cleanup-branches.yml

name: Cleanup stale workflow branches

on:
  schedule:
    # Run every Sunday at 00:00 UTC
    - cron: "0 0 * * 0"
  workflow_dispatch:
    inputs:
      days_old:
        description: "Delete branches older than this many days"
        type: number
        default: 14
        required: false
      dry_run:
        description: "Dry run (list branches without deleting)"
        type: boolean
        default: false
        required: false

permissions:
  contents: write

jobs:
  cleanup-branches:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Delete stale workflow branches
        env:
          GH_TOKEN: ${{ github.token }}
        run: |
          set -euo pipefail

          # Configuration
          days_old="${{ inputs.days_old || 14 }}"
          dry_run="${{ inputs.dry_run || false }}"
          branch_pattern="workflow/v"

          echo "Configuration:"
          echo "  Days old threshold: ${days_old}"
          echo "  Dry run: ${dry_run}"
          echo "  Branch pattern: ${branch_pattern}*"
          echo ""

          # Calculate cutoff date
          cutoff_date=$(date -d "${days_old} days ago" +%Y-%m-%dT%H:%M:%SZ 2>/dev/null || \
                        date -v-${days_old}d +%Y-%m-%dT%H:%M:%SZ)
          cutoff_epoch=$(date -d "${cutoff_date}" +%s 2>/dev/null || \
                         date -j -f "%Y-%m-%dT%H:%M:%SZ" "${cutoff_date}" +%s)

          echo "Cutoff date: ${cutoff_date}"
          echo ""

          # Get remote branches matching pattern
          git fetch --prune origin

          deleted_count=0
          skipped_count=0

          while IFS= read -r ref; do
            [[ -z "$ref" ]] && continue

            branch="${ref#refs/remotes/origin/}"
            [[ "$branch" != ${branch_pattern}* ]] && continue

            # Get last commit date for this branch
            last_commit_date=$(git log -1 --format=%cI "origin/${branch}" 2>/dev/null || echo "")
            if [[ -z "$last_commit_date" ]]; then
              echo "[SKIP] ${branch} (no commit date)"
              skipped_count=$((skipped_count + 1))
              continue
            fi

            # Convert to epoch for comparison
            commit_epoch=$(date -d "${last_commit_date}" +%s 2>/dev/null || \
                           date -j -f "%Y-%m-%dT%H:%M:%S%z" "${last_commit_date}" +%s 2>/dev/null || \
                           echo "0")

            if [[ "$commit_epoch" -lt "$cutoff_epoch" ]]; then
              if [[ "$dry_run" == "true" ]]; then
                echo "[DRY-RUN] Would delete: ${branch} (last commit: ${last_commit_date})"
              else
                echo "[DELETE] ${branch} (last commit: ${last_commit_date})"
                git push origin --delete "${branch}" || {
                  echo "  Failed to delete ${branch}"
                  skipped_count=$((skipped_count + 1))
                  continue
                }
              fi
              deleted_count=$((deleted_count + 1))
            else
              echo "[KEEP] ${branch} (last commit: ${last_commit_date})"
              skipped_count=$((skipped_count + 1))
            fi
          done < <(git for-each-ref --format='%(refname)' refs/remotes/origin/)

          echo ""
          echo "Summary:"
          if [[ "$dry_run" == "true" ]]; then
            echo "  Would delete: ${deleted_count} branches"
          else
            echo "  Deleted: ${deleted_count} branches"
          fi
          echo "  Kept/Skipped: ${skipped_count} branches"