if (-not ([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
    Write-Error "Exécutez ce script en tant qu'administrateur."
    exit 1
}

$ScopeName = 'LAN_EntrepriseXYZ'
$StartIP = '192.168.147.200'
$EndIP = '192.168.147.220'
$SubnetMask = '255.255.255.0'
$ScopeId = '192.168.147.0'
$DnsServer = '192.168.147.10'
$Router = '192.168.147.1'
$Domain = 'entreprisexyz.local'
$ResName = 'Admin-PC'
$ResIP = '192.168.147.201'
$ResMac = '00-11-22-33-44-55'


$dhcpFeature = Get-WindowsFeature -Name 'DHCP'
if (-not $dhcpFeature.Installed) {
    Write-Host "Installation du rôle DHCP..."
    Install-WindowsFeature -Name 'DHCP' -IncludeManagementTools -ErrorAction Stop | Out-Null
    Write-Host "Rôle DHCP installé." -ForegroundColor Green
}

try {
    if (-not (Get-DhcpServerv4Scope -ScopeId $ScopeId -ErrorAction SilentlyContinue)) {
        Add-DhcpServerv4Scope -Name $ScopeName -StartRange $StartIP -EndRange $EndIP -SubnetMask $SubnetMask -State Active -LeaseDuration (New-TimeSpan -Days 8) -ErrorAction Stop
        Write-Host "Étendue '$ScopeName' créée : $StartIP - $EndIP"
    }
    else {
        Write-Host "Étendue '$ScopeName' existe déjà."
    }

    Set-DhcpServerv4OptionValue -ScopeId $ScopeId -DnsServer $DnsServer -Router $Router -DnsDomain $Domain -ErrorAction Stop
    Write-Host "Options DHCP configurées : DNS=$DnsServer, Passerelle=$Router, Domaine=$Domain"

    Add-DhcpServerv4Reservation -ScopeId $ScopeId -IPAddress $ResIP -ClientId $ResMac -Name $ResName -Description 'Réservation poste administratif' -ErrorAction Stop
    Write-Host "Réservation ajoutée : $ResName -> $ResIP ($ResMac)"
}
catch {
    Write-Warning "Opération échouée : $_"
}