name: Build and push Docker image (amd64, arm64 to hub.docker.com and ghcr.io)

on:
  workflow_dispatch: # allow manual trigger
  # https://github.com/orgs/community/discussions/26276
  push:
    branches:
      - "main"
      - "v*"
    tags:
       - "v*"
    paths: # ignore changes to certain files
      - '**'
      - '!*.md'
      # - '!.github/**'
  pull_request: # runs when opened/reopned or when the head branch is updated, see https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request
    branches:
      - "main" # only PRs against main

jobs:
  docker:
    runs-on: ubuntu-latest
    steps:
      -
        name: Checkout
        uses: actions/checkout@v4
      -
        name: Set environment variables
        run: |
          BRANCH="${GITHUB_REF#refs/heads/}"
          echo "BRANCH=$BRANCH" >> "$GITHUB_ENV"
          echo "NOW=$(date -R)" >> "$GITHUB_ENV" # date -Iseconds; date +'%Y-%m-%dT%H:%M:%S'
          if [[ "$BRANCH" == "main" ]]; then
            echo "IMAGE_TAG=latest" >> "$GITHUB_ENV"
          else
            echo "IMAGE_TAG=$BRANCH" >> "$GITHUB_ENV"
          fi
      -
        name: Set up QEMU
        uses: docker/setup-qemu-action@v3
      -
        name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      -
        name: Login to Docker Hub
        uses: docker/login-action@v3
        if: github.event_name != 'pull_request' # TODO if DOCKERHUB_* are set?
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}
      -
        name: Login to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }} # actor is user that opened PR, was repository_owner before
          password: ${{ secrets.GITHUB_TOKEN }}
      -
        name: Build and push
        uses: docker/build-push-action@v6
        # if: github.event_name != 'pull_request' # still want to build image
        with:
          context: .
          push: ${{ github.event_name != 'pull_request' }} # TODO push for forks?
          build-args: |
            COMMIT=${{ github.sha }}
            BRANCH=${{ env.BRANCH }}
            NOW=${{ env.NOW }}
          platforms: linux/amd64,linux/arm64 # ,linux/arm/v7
          # TODO docker tag only if DOCKERHUB_* are set?
          tags: |
            ${{ secrets.DOCKERHUB_USERNAME }}/free-games-claimer:${{env.IMAGE_TAG}}
            ghcr.io/${{ github.actor }}/free-games-claimer:${{env.IMAGE_TAG}}
          cache-from: type=gha
          cache-to: type=gha,mode=max
