Troubleshooting

(
  grace_config_override=''
  grace_config_dir=${grace_config_override:-${COPILOT_HOME:-"$HOME/.copilot"}}
  case "$grace_config_dir" in
    /*) ;;
    *) printf '%s\n' 'Stop: supply an absolute path.' >&2; exit 1 ;;
  esac
  if [ -L "$grace_config_dir" ] || [ ! -d "$grace_config_dir" ]; then
    printf '%s\n' 'Stop: configuration directory is absent, invalid, or a symbolic link.' >&2; exit 1
  fi
  grace_cache="$grace_config_dir/mcp-oauth-config"
  if [ -L "$grace_cache" ]; then
    printf '%s\n' 'Stop: the cache is a symbolic link.' >&2; exit 1
  fi
  if [ ! -e "$grace_cache" ]; then
    printf '%s\n' 'Cache absent: no change. The keychain may be in use.'; exit 0
  fi
  if [ ! -d "$grace_cache" ]; then
    printf '%s\n' 'Stop: the cache exists but is not a directory.' >&2; exit 1
  fi
  grace_backup="$grace_config_dir/mcp-oauth-backup-$(date +%Y%m%d-%H%M%S)"
  (umask 077; mkdir "$grace_backup") || {
    printf '%s\n' 'Stop: backup already exists or cannot be created. Nothing moved.' >&2; exit 1
  }
  mv "$grace_cache" "$grace_backup/mcp-oauth-config" || exit 1
  printf 'Backup: %s\n' "$grace_backup"
)

& {
  $graceConfigOverride = ''
  $graceConfigDir = if ($graceConfigOverride) { $graceConfigOverride } elseif ($env:COPILOT_HOME) { $env:COPILOT_HOME } else { Join-Path $HOME '.copilot' }
  if (-not [IO.Path]::IsPathRooted($graceConfigDir) -or $graceConfigDir -match '^[A-Za-z]:(?![\\/])|^\\(?!\\)') { throw 'Stop: supply an absolute path.' }
  $graceDir = Get-Item -LiteralPath $graceConfigDir -Force -ErrorAction Stop
  if (-not $graceDir.PSIsContainer -or ($graceDir.Attributes -band [IO.FileAttributes]::ReparsePoint)) { throw 'Stop: configuration directory is invalid or linked.' }
  $graceCache = Join-Path $graceConfigDir 'mcp-oauth-config'
  $graceItem = Get-Item -LiteralPath $graceCache -Force -ErrorAction SilentlyContinue
  if ($null -eq $graceItem) { Write-Host 'Cache absent: no change. The keychain may be in use.'; return }
  if (-not $graceItem.PSIsContainer -or ($graceItem.Attributes -band [IO.FileAttributes]::ReparsePoint)) { throw 'Stop: the cache is invalid or linked.' }
  $graceBackup = Join-Path $graceConfigDir ('mcp-oauth-backup-' + (Get-Date -Format 'yyyyMMdd-HHmmss'))
  if (Test-Path -LiteralPath $graceBackup) { throw 'Stop: backup already exists. Nothing moved.' }
  New-Item -ItemType Directory -Path $graceBackup -ErrorAction Stop | Out-Null
  Move-Item -LiteralPath $graceCache -Destination (Join-Path $graceBackup 'mcp-oauth-config') -ErrorAction Stop
  Write-Host "Backup: $graceBackup"
}

(
  grace_backup='/absolute/path/mcp-oauth-backup-YYYYMMDD-HHMMSS'
  case "$grace_backup" in /*) ;; *) printf '%s\n' 'Stop: an absolute path is required.' >&2; exit 1 ;; esac
  grace_cache="$(dirname "$grace_backup")/mcp-oauth-config"
  if [ -L "$grace_backup" ] || [ -L "$grace_backup/mcp-oauth-config" ] || [ ! -d "$grace_backup/mcp-oauth-config" ]; then
    printf '%s\n' 'Stop: backup is absent, invalid, or a symbolic link.' >&2; exit 1
  fi
  if [ -e "$grace_cache" ] || [ -L "$grace_cache" ]; then
    printf '%s\n' 'Stop: a cache already exists. Back it up before restoring.' >&2; exit 1
  fi
  mv "$grace_backup/mcp-oauth-config" "$grace_cache" || exit 1
  printf '%s\n' 'Previous cache restored.'
)

& {
  $graceBackup = 'C:\absolute\path\mcp-oauth-backup-YYYYMMDD-HHMMSS'
  if (-not [IO.Path]::IsPathRooted($graceBackup) -or $graceBackup -match '^[A-Za-z]:(?![\\/])|^\\(?!\\)') { throw 'Stop: an absolute path is required.' }
  $graceDir = Get-Item -LiteralPath $graceBackup -Force -ErrorAction Stop
  $graceSource = Get-Item -LiteralPath (Join-Path $graceBackup 'mcp-oauth-config') -Force -ErrorAction Stop
  if (-not $graceDir.PSIsContainer -or -not $graceSource.PSIsContainer -or ($graceDir.Attributes -band [IO.FileAttributes]::ReparsePoint) -or ($graceSource.Attributes -band [IO.FileAttributes]::ReparsePoint)) { throw 'Stop: backup is invalid or linked.' }
  $graceCache = Join-Path (Split-Path -Parent $graceBackup) 'mcp-oauth-config'
  if (Get-Item -LiteralPath $graceCache -Force -ErrorAction SilentlyContinue) { throw 'Stop: a cache already exists. Back it up before restoring.' }
  Move-Item -LiteralPath $graceSource.FullName -Destination $graceCache -ErrorAction Stop
  Write-Host 'Previous cache restored.'
}