Question Optimisation d'un script

# =======================================================
# NAME: auditAD.ps1
# AUTHOR: xxxxxx
# DATE: 22/12/2020
##
# 
# This script is used to created HTML report for Active directory Audit
# =======================================================
#   18/04/2020 
# -Add last update times for all DC
#   22/04/2020
# -Optimisation code get-recyclebinstate
# -Suppression de nombreuses variables à l'intérieur des fonction
# -Suppression des return des fonctions
#....

#Requires -Version 3.0
#Requires -Modules ActiveDirectory,GroupPolicy

################Global Variables #####################


#region HTML style
$HTMLCSS=@"
<style>
table {
   # border-collapse: collapse;
   border-width: 1px; border-style: solid; border-color: black; border-collapse: collapse;
}
h2 {text-align:center}
th, td {
    #padding: 8px;
    #text-align: left;
    #border-bottom: 1px solid #ddd;
    border-width: 1px; padding: 3px; border-style: solid; border-color: black;
}
body {
    font-family:"Vinci Sans Light";Font-Size:10pt 
}

tr:hover{background-color:#f5f5f5}
</style>
"@

#Variable initialization  
#$domainName = All forest domains
#$ReportPath = Path where script datas will be stored
#$date = Current date to format text and be sure they are unique
#$dnsfilename is dns file name for dns configuration
#$usersCSV is file name for exported users in each domain
#$computerCSV is file name for exported computers in each domains
#$logfilename is file name for file contains script log for troubleshoot.
$domainName=(get-adforest).domains
$ReportPath = "c:\temp\audit"
$date = (get-date -Format "dd_MM_yyyy_HH_mm")
$htmlReportFileName = "ADReport_$date.html"
$DNSFileName = "Dns_$date.txt"
$usersCSV = "users_$date.csv"
$computersCSV = "computers_$date.csv"

$logFileName = "AuditADps1_$date.log"


################ Functions #####################

#region globalcatalogs
#Check if DCs are Global Catalogs 
Function Get-GlobalCatalogServers
{
    param (
        [string]$domain 
    )
    $DCsInDomain = Get-ADDomainController -Filter * -Server $domain
    Write-EZLog -Category INF -Message "### Start Get-GlobalCatalogServers ###"
    Write-EZLog -Category INF -Message "get DC globalcataog"
    foreach ($DC in $DCsInDomain)
    {
        Write-EZLog -Category INF -Message "Test $($DC.hostname)"
        [PSCustomObject]@{
            ServerName = $DC.hostname
            IsGlobalCatalog = $DC.IsGlobalCatalog
        }
    }
    Write-EZLog -Category INF -Message "object created. ServerName = $($obj.ServerName) ; IsGlobalCatalog = $($obj.IsGlobalCatalog)"
    Write-EZLog -Category INF -Message "End Test $($DC.hostname)"
    Write-EZLog -Category INF -Message "### End Get-GlobalCatalogServers ###"
} 

#function to check last time AD partitions were backuped
#Source : https://adamtheautomator.com/last-backup-domain-controller/

#Find 1 DC in domain and ask it for the last backup date.
#This script give last backup for AD and not for the server because attribute is updated each time backup happens.
function Get-LastBackupDate
{
    param (
        [string]$domain 
    )
    #Find 1 domain controller in current domain
    $DomainDC = @(Get-ADDomainController -Filter {domain -eq $domain} -Server $domain)
    [PSCustomObject]@{
        DomainName = $domain
        LastBackupDate = (Get-ADReplicationAttributeMetadata -Object (get-addomain $domain).distinguishedname -Properties dsasignature -Server $DomainDC[0].hostname).LastOriginatingChangeTime
    }
}


#region hardware DC configuration
#Hardware Configuration of all DCs (Logical CPU number,RAM, physical or virtual, OS, last boot)
function Get-AllDCHardware
{
    param (
        [string]$domain 
    )
    Write-EZLog -Category INF -Message "### Start Get-AllDCHardware ###"

    (Get-ADDomainController -Filter {domain -eq $domain} -Server $domain) | Foreach-Object {
        Write-EZLog -Category INF -Message "Process Domain controller $($_.hostname)"
           [PSCustomObject]@{
            ServerName = $_.name
            LogicalCPUNb = (Get-CimInstance win32_computersystem -ComputerName $_.hostname).numberOfLogicalProcessors
            'RAM(GB)' = (Get-CimInstance win32_computersystem -ComputerName $_.hostname).TotalPhysicalMemory/1GB -as [INT]
            Type = (get-CimInstance win32_computersystem -ComputerName $_.hostname).model
            OS = (Get-CimInstance Win32_OperatingSystem -ComputerName $_.hostname).caption
            LastBoot = (Get-CimInstance -ClassName win32_operatingsystem -ComputerName $_.hostname).lastbootuptime
        }
        Write-EZLog -Category INF -Message "object created. ServerName = $($obj.ServerName) ; LogicalCPUNb = $($obj.LogicalCPUNb) ; RAM(GB) = $($obj.'RAM(GB)')"
        Write-EZLog -Category INF -Message "Type = $($obj.Type) ; OS = $($obj.OS) ; LastBoot = $($obj.LastBoot)"
        Write-EZLog -Category INF -Message "End Domain controller $($_.hostname)"
    }
    Write-EZLog -Category INF -Message "### End Get-AllDCHardware ###"
}
#endregion



################ HTML Build function #####################
<#
.Synopsis
   Generate HTML report
.DESCRIPTION
   Use all variable to build html report with CSS style written on the top of this page
.EXAMPLE
   Get-HTMLReport -Path "c:\temp\report.html"
#>
function Get-HTMLReport
{
    [CmdletBinding()]

    Param
    (
        #HTML file path
        [Parameter(Mandatory=$true)]
        [string] $Path,

        #HTML file name
        [Parameter(Mandatory=$true)]
        [string] $FileName
    )
    begin   
    {
        if(!(Test-Path $Path))
        {
            New-Item -Path $Path -ItemType directory
        }
        $HTMLfilename="$path\$filename.html"
    }
    process
    {
    #HTML generation

    $HTMLTitle = "<h1>Active Directory Report for domain $domain</h1>"



    $LastBackupDate = $LastBackupDate | ConvertTo-Html -Fragment
    $GlobalCatalogServers = $GlobalCatalogServers | ConvertTo-Html -Fragment
    $DCHardware = $DCHardware | ConvertTo-Html -Fragment

    #region HTML body

    $HTML = @"
    <!DOCTYPE html>
    <html>
    <head>
    <title>Report</title>
    <meta name="generator" content="PowerShell" />
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">

    $HTMLCSS
    </head>
    <body>
    $HTMLTitle
    
    <h3> Global Catalogs </h3>
    $GlobalCatalogServers

    <h3> Last Backup Date</h3>
    $LastBackupDate

    <h3>Hardware configuration</h3>
    $DCHardware <br />
    
    $End Date $(get-date -Format "dd/MM/yyyy HH:mm")
    </body>
    </html>
"@

    $HTML | out-file -FilePath $HTMLfilename
    #endregion

    Invoke-Item $HTMLfilename

    }
}

################ Main #####################
#region main function
###### Exécution des commandes

#Create working directory c:\temp\audit folder
if (-not(Test-Path $ReportPath))
{
    New-Item -Path $ReportPath -Type Directory | Out-Null
}

Write-EZLog -Header -LogFile "$ReportPath\$logFileName"


foreach ($domain in (Get-ADForest).domains)
{
    Write-EZLog -Category INF -Message "-------------- Start domain $domain --------------" -ToScreen

    Write-EZLog -Category INF -Message "Test ReportFolder exist" -ToScreen

    if (-not(Test-Path $ReportPath\$domain))
    {
        New-Item -Path "$ReportPath\$domain" -Type Directory | Out-Null
    }
	Write-EZLog -Category INF -Message "GlobalCatalogServers" -ToScreen
    $GlobalCatalogServers = Get-GlobalCatalogServers -domain $domain
    Write-EZLog -Category INF -Message "LastBackupDate" -ToScreen
    $LastBackupDate = Get-LastBackupDate -domain $domain
    Write-EZLog -Category INF -Message "DCHardware" -ToScreen
    $DCHardware = Get-AllDCHardware -domain $domain
	
	
    #End
    Write-EZLog -Category INF -Message "----End to Export Files----" -ToScreen
    Write-EZLog -Category INF -Message "Build HTML report" -ToScreen
    Get-HTMLReport -Path "$ReportPath\$domain" -FileName "$($domain)_$htmlReportFileName"
    Write-EZLog -Category INF -Message "-------------- End domain $domain --------------" -ToScreen

}
#endregion

function Get-LastBackupDate
{
    param (
        [string]$domain 
    )
$obj=@()
    #Find 1 domain controller in current domain
    $DomainDC = @(Get-ADDomainController -Filter {domain -eq $domain} -Server $domain)
   $obj+= [PSCustomObject]@{
        DomainName = $domain
        LastBackupDate = (Get-ADReplicationAttributeMetadata -Object (get-addomain $domain).distinguishedname -Properties dsasignature -Server $DomainDC[0].hostname).LastOriginatingChangeTime
    }
  Write-EZLog -Category INF -Message "object created. DomainName = $($obj.DomainName ) ; LastBackupDate = $($obj.LastBackupDate )"
}

Write-EZLog -Category INF -Message "object created. DomainName = $($obj.DomainName ) ; LastBackupDate = $($obj.LastBackupDate )"