autotag.yaml

name: Auto CalVer Tag on Master Push

on:
  push:
    branches:
      - master

jobs:
  calver-tag:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Set CalVer date
        id: calver
        run: |
          # Get current date in YYYY.MM.DD format
          date_tag=$(date +'%Y.%m.%d')
          echo "base_tag=$date_tag" >> $GITHUB_OUTPUT

      - name: Fetch all tags
        run: |
          git fetch --tags

      - name: Determine next CalVer tag
        id: next_tag
        run: |
          base=${{ steps.calver.outputs.base_tag }}
          # List all existing tags that match today's date
          existing=$(git tag --list "${base}*")

          if ! echo "$existing" | grep -q "^$base$"; then
            # No base tag exists yet, use the base tag (no suffix)
            new_tag="$base"
          else
            # Base tag exists, find the highest numbered suffix
            max=1  # because base tag is already used
            for tag in $existing; do
              suffix=$(echo $tag | sed -n "s/^$base\.//p")
              if [[ "$suffix" =~ ^[0-9]+$ && "$suffix" -gt "$max" ]]; then
                max=$suffix
              fi
            done
            new_tag="$base.$((max + 1))"
          fi

          echo "New tag: $new_tag"
          echo "new_tag=$new_tag" >> $GITHUB_OUTPUT

      - name: Create and push new tag
        run: |
          git config user.name "github-actions"
          git config user.email "github-actions@github.com"
          git tag ${{ steps.next_tag.outputs.new_tag }}
          git push origin ${{ steps.next_tag.outputs.new_tag }}