name: publish
on:
  push:
    branches:
      - main

jobs:
  publish:
    runs-on: ubuntu-latest
    permissions:
      packages: write
      contents: read

    steps:
      - uses: actions/checkout@main
      - name: Set up QEMU
        uses: docker/setup-qemu-action@master
        with:
          platforms: all
      - name: Set up Docker Buildx
        id: buildx
        uses: docker/setup-buildx-action@master

      - name: Log in to Github's container registry
        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u $ --password-stdin

      # Docker images have to have lowercase names, and Github Actions doesn't
      # have template functions
      - name: Collect image metadata
        id: meta
        uses: docker/metadata-action@master
        with:
          images: ghcr.io/${{ github.repository_owner }}/${{ github.event.repository.name }}

      - name: Build
        uses: docker/build-push-action@master
        with:
          context: .
          file: ./Dockerfile
          platforms: linux/amd64,linux/arm64
          push: true
          tags: ${{ steps.meta.outputs.tags }}