<#
.SYNOPSIS
  Exports the player's cybernetic arm from the user's .blend to SourceArt\Arm (one FBX per segment + manifest) and
  regenerates Source\TheDescent\Player\Arm\ArmLayout.inl. Headless Blender; the .blend is never saved.

.EXAMPLE
  powershell -NoProfile -ExecutionPolicy Bypass -File Tools\export_arm.ps1
  Exit code 0 = PASS, 1 = FAIL.
#>
[CmdletBinding()]
param(
    [string]$Blend = 'D:\HADAL - The Descent\models\robotic-arm\robotic-arm.blend'
)
$ErrorActionPreference = 'Stop'
$ProjectRoot = Split-Path -Parent $PSScriptRoot
$Blender = 'E:\Steam\steamapps\common\Blender\blender.exe'
$Script  = Join-Path $PSScriptRoot 'blender\export_arm.py'
$LogFile = Join-Path $ProjectRoot 'Saved\Logs\export_arm_last.log'

if (-not (Test-Path $Blender)) { Write-Host "EXPORT FAIL: Blender not found at $Blender"; exit 1 }
if (-not (Test-Path $Blend))   { Write-Host "EXPORT FAIL: $Blend not found"; exit 1 }
New-Item -ItemType Directory -Force -Path (Split-Path $LogFile) | Out-Null

$before = Get-Item $Blend
$sw = [System.Diagnostics.Stopwatch]::StartNew()
$blArgs = @('-b', ('"' + $Blend + '"'), '--python-exit-code', '1', '--python', ('"' + $Script + '"'), '--')

# Blender prints progress to stdout; keep all of it in the log file. cmd /c so stderr lines stay plain text.
cmd.exe /c ('"' + $Blender + '" ' + ($blArgs -join ' ') + ' > "' + $LogFile + '" 2>&1')
$exit = $LASTEXITCODE
$sw.Stop()

$lines = Get-Content $LogFile
if ($VerbosePreference -eq 'Continue') { $lines | ForEach-Object { Write-Host $_ } }
else { $lines | Where-Object { $_ -match '^\[export_arm\]' } | ForEach-Object { Write-Host $_ } }

$after = Get-Item $Blend
if ($before.Length -ne $after.Length -or $before.LastWriteTimeUtc -ne $after.LastWriteTimeUtc) {
    Write-Host "EXPORT FAIL: the source .blend changed on disk. This must never happen."
    exit 1
}
$secs = [math]::Round($sw.Elapsed.TotalSeconds, 1)
if ($exit -eq 0) { Write-Host ("EXPORT PASS  {0}s  -> SourceArt\Arm" -f $secs); exit 0 }
Write-Host ("EXPORT FAIL  exit={0}  {1}s  log={2}" -f $exit, $secs, $LogFile)
exit 1