name: Publish container image

on:
  release:
    types: [published]

permissions:
  contents: read

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}
  RELEASE_TAG: ${{ github.event.release.tag_name }}

jobs:
  test:
    name: Test release
    runs-on: ubuntu-latest
    services:
      postgres:
        image: postgres:17-alpine
        env:
          POSTGRES_DB: todo_test
          POSTGRES_USER: todo_test
          POSTGRES_PASSWORD: test-password
        ports:
          - 5432:5432
        options: >-
          --health-cmd "pg_isready -U todo_test -d todo_test"
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
    defaults:
      run:
        working-directory: app
    env:
      TEST_DATABASE_URL: postgres://todo_test:test-password@127.0.0.1:5432/todo_test?sslmode=disable
    steps:
      - name: Validate release tag
        working-directory: .
        run: |
          if [[ ! "$RELEASE_TAG" =~ ^v(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)(-((0|[1-9][0-9]*|[0-9]*[A-Za-z-][0-9A-Za-z-]*)(\.(0|[1-9][0-9]*|[0-9]*[A-Za-z-][0-9A-Za-z-]*))*))?(\+([0-9A-Za-z-]+(\.[0-9A-Za-z-]+)*))?$ ]]; then
            printf 'Release tag must use semantic versioning with a v prefix: %s\n' "$RELEASE_TAG" >&2
            exit 1
          fi

      - name: Check out release
        uses: actions/checkout@v6
        with:
          ref: ${{ env.RELEASE_TAG }}

      - name: Set up Go
        uses: actions/setup-go@v6
        with:
          go-version-file: app/go.mod
          cache-dependency-path: app/go.sum

      - name: Run tests
        run: go test ./...

      - name: Run vet
        run: go vet ./...

  publish:
    name: Publish image
    needs: test
    runs-on: ubuntu-latest
    concurrency:
      group: publish-image-${{ github.event.release.tag_name }}
      cancel-in-progress: false
    permissions:
      contents: read
      packages: write
      attestations: write
      id-token: write
    steps:
      - name: Check out release
        uses: actions/checkout@v6
        with:
          ref: ${{ env.RELEASE_TAG }}

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v3

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

      - name: Log in to GHCR
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Generate image metadata
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=semver,pattern={{raw}},value=${{ env.RELEASE_TAG }}
            type=semver,pattern={{version}},value=${{ env.RELEASE_TAG }}
            type=semver,pattern={{major}}.{{minor}},value=${{ env.RELEASE_TAG }}
            type=semver,pattern={{major}},value=${{ env.RELEASE_TAG }},enable=${{ !startsWith(env.RELEASE_TAG, 'v0.') }}
            type=raw,value=latest,enable=${{ !github.event.release.prerelease }}
          labels: |
            org.opencontainers.image.description=Server-rendered Go todo application deployed to Hetzner Cloud
          annotations: |
            org.opencontainers.image.description=Server-rendered Go todo application deployed to Hetzner Cloud
        env:
          DOCKER_METADATA_ANNOTATIONS_LEVELS: manifest,index

      - name: Build and push image
        id: push
        uses: docker/build-push-action@v6
        with:
          context: app
          file: app/Dockerfile
          platforms: linux/amd64,linux/arm64
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          annotations: ${{ steps.meta.outputs.annotations }}

      - name: Attest image provenance
        uses: actions/attest@v4
        with:
          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          subject-digest: ${{ steps.push.outputs.digest }}
          push-to-registry: true