 'error',
                    Message  => "Can not open File: " . $Directory . $Filename,
                );
                closedir(DIRE);
                return;
            }

            my $Content = '';
            while (<$Filehandle>) {
                $Content .= $_;
            }
            close $Filehandle;

            my $StatID = $Self->Import(
                Content => $Content,
                UserID  => $Param{UserID},
            );
        }
    }
    closedir(DIRE);

    return 1;
}

=head2 _FromOTRSTimeZone()

Converts the given date/time string from OTRS time zone to the given time zone.

    my $String = $StatsObject->_FromOTRSTimeZone(
        String   => '2016-02-20 20:00:00',
        TimeZone => 'Europe/Berlin',
    );

Returns (example for OTRS time zone being set to UTC):

    $TimeStamp = '2016-02-20 21:00:00',

=cut

sub _FromOTRSTimeZone {
    my ( $Self, %Param ) = @_;

    # check needed params
    if ( !$Param{String} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need String!',
        );
        return;
    }

    return $Param{String} if !$Param{TimeZone};

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            String => $Param{String},
        },
    );
    $DateTimeObject->ToTimeZone( TimeZone => $Param{TimeZone} );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Error creating DateTime object.",
        );

        return;
    }

    return $DateTimeObject->ToString();
}

=head2 _ToOTRSTimeZone()

Converts the given date/time string from the given time zone to OTRS time zone.

    my $String = $StatsObject->_ToOTRSTimeZone(
        String    => '2016-02-20 18:00:00',
        TimeZone  => 'Europe/Berlin',
    );

Returns (example for OTRS time zone being set to UTC):

    $TimeStamp = '2016-02-20 17:00:00',

=cut

sub _ToOTRSTimeZone {
    my ( $Self, %Param ) = @_;

    # check needed params
    if ( !$Param{String} ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => 'Need String!',
        );
        return;
    }

    return $Param{String} if !$Param{TimeZone};

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => \%Param,
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => 'error',
            Message  => "Error creating DateTime object.",
        );

        return;
    }

    $DateTimeObject->ToOTRSTimeZone();

    return $DateTimeObject->ToString();
}

=head2 _GetCacheString()

returns a string that can be used for caching this particular statistic
with the given parameters.

    my $Result = $StatsObject->_GetCacheString(
        UseAsXvalue      => $UseAsXvalueRef
        UseAsValueSeries => $UseAsValueSeriesRef,
        UseAsRestriction => $UseAsRestrictionRef,
    );

=cut

sub _GetCacheString {
    my ( $Self, %Param ) = @_;

    # add the Language to the cache key
    my $Result = 'Language:' . $Kernel::OM->Get('Kernel::Language')->{UserLanguage};

    if ( $Param{TimeZone} ) {
        $Result .= 'TimeZone:' . $Param{TimeZone};
    }

    for my $Use (qw(UseAsXvalue UseAsValueSeries UseAsRestriction)) {
        $Result .= "$Use:";
        for my $Element ( @{ $Param{$Use} } ) {
            $Result .= "Name:$Element->{Name}:";
            if ( $Element->{Block} eq 'Time' ) {
                if ( $Element->{SelectedValues}[0] && $Element->{TimeScaleCount} ) {
                    $Result .= "TimeScaleUnit:$Element->{SelectedValues}[0]:";
                    $Result .= "TimeScaleCount:$Element->{TimeScaleCount}:";
                }

                if ( $Element->{TimeStart} && $Element->{TimeStop} ) {
                    $Result .= "TimeStart:$Element->{TimeStart}:TimeStop:$Element->{TimeStop}:";
                }
            }
            if ( $Element->{SelectedValues} ) {
                $Result .= "SelectedValues:" . join( ',', sort @{ $Element->{SelectedValues} } ) . ':';
            }
        }
    }

    # Convert to MD5 (not sure if this is needed any more).
    $Result = $Kernel::OM->Get('Kernel::System::Main')->FilenameCleanUp(
        Filename => $Result,
        Type     => 'md5',
    );

    return $Result;
}

=head2 _AddDeltaYMD()

Substitute for Date::Pcalc::Add_Delta_YMD() which uses Kernel::System::DateTime.

=cut

sub _AddDeltaYMD {
    my ( $Self, $Year, $Month, $Day, $YearsToAdd, $MonthsToAdd, $DaysToAdd ) = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => $Day,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return ( $Year, $Month, $Day, );
    }

    $DateTimeObject->Add(
        Years  => $YearsToAdd  || 0,
        Months => $MonthsToAdd || 0,
        Days   => $DaysToAdd   || 0,
    );
    my $DateTimeValues = $DateTimeObject->Get();

    return (
        $DateTimeValues->{Year},
        $DateTimeValues->{Month},
        $DateTimeValues->{Day},
    );
}

=head2 _AddDeltaDHMS()

Substitute for Date::Pcalc::Add_Delta_DHMS() which uses Kernel::System::DateTime.

=cut

sub _AddDeltaDHMS {
    my ( $Self, $Year, $Month, $Day, $Hour, $Minute, $Second, $DaysToAdd, $HoursToAdd, $MinutesToAdd, $SecondsToAdd )
        = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => $Day,
            Hour     => $Hour,
            Minute   => $Minute,
            Second   => $Second,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return ( $Year, $Month, $Day, $Hour, $Minute, $Second, );
    }

    $DateTimeObject->Add(
        Days    => $DaysToAdd    || 0,
        Hours   => $HoursToAdd   || 0,
        Minutes => $MinutesToAdd || 0,
        Seconds => $SecondsToAdd || 0,
    );
    my $DateTimeValues = $DateTimeObject->Get();

    return (
        $DateTimeValues->{Year},
        $DateTimeValues->{Month},
        $DateTimeValues->{Day},
        $DateTimeValues->{Hour},
        $DateTimeValues->{Minute},
        $DateTimeValues->{Second},
    );
}

=head2 _AddDeltaDays()

Substitute for Date::Pcalc::Add_Delta_Days() which uses Kernel::System::DateTime.

=cut

sub _AddDeltaDays {
    my ( $Self, $Year, $Month, $Day, $DaysToAdd ) = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => $Day,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return ( $Year, $Month, $Day, );
    }

    $DateTimeObject->Add(
        Days => $DaysToAdd || 0,
    );
    my $DateTimeValues = $DateTimeObject->Get();

    return (
        $DateTimeValues->{Year},
        $DateTimeValues->{Month},
        $DateTimeValues->{Day},
    );
}

=head2 _DaysInMonth()

Substitute for Date::Pcalc::Days_in_Month() which uses Kernel::System::DateTime.

=cut

sub _DaysInMonth {
    my ( $Self, $Year, $Month ) = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => 1,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return;
    }

    my $LastDayOfMonth = $DateTimeObject->LastDayOfMonthGet();

    return $LastDayOfMonth->{Day};
}

=head2 _DayOfWeek()

Substitute for Date::Pcalc::Day_of_Week() which uses Kernel::System::DateTime.

=cut

sub _DayOfWeek {
    my ( $Self, $Year, $Month, $Day ) = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => $Day,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return;
    }

    my $DateTimeValues = $DateTimeObject->Get();

    return $DateTimeValues->{DayOfWeek};
}

=head2 _DayOfWeekAbbreviation()

Substitute for Date::Pcalc::Day_of_Week_Abbreviation()

=cut

sub _DayOfWeekAbbreviation {
    my ( $Self, $DayOfWeek ) = @_;

    my %DayOfWeekAbbrs = (
        1 => 'Mon',
        2 => 'Tue',
        3 => 'Wed',
        4 => 'Thu',
        5 => 'Fri',
        6 => 'Sat',
        7 => 'Sun',
    );

    return if !$DayOfWeekAbbrs{$DayOfWeek};

    return $DayOfWeekAbbrs{$DayOfWeek};
}

=head2 _DayOfWeekToText()

Substitute for Date::Pcalc::Day_of_Week_to_Text()

=cut

sub _DayOfWeekToText {
    my ( $Self, $DayOfWeek ) = @_;

    my %DayOfWeekTexts = (
        1 => 'Monday',
        2 => 'Tuesday',
        3 => 'Wednesday',
        4 => 'Thursday',
        5 => 'Friday',
        6 => 'Saturday',
        7 => 'Sunday',
    );

    return if !$DayOfWeekTexts{$DayOfWeek};

    return $DayOfWeekTexts{$DayOfWeek};
}

=head2 _MondayOfWeek()

Substitute for Date::Pcalc::Monday_of_Week(), using Kernel::System::DateTime, note different parameters

=cut

sub _MondayOfWeek {
    my ( $Self, $Year, $Month, $Day ) = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => $Day,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return;
    }

    my $DateTimeValues = $DateTimeObject->Get();
    my $DaysToSubtract = $DateTimeValues->{DayOfWeek} - 1;

    if ($DaysToSubtract) {
        $DateTimeObject->Subtract( Days => $DaysToSubtract );
        $DateTimeValues = $DateTimeObject->Get();
    }

    return (
        $DateTimeValues->{Year},
        $DateTimeValues->{Month},
        $DateTimeValues->{Day},
    );
}

=head2 _WeekOfYear()

Substitute for Date::Pcalc::Week_of_Year(), using Kernel::System::DateTime

=cut

sub _WeekOfYear {
    my ( $Self, $Year, $Month, $Day ) = @_;

    my $DateTimeObject = $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            Year     => $Year,
            Month    => $Month,
            Day      => $Day,
            TimeZone => 'floating',
        },
    );

    if ( !$DateTimeObject ) {
        $Kernel::OM->Get('Kernel::System::Log')->Log(
            Priority => "error",
            Message  => "Error creating DateTime object.",
        );

        return;
    }

    return (
        $DateTimeObject->Format( Format => '%{week_number}' ),
        $DateTimeObject->Format( Format => '%{week_year}' ),
    );
}

=head2 _HumanReadableAgeGet()

Re-implementation of L<CustomerAge()|Kernel::Output::HTML::Layout/CustomerAge()> since this object is inaccessible from
the backend.

TODO: Currently, there is no support for translation of statistic values, it's planned to be implemented later on. For
the time being, this method will return a string in English only.

    my $HumanReadableAge = $StatsObject->_HumanReadableAgeGet(
        Age   => 360,
    );

Returns (converted seconds in human readable format, i.e. '1 d 2 h'):

    $HumanReadableAge = '6 h',

=cut

sub _HumanReadableAgeGet {
    my ( $Self, %Param ) = @_;

    my $ConfigObject = $Kernel::OM->Get('Kernel::Config');

    my $Age       = defined( $Param{Age} ) ? $Param{Age} : return;
    my $AgeStrg   = '';
    my $DayDsc    = 'd';
    my $HourDsc   = 'h';
    my $MinuteDsc = 'm';
    if ( $ConfigObject->Get('TimeShowCompleteDescription') ) {
        $DayDsc    = 'day(s)';
        $HourDsc   = 'hour(s)';
        $MinuteDsc = 'minute(s)';
    }
    if ( $Age =~ /^-(.*)/ ) {
        $Age     = $1;
        $AgeStrg = '-';
    }

    # get days
    if ( $Age >= 86400 ) {
        $AgeStrg .= int( ( $Age / 3600 ) / 24 ) . ' ';
        $AgeStrg .= $DayDsc . ' ';
    }

    # get hours
    if ( $Age >= 3600 ) {
        $AgeStrg .= int( ( $Age / 3600 ) % 24 ) . ' ';
        $AgeStrg .= $HourDsc . ' ';
    }

    # get minutes (just if age < 1 day)
    if ( $ConfigObject->Get('TimeShowAlwaysLong') || $Age < 86400 ) {
        $AgeStrg .= int( ( $Age / 60 ) % 60 ) . ' ';
        $AgeStrg .= $MinuteDsc;
    }

    $AgeStrg =~ s/\s+$//;

    return $AgeStrg;
}

=head2 _TimeStamp2DateTime

Return a datetime object from a timestamp.

=cut

sub _TimeStamp2DateTime {
    my ( $Self, %Param, ) = @_;

    my $TimeStamp = $Param{TimeStamp};
    return $Kernel::OM->Create(
        'Kernel::System::DateTime',
        ObjectParams => {
            String => $TimeStamp,
        },
    );
}

1;

=head1 TERMS AND CONDITIONS

This software is part of the OTRS project (L<https://otrs.org/>).

This software comes with ABSOLUTELY NO WARRANTY. For details, see
the enclosed file COPYING for license information (GPL). If you
did not receive this file, see L<https://www.gnu.org/licenses/gpl-3.0.txt>.

=cut
