name: Release Docker Image

on:
  release:
    types:
      - published

permissions:
  contents: read
  packages: write

jobs:
  docker:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Derive image name
        id: vars
        run: echo "image=ghcr.io/${GITHUB_REPOSITORY,,}" >> "$GITHUB_OUTPUT"

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Extract Docker metadata
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ steps.vars.outputs.image }}
          flavor: |
            latest=false
          tags: |
            type=raw,value=latest,enable=${{ github.event.release.prerelease == false }}
            type=semver,pattern={{version}},value=${{ github.event.release.tag_name }}
            type=semver,pattern={{major}}.{{minor}},value=${{ github.event.release.tag_name }}
            type=semver,pattern={{major}},value=${{ github.event.release.tag_name }}
          labels: |
            org.opencontainers.image.title=md-to-html
            org.opencontainers.image.description=Markdown to standalone HTML converter
            org.opencontainers.image.vendor=${{ github.repository_owner }}
            org.opencontainers.image.source=${{ github.server_url }}/${{ github.repository }}
            org.opencontainers.image.version=${{ github.event.release.tag_name }}

      - name: Build and push
        uses: docker/build-push-action@v6
        with:
          context: .
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}