name: Docker Image CI

on:
  push:
    branches: ['main']
  pull_request:
    branches: ['main']

jobs:
  build:
    runs-on: ubuntu-latest

    permissions:
      contents: read
      packages: write

    steps:
      - name: Checkout
        uses: actions/checkout@v3

      - name: Setup Buildx
        uses: docker/setup-buildx-action@v2

      - name: Login to GitHub Container Registry
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v2
        with:
          registry: ghcr.io
          username: ${{github.actor}}
          password: ${{secrets.GITHUB_TOKEN}}

      - name: Extract metadata
        uses: docker/metadata-action@v4
        id: meta
        with:
          images: ghcr.io/jamsch0/groceries
          tags: type=raw,value=latest,enable={{is_default_branch}}

      - name: Build and push
        uses: docker/build-push-action@v4
        with:
          context: .
          cache-from: type=gha
          cache-to: type=gha,mode=max
          push: ${{github.event_name != 'pull_request'}}
          tags: ${{steps.meta.outputs.tags}}
          labels: ${{steps.meta.outputs.labels}}