<#
.SYNOPSIS
  Restore local-only WIP (stashes + untracked diffs) that was rescued into the
  recovery bundle's at-risk-work\ folder. Run AFTER the repos + submodules are cloned.

.DESCRIPTION
  guru-rmm  : each stashN-*.patch is applied to the working tree and then re-stashed,
              faithfully recreating the original `git stash` entries. Patches are
              processed highest-N-first so stash0 ends up on top (stash@{0}), matching
              the original LIFO order. The working tree is left CLEAN (changes live in
              the stash, exactly as before).
  guru-connect : tmp-spec018.diff was an UNTRACKED working file, so it is copied back
              into the repo as-is (not applied). Apply it yourself if/when you want it.

  Non-destructive and re-runnable. If a patch won't apply cleanly (submodule moved on),
  it is reported and the .patch file is left in place for manual `git apply --3way`.

  ROBUSTNESS NOTES (why this is not just `git apply <file>`):
    * Patch files may have been written by PowerShell redirection (UTF-16 LE/BE w/ BOM).
      `git apply` only understands UTF-8/ASCII and otherwise reports
      "No valid patches in input". Get-Utf8PatchPath normalizes any encoding to a
      UTF-8 (no BOM) temp copy before applying.
    * git writes progress/errors to stderr; capturing that with `2>&1` while
      $ErrorActionPreference='Stop' turns it into a *terminating* error (PS 5.1
      NativeCommandError) that aborts the whole bootstrap. Invoke-Git captures
      output without that trap and returns the real exit code.
    * If the submodule still has stashes, the WIP almost certainly survived the reset.
      Re-applying would create DUPLICATE stashes, so we skip and report instead.

.PARAMETER BundlePath        Recovery bundle root (auto-detect F:\ then E:\).
.PARAMETER ClaudeToolsRoot   Default D:\claudetools.
#>
[CmdletBinding()]
param([string]$BundlePath,[string]$ClaudeToolsRoot='D:\claudetools')
$ErrorActionPreference='Stop'

# Read a patch regardless of encoding (UTF-16 LE/BE +/- BOM, UTF-8 +/- BOM) and return
# the path to a normalized UTF-8 (no BOM) temp copy that `git apply` can parse.
function Get-Utf8PatchPath($path){
  $bytes = [System.IO.File]::ReadAllBytes($path)
  if     ($bytes.Length -ge 2 -and $bytes[0] -eq 0xFF -and $bytes[1] -eq 0xFE) { $text = [System.Text.Encoding]::Unicode.GetString($bytes,2,$bytes.Length-2) }
  elseif ($bytes.Length -ge 2 -and $bytes[0] -eq 0xFE -and $bytes[1] -eq 0xFF) { $text = [System.Text.Encoding]::BigEndianUnicode.GetString($bytes,2,$bytes.Length-2) }
  elseif ($bytes.Length -ge 3 -and $bytes[0] -eq 0xEF -and $bytes[1] -eq 0xBB -and $bytes[2] -eq 0xBF) { $text = [System.Text.Encoding]::UTF8.GetString($bytes,3,$bytes.Length-3) }
  else {
    # No BOM: detect UTF-16 LE without BOM by counting interleaved NUL bytes in the head.
    $nul = 0; $n = [Math]::Min(64,$bytes.Length)
    for ($i=0; $i -lt $n; $i++) { if ($bytes[$i] -eq 0) { $nul++ } }
    if ($nul -gt 8) { $text = [System.Text.Encoding]::Unicode.GetString($bytes) }
    else            { $text = [System.Text.Encoding]::UTF8.GetString($bytes) }
  }
  $text = $text -replace "`r`n","`n"   # normalize to LF so git apply is happy
  $tmp = [System.IO.Path]::GetTempFileName()
  [System.IO.File]::WriteAllText($tmp, $text, (New-Object System.Text.UTF8Encoding($false)))
  return $tmp
}

# Run git without letting native stderr (under $ErrorActionPreference='Stop') become a
# terminating error. Returns [pscustomobject]@{ Code; Output }.
function Invoke-Git([string[]]$GitArgs){
  $old = $ErrorActionPreference; $ErrorActionPreference = 'Continue'
  try { $out = (& git @GitArgs 2>&1 | Out-String); $code = $LASTEXITCODE }
  finally { $ErrorActionPreference = $old }
  [pscustomobject]@{ Code = $code; Output = ($out).Trim() }
}

if (-not $BundlePath) { foreach ($d in 'F:','E:','D:') { if (Test-Path "$d\claudetools-recovery\at-risk-work") { $BundlePath="$d\claudetools-recovery"; break } } }
$aw = "$BundlePath\at-risk-work"
if (-not $BundlePath -or -not (Test-Path $aw)) { Write-Host "[INFO] no at-risk-work folder found in bundle - nothing to restore"; return }
Write-Host "[INFO] restoring at-risk WIP from $aw" -ForegroundColor Cyan

function Have-Git($repo){ Test-Path "$repo\.git" }

# ---- guru-rmm stashes ----
$rmm = "$ClaudeToolsRoot\projects\msp-tools\guru-rmm"
if ((Test-Path "$aw\guru-rmm") -and (Have-Git $rmm)) {
  $existing = (Invoke-Git @('-C',$rmm,'stash','list')).Output
  if ($existing) {
    Write-Host "[SKIP] guru-rmm already has stashes (local WIP survived the reset) - not re-applying to avoid duplicates:" -ForegroundColor Yellow
    Write-Host $existing
    Write-Host "       Bundle patches remain in $aw\guru-rmm; apply by hand if you really need them." -ForegroundColor Yellow
  }
  elseif ((Invoke-Git @('-C',$rmm,'status','--porcelain')).Output) {
    Write-Host "[WARN] guru-rmm working tree is dirty; skipping auto-restore to avoid mixing changes. Apply patches in $aw\guru-rmm manually." -ForegroundColor Yellow
  } else {
    # highest N first so stash0 lands at stash@{0}
    $patches = Get-ChildItem "$aw\guru-rmm" -Filter '*.patch' | Sort-Object Name -Descending
    foreach ($p in $patches) {
      $u8 = Get-Utf8PatchPath $p.FullName
      try {
        $chk = Invoke-Git @('-C',$rmm,'apply','--check','--3way',$u8)
        if ($chk.Code -ne 0) { Write-Host "[WARN] won't apply cleanly, left for manual restore: $($p.Name) ($($chk.Output))" -ForegroundColor Yellow; continue }
        Invoke-Git @('-C',$rmm,'apply','--3way',$u8) | Out-Null
        Invoke-Git @('-C',$rmm,'stash','push','-u','-m',"restored WIP: $($p.BaseName)") | Out-Null
        Write-Host "[OK]   re-stashed guru-rmm: $($p.BaseName)" -ForegroundColor Green
      } finally { Remove-Item $u8 -Force -ErrorAction SilentlyContinue }
    }
    Write-Host "[INFO] guru-rmm stashes now:" -ForegroundColor Cyan
    Write-Host (Invoke-Git @('-C',$rmm,'stash','list')).Output
  }
}

# ---- guru-connect untracked diff ----
$gc = "$ClaudeToolsRoot\projects\msp-tools\guru-connect"
$diff = "$aw\guru-connect\tmp-spec018.diff"
if ((Test-Path $diff) -and (Test-Path $gc)) {
  if (Test-Path "$gc\tmp-spec018.diff") {
    Write-Host "[SKIP] guru-connect\tmp-spec018.diff already present in repo (survived the reset) - not overwriting." -ForegroundColor Yellow
  } else {
    Copy-Item $diff "$gc\tmp-spec018.diff" -Force
    Write-Host "[OK]   guru-connect\tmp-spec018.diff restored (untracked working file - 'git apply --3way tmp-spec018.diff' to apply it)" -ForegroundColor Green
  }
}
Write-Host "[DONE] at-risk WIP restore" -ForegroundColor Cyan
