# Ensure ImportExcel module is installed
if (-not (Get-Module -ListAvailable -Name ImportExcel)) {
    Write-Host "📦 ImportExcel module not found. Installing..."
    Install-Module -Name ImportExcel -Scope CurrentUser -Force
} else {
    Write-Host "✅ ImportExcel module is already installed."
}

# Ensure ExchangeOnlineManagement module is installed
if (-not (Get-Module -ListAvailable -Name ExchangeOnlineManagement)) {
    Write-Host "📦 ExchangeOnlineManagement module not found. Installing..."
    Install-Module -Name ExchangeOnlineManagement -Scope CurrentUser -Force
} else {
    Write-Host "✅ ExchangeOnlineManagement module is already installed."
}

# Output Excel file path
$excelPath = "C:\Temp\AuditLoggingStatus.xlsx"

# Ensure output folder exists
if (!(Test-Path -Path "C:\Temp")) {
    New-Item -Path "C:\" -Name "Temp" -ItemType Directory | Out-Null
}

# Connect to Exchange Online
Connect-ExchangeOnline

# === 1. Check Unified Audit Logging (UAL) status ===
Write-Host "`n=== Unified Audit Logging Status ==="
$ualStatus = Get-AdminAuditLogConfig
$ualResult = [PSCustomObject]@{
    Setting     = "Unified Audit Log Enabled"
    Value       = $ualStatus.UnifiedAuditLogIngestionEnabled
    Description = if ($ualStatus.UnifiedAuditLogIngestionEnabled) { "✅ UAL is ENABLED" } else { "❌ UAL is DISABLED" }
}

# === 2. Check mailbox audit logging for each user ===
Write-Host "`n=== Mailbox Audit Logging Status (per mailbox) ==="
$mailboxAuditResults = @()

$mailboxes = Get-Mailbox -ResultSize Unlimited -RecipientTypeDetails UserMailbox

foreach ($mbx in $mailboxes) {
    try {
        $audit = Get-Mailbox -Identity $mbx.Identity | Select-Object DisplayName, AuditEnabled, AuditLogAgeLimit
        $mailboxAuditResults += [PSCustomObject]@{
            DisplayName      = $audit.DisplayName
            AuditEnabled     = $audit.AuditEnabled
            AuditLogAgeLimit = $audit.AuditLogAgeLimit
            Status           = if ($audit.AuditEnabled) { "✅ Enabled" } else { "❌ Disabled" }
        }
    } catch {
        Write-Warning "Failed to get audit info for $($mbx.DisplayName): $_"
    }
}

# === 3. Export both results to Excel ===
$ualResult | Export-Excel -Path $excelPath -WorksheetName "Unified Audit Log" -AutoSize
$mailboxAuditResults | Export-Excel -Path $excelPath -WorksheetName "Mailbox Audit Logging" -AutoSize

Write-Host "`n✅ Report exported to $excelPath"

# === 4. Disconnect ===
Disconnect-ExchangeOnline -Confirm:$false

# === 5. Clear cached credentials to force reauthentication next time ===
Remove-Item "$env:USERPROFILE\.ExchangeOnline\TokenCache" -Force -ErrorAction SilentlyContinue
Write-Host "`n🧹 Cached credentials cleared. Reauthentication will be required on next run."