auto-version.yml

name: Auto Version on PR Merge

on:
  pull_request:
    types: [closed]
    branches: [main]

permissions:
  contents: read

jobs:
  version-and-release:
    name: Version & Tag
    if: github.event.pull_request.merged == true
    runs-on: ubuntu-latest

    steps:
      - name: Checkout main with full history
        uses: actions/checkout@v5
        with:
          ref: main
          fetch-depth: 0
          fetch-tags: true
          token: ${{ secrets.RELEASE_TOKEN }}

      - name: Get latest semver tag from main
        id: latest
        run: |
          LATEST=$(git tag --sort=-v:refname \
            | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$' \
            | head -n1)

          if [ -z "$LATEST" ]; then
            echo "No existing semver tags found, starting from v0.0.0"
            LATEST="v0.0.0"
          fi

          VERSION="${LATEST#v}"
          {
            echo "tag=$LATEST"
            echo "version=$VERSION"
            echo "major=$(echo "$VERSION" | cut -d. -f1)"
            echo "minor=$(echo "$VERSION" | cut -d. -f2)"
            echo "patch=$(echo "$VERSION" | cut -d. -f3)"
          } >> "$GITHUB_OUTPUT"
          echo "Latest tag on main: $LATEST"

      - name: Check for version tag on PR commits
        id: pr-tag
        env:
          PR_HEAD_SHA: ${{ github.event.pull_request.head.sha }}
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
        run: |
          # Fetch the PR head ref to ensure we have all PR commits and their tags
          git fetch origin "$PR_HEAD_SHA" --tags 2>/dev/null || true

          # Find the merge base between main and the PR head
          MERGE_BASE=$(git merge-base "$PR_BASE_SHA" "$PR_HEAD_SHA" 2>/dev/null || echo "$PR_BASE_SHA")

          echo "Merge base: $MERGE_BASE"
          echo "PR head:    $PR_HEAD_SHA"

          PR_TAG=""
          for SHA in $(git log --format=%H "${MERGE_BASE}..${PR_HEAD_SHA}" 2>/dev/null); do
            TAG=$(git tag --points-at "$SHA" 2>/dev/null \
              | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+(-[a-zA-Z0-9.-]+)?$' \
              | head -n1)
            if [ -n "$TAG" ]; then
              PR_TAG="$TAG"
              echo "Found version tag on PR commit $SHA: $TAG"
              break
            fi
          done

          if [ -n "$PR_TAG" ]; then
            echo "tag=$PR_TAG" >> "$GITHUB_OUTPUT"
            echo "has_tag=true" >> "$GITHUB_OUTPUT"
          else
            echo "No version tag found on PR commits"
            echo "tag=" >> "$GITHUB_OUTPUT"
            echo "has_tag=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Calculate next version
        id: next
        run: |
          if [ "${{ steps.pr-tag.outputs.has_tag }}" == "true" ]; then
            NEXT="${{ steps.pr-tag.outputs.tag }}"
            echo "Using version from PR tag: $NEXT"
          else
            MAJOR=${{ steps.latest.outputs.major }}
            MINOR=${{ steps.latest.outputs.minor }}
            PATCH=${{ steps.latest.outputs.patch }}
            NEXT="v${MAJOR}.${MINOR}.$((PATCH + 1))"
            echo "Auto-bumping patch: ${{ steps.latest.outputs.tag }} -> $NEXT"
          fi

          echo "version=${NEXT#v}" >> "$GITHUB_OUTPUT"
          echo "tag=$NEXT" >> "$GITHUB_OUTPUT"

      - name: Update CHANGELOG (tagged PRs only)
        if: steps.pr-tag.outputs.has_tag == 'true'
        env:
          PR_TITLE: ${{ github.event.pull_request.title }}
          PR_BODY: ${{ github.event.pull_request.body }}
          PR_NUMBER: ${{ github.event.pull_request.number }}
          PR_URL: ${{ github.event.pull_request.html_url }}
          NEXT_VERSION: ${{ steps.next.outputs.version }}
        run: |
          DATE=$(date +%Y-%m-%d)

          # Build the changelog entry in a temp file (using env vars to avoid injection)
          {
            echo ""
            echo "## [v${NEXT_VERSION}] - ${DATE}"
            echo ""
            echo "### ${PR_TITLE} ([#${PR_NUMBER}](${PR_URL}))"
            echo ""
            echo "${PR_BODY}"
            echo ""
          } > /tmp/changelog-entry.md

          # Insert after the marker line in CHANGELOG.md
          if [ -f CHANGELOG.md ]; then
            # Find the marker line number
            MARKER_LINE=$(grep -n '<!-- auto-managed' CHANGELOG.md | head -n1 | cut -d: -f1)
            if [ -n "$MARKER_LINE" ]; then
              # Split file at marker, insert entry between
              head -n "$MARKER_LINE" CHANGELOG.md > /tmp/changelog-top.md
              tail -n +"$((MARKER_LINE + 1))" CHANGELOG.md > /tmp/changelog-bottom.md
              cat /tmp/changelog-top.md /tmp/changelog-entry.md /tmp/changelog-bottom.md > CHANGELOG.md
            else
              # No marker found, prepend after first line (the heading)
              head -n 1 CHANGELOG.md > /tmp/changelog-top.md
              tail -n +2 CHANGELOG.md > /tmp/changelog-bottom.md
              cat /tmp/changelog-top.md /tmp/changelog-entry.md /tmp/changelog-bottom.md > CHANGELOG.md
            fi
          else
            echo "::warning::CHANGELOG.md not found, creating it"
            {
              echo "# Changelog"
              echo ""
              echo "All notable changes to the PRIME FHIR Converter will be documented in this file."
              echo ""
              echo "The format is based on [Keep a Changelog](https://keepachangelog.com/)."
              echo ""
              echo "<!-- auto-managed: new entries are prepended below this line -->"
              cat /tmp/changelog-entry.md
            } > CHANGELOG.md
          fi

          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git add CHANGELOG.md
          git commit -m "docs: update CHANGELOG for v${NEXT_VERSION}"
          git push origin main

      - name: Create and push version tag
        run: |
          TAG="${{ steps.next.outputs.tag }}"

          # Check if tag already exists
          if git rev-parse "$TAG" >/dev/null 2>&1; then
            echo "::error::Tag $TAG already exists"
            exit 1
          fi

          git tag "$TAG"
          git push origin "$TAG"
          echo "Created and pushed tag: $TAG"

      - name: Trigger build-and-publish workflow
        env:
          GH_TOKEN: ${{ secrets.RELEASE_TOKEN }}
        run: |
          VERSION="${{ steps.next.outputs.version }}"
          echo "Triggering build-and-publish with version=${VERSION}, publish=true"
          gh workflow run build-and-publish.yml \
            -f version="${VERSION}" \
            -f publish=true

      - name: Summary
        run: |
          {
            echo "### Auto Version Complete"
            echo ""
            echo "| Detail | Value |"
            echo "|--------|-------|"
            echo "| Previous tag | \`${{ steps.latest.outputs.tag }}\` |"
            echo "| New tag | \`${{ steps.next.outputs.tag }}\` |"
            echo "| PR had version tag | ${{ steps.pr-tag.outputs.has_tag }} |"
            echo "| CHANGELOG updated | ${{ steps.pr-tag.outputs.has_tag }} |"
            echo "| Build triggered | yes |"
          } >> "$GITHUB_STEP_SUMMARY"