name: CI

# Two jobs, in order:
#
#   gate — `task check` (structure, frontmatter, manifest/tag parity) plus
#          `task test` (hooks, doctor, release-skip). Runs on every push and
#          every PR. Before this existed the suite ran nowhere: CI reported
#          green having tested nothing (#22).
#
#   tag  — auto-tags a push to main with a semver bump derived from the latest
#          commit footer:
#            Bump-Type: major  → vX.0.0
#            Bump-Type: minor  → v0.Y.0
#            (default)         → v0.0.Z (patch)
#          Skips when the commit carries the `Skip-Release: true` trailer (the
#          tagger's own manifest bump) to prevent recursion. Gated on `gate`,
#          so a red check cannot ship a tag.

"on":
  push:
    branches: ["**"]
  pull_request:
    branches: [main]

jobs:
  gate:
    name: Check / Test
    runs-on: self-hosted
    steps:
      - uses: actions/checkout@v4
        with:
          # `task check` compares plugin.json's version to `git describe`;
          # a shallow checkout has no tags and would skip that assertion.
          fetch-depth: 0

      - name: Verify toolchain
        run: task --version

      - name: Structure gate
        run: task check

      - name: Shell test suite
        run: task test

  tag:
    name: Tag release
    needs: gate
    runs-on: self-hosted
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    steps:
      - name: checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          token: ${{ secrets.GITEA_TOKEN }}

      - name: derive next version
        id: bump
        run: |
          set -euo pipefail
          last_commit=$(git log -1 --pretty=%B)
          # Delegated to bin/should-skip-release so the rule is covered by
          # tests/release_skip_test.sh rather than living untested in YAML.
          if printf '%s\n' "$last_commit" | sh bin/should-skip-release; then
            echo "skipping — commit carries the Skip-Release trailer"
            echo "skip=true" >> "$GITHUB_OUTPUT"
            exit 0
          fi
          latest=$(git describe --tags --abbrev=0 2>/dev/null || echo "v0.0.0")
          major=$(echo "$latest" | sed -E 's/^v([0-9]+)\.([0-9]+)\.([0-9]+)$/\1/')
          minor=$(echo "$latest" | sed -E 's/^v([0-9]+)\.([0-9]+)\.([0-9]+)$/\2/')
          patch=$(echo "$latest" | sed -E 's/^v([0-9]+)\.([0-9]+)\.([0-9]+)$/\3/')
          bump=$(printf '%s' "$last_commit" | grep -iE '^Bump-Type:' | head -1 | awk '{print tolower($2)}' || true)
          case "$bump" in
            major) major=$((major + 1)); minor=0; patch=0 ;;
            minor) minor=$((minor + 1)); patch=0 ;;
            *)     patch=$((patch + 1)) ;;
          esac
          next="v${major}.${minor}.${patch}"
          echo "previous=$latest"
          echo "bump=${bump:-patch}"
          echo "next=$next"
          echo "tag=$next" >> "$GITHUB_OUTPUT"
          echo "skip=false" >> "$GITHUB_OUTPUT"

      - name: tag + push
        if: steps.bump.outputs.skip != 'true'
        env:
          TAG: ${{ steps.bump.outputs.tag }}
          GITEA_ACTOR: ${{ gitea.actor }}
          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
        run: |
          set -euo pipefail
          git config user.name "${GITEA_ACTOR}"
          git config user.email "${GITEA_ACTOR}@noreply.gitea.d-ma.be"

          # The tag goes up FIRST and on its own. It names the commit this run
          # checked out and can never be rejected, however far main has moved.
          git tag -a "$TAG" -m "release $TAG"
          git push origin "$TAG"
          echo "pushed $TAG"

          # The manifest bump is a separate concern and must land on whatever
          # main is NOW. The runner is maxParallel=1 and shared with other
          # repos, so a job routinely starts several commits after its own —
          # pushing this run's stale HEAD to main is then rejected
          # non-fast-forward, which is how v0.10.0 ended up tagged with the
          # manifest still reading 0.9.0.
          #
          # Claude Code gates plugin updates on this field: if it does not
          # move, installed hosts never see the release. `task check` asserts
          # the manifest is not behind the latest tag, so a failure here is a
          # red main, not a cosmetic miss.
          manifest=.claude-plugin/plugin.json
          version="${TAG#v}"

          for attempt in 1 2 3; do
            git fetch --quiet origin main
            git checkout --quiet -B release-bump origin/main

            current=$(sed -n 's/.*"version"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' "$manifest" | head -1)
            if [ "$current" = "$version" ]; then
              echo "manifest already at $version"
              exit 0
            fi
            # A later run may have bumped past us while this one waited.
            if [ "$(sh bin/newer-version "$current" "$version")" = "$current" ]; then
              echo "manifest is $current, already newer than $version — leaving it"
              exit 0
            fi

            sed -i "s/\"version\"[[:space:]]*:[[:space:]]*\"$current\"/\"version\": \"$version\"/" "$manifest"
            git add "$manifest"
            # The trailer below stops this push from re-triggering the tagger.
            git commit -m "chore(release): plugin.json version $version" -m "Skip-Release: true"

            # skills#46. This commit is pushed with secrets.GITEA_TOKEN, and a
            # push authenticated with the Actions token does NOT trigger
            # workflows -- deliberate platform behaviour to stop CI recursing.
            # `Skip-Release: true` stops the tagger recursing; nothing stopped
            # the whole run, `gate` included, from never firing on this commit.
            #
            # So every release left main's HEAD with zero CI runs. Measured:
            # 6cc224f (0.19.4) and f031c2b (0.19.5) each have none, and the
            # koala cluster's CIHeadUncovered{repo=skills} had been firing on it
            # for 85 hours -- an alert that can only be cleared by an unrelated
            # human push.
            #
            # The commit is not cosmetic: plugin.json's version is what Claude
            # Code gates plugin updates on, `task check` asserts it is not
            # behind the latest tag, and the sed-and-retry logic above already
            # shipped a mismatched manifest once (v0.10.0 reading 0.9.0).
            #
            # Gating it HERE rather than re-triggering CI afterwards: the commit
            # is produced here, so it can be validated here, at the cost of one
            # `task check` instead of a second full run -- and with no recursion
            # risk to reintroduce.
            if ! task check; then
              echo "::error::the release-bump commit fails task check -- not pushing it" >&2
              exit 1
            fi

            if git push origin HEAD:main; then
              echo "bumped $manifest to $version"
              exit 0
            fi
            echo "main moved while bumping — retry $attempt"
          done

          echo "could not land the manifest bump after 3 attempts" >&2
          exit 1