name: version check
permissions:
  contents: read

on:
  pull_request:
    branches: [master]

jobs:
  # PR check: waku.nimble version must be >= the nearest tag reachable from
  # this branch (`git describe --tags --abbrev=0`, i.e. ancestor-aware).
  # Because we check out the PR HEAD (not the simulated merge ref), a branch
  # that predates a release tag does not see that tag in its history, so a
  # newly pushed tag does NOT break in-flight PRs. Once the branch merges/
  # rebases past the tag, the bump is then enforced. This keeps waku.nimble
  # fixed as early as possible, independent of whether a release is cut.
  # The exact tag==nimble guarantee at release time lives in
  # release-assets.yml, which gates artifact publishing on it.
  nimble-not-behind-tag:
    runs-on: ubuntu-22.04
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
          ref: ${{ github.event.pull_request.head.sha }}
      - name: Compare waku.nimble version with nearest ancestor tag
        run: |
          set -euo pipefail
          NIMBLE_VERSION=$(grep -m1 '^version = ' waku.nimble | sed -E 's/version = "([^"]+)"/\1/')
          # Nearest tag reachable from HEAD; --abbrev=0 drops the -<n>-g<sha>
          # suffix so we get the bare tag (e.g. v0.38.0).
          BASE_TAG=$(git describe --tags --abbrev=0 2>/dev/null || echo "")
          BASE_TAG=${BASE_TAG#v}
          # Compare on the base version, ignoring any -rc.N prerelease suffix.
          BASE_TAG=${BASE_TAG%%-*}
          echo "waku.nimble version: ${NIMBLE_VERSION}"
          echo "ancestor git tag:    ${BASE_TAG:-<none>}"
          if [ -z "${BASE_TAG}" ]; then
            echo "No ancestor release tag; skipping."
            exit 0
          fi
          # lowest of the two by version sort must be the tag => nimble >= tag
          LOWEST=$(printf '%s\n%s\n' "${NIMBLE_VERSION}" "${BASE_TAG}" | sort -V | head -1)
          if [ "${LOWEST}" != "${BASE_TAG}" ] && [ "${NIMBLE_VERSION}" != "${BASE_TAG}" ]; then
            echo "::error::waku.nimble version (${NIMBLE_VERSION}) is behind its"
            echo "::error::ancestor git tag (v${BASE_TAG}). Bump 'version' in waku.nimble."
            exit 1
          fi
          echo "OK: waku.nimble is not behind its ancestor tag."