<#
.SYNOPSIS
    Windows-Wartungsskript - bereinigt Temp, Caches, Logs, WU-Cache, Papierkorb usw.

.DESCRIPTION
    Laeuft lokal auf Clients und Servern. Schreibt ein ausfuehrliches Transcript-Log
    nach C:\ProgramData\Maintenance\Logs und gibt ein Stats-Objekt zurueck, das vom
    zentralen Runner aggregiert werden kann.

.PARAMETER MinFileAgeDays
    Dateien, die juenger als X Tage sind, werden ausgelassen (Default 1).

.PARAMETER SkipDISM
    Ueberspringt DISM /StartComponentCleanup /ResetBase (langlaufend, irreversibel).

.PARAMETER SkipCleanMgr
    Ueberspringt cleanmgr /sagerun:1.

.PARAMETER SkipBrowserCache
    Ueberspringt Edge/Chrome/Firefox-Caches.

.PARAMETER LogRoot
    Zielverzeichnis fuer Logs (Default C:\ProgramData\Maintenance\Logs).

.EXAMPLE
    .\Invoke-Maintenance.ps1
    .\Invoke-Maintenance.ps1 -SkipDISM -SkipCleanMgr
#>
[CmdletBinding()]
param(
    [int]$MinFileAgeDays = 1,
    [switch]$SkipDISM,
    [switch]$SkipCleanMgr,
    [switch]$SkipBrowserCache,
    [string]$LogRoot = "C:\ProgramData\Maintenance\Logs"
)

#region --- Setup ---------------------------------------------------------------
$ErrorActionPreference = 'Continue'
$ProgressPreference    = 'SilentlyContinue'

if (-not (Test-Path $LogRoot)) { New-Item -ItemType Directory -Path $LogRoot -Force | Out-Null }
$stamp     = Get-Date -Format 'yyyyMMdd_HHmmss'
$hostName  = $env:COMPUTERNAME
$logFile   = Join-Path $LogRoot "$hostName`_$stamp.log"
$statsFile = Join-Path $LogRoot "$hostName`_$stamp.stats.json"

Start-Transcript -Path $logFile -Force | Out-Null

$script:Stats = [ordered]@{
    ComputerName = $hostName
    StartedAt    = (Get-Date).ToString('s')
    Steps        = @()
    TotalFreedMB = 0
    Errors       = 0
}

function Write-Section($Title) {
    Write-Host ""
    Write-Host ("=" * 78)
    Write-Host (" {0}" -f $Title)
    Write-Host ("=" * 78)
}

function Get-FolderSizeMB {
    param([string]$Path)
    if (-not (Test-Path -LiteralPath $Path)) { return 0 }
    try {
        $sum = (Get-ChildItem -LiteralPath $Path -Recurse -Force -ErrorAction SilentlyContinue |
                Measure-Object -Property Length -Sum).Sum
        if ($null -eq $sum) { return 0 }
        return [math]::Round($sum / 1MB, 2)
    } catch { return 0 }
}

function Remove-ContentSafely {
    <#
        Loescht den Inhalt eines Ordners, ueberspringt gesperrte Dateien,
        respektiert MinFileAgeDays. Gibt freigegebene MB zurueck.
    #>
    param(
        [Parameter(Mandatory)] [string]$Path,
        [int]$MinAgeDays = $MinFileAgeDays
    )
    if (-not (Test-Path -LiteralPath $Path)) { return 0 }
    $before  = Get-FolderSizeMB -Path $Path
    $cutoff  = (Get-Date).AddDays(-$MinAgeDays)
    $deleted = 0; $skipped = 0
    Get-ChildItem -LiteralPath $Path -Force -Recurse -ErrorAction SilentlyContinue |
        Where-Object { -not $_.PSIsContainer -and $_.LastWriteTime -lt $cutoff } |
        ForEach-Object {
            try { Remove-Item -LiteralPath $_.FullName -Force -ErrorAction Stop; $deleted++ }
            catch { $skipped++ }
        }
    # Leere Unterordner entfernen
    Get-ChildItem -LiteralPath $Path -Force -Recurse -Directory -ErrorAction SilentlyContinue |
        Sort-Object FullName -Descending |
        ForEach-Object {
            if (-not (Get-ChildItem -LiteralPath $_.FullName -Force -ErrorAction SilentlyContinue)) {
                try { Remove-Item -LiteralPath $_.FullName -Force -ErrorAction Stop } catch {}
            }
        }
    $after  = Get-FolderSizeMB -Path $Path
    $freed  = [math]::Max(0, $before - $after)
    Write-Host ("  {0}: -{1} MB (vorher {2} MB, gesperrt: {3})" -f $Path, $freed, $before, $skipped)
    return $freed
}

function Add-Step($Name, $FreedMB, $Note = "") {
    $script:Stats.Steps += [pscustomobject]@{
        Step    = $Name
        FreedMB = [math]::Round($FreedMB, 2)
        Note    = $Note
    }
    $script:Stats.TotalFreedMB = [math]::Round($script:Stats.TotalFreedMB + $FreedMB, 2)
}
#endregion

Write-Section "Windows-Wartung auf $hostName  -  $stamp"

#region --- 1. Windows Temp ----------------------------------------------------
Write-Section "1. Windows Temp"
$f = 0
$f += Remove-ContentSafely -Path "$env:windir\Temp"
$f += Remove-ContentSafely -Path "$env:SystemDrive\Temp" -MinAgeDays $MinFileAgeDays
Add-Step "WindowsTemp" $f
#endregion

#region --- 2. User Temps / Caches --------------------------------------------
Write-Section "2. User Temps / Caches (alle Profile)"
$f = 0
$profiles = Get-ChildItem 'C:\Users' -Directory -Force -ErrorAction SilentlyContinue |
            Where-Object { $_.Name -notin @('Public','Default','Default User','All Users') }
foreach ($p in $profiles) {
    $targets = @(
        "$($p.FullName)\AppData\Local\Temp",
        "$($p.FullName)\AppData\Local\Microsoft\Windows\INetCache",
        "$($p.FullName)\AppData\Local\Microsoft\Windows\WebCache",
        "$($p.FullName)\AppData\Local\Microsoft\Windows\Explorer"   # Thumbnail-Cache
    )
    foreach ($t in $targets) { $f += Remove-ContentSafely -Path $t }
}
Add-Step "UserTemps" $f
#endregion

#region --- 3. Browser-Caches --------------------------------------------------
if (-not $SkipBrowserCache) {
    Write-Section "3. Browser-Caches (Edge / Chrome / Firefox)"
    $f = 0
    foreach ($p in $profiles) {
        $browserPaths = @(
            "$($p.FullName)\AppData\Local\Microsoft\Edge\User Data\Default\Cache",
            "$($p.FullName)\AppData\Local\Microsoft\Edge\User Data\Default\Code Cache",
            "$($p.FullName)\AppData\Local\Google\Chrome\User Data\Default\Cache",
            "$($p.FullName)\AppData\Local\Google\Chrome\User Data\Default\Code Cache"
        )
        foreach ($b in $browserPaths) { $f += Remove-ContentSafely -Path $b }
        # Firefox: Cache liegt unter zufaelligem Profilordner
        $ffRoot = "$($p.FullName)\AppData\Local\Mozilla\Firefox\Profiles"
        if (Test-Path $ffRoot) {
            Get-ChildItem $ffRoot -Directory -ErrorAction SilentlyContinue | ForEach-Object {
                $f += Remove-ContentSafely -Path (Join-Path $_.FullName 'cache2')
            }
        }
    }
    Add-Step "BrowserCaches" $f
}
#endregion

#region --- 4. Windows Update Cache -------------------------------------------
Write-Section "4. Windows Update Cache (SoftwareDistribution\Download)"
$f = 0
try {
    Stop-Service -Name wuauserv,bits,cryptsvc -Force -ErrorAction SilentlyContinue
    Start-Sleep -Seconds 2
    $f = Remove-ContentSafely -Path "$env:windir\SoftwareDistribution\Download" -MinAgeDays 0
} finally {
    Start-Service -Name wuauserv,bits,cryptsvc -ErrorAction SilentlyContinue
}
Add-Step "WindowsUpdateCache" $f
#endregion

#region --- 5. CBS / Panther / Setup-Logs -------------------------------------
Write-Section "5. CBS / Panther / Setup-Logs"
$f = 0
$f += Remove-ContentSafely -Path "$env:windir\Logs\CBS"        -MinAgeDays 7
$f += Remove-ContentSafely -Path "$env:windir\Panther"         -MinAgeDays 7
$f += Remove-ContentSafely -Path "$env:windir\Logs\DISM"       -MinAgeDays 7
$f += Remove-ContentSafely -Path "$env:windir\Logs\WindowsUpdate" -MinAgeDays 7
Add-Step "SystemLogs" $f
#endregion

#region --- 6. Prefetch --------------------------------------------------------
Write-Section "6. Prefetch"
$f = Remove-ContentSafely -Path "$env:windir\Prefetch" -MinAgeDays 7
Add-Step "Prefetch" $f
#endregion

#region --- 7. Delivery Optimization Cache ------------------------------------
Write-Section "7. Delivery Optimization Cache"
$f = Remove-ContentSafely -Path "$env:windir\ServiceProfiles\NetworkService\AppData\Local\Microsoft\Windows\DeliveryOptimization\Cache" -MinAgeDays 0
Add-Step "DeliveryOptimization" $f
#endregion

#region --- 8. WER / CrashDumps -----------------------------------------------
Write-Section "8. WER / CrashDumps / MEMORY.DMP"
$f = 0
$f += Remove-ContentSafely -Path "$env:ProgramData\Microsoft\Windows\WER\ReportQueue"    -MinAgeDays 1
$f += Remove-ContentSafely -Path "$env:ProgramData\Microsoft\Windows\WER\ReportArchive"  -MinAgeDays 7
$f += Remove-ContentSafely -Path "$env:ProgramData\Microsoft\Windows\WER\Temp"           -MinAgeDays 1
$f += Remove-ContentSafely -Path "$env:LOCALAPPDATA\CrashDumps"                          -MinAgeDays 7
if (Test-Path "$env:windir\MEMORY.DMP") {
    $sz = (Get-Item "$env:windir\MEMORY.DMP").Length / 1MB
    try { Remove-Item "$env:windir\MEMORY.DMP" -Force -ErrorAction Stop; $f += $sz } catch {}
}
$f += Remove-ContentSafely -Path "$env:windir\Minidump" -MinAgeDays 7
Add-Step "CrashDumps" $f
#endregion

#region --- 9. IIS-Logs (falls vorhanden) -------------------------------------
if (Test-Path "$env:SystemDrive\inetpub\logs\LogFiles") {
    Write-Section "9. IIS-Logs (aelter 30 Tage)"
    $cutoff = (Get-Date).AddDays(-30)
    $f = 0; $before = Get-FolderSizeMB "$env:SystemDrive\inetpub\logs\LogFiles"
    Get-ChildItem "$env:SystemDrive\inetpub\logs\LogFiles" -Recurse -File -ErrorAction SilentlyContinue |
        Where-Object { $_.LastWriteTime -lt $cutoff } |
        ForEach-Object { try { Remove-Item $_.FullName -Force -ErrorAction Stop } catch {} }
    $after = Get-FolderSizeMB "$env:SystemDrive\inetpub\logs\LogFiles"
    $f = [math]::Max(0, $before - $after)
    Write-Host ("  IIS-Logs: -{0} MB" -f $f)
    Add-Step "IISLogs" $f
}
#endregion

#region --- 10. Papierkorb (alle Laufwerke) -----------------------------------
Write-Section "10. Papierkorb"
$f = 0
try {
    # Groesse vorher ueber Shell ermitteln ist umstaendlich - wir nutzen Clear-RecycleBin
    Clear-RecycleBin -Force -ErrorAction Stop
    Write-Host "  Papierkorb geleert."
} catch {
    Write-Host "  Papierkorb-Clear fehlgeschlagen: $($_.Exception.Message)"
    $script:Stats.Errors++
}
Add-Step "RecycleBin" $f "geleert (Groessenmessung n/a)"
#endregion

#region --- 11. DISM Component Cleanup ----------------------------------------
if (-not $SkipDISM) {
    Write-Section "11. DISM /StartComponentCleanup /ResetBase  (langlaufend, irreversibel)"
    try {
        $winsxsBefore = Get-FolderSizeMB "$env:windir\WinSxS"
        & dism.exe /Online /Cleanup-Image /StartComponentCleanup /ResetBase | Out-Host
        $winsxsAfter = Get-FolderSizeMB "$env:windir\WinSxS"
        $f = [math]::Max(0, $winsxsBefore - $winsxsAfter)
        Add-Step "DISM" $f
    } catch {
        Write-Host "  DISM-Fehler: $($_.Exception.Message)"
        $script:Stats.Errors++
        Add-Step "DISM" 0 "Fehler"
    }
} else {
    Add-Step "DISM" 0 "uebersprungen"
}
#endregion

#region --- 12. cleanmgr /sagerun:1 -------------------------------------------
if (-not $SkipCleanMgr) {
    Write-Section "12. cleanmgr /sagerun:1"
    # Standard-Profil 1 anlegen, falls nicht vorhanden
    $regBase = 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\VolumeCaches'
    if (Test-Path $regBase) {
        Get-ChildItem $regBase | ForEach-Object {
            try { New-ItemProperty -Path $_.PSPath -Name 'StateFlags0001' -Value 2 -PropertyType DWord -Force -ErrorAction SilentlyContinue | Out-Null } catch {}
        }
    }
    try {
        Start-Process -FilePath "$env:windir\System32\cleanmgr.exe" -ArgumentList '/sagerun:1' -Wait -WindowStyle Hidden
        Write-Host "  cleanmgr beendet."
        Add-Step "CleanMgr" 0 "ausgefuehrt"
    } catch {
        Write-Host "  cleanmgr-Fehler: $($_.Exception.Message)"
        $script:Stats.Errors++
        Add-Step "CleanMgr" 0 "Fehler"
    }
} else {
    Add-Step "CleanMgr" 0 "uebersprungen"
}
#endregion

#region --- 13. Eigene alte Logs aufraeumen (>30 Tage) ------------------------
Write-Section "13. Wartungs-Logs > 30 Tage rotieren"
Get-ChildItem $LogRoot -File -ErrorAction SilentlyContinue |
    Where-Object { $_.LastWriteTime -lt (Get-Date).AddDays(-30) } |
    ForEach-Object { try { Remove-Item $_.FullName -Force -ErrorAction Stop } catch {} }
#endregion

#region --- Abschluss ---------------------------------------------------------
$script:Stats.EndedAt = (Get-Date).ToString('s')
Write-Section "Zusammenfassung"
$script:Stats.Steps | Format-Table Step, FreedMB, Note -AutoSize | Out-Host
Write-Host ("Gesamt freigegeben: {0} MB ({1} GB)" -f $script:Stats.TotalFreedMB, [math]::Round($script:Stats.TotalFreedMB/1024,2))
Write-Host ("Fehler: {0}" -f $script:Stats.Errors)

$script:Stats | ConvertTo-Json -Depth 5 | Set-Content -Path $statsFile -Encoding UTF8
Stop-Transcript | Out-Null

# Stats-Objekt fuer Remoting zurueckgeben
[pscustomobject]$script:Stats
#endregion