name: Docker

# Publishes container images to GitHub Container Registry (ghcr.io).
#   master push  -> :edge, :sha  (amd64, fast)
#   tag v*       -> :X.Y.Z, :X.Y, :latest, :sha  (linux/amd64 + linux/arm64)
on:
  push:
    branches: [master]
    tags: ["v*"]
  workflow_dispatch:

permissions:
  contents: read
  packages: write

jobs:
  publish:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: docker/setup-qemu-action@v3
      - uses: docker/setup-buildx-action@v3
      - uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - id: meta
        uses: docker/metadata-action@v5
        with:
          images: ghcr.io/${{ github.repository }}
          tags: |
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}
            type=raw,value=latest,enable=${{ startsWith(github.ref, 'refs/tags/v') }}
            type=raw,value=edge,enable={{is_default_branch}}
            type=sha,format=short
      - uses: docker/build-push-action@v6
        with:
          context: .
          # multi-arch only for release tags (arm64 under emulation is slow)
          platforms: ${{ startsWith(github.ref, 'refs/tags/v') && 'linux/amd64,linux/arm64' || 'linux/amd64' }}
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          cache-from: type=gha
          cache-to: type=gha,mode=max