release.yml

name: Release on PR merge

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

permissions:
  contents: write
  pull-requests: read

jobs:
  release:
    name: Create GitHub Release
    runs-on: ubuntu-latest
    if: github.event.pull_request.merged == true
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: 20

      - name: Get version from package.json
        id: package_version
        run: |
          VERSION=$(node -p "require('./package.json').version")
          echo "version=$VERSION" >> $GITHUB_OUTPUT
          echo "tag=v$VERSION" >> $GITHUB_OUTPUT
          echo "Package version: $VERSION"

      - name: Check if tag already exists
        id: check_tag
        run: |
          TAG="v${{ steps.package_version.outputs.version }}"
          if git rev-parse --verify "refs/tags/$TAG" >/dev/null 2>&1; then
            echo "tag_exists=true" >> $GITHUB_OUTPUT
            echo "Tag $TAG already exists, skipping release"
          else
            echo "tag_exists=false" >> $GITHUB_OUTPUT
            echo "Tag $TAG does not exist, proceeding with release"
          fi

      - name: Extract release notes from CHANGELOG
        if: steps.check_tag.outputs.tag_exists == 'false'
        id: release_notes
        run: |
          VERSION="${{ steps.package_version.outputs.version }}"
          echo "Extracting release notes for version $VERSION from CHANGELOG.md"

          if [ ! -f CHANGELOG.md ]; then
            echo "CHANGELOG.md not found, using PR information"
            echo "## Changes" > release_notes.md
            echo "Merged PR #${{ github.event.pull_request.number }}: ${{ github.event.pull_request.title }}" >> release_notes.md
            echo "" >> release_notes.md
            echo "${{ github.event.pull_request.body }}" >> release_notes.md
          else
            # Extract the section for this version from CHANGELOG.md
            awk -v version="$VERSION" '
              BEGIN { 
                found=0
                in_section=0
                content_found=0
              }
              # Match version headers like ## [1.18.0], ## [v1.18.0], ## [1.18.0] - 2025-10-14, or ## [Unreleased]
              /^## \[/ {
                if (in_section && content_found) {
                  # We hit the next section, stop here
                  exit
                }
                if ($0 ~ "\\[v?"version"\\]" || ($0 ~ "\\[Unreleased\\]" && !found)) {
                  found=1
                  in_section=1
                  next
                } else {
                  in_section=0
                }
              }
              # Skip empty lines at the start of a section
              in_section && /^$/ && !content_found { 
                next 
              }
              # Capture content within the section
              in_section && !/^## \[/ { 
                print
                if ($0 !~ /^$/) content_found=1
              }
            ' CHANGELOG.md > release_notes.md
            
            # If no content found in CHANGELOG, try Unreleased section
            if [ ! -s release_notes.md ]; then
              echo "No specific version found, trying Unreleased section"
              awk '
                BEGIN { in_unreleased=0; content_found=0 }
                /^## \[Unreleased\]/ { in_unreleased=1; next }
                /^## \[/ && in_unreleased { exit }
                in_unreleased && /^$/ && !content_found { next }
                in_unreleased { 
                  print
                  if ($0 !~ /^$/) content_found=1
                }
              ' CHANGELOG.md > release_notes.md
            fi
            
            # Final fallback to PR information
            if [ ! -s release_notes.md ]; then
              echo "No CHANGELOG content found, using PR information"
              echo "## Changes" > release_notes.md
              echo "Merged PR #${{ github.event.pull_request.number }}: ${{ github.event.pull_request.title }}" >> release_notes.md
              if [ -n "${{ github.event.pull_request.body }}" ]; then
                echo "" >> release_notes.md
                echo "${{ github.event.pull_request.body }}" >> release_notes.md
              fi
            fi
          fi

          echo "Generated release notes:"
          echo "========================"
          cat release_notes.md
          echo "========================"

          # Set output for GitHub Actions
          echo "notes<<EOF" >> $GITHUB_OUTPUT
          cat release_notes.md >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT

      - name: Get current date
        if: steps.check_tag.outputs.tag_exists == 'false'
        id: date
        run: echo "date=$(date +'%Y-%m-%d')" >> $GITHUB_OUTPUT

      - name: Create Git tag
        if: steps.check_tag.outputs.tag_exists == 'false'
        run: |
          TAG="${{ steps.package_version.outputs.tag }}"
          git config --local user.email "action@github.com"
          git config --local user.name "GitHub Action"
          git tag -a "$TAG" -m "Release $TAG"
          git push origin "$TAG"
          echo "Created and pushed tag: $TAG"

      - name: Create GitHub Release
        if: steps.check_tag.outputs.tag_exists == 'false'
        uses: actions/create-release@v1
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        with:
          tag_name: ${{ steps.package_version.outputs.tag }}
          release_name: ${{ steps.package_version.outputs.tag }} - ${{ steps.date.outputs.date }}
          body: ${{ steps.release_notes.outputs.notes }}
          draft: false
          prerelease: false

      - name: Skip release (tag exists)
        if: steps.check_tag.outputs.tag_exists == 'true'
        run: |
          echo "Tag ${{ steps.package_version.outputs.tag }} already exists, skipping release creation"
          echo "If you need to create a new release, update the version in package.json"