Cleanup unchanged forked repos using gh cli

gh-fork-cleanup

#!/usr/bin/env zsh

# Array to store repos with no changes
unchanged_forks=()

# Use process substitution < <() so the array stays available after the loop
while read p_repo f_repo; do
  
  echo "---------------------------------------------------"
  echo "🔍 Checking Fork: $f_repo"

  # 1. Fetch branch names
  p_branch=$(gh repo view "$p_repo" --json defaultBranchRef --jq '.defaultBranchRef.name' 2>/dev/null)
  f_branch=$(gh repo view "$f_repo" --json defaultBranchRef --jq '.defaultBranchRef.name' 2>/dev/null)

  if [[ -z "$p_branch" || -z "$f_branch" ]]; then
    echo "   ❌ SKIP: Could not retrieve branch names."
    continue
  fi

  # 2. API Comparison
  compare_url="repos/$f_repo/compare/${p_repo%/*}:${p_branch}...${f_repo%/*}:${f_branch}"
  res=$(gh api "$compare_url" --jq '{status: .status, ahead: .ahead_by}' 2>/dev/null)
  
  if [[ -z "$res" ]]; then
    echo "   ❌ ERROR: API 404 for $f_repo"
    continue
  fi

  diff_status=$(echo "$res" | jq -r .status)
  ahead_count=$(echo "$res" | jq -r .ahead)

  # 3. Collect if no changes (ahead is 0)
  if [[ "$ahead_count" == "0" ]]; then
    echo "   ✅ Found unchanged repo: $f_repo"
    unchanged_forks+=("$f_repo")
  else
    echo "   🔸 Modified: Ahead by $ahead_count"
  fi

done < <(gh repo list --fork --limit 100 --json nameWithOwner,parent --jq '.[] | select(.parent != null) | "\(.parent.owner.login)/\(.parent.name) \(.nameWithOwner)"')

# --- Final Prompt ---

if [[ ${#unchanged_forks[@]} -eq 0 ]]; then
  echo "\n✨ No unchanged forks found."
  exit 0
fi

echo "\n⚠️  The following ${#unchanged_forks[@]} forks have NO personal changes:"
printf ' - %s\n' "${unchanged_forks[@]}"

# In Zsh, we read from the terminal specifically to avoid issues with the pipe
echo -n "\n❓ Delete these ${#unchanged_forks[@]} forks? (y/N): "
read -r confirm

if [[ "$confirm" =~ ^[Yy]$ ]]; then
  for repo in "${unchanged_forks[@]}"; do
    echo "🗑️  Deleting $repo..."
    gh repo delete "$repo" --yes
  done
  echo "✅ Cleanup complete."
else
  echo "❌ Cancelled."
fi