# Prompt-MachineNumber.ps1 - User-context GUI script for the two-task
# machine number flow. Triggered AtLogOn for any BUILTIN\Users member.
#
# Flow:
#   1. Read current UDC + eDNC values (read-only - no privileges needed).
#   2. If neither is 9999, unregister self and exit (this PC is set up).
#   3. Show InputBox for new machine number.
#   4. Write number to C:\Logs\SFLD\machine-number-request.txt.
#   5. Trigger the SYSTEM-context Apply-MachineNumber task via
#      schtasks /run. SYSTEM has full HKLM + ProgramData access so the
#      actual write happens with proper privileges - the prompted user
#      never needs HKLM write rights (security improvement over the old
#      02-MachineNumberACLs.ps1 ACL-grant hack).
#   6. Poll for C:\Logs\SFLD\machine-number-result.json (30s timeout).
#   7. Show result MessageBox. Unregister self on success.
#
# Why this script doesn't do the writes itself: GUI is required (InputBox),
# but GUI requires user-context (SYSTEM can't render to user desktop on
# modern Windows). The user-context dialog gathers input; the SYSTEM task
# does privileged writes.

# --- Transcript ---
$logDir = 'C:\Logs\SFLD'
if (-not (Test-Path -LiteralPath $logDir)) {
    try { New-Item -ItemType Directory -Path $logDir -Force | Out-Null } catch { $logDir = $env:TEMP }
}
$transcript = Join-Path $logDir 'Prompt-MachineNumber.log'
try { Start-Transcript -Path $transcript -Append -Force | Out-Null } catch {}
Write-Host "Prompt-MachineNumber.ps1 starting $(Get-Date -Format 'yyyy-MM-dd HH:mm:ss')"
Write-Host "Running as: $([System.Security.Principal.WindowsIdentity]::GetCurrent().Name)"

. "$PSScriptRoot\lib\Get-PCProfile.ps1"
. "$PSScriptRoot\lib\Update-MachineNumber.ps1"

Add-Type -AssemblyName Microsoft.VisualBasic
Add-Type -AssemblyName System.Windows.Forms

$taskName     = 'Prompt Machine Number'
$applyTaskName = 'Apply Machine Number'
$requestFile  = Join-Path $logDir 'machine-number-request.txt'
$resultFile   = Join-Path $logDir 'machine-number-result.json'
$site         = if ($siteConfig) { $siteConfig.siteName } else { 'West Jefferson' }

# --- Read current values (read-only, no perms needed) ---
$currentMN   = Get-CurrentMachineNumber
$currentUdc  = $currentMN.Udc
$currentEdnc = $currentMN.Ednc
Write-Host "UDC  machine number: $(if ($currentUdc) { $currentUdc } else { '(not found)' })"
Write-Host "eDNC machine number: $(if ($currentEdnc) { $currentEdnc } else { '(not found)' })"

if ($currentUdc -ne '9999' -and $currentEdnc -ne '9999') {
    Write-Host "Machine number is set (not 9999). Unregistering Prompt task and exiting."
    try { Unregister-ScheduledTask -TaskName $taskName -Confirm:$false -ErrorAction SilentlyContinue } catch {}
    try { Stop-Transcript | Out-Null } catch {}
    exit 0
}

Write-Host "Placeholder 9999 detected - showing prompt."

# --- Show prompt ---
$promptLines = @()
$promptLines += "The machine number on this PC is still set to the"
$promptLines += "placeholder value (9999). Please enter the correct"
$promptLines += "machine number for this workstation."
$promptLines += ""
if ($currentUdc)  { $promptLines += "Current UDC:  $currentUdc" }
if ($currentEdnc) { $promptLines += "Current eDNC: $currentEdnc" }
$promptLines += ""
$promptLines += "Enter the new Machine Number:"
$prompt = $promptLines -join "`n"
$new = [Microsoft.VisualBasic.Interaction]::InputBox($prompt, "Set Machine Number", "")

if ([string]::IsNullOrWhiteSpace($new)) {
    Write-Host "User cancelled. Will prompt again next logon."
    try { Stop-Transcript | Out-Null } catch {}
    exit 0
}
$new = $new.Trim()

if ($new -notmatch '^\d+$') {
    Write-Host "Invalid input: '$new' (not digits only). Showing error and re-prompting next logon."
    [System.Windows.Forms.MessageBox]::Show(
        "Machine number must be digits only.`n`nYou entered: '$new'`n`nThe prompt will appear again at next logon.",
        "Invalid Machine Number",
        [System.Windows.Forms.MessageBoxButtons]::OK,
        [System.Windows.Forms.MessageBoxIcon]::Error
    ) | Out-Null
    try { Stop-Transcript | Out-Null } catch {}
    exit 0
}

# --- Hand off to SYSTEM task ---
# Clean any stale request / result files first so we read fresh ones.
Remove-Item -LiteralPath $requestFile, $resultFile -Force -ErrorAction SilentlyContinue

try {
    Set-Content -LiteralPath $requestFile -Value $new -Encoding ascii -Force -ErrorAction Stop
} catch {
    [System.Windows.Forms.MessageBox]::Show(
        "Could not write request file at $requestFile`n`n$_`n`nThe prompt will appear again at next logon.",
        "Machine Number Request Failed",
        [System.Windows.Forms.MessageBoxButtons]::OK,
        [System.Windows.Forms.MessageBoxIcon]::Error
    ) | Out-Null
    try { Stop-Transcript | Out-Null } catch {}
    exit 1
}

Write-Host "Wrote $requestFile with '$new'. Triggering SYSTEM apply task..."
& schtasks.exe /run /tn $applyTaskName 2>&1 | ForEach-Object { Write-Host "  schtasks: $_" }

# --- Wait for result ---
$deadline = (Get-Date).AddSeconds(60)
$result = $null
while ((Get-Date) -lt $deadline) {
    if (Test-Path -LiteralPath $resultFile) {
        try {
            $result = Get-Content -LiteralPath $resultFile -Raw -ErrorAction Stop | ConvertFrom-Json
            break
        } catch { Start-Sleep -Milliseconds 200 }
    }
    Start-Sleep -Milliseconds 500
}

# Make the result MessageBox topmost so it shows above the FormTracePak /
# DNC windows and isn't missed.
$tmpForm = New-Object System.Windows.Forms.Form
$tmpForm.TopMost = $true
$tmpForm.WindowState = 'Minimized'
$tmpForm.ShowInTaskbar = $false
$tmpForm.Opacity = 0
$tmpForm.Show()

if (-not $result) {
    Write-Host "Timed out waiting for SYSTEM apply task to produce result file ($resultFile)."
    [System.Windows.Forms.MessageBox]::Show(
        $tmpForm,
        "Timed out waiting for the SYSTEM update task to complete.`n`nCheck:`n  C:\Logs\SFLD\Apply-MachineNumber.log`n  C:\Logs\SFLD\Prompt-MachineNumber.log`n`nThe prompt will appear again at next logon.",
        "Machine Number Update Timed Out",
        [System.Windows.Forms.MessageBoxButtons]::OK,
        [System.Windows.Forms.MessageBoxIcon]::Warning
    ) | Out-Null
    $tmpForm.Close()
    try { Stop-Transcript | Out-Null } catch {}
    exit 1
}

# Build summary from result JSON
$lines = @()
$lines += "Requested: $($result.Requested)"
$lines += ""
if ($result.UdcUpdated)  { $lines += "UDC updated to $($result.Requested)" } else { $lines += "UDC: not updated (UDC may not be installed)" }
if ($result.EdncUpdated) { $lines += "eDNC updated to $($result.Requested)" } else { $lines += "eDNC: not updated" }
if ($result.UdcSettingsRestored) { $lines += "UDC settings restored from SFLD" }
if ($result.UdcRestored)         { $lines += "UDC live data restored from SFLD" }
if ($result.MachineNumberTxtUpdated) { $lines += "machine-number.txt updated" }
if ($result.MTConnectUpdated -and $result.MTConnectUpdated.Count -gt 0) {
    $lines += ""
    $lines += "MTConnect Devices.xml updates:"
    $result.MTConnectUpdated | ForEach-Object { $lines += "  - $_" }
}
if ($result.Errors -and $result.Errors.Count -gt 0) {
    $lines += ""
    $lines += "FAILURES:"
    $result.Errors | ForEach-Object { $lines += "  - $_" }
}
$lines += ""
$lines += "Status: $($result.Status)"
$lines += "Logs: C:\Logs\SFLD\Apply-MachineNumber.log"
$lines += "      C:\Logs\SFLD\Prompt-MachineNumber.log"
$lines += ""
$lines += "To apply eDNC changes, restart any running DncMain.exe."
$summary = $lines -join "`n"

$icon = if ($result.Status -eq 'OK') { [System.Windows.Forms.MessageBoxIcon]::Information } else { [System.Windows.Forms.MessageBoxIcon]::Warning }
[System.Windows.Forms.MessageBox]::Show(
    $tmpForm,
    $summary,
    "Machine Number Update Result",
    [System.Windows.Forms.MessageBoxButtons]::OK,
    $icon
) | Out-Null
$tmpForm.Close()

# Clean up result file for the next round.
Remove-Item -LiteralPath $resultFile -Force -ErrorAction SilentlyContinue

# Only unregister the Prompt task on full success (no errors AND eDNC
# updated to the requested value). If anything failed, leave it registered
# for next logon retry.
if ($result.Status -eq 'OK' -and $result.EdncUpdated) {
    Write-Host "All updates succeeded. Unregistering Prompt task."
    try { Unregister-ScheduledTask -TaskName $taskName -Confirm:$false -ErrorAction SilentlyContinue } catch {}
} else {
    Write-Host "Some updates failed or skipped. Prompt task stays registered for next logon retry."
}

Write-Host "Prompt-MachineNumber.ps1 finished $(Get-Date -Format 'yyyy-MM-dd HH:mm:ss')"
try { Stop-Transcript | Out-Null } catch {}
exit 0