tag-release.yml

name: Tag and draft release

# Cuts a release for the version on main: builds release notes (from the merged
# release PR body, falling back to auto-generated notes), creates a *draft*
# GitHub Release, then pushes the version tag. The tag push triggers the
# dist-generated release.yml, which builds the cross-platform binaries and
# installers, uploads them to the draft, and undrafts it. The draft must exist
# before the tag lands — dist uploads into it rather than creating its own.

on:
  push:
    branches: [main]

jobs:
  release:
    name: Tag and draft GitHub release
    runs-on: ubuntu-latest
    permissions:
      contents: write
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
          # Push the tag as the PAT, not the default GITHUB_TOKEN: tag pushes made
          # with GITHUB_TOKEN do not trigger other workflows, so the dist
          # release.yml (push: tags) would never fire. Same token release-pr.yml
          # uses so the PRs it opens trigger CI.
          token: ${{ secrets.RELEASE_PR_TOKEN }}

      - name: Read version from Cargo.toml
        id: version
        run: |
          VERSION=$(grep -m1 '^version = ' Cargo.toml | sed -E 's/version = "(.*)"/\1/')
          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
          echo "tag=v$VERSION" >> "$GITHUB_OUTPUT"
          echo "Version on main: $VERSION"

      - name: Check if tag already exists (idempotency)
        id: tag-check
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          if git rev-parse "${{ steps.version.outputs.tag }}" >/dev/null 2>&1; then
            echo "Tag ${{ steps.version.outputs.tag }} already exists — skipping release."
            echo "exists=true" >> "$GITHUB_OUTPUT"
          else
            echo "exists=false" >> "$GITHUB_OUTPUT"
            # A draft without a tag means a previous run failed between
            # draft-create and tag-push; delete it so this run starts clean.
            if gh release view "${{ steps.version.outputs.tag }}" --json isDraft --jq '.isDraft' 2>/dev/null | grep -q true; then
              echo "Deleting stale draft release for ${{ steps.version.outputs.tag }}."
              gh release delete "${{ steps.version.outputs.tag }}" --yes
            fi
          fi

      - name: Build release notes
        if: steps.tag-check.outputs.exists == 'false'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          PR_BODY=$(gh pr list \
            --state merged \
            --base main \
            --limit 1 \
            --json body \
            --jq '.[0].body // ""')

          if [ -n "$PR_BODY" ] && ! echo "$PR_BODY" | grep -q "release-notes:todo"; then
            echo "Using release PR body for notes."
            printf '%s\n' "$PR_BODY" > /tmp/release-notes.md
          else
            echo "Falling back to auto-generated notes."
            PREVIOUS_TAG=$(git tag --sort=-creatordate \
              | grep -v "^${{ steps.version.outputs.tag }}$" \
              | head -n1)
            if [ -n "$PREVIOUS_TAG" ]; then
              gh api "repos/${{ github.repository }}/releases/generate-notes" \
                -f tag_name="${{ steps.version.outputs.tag }}" \
                -f previous_tag_name="$PREVIOUS_TAG" \
                --jq '.body' > /tmp/release-notes.md
            else
              gh api "repos/${{ github.repository }}/releases/generate-notes" \
                -f tag_name="${{ steps.version.outputs.tag }}" \
                --jq '.body' > /tmp/release-notes.md
            fi
          fi

          echo "--- Release notes preview ---"
          cat /tmp/release-notes.md
          echo "--- end preview ---"

      - name: Create draft GitHub release
        if: steps.tag-check.outputs.exists == 'false'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          gh release create "${{ steps.version.outputs.tag }}" \
            --draft \
            --target "$GITHUB_SHA" \
            --title "eval-magic ${{ steps.version.outputs.tag }}" \
            --notes-file /tmp/release-notes.md

      # Last on purpose: the tag push triggers the dist release workflow, which
      # expects the draft above to already exist.
      - name: Create and push tag
        if: steps.tag-check.outputs.exists == 'false'
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
          git tag "${{ steps.version.outputs.tag }}"
          git push origin "${{ steps.version.outputs.tag }}"