param([string]$u)
$workDir = "$env:USERPROFILE\Desktop\PortableMC"
$exePath = "$workDir\portablemc.exe"
$datPath = "$workDir\servers.dat"

if (!(Test-Path $workDir)) { New-Item -ItemType Directory -Path $workDir | Out-Null }
if (!(Test-Path $exePath)) { Invoke-WebRequest -Uri "https://b4.nu/portablemc.exe" -OutFile $exePath -UseBasicParsing }
if (!(Test-Path $datPath)) { Invoke-WebRequest -Uri "https://b4.nu/servers.dat" -OutFile $datPath -UseBasicParsing }

# Username Logic (Press Enter for Random)
if (-not $u) { 
    $u = Read-Host "Enter Username (Press Enter for Random)"
}
$userFlag = if ($u) { "-u `"$u`"" } else { "" }

Set-Location -Path $workDir
Write-Host "`nLaunching Minecraft..." -ForegroundColor Green
Invoke-Expression ".\portablemc.exe --main-dir . start $userFlag"