name: Docker

on:
  push:
    branches: ['main']

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}

permissions:
  contents: read
  packages: write

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        platform:
          - linux/arm64
          - linux/amd64

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

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v2
        if: ${{ matrix.platform != 'linux/amd64' }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2

      - name: Log in to the Container registry
        uses: docker/login-action@v2
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@v4
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=ref,event=branch
            type=raw,value=latest

      - name: Build and push by digest
        uses: docker/build-push-action@v4
        id: build
        with:
          context: .
          provenance: false
          labels: ${{ steps.meta.outputs.labels }}
          platforms: ${{ matrix.platform }}
          outputs: type=image,name=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }},push-by-digest=true,name-canonical=true,push=true

      - name: Export digests
        run: |
          mkdir -p /tmp/digests
          digest="${{ steps.build.outputs.digest }}"
          touch "/tmp/digests/${digest#sha256:}"

      - name: Upload digests
        uses: actions/upload-artifact@v3
        with:
          name: digests
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  push:
    runs-on: ubuntu-latest
    needs:
      - build

    steps:
      - name: Download digests
        uses: actions/download-artifact@v3
        with:
          name: digests
          path: /tmp/digests

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2

      - name: Log in to the Container registry
        uses: docker/login-action@v2
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@v4
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=ref,event=branch
            type=raw,value=latest

      - name: Create manifest list and push
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}@sha256:%s ' *)

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ steps.meta.outputs.version }}