[CmdletBinding()]
param(
    [Parameter(Mandatory = $true, Position = 0)]
    [ValidateSet('Prepare', 'Status', 'Run', 'Collect', 'Stop', 'Reset')]
    [string] $Action,
    [Parameter(Mandatory = $false)]
    [ValidatePattern('^[a-z0-9][a-z0-9-]{0,63}$')]
    [string] $RunId = '',
    [string] $VmName = $(if ($env:RVBOX_WINDOWS_VM) { $env:RVBOX_WINDOWS_VM } elseif ($env:RVBOX_TEST_VBOX_VM) { $env:RVBOX_TEST_VBOX_VM } else { 'rvbox-win10-test' }),
    [string] $Snapshot = $(if ($env:RVBOX_WINDOWS_BASELINE_SNAPSHOT) { $env:RVBOX_WINDOWS_BASELINE_SNAPSHOT } elseif ($env:RVBOX_TEST_VBOX_SNAPSHOT) { $env:RVBOX_TEST_VBOX_SNAPSHOT } else { 'baseline-disk-first' })
)

$ErrorActionPreference = 'Stop'
$VBoxManage = if ($env:VBOXMANAGE) { $env:VBOXMANAGE } else { 'VBoxManage' }
$GuestUser = if ($env:RVBOX_WINDOWS_GUEST_USER) { $env:RVBOX_WINDOWS_GUEST_USER } else { $env:RVBOX_TEST_GUEST_USER }
$GuestPasswordFile = if ($env:RVBOX_WINDOWS_GUEST_PASSWORD_FILE) {
    $env:RVBOX_WINDOWS_GUEST_PASSWORD_FILE
} else {
    $env:RVBOX_TEST_GUEST_PASSWORD_FILE
}
$LeaseRoot = if ($env:RVBOX_WINDOWS_LEASE_DIR) { $env:RVBOX_WINDOWS_LEASE_DIR } else { Join-Path $PSScriptRoot '..\..\.test-runs\windows' }

function Invoke-VBox([string[]] $Arguments) {
    $output = & $VBoxManage @Arguments 2>&1
    if ($LASTEXITCODE -ne 0) {
        throw "VBoxManage failed ($LASTEXITCODE): $($output -join ' ')"
    }
    return $output
}

function Require-RunId {
    if ([string]::IsNullOrWhiteSpace($RunId)) { throw "$Action requires -RunId" }
}

function Acquire-Lease {
    New-Item -ItemType Directory -Force -Path $LeaseRoot | Out-Null
    $path = Join-Path $LeaseRoot 'lease.lock'
    try {
        $script:Lease = [System.IO.File]::Open($path, [System.IO.FileMode]::OpenOrCreate, [System.IO.FileAccess]::ReadWrite, [System.IO.FileShare]::None)
        $bytes = [Text.Encoding]::UTF8.GetBytes("$VmName`n$RunId`n$([DateTime]::UtcNow.ToString('o'))`n")
        $Lease.SetLength(0); $Lease.Write($bytes, 0, $bytes.Length); $Lease.Flush($true)
    } catch {
        throw "Windows test VM is already leased: $path"
    }
}

function Release-Lease {
    if ($script:Lease) { $script:Lease.Dispose(); $script:Lease = $null }
}

function Guest-Args([string[]] $Arguments) {
    if ([string]::IsNullOrWhiteSpace($GuestUser) -or [string]::IsNullOrWhiteSpace($GuestPasswordFile)) {
        throw 'Set the guest user and password-file environment variables in the host environment; secrets are never read from repository files or printed.'
    }
    if (-not (Test-Path -LiteralPath $GuestPasswordFile -PathType Leaf)) {
        throw "Guest password file does not exist: $GuestPasswordFile"
    }
    return @('guestcontrol', $VmName, '--username', $GuestUser, '--passwordfile', $GuestPasswordFile) + $Arguments
}

function Wait-PowerOff {
    for ($attempt = 0; $attempt -lt 60; $attempt++) {
        $current = (Invoke-VBox @('showvminfo', $VmName, '--machinereadable') | Where-Object { $_ -like 'VMState=*' }) -replace '^VMState="?([^"\r\n]+)"?$', '$1'
        if ($current -eq 'poweroff') { return }
        Start-Sleep -Seconds 1
    }
    throw "VM did not power off within the bounded stop deadline: $VmName"
}

function Wait-GuestReady {
    for ($attempt = 0; $attempt -lt 60; $attempt++) {
        $properties = Invoke-VBox @('guestproperty', 'enumerate', $VmName)
        if (($properties -match '/GuestAdd/Version') -and ($properties -match '/GuestInfo/OS/Release')) {
            return
        }
        Start-Sleep -Seconds 1
    }
    throw "Guest Additions did not become ready within the bounded boot deadline: $VmName"
}

try {
    if ($Action -eq 'Status') {
        Invoke-VBox @('showvminfo', $VmName, '--machinereadable') | Where-Object { $_ -match '^(VMState|name|SnapshotName)=' }
        exit 0
    }
    Require-RunId
    Acquire-Lease
    try {
        $state = (Invoke-VBox @('showvminfo', $VmName, '--machinereadable') | Where-Object { $_ -like 'VMState=*' }) -replace '^VMState="?([^"\r\n]+)"?$', '$1'
        switch ($Action) {
            'Prepare' {
                if ($state -eq 'running') { Wait-GuestReady }
                else {
                    Invoke-VBox @('startvm', $VmName, '--type', 'headless') | Out-Null
                    Wait-GuestReady
                }
                Invoke-VBox (Guest-Args @('run', '--exe', 'C:\Windows\System32\whoami.exe', '--wait-stdout', '--wait-stderr', '--unquoted-args', '--', '/groups')) | Out-Null
                Invoke-VBox (Guest-Args @('run', '--exe', 'C:\Windows\System32\query.exe', '--wait-stdout', '--wait-stderr', '--unquoted-args', '--', 'user')) | Out-Null
                Write-Output "prepared VM=$VmName run=$RunId"
            }
            'Run' {
                $guestBinary = if ($env:RVBOX_WINDOWS_GUEST_BINARY) { $env:RVBOX_WINDOWS_GUEST_BINARY } else { 'C:\ProgramData\RVBox\test\rvbox.exe' }
                Invoke-VBox (Guest-Args @('run', '--exe', $guestBinary, '--wait-stdout', '--wait-stderr', '--unquoted-args', '--', '--check-config', '--config', 'C:\ProgramData\RVBox\client.toml')) | Out-Null
                Write-Output "ran native Windows smoke run=$RunId"
            }
            'Collect' {
                $destination = Join-Path $LeaseRoot $RunId
                New-Item -ItemType Directory -Force -Path $destination | Out-Null
                $guestArtifacts = if ($env:RVBOX_WINDOWS_GUEST_ARTIFACTS) { $env:RVBOX_WINDOWS_GUEST_ARTIFACTS } else { 'C:\ProgramData\RVBox\test-artifacts' }
                Invoke-VBox (Guest-Args @('copyfrom', $guestArtifacts, $destination, '--recursive')) | Out-Null
                Write-Output "collected native artifacts under $destination"
            }
            'Stop' {
                if ($state -eq 'running') { Invoke-VBox @('controlvm', $VmName, 'acpipowerbutton') | Out-Null; Wait-PowerOff }
                Write-Output "requested graceful stop VM=$VmName"
            }
            'Reset' {
                if ($state -eq 'running') { Invoke-VBox @('controlvm', $VmName, 'acpipowerbutton') | Out-Null; Wait-PowerOff }
                Invoke-VBox @('snapshot', $VmName, 'restore', $Snapshot) | Out-Null
                Write-Output "restored baseline snapshot=$Snapshot VM=$VmName run=$RunId"
            }
        }
    } finally {
        Release-Lease
    }
} catch {
    Release-Lease
    Write-Error $_
    exit 1
}