name: test-container-build

on:
  push:
    branches: [ 'prep-*' ]

permissions:
  contents: read
  packages: write

jobs:
  container-build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

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

      - name: Build & push
        uses: docker/build-push-action@v5
        with:
          context: .
          file: Dockerfile
          push: true
          # Tag with prep suffix to avoid conflicts with production
          tags: |
            ghcr.io/${{ github.repository }}:${{ github.ref_name }}