<#
.SYNOPSIS
    This script configures the basic settings for an Active Directory Domain Services (ADDS) environment.
    It enables the Recycle Bin feature, creates a basic Organizational Unit (OU) structure, and logs the configuration process.
    The script also generates a summary file with the configuration details.

.DESCRIPTION
    The script performs the following tasks:

    1. Checks if the server is part of a domain and if the required PowerShell modules are available.
    2. Enables the Recycle Bin feature if it's not already enabled.
    3. Creates a basic OU structure with the following OUs: Users, Groups, Computers, Servers, Service Accounts, and Administrators.
    4. Logs the configuration process to a log file.
    5. Generates a summary file with the configuration details.

.PARAMETER None
    This script does not require any parameters.

.EXAMPLE
    Run the script in PowerShell to configure the ADDS environment.

.NOTES
    This script is intended for use in a test or production environment. Make sure to test the script in a non-production environment before running it in production.
    Author: D.de Kooker - info@dcomputers.nl
    Version: 1.0

    DISCLAIMER: Use scripts at your own risk, if there is anything I can help you with I will try but I do not take responsibility for the way that anyone else uses my scripts.
    Sharing is caring. Share your knowledge with the world so that everybody can learn from it.

.LINK
    The latest version can Always be found on my GIT page on the link below: 
    https://git.dcomputers.nl/Dcomputers/PowershellScripts
#>

#region Global script settings and variables
    $Version = "v1.0"
    $logfilelocation = "$($MyInvocation.MyCommand.Path | Split-Path -Parent)\Logs"
    $logfilename = "$(Get-Date -Format yyyyMMddHHmmss)-ADDS_Configuration.log"
    $summaryfilename = "$(Get-Date -Format yyyyMMddHHmmss)-ADDS_Configuration_Summary.txt"
#endregion

#region functions
    function Initiate-Log {
        # Get current user and session information
        $username = [System.Security.Principal.WindowsIdentity]::GetCurrent().Name
        $computerName = $env:COMPUTERNAME
        $sessionID = $pid
        $date = Get-Date -Format "yyyy-MM-dd HH:mm:ss"

        # Write log header
        $logHeader = "[$date] Log initiated by $username on $computerName (Session ID: $sessionID)"
        Add-Content -Path $logfilelocation\$logfilename -Value "**********************"
        Add-Content -Path $logfilelocation\$logfilename -Value "LogFile initiation"
        Add-Content -Path $logfilelocation\$logfilename -Value "Start time: $date"
        Add-Content -Path $logfilelocation\$logfilename -Value "Username: $username"
        Add-Content -Path $logfilelocation\$logfilename -Value "Machine: $computerName"
        Add-Content -Path $logfilelocation\$logfilename -Value "Process ID: $sessionID"
        Add-Content -Path $logfilelocation\$logfilename -Value "Script Version: $Version"
        Add-Content -Path $logfilelocation\$logfilename -Value "Script Source: https://git.dcomputers.nl/Dcomputers/PowershellScripts"
        Add-Content -Path $logfilelocation\$logfilename -Value "**********************"
    }

    function Write-Log {
        [CmdletBinding()]
        Param (
            [Parameter(Mandatory=$true)]
            [string]$Message,
            [Parameter(Mandatory=$false)]
            [ValidateSet("INFO", "WARNING", "ERROR")]
            [string]$Level = "INFO"
        )
        $timestamp = Get-Date -Format "yyyy-MM-dd HH:mm:ss"
        $logmessage = "[$timestamp] [$Level] $Message"
        Add-Content -Path $logfilelocation\$logfilename -Value $logmessage
    }

    function Write-Summary {
        [CmdletBinding()]
        Param (
            [Parameter(Mandatory=$true)]
            [string]$Message
        )
        Add-Content -Path $logfilelocation\$summaryfilename -Value $Message
    }
#endregion

#region prerequisites check
    #Create log directory if not present and initiate logfile
    if (!(test-path $logfilelocation)) {mkdir $logfilelocation}
    Initiate-Log

    #Check if the required Powershell Modules are available
    $modules = @("ActiveDirectory","DnsServer")
    foreach ($module in $modules) {
        if (!(Get-Module -Name $module -ListAvailable)) {
            Write-Host "The $module module is not installed. Please install it and try again."
            Write-Log -Message "The $module module is not installed. Please install it and try again." -Level ERROR
            exit 1
        }
        else {
            Import-Module $module
        }
    }

    #Check if the server is part of a domain
    $domainController = Get-ADDomainController -ErrorAction SilentlyContinue
    if (-not $domainController) {
        Write-Host "The local server is not part of a domain."
        Write-Log -Message "The local server is not part of a domain." -Level ERROR
        exit 1
    } else {
        Write-Host "The local server is part of the $($domainController.Site) site in the $($domainController.Domain) domain."
        Write-Log -Message "The local server is part of the $($domainController.Site) site in the $($domainController.Domain) domain." -Level INFO
    }
#endregion
    
#region configure ADDS
    #Enable Recycle bin
    $recycleBinFeature = Get-ADOptionalFeature -Filter {Name -eq "Recycle Bin Feature"} -ErrorAction SilentlyContinue
    if (-not $recycleBinFeature.EnabledScopes) {
        Write-Host "The Recycle Bin feature is not enabled. Enabling it..."
        Write-Log -Message "The Recycle Bin feature is not enabled. Enabling it..." -Level INFO
        Enable-ADOptionalFeature -Identity "Recycle Bin Feature" -Scope ForestOrConfigurationSet -Target $domainController.Domain -Confirm:$false
        Write-Host "The Recycle Bin feature has been enabled."
        Write-Log -Message "The Recycle Bin feature has been enabled." -Level INFO
    } else {
        Write-Host "The Recycle Bin feature is already enabled."
        Write-Log -Message "The Recycle Bin feature is already enabled." -Level INFO
    }

    #Create a basic OU structure
    $companyName = Read-Host "Please enter the company name"
    $rootOU = Get-ADOrganizationalUnit -Filter {Name -eq $companyName} -ErrorAction SilentlyContinue
    if (-not $rootOU) {
        $rootOU = New-ADOrganizationalUnit -Name $companyName -Path $domainController.DefaultPartition -ProtectedFromAccidentalDeletion $true
        Write-Host "The root OU '$companyName' has been created."
        Write-Log -Message "The root OU '$companyName' has been created." -Level INFO
    } else {
        Write-Host "The root OU '$companyName' already exists."
        Write-Log -Message "The root OU '$companyName' already exists." -Level INFO
    }

    $ouList = @("Users", "Groups", "Computers", "Servers", "Service Accounts", "Administrators")
    $rootOU = Get-ADOrganizationalUnit -Filter {Name -eq $companyName} -ErrorAction SilentlyContinue
    foreach ($ou in $ouList) {
        $newOU = Get-ADOrganizationalUnit -Filter "Name -eq '$ou' -and DistinguishedName -like '*,$($companyName),$($domainController.DefaultPartition)'" -ErrorAction SilentlyContinue
        if (-not $newOU) {
            $newOU = New-ADOrganizationalUnit -Name $ou -Path $rootOU.DistinguishedName -ProtectedFromAccidentalDeletion $true
            Write-Host "The OU '$ou' has been created under '$companyName'."
            Write-Log -Message "The OU '$ou' has been created under '$companyName'."
        } else {
            Write-Host "The OU '$ou' already exists under '$companyName'."
            Write-Log -Message "The OU '$ou' already exists under '$companyName'."
        }
    }
    Write-Host "The basic OU structure has been created or already exists."
    Write-Log -Message "The basic OU structure has been created or already exists."
#endregion

#region summary
    Write-Summary "ADDS Structure configuration Summary:"
    Write-Summary "---------------------------"
    Write-Summary "Configuration date: $(Get-Date -Format "dd-MM-yyy HH:mm:ss")"
    Write-Summary "Company Name: $companyName"
    Write-Summary "Domain: $($domainController.Domain)"
    Write-Summary "Site: $($domainController.Site)"
    Write-Summary "Recycle Bin: Enabled"
    Write-Summary "OU Structure: Created or already exists"
    Write-Summary "---------------------------"
#endregion