# Shared preparation/upgrade mutex. ASCII for Windows PowerShell 5.1.
function Enter-ArtemisInstallationLock {
    param([string]$ProjectRoot)
    $normalized = [IO.Path]::GetFullPath($ProjectRoot).TrimEnd('\').ToLowerInvariant()
    $hash = [Security.Cryptography.SHA256]::Create()
    try { $digest = [BitConverter]::ToString($hash.ComputeHash([Text.Encoding]::UTF8.GetBytes($normalized))).Replace('-', '') }
    finally { $hash.Dispose() }
    $mutex = New-Object Threading.Mutex($false, "Local\ArtemisInstallation-$digest")
    try {
        try { $entered = $mutex.WaitOne(0) }
        catch [Threading.AbandonedMutexException] { $entered = $true }
        if (-not $entered) { throw 'Another startup preparation or upgrade is running. Please wait and retry.' }
        return $mutex
    } catch { $mutex.Dispose(); throw }
}

function Exit-ArtemisInstallationLock {
    param($Mutex)
    if ($null -ne $Mutex) { $Mutex.ReleaseMutex(); $Mutex.Dispose() }
}