#Requires -Version 5.1
<#
.SYNOPSIS
    Installiert/Deinstalliert Kontextmenü-Einträge für Datei-/Ordnerfreigaben
.DESCRIPTION
    Erstellt Kontextmenü-Einträge "Freigeben für Mitarbeiter" und "Freigabe entfernen"
.PARAMETER Install
    Installiert die Kontextmenü-Einträge
.PARAMETER Uninstall
    Entfernt die Kontextmenü-Einträge (Freigaben bleiben erhalten)
.PARAMETER AllUsers
    Installation für alle Benutzer (erfordert Admin-Rechte)
.PARAMETER CurrentUser
    Installation nur für aktuellen Benutzer
.PARAMETER LinkBasePath
    Stammverzeichnis für Benutzer-Verknüpfungsordner
#>

param(
    [switch]$Install,
    [switch]$Uninstall,
    [switch]$AllUsers,
    [switch]$CurrentUser,
    [string]$LinkBasePath
)

$ErrorActionPreference = "Stop"

function Test-Administrator {
    $currentUser = [Security.Principal.WindowsIdentity]::GetCurrent()
    $principal = New-Object Security.Principal.WindowsPrincipal($currentUser)
    return $principal.IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)
}

function Get-ScriptDirectory {
    return $PSScriptRoot
}

function Show-Menu {
    Clear-Host
    Write-Host "========================================" -ForegroundColor Cyan
    Write-Host "  Freigabe-Kontextmen$([char]0x00FC) Installation" -ForegroundColor Cyan
    Write-Host "========================================" -ForegroundColor Cyan
    Write-Host ""
    Write-Host "[1] Installieren f$([char]0x00FC)r aktuellen Benutzer"
    Write-Host "[2] Installieren f$([char]0x00FC)r alle Benutzer (Admin erforderlich)"
    Write-Host "[3] Deinstallieren f$([char]0x00FC)r aktuellen Benutzer"
    Write-Host "[4] Deinstallieren f$([char]0x00FC)r alle Benutzer (Admin erforderlich)"
    Write-Host "[Q] Beenden"
    Write-Host ""
}

function Get-LinkBasePath {
    Add-Type -AssemblyName System.Windows.Forms
    
    $form = New-Object System.Windows.Forms.Form
    $form.Text = "Stammverzeichnis f$([char]0x00FC)r Verkn$([char]0x00FC)pfungen"
    $form.Size = New-Object System.Drawing.Size(500, 180)
    $form.StartPosition = "CenterScreen"
    $form.FormBorderStyle = "FixedDialog"
    $form.MaximizeBox = $false
    
    $label = New-Object System.Windows.Forms.Label
    $label.Text = "Stammverzeichnis f$([char]0x00FC)r Benutzer-Verkn$([char]0x00FC)pfungsordner:"
    $label.Location = New-Object System.Drawing.Point(10, 20)
    $label.Size = New-Object System.Drawing.Size(460, 20)
    $form.Controls.Add($label)
    
    $textBox = New-Object System.Windows.Forms.TextBox
    $textBox.Location = New-Object System.Drawing.Point(10, 45)
    $textBox.Size = New-Object System.Drawing.Size(380, 20)
    $textBox.Text = "C:\Freigaben\Benutzer"
    $form.Controls.Add($textBox)
    
    $browseBtn = New-Object System.Windows.Forms.Button
    $browseBtn.Text = "..."
    $browseBtn.Location = New-Object System.Drawing.Point(395, 43)
    $browseBtn.Size = New-Object System.Drawing.Size(75, 25)
    $browseBtn.Add_Click({
        $folderBrowser = New-Object System.Windows.Forms.FolderBrowserDialog
        $folderBrowser.Description = "Stammverzeichnis ausw$([char]0x00E4)hlen"
        if ($folderBrowser.ShowDialog() -eq "OK") {
            $textBox.Text = $folderBrowser.SelectedPath
        }
    })
    $form.Controls.Add($browseBtn)
    
    $okBtn = New-Object System.Windows.Forms.Button
    $okBtn.Text = "OK"
    $okBtn.Location = New-Object System.Drawing.Point(310, 100)
    $okBtn.Size = New-Object System.Drawing.Size(75, 25)
    $okBtn.DialogResult = [System.Windows.Forms.DialogResult]::OK
    $form.AcceptButton = $okBtn
    $form.Controls.Add($okBtn)
    
    $cancelBtn = New-Object System.Windows.Forms.Button
    $cancelBtn.Text = "Abbrechen"
    $cancelBtn.Location = New-Object System.Drawing.Point(395, 100)
    $cancelBtn.Size = New-Object System.Drawing.Size(75, 25)
    $cancelBtn.DialogResult = [System.Windows.Forms.DialogResult]::Cancel
    $form.CancelButton = $cancelBtn
    $form.Controls.Add($cancelBtn)
    
    $result = $form.ShowDialog()
    
    if ($result -eq [System.Windows.Forms.DialogResult]::OK) {
        return $textBox.Text
    }
    return $null
}

function Install-ContextMenu {
    param(
        [bool]$ForAllUsers,
        [string]$BasePath
    )
    
    $scriptDir = Get-ScriptDirectory
    $freigabeScript = Join-Path $scriptDir "Freigabe-Hinzufuegen.ps1"
    $entfernenScript = Join-Path $scriptDir "Freigabe-Entfernen.ps1"
    
    if ($ForAllUsers) {
        if (-not (Test-Administrator)) {
            throw "Admin-Rechte erforderlich f$([char]0x00FC)r Installation f$([char]0x00FC)r alle Benutzer!"
        }
        $regBase = "HKLM:\SOFTWARE\Classes"
        $configPath = "$env:ProgramData\FreigabeKontextmenue"
    } else {
        $regBase = "HKCU:\SOFTWARE\Classes"
        $configPath = "$env:APPDATA\FreigabeKontextmenue"
    }
    
    if (-not (Test-Path $configPath)) {
        New-Item -Path $configPath -ItemType Directory -Force | Out-Null
    }
    
    $config = @{
        LinkBasePath = $BasePath
        InstalledFor = if ($ForAllUsers) { "AllUsers" } else { "CurrentUser" }
        InstallDate = (Get-Date).ToString("yyyy-MM-dd HH:mm:ss")
        ScriptDirectory = $scriptDir
    }
    $config | ConvertTo-Json | Set-Content -Path (Join-Path $configPath "config.json") -Encoding UTF8
    
    $shellExTypes = @(
        "*\shell",
        "Directory\shell",
        "Directory\Background\shell"
    )
    
    foreach ($shellType in $shellExTypes) {
        $freigabeKey = "$regBase\$shellType\FreigabeFuerMitarbeiter"
        $entfernenKey = "$regBase\$shellType\FreigabeEntfernen"
        
        if (-not (Test-Path $freigabeKey)) {
            New-Item -Path $freigabeKey -Force | Out-Null
        }
        Set-ItemProperty -Path $freigabeKey -Name "(Default)" -Value "Freigeben f$([char]0x00FC)r Mitarbeiter"
        Set-ItemProperty -Path $freigabeKey -Name "Icon" -Value "imageres.dll,232"
        
        $freigabeCmd = "$freigabeKey\command"
        if (-not (Test-Path $freigabeCmd)) {
            New-Item -Path $freigabeCmd -Force | Out-Null
        }
        
        if ($shellType -eq "Directory\Background\shell") {
            Set-ItemProperty -Path $freigabeCmd -Name "(Default)" -Value "powershell.exe -ExecutionPolicy Bypass -WindowStyle Hidden -File `"$freigabeScript`" -Path `"%V`""
        } else {
            Set-ItemProperty -Path $freigabeCmd -Name "(Default)" -Value "powershell.exe -ExecutionPolicy Bypass -WindowStyle Hidden -File `"$freigabeScript`" -Path `"%1`""
        }
        
        if (-not (Test-Path $entfernenKey)) {
            New-Item -Path $entfernenKey -Force | Out-Null
        }
        Set-ItemProperty -Path $entfernenKey -Name "(Default)" -Value "Freigabe f$([char]0x00FC)r Mitarbeiter entfernen"
        Set-ItemProperty -Path $entfernenKey -Name "Icon" -Value "imageres.dll,229"
        
        $entfernenCmd = "$entfernenKey\command"
        if (-not (Test-Path $entfernenCmd)) {
            New-Item -Path $entfernenCmd -Force | Out-Null
        }
        
        if ($shellType -eq "Directory\Background\shell") {
            Set-ItemProperty -Path $entfernenCmd -Name "(Default)" -Value "powershell.exe -ExecutionPolicy Bypass -WindowStyle Hidden -File `"$entfernenScript`" -Path `"%V`""
        } else {
            Set-ItemProperty -Path $entfernenCmd -Name "(Default)" -Value "powershell.exe -ExecutionPolicy Bypass -WindowStyle Hidden -File `"$entfernenScript`" -Path `"%1`""
        }
    }
    
    if (-not (Test-Path $BasePath)) {
        New-Item -Path $BasePath -ItemType Directory -Force | Out-Null
        Write-Host "Stammverzeichnis erstellt: $BasePath" -ForegroundColor Green
    }
    
    Write-Host "Installation erfolgreich abgeschlossen!" -ForegroundColor Green
}

function Uninstall-ContextMenu {
    param(
        [bool]$ForAllUsers
    )
    
    if ($ForAllUsers) {
        if (-not (Test-Administrator)) {
            throw "Admin-Rechte erforderlich f$([char]0x00FC)r Deinstallation f$([char]0x00FC)r alle Benutzer!"
        }
        $regBase = "HKLM:\SOFTWARE\Classes"
        $configPath = "$env:ProgramData\FreigabeKontextmenue"
    } else {
        $regBase = "HKCU:\SOFTWARE\Classes"
        $configPath = "$env:APPDATA\FreigabeKontextmenue"
    }
    
    $shellExTypes = @(
        "*\shell",
        "Directory\shell",
        "Directory\Background\shell"
    )
    
    foreach ($shellType in $shellExTypes) {
        $freigabeKey = "$regBase\$shellType\FreigabeFuerMitarbeiter"
        $entfernenKey = "$regBase\$shellType\FreigabeEntfernen"
        
        if (Test-Path $freigabeKey) {
            Remove-Item -Path $freigabeKey -Recurse -Force
        }
        if (Test-Path $entfernenKey) {
            Remove-Item -Path $entfernenKey -Recurse -Force
        }
    }
    
    if (Test-Path $configPath) {
        Remove-Item -Path $configPath -Recurse -Force
    }
    
    Write-Host "Deinstallation erfolgreich!" -ForegroundColor Green
    Write-Host "Hinweis: Bestehende Freigaben und Verkn$([char]0x00FC)pfungen wurden NICHT entfernt." -ForegroundColor Yellow
}

if ($Install -or $Uninstall) {
    if ($Install) {
        $forAll = $AllUsers -and -not $CurrentUser
        if (-not $LinkBasePath) {
            $LinkBasePath = Get-LinkBasePath
            if (-not $LinkBasePath) {
                Write-Host "Installation abgebrochen." -ForegroundColor Yellow
                exit 1
            }
        }
        Install-ContextMenu -ForAllUsers $forAll -BasePath $LinkBasePath
    }
    if ($Uninstall) {
        $forAll = $AllUsers -and -not $CurrentUser
        Uninstall-ContextMenu -ForAllUsers $forAll
    }
} else {
    do {
        Show-Menu
        $choice = Read-Host "Auswahl"
        
        switch ($choice.ToUpper()) {
            "1" {
                $basePath = Get-LinkBasePath
                if ($basePath) {
                    Install-ContextMenu -ForAllUsers $false -BasePath $basePath
                }
                pause
            }
            "2" {
                if (-not (Test-Administrator)) {
                    Write-Host "Bitte als Administrator ausf$([char]0x00FC)hren!" -ForegroundColor Red
                } else {
                    $basePath = Get-LinkBasePath
                    if ($basePath) {
                        Install-ContextMenu -ForAllUsers $true -BasePath $basePath
                    }
                }
                pause
            }
            "3" {
                Uninstall-ContextMenu -ForAllUsers $false
                pause
            }
            "4" {
                if (-not (Test-Administrator)) {
                    Write-Host "Bitte als Administrator ausf$([char]0x00FC)hren!" -ForegroundColor Red
                } else {
                    Uninstall-ContextMenu -ForAllUsers $true
                }
                pause
            }
        }
    } while ($choice.ToUpper() -ne "Q")
}